JP3783269B2 - Rolling bearing with sealing plate - Google Patents

Description

[0001]
[Industrial application fields]
The rolling bearing with a sealing plate according to the present invention is used for constituting a rotation support portion of various mechanical devices.
[0002]
[Prior art]
A rolling bearing 1 with a sealing plate as shown in FIGS. 3 to 4 is used to constitute a rotation support portion of various mechanical devices. The rolling bearing 1 with a sealing plate includes an inner ring 2 and an outer ring 3, a plurality of rolling elements 4, and a pair of sealing plates 5, 5 arranged concentrically with each other. Of these, the inner ring 2 has an inner ring raceway 6 formed at the center of the outer peripheral surface and seal grooves 7 and 7 formed at both ends of the outer peripheral surface. Further, the outer ring 3 has an outer ring raceway 8 formed in the center portion of the inner peripheral surface and locking grooves 9 and 9 formed at both ends of the inner peripheral surface. The plurality of rolling elements 4 are rotatably provided between the inner ring raceway 6 and the outer ring raceway 8 in a state in which the rolling elements 4 are rotatably held by the cage 10. Further, the sealing plates 5 and 5 are formed in an annular shape as a whole by reinforcing elastic materials 12 and 12 such as rubber and elastomer with annular metal cores 11 and 11, respectively. Such sealing plates 5 and 5 engage the outer peripheral edges of the elastic members 12 and 12 with the engaging grooves 9 and 9 and the inner peripheral edges of the elastic members 12 and 12 with the seals. The inner surfaces 13 and 13 of the grooves 7 and 7 are in sliding contact.
[0003]
The rolling bearing 1 with a sealing plate configured as described above performs relative rotation between a member with the inner ring 2 fitted and fixed and a member with the outer ring 3 fitted and fixed based on the rolling of the plurality of rolling elements 4. Allow. Further, the pair of sealing plates 5 and 5 prevent the grease filled in the portion where the rolling element 4 is installed from leaking to the outside, and foreign matters such as dust floating in the surrounding space are prevented from flowing into the rolling element 4. Prevents intrusion into the installed part.
[0004]
[Problems to be solved by the invention]
In the case of a conventional rolling bearing with a sealing plate constructed and operated as described above, the elastic members 12 constituting the respective sealing plates 5 and 5 under severe use conditions such that the operation speed of the rolling bearing increases rapidly. Adhesion between the inner peripheral edge 12 and the inner side surfaces 13 of the seal grooves 7 and 7 may not be ensured. That is, the inner peripheral edge of each of the elastic members 12 and 12 is based on the elasticity generated by elastically locking the outer peripheral edge of each of the elastic members 12 and 12 to the locking grooves 9 and 9. 13 and 13 are pressed.
[0005]
Under normal use conditions, a sufficient contact pressure between the inner peripheral edge of each elastic member 12, 12 and each inner side surface 13, 13 can be secured. It has been empirically known that the contact pressure is lowered and the sealing performance is deteriorated under a use condition such that it is operated for a long time. Such a decrease in sealing performance is not preferable because grease filled in the rolling bearing leaks or foreign matter floating in the external space enters the rolling bearing.
[0006]
If the force pressing the inner peripheral edge of each elastic member 12, 12 against each inner side face 13, 13 can be increased, the sealing performance can be ensured even during high speed operation, but the sliding between the inner peripheral edge and the inner side faces 13, 13 can be ensured. This is not preferable because the frictional force acting on the contact portion increases and the torque required to rotate the rolling bearing 1 with the sealing plate increases.
The rolling bearing with a sealing plate of the present invention was invented to eliminate all of these disadvantages.
[0007]
[Means for Solving the Problems]
The rolling bearing with a sealing plate according to the present invention includes an inner ring formed with an inner ring raceway at a central portion of the outer peripheral surface and a seal groove at an end portion of the outer peripheral surface, and a central portion of the inner peripheral surface, similar to the conventional rolling bearing with a sealing plate. An outer ring raceway, an outer ring formed with a locking groove at the end of the inner peripheral surface, a plurality of rolling elements provided between the inner ring raceway and the outer ring raceway so as to be freely rollable, and the entire ring shape. And a sealing plate that is formed and locks the outer peripheral edge of the locking groove. And the edge of the elastic material which comprises the inner peripheral edge part of this sealing board is made to slide-contact with the inner surface of the said seal groove.
In particular, in the rolling bearing with a sealing plate according to the present invention, the seal groove includes a cylindrical bottom surface, a pair of side surfaces inclined in a direction in which the interval increases toward the opening, and ends of both side surfaces. And a curved surface portion that continues the end portion of the bottom surface. And the edge of the said elastic material is in sliding contact with the curved-surface part of these.
[0008]
[Action]
In the case of the rolling bearing with a sealing plate of the present invention configured as described above, the contact pressure between the edge of the elastic material and the curved surface portion is secured even under severe conditions such as during high speed operation, Ensuring sealing performance with a plate.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an example of an embodiment of the present invention. The feature of the present invention is that the sliding contact portion on the inner peripheral edge of the elastic member 12 constituting the sealing plate 5 is devised in order to improve the sealing performance by the sealing plate 5. Since the basic structure itself of the rolling bearing with a sealing plate is the same as that of the conventional structure shown in FIG. 3, the illustration and description regarding the equivalent parts are omitted or simplified, and the following description will focus on the characteristic parts of the present invention.
[0010]
In the rolling bearing with a sealing plate of the present invention, the cross-sectional shape of the seal groove 7 formed on the outer peripheral surface of both end portions of the inner ring 2 is a trapezoid with rounded corners in order to allow the inner peripheral edge of the elastic material 12 to enter. is there. That is, the seal groove 7 includes a cylindrical bottom surface 14, a pair of side surfaces 15 and 16 which are inclined in a direction in which the distance increases toward the opening, the end portions of the both side surfaces 15 and 16, and the bottom surface. 14 are provided with curved surface portions 17 and 18 that are continuous with the 14 end portions. More specifically, the cross-sectional shape of the bottom surface 14 is a straight line parallel to the central axis of the inner ring 2 as shown by a chain line a in FIG. The cross-sectional shapes of the side surfaces 15 and 16 are straight lines as shown by chain lines b and c in FIG. And the space | interval of the straight lines b and c showing the intermediate part shape of each of these side surfaces 15 and 16 spreads, so that it goes to a diameter direction outer side (upper side of FIG. 2). That is, the width dimension of the seal groove 7 (the dimension in the left-right direction in FIG. 2) becomes wider toward the opening. Furthermore, the continuous part of the both ends of the said bottom face 14 and said each side surface 15 and 16 is smoothly continued by the curved-surface parts 17 and 18 whose cross-sectional shape is circular arc shape. That is, the bottom surface 14 and the side surfaces 15 and 16 are continuous from both end portions of the curved surface portions 17 and 18 in the tangential direction of the curved surface portions 17 and 18.
[0011]
The inner peripheral edge of the elastic member 12 is in sliding contact with the curved surface portion 17 that is located near the center of the inner ring 2 in the axial direction (left-right direction in FIG. 1). In addition, it is preferable that the position where the inner peripheral edge is in sliding contact is as central as possible in the curved surface portion 17. Then, the dimensional error, assembly error, and the like of the constituent members are regulated so that the inner peripheral edge is not detached from the curved surface portion 17 regardless of unavoidable dimensional errors.
[0012]
In the case of the rolling bearing with a sealing plate of the present invention configured as described above, the contact pressure between the inner peripheral edge of the elastic member 12 and the curved surface portion 17 is ensured even under severe conditions such as during high speed operation. Thus, the sealing performance by the sealing plate 5 can be ensured. That is, as a result of repeated experiments conducted by the inventor with various contact positions of the inner peripheral edge of the elastic material 12 being different, if the inner peripheral edge is brought into sliding contact with the curved surface portion 17, high speed It has been found that sufficient sealing performance can be obtained even during rotation.
[0013]
【Example】
In order to confirm the effect of the present invention, an experiment conducted by the present inventor will be described. The experimental conditions are as follows.
Conditions common to the comparison product and the present invention Bearing outer ring outer diameter: 35 mm
Inner ring inner diameter: 17mm
Outer ring width: 10mm
Rolling element: 10 balls with outer diameter of 3/16 inch Sealing plate core metal thickness: 0.3mm
Same outer diameter: 32mm
Same inner diameter: 21mm
Elastic material: NBR
Operation condition Rotation condition: Inner ring rotation speed: 4500 rpm
Radial load: 10kgf
Evaluation conditions 400 g of test dust specified as JIS Z 8901 as three types is put into a 500 mm x 500 mm x 500 mm cube container, and a rolling bearing with a sealing plate whose sealability is to be evaluated is placed in a state of stirring by a blower. After continuing the operation at room temperature for 24 hours, the sealing plate was removed, and the presence or absence of dust entering the inside of the rolling bearing was determined.
[0014]
As a result of the above-described experiment, as shown in FIG. 4, in the case of a structure in which the inner peripheral edge of the elastic member 12 is in sliding contact with the inner surface 13 of the seal groove 7, the grease sealed in the rolling bearing is used. There was dust inside. On the other hand, as shown in FIG. 1, in the case of the structure in which the inner peripheral edge of the elastic member 12 is in sliding contact with the curved surface portion 17, no dust was confirmed inside the grease sealed in the rolling bearing. .
[0015]
【The invention's effect】
The rolling bearing with a sealing plate according to the present invention is configured and operated as described above, and even if the usage conditions are severe, the leakage of grease and the entry of foreign matter can be reliably prevented. And the durability of the rotation support portion can be improved.
[Brief description of the drawings]
FIG. 1 shows an example of an embodiment of the present invention and corresponds to part A of FIG.
FIG. 2 is a diagram showing a cross-sectional shape of a seal groove.
FIG. 3 is a partial sectional view showing an example of a conventional rolling bearing with a sealing plate.
4 is an enlarged view of a part A in FIG. 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rolling bearing with a sealing plate 2 Inner ring 3 Outer ring 4 Rolling body 5 Sealing plate 6 Inner ring raceway 7 Sealing groove 8 Outer ring raceway 9 Locking groove 10 Cage 11 Core metal 12 Elastic material 13 Inner side surface 14 Bottom surface 15, 16 Side surface 17, 18 Curved surface Part

Claims (1)

An inner ring raceway at the center of the outer peripheral surface, an inner ring formed with a seal groove at the end of the outer peripheral surface, an outer ring raceway at the center of the inner peripheral surface, and an outer ring formed with a locking groove at the end of the inner peripheral surface; A plurality of rolling elements provided between the inner ring raceway and the outer ring raceway so as to be freely rollable, and a sealing plate that is formed in an annular shape and has its outer peripheral edge locked in the locking groove, In the rolling bearing with a sealing plate in which the edge of the elastic material constituting the inner peripheral edge of the sealing plate is slidably contacted with the inner surface of the sealing groove, the sealing groove is formed on the cylindrical bottom surface and the opening. It has a pair of side surfaces that are inclined in the direction in which the interval becomes wider as it goes, and a curved surface portion that connects the end portions of both side surfaces and the end portions of the bottom surface, and the edge of the elastic material is the edge of the elastic material. A rolling bearing with a sealing plate, characterized in that it is in sliding contact with the curved surface.

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