CN106870567B

CN106870567B - Bearing seal and drawing jig

Info

Publication number: CN106870567B
Application number: CN201610846653.0A
Authority: CN
Inventors: 木村大碁
Original assignee: NTN Corp
Current assignee: NTN Corp
Priority date: 2015-09-25
Filing date: 2016-09-23
Publication date: 2020-01-24
Anticipated expiration: 2036-09-23
Also published as: JP2017062001A; DE112016004295T5; CN206617446U; JP6537420B2; CN106870567A; WO2017051869A1

Abstract

The invention provides a seal for a bearing, wherein a hole (12) penetrating along the axial direction is formed in an annular plate part (10) of a core (4) to which rubber materials of seal lips (1, 2) of the seal for a bearing are attached, and a cover which is attached to the whole circumferential range of a plate thickness surface (14) forming the hole (12) and completely seals the hole (12) is formed by the rubber materials. An outer side slit (15) is formed to divide the outer surface of the cap (13) and the portion of the rubber material other than the cap (13) along the entire circumference of the plate thickness surface (14), and an inner side slit (17) is formed to divide the inner surface of the cap (13) and the portion of the rubber material other than the cap (13) along the range of not less than half the circumference of the plate thickness surface (14).

Description

Bearing seal and drawing jig

Technical Field

The present invention relates to a bearing seal used for sealing a rolling bearing, and a drawing jig used for removing the bearing seal from a bearing ring.

Background

A general bearing seal has a seal lip formed of a rubber material and an annular core to which the rubber material is attached, and can be attached by press-fitting into a bearing ring.

Conventionally, in order to facilitate removal of a bearing seal, a bearing seal has been proposed in which holes penetrating an annular plate portion of a core in an axial direction are formed so as to be arranged in a circumferentially dispersed manner, and a cap for closing the holes is formed of the above-described rubber material. Such a bearing seal is formed with a hole from the outside of the bearing, and the hook portion of the drawing jig is inserted through the hole, and the bearing seal can be drawn from the bearing ring by hooking the hook portion to the bearing seal from the inside of the bearing and pulling the hook portion in the axial direction. As such a drawing jig, a detacher used for drawing gears, pulleys, bearings, and the like is used (

patent documents

1 and 2 listed below).

Patent document 1: japanese patent laid-open publication No. 9-317897 (particularly FIG. 6, paragraph 0039)

Patent document 2: japanese patent laid-open No. 2008-281025 (especially FIGS. 2 and 3, paragraph 0030)

When the hole of the annular plate portion is completely closed with the cover as in the bearing seal of patent document 1, there is no fear that foreign matter enters the inside of the bearing through the hole, and the sealing performance is excellent. However, a sharp tool is required to pierce the cap or a blade tool is required to cut the hole, and in this case, there is a concern that the bearing components such as the retainer and the rolling elements inside the bearing may be damaged.

On the other hand, in the case where a gap is formed in advance in the cover as in the bearing seal of patent document 2, although the hole forming operation is not required, there is a concern that a gap may be enlarged and foreign matter may be sucked into the bearing due to a pressure change in the bearing during operation of the bearing.

Disclosure of Invention

In view of the above background, the present invention has been made to solve the problem of preventing damage to a bearing during a hole-forming operation for drawing the bearing without sacrificing the sealing performance of the bearing seal.

In order to achieve the above object, the present invention employs a structure in which a seal for a bearing includes a seal lip formed of a rubber material and an annular core to which the rubber material is attached, holes penetrating an annular plate portion of the core in an axial direction are formed so as to be arranged in a dispersed manner in a circumferential direction, a cap that closes the holes is formed of the rubber material, the cap is attached to an entire circumferential range of a plate thickness surface on which the holes are formed and completely closes the holes, an outer-side slit that divides an outer surface of the cap and a portion of the rubber material other than the cap along the entire circumference of the plate thickness surface is formed, and an inner-side slit that divides an inner surface of the cap and the portion of the rubber material other than the cap along a range of half circumference or more of the plate thickness surface is formed.

According to the above configuration, since the cap is attached to the entire circumference of the plate thickness surface on which the hole is formed and the hole is completely closed, the sealing performance of the bearing seal is not sacrificed, and it is not necessary to continue the other portion of the rubber material with the cap. The outer surface of the cap is divided by the outer side slit along the entire circumference of the plate thickness surface from the portion of the rubber material other than the cap, and the inner surface of the cap is divided by the inner side slit along the range of the half circumference or more of the plate thickness surface. Therefore, it is not necessary to use a sharp tool or a sharp blade tool for the drilling operation.

Thus, according to the present invention, even if the hole formed in the annular plate portion of the core is completely closed by the cover, the hole forming operation using a sharp tool or a blade tool is not required, and therefore, the bearing can be prevented from being damaged during the hole forming operation without sacrificing the sealing performance of the bearing seal.

Drawings

Fig. 1A is a sectional view showing a bearing seal according to an embodiment of the present invention.

Fig. 1B is a partial sectional view showing a state in which the hole 12 is opened from the state of fig. 1A.

Fig. 2A is an enlarged side view showing a part of the bearing seal shown in fig. 1A in the circumferential direction from the outside.

Fig. 2B is an enlarged side view showing the vicinity of a cap of the bearing seal shown in fig. 1A from the inside of the bearing.

Fig. 3 is a sectional view showing a drawing jig according to an embodiment of the present invention.

Fig. 4 is a front view showing a hook portion of the drawing jig according to the embodiment of the present invention.

Fig. 5 is a plan view of the drawing jig shown in fig. 3.

Fig. 6 is a cross-sectional view showing a state where the bearing seal is pulled out by the drawing jig shown in fig. 3.

Detailed Description

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

As shown in fig. 1A, the bearing seal according to the embodiment includes

seal lips

1 and 2 and a waist portion 3 formed of a rubber material, and a core 4 to which the rubber material is attached. The bearing seal is a spacer for separating the inside (inside of the bearing) of the rolling bearing 5 from the outside by being attached to the inner peripheral end portion of the outer race 7 of the inner and

outer races

6 and 7 of the rolling bearing 5. The

seal lips

1 and 2 function as oil seals by engaging with a seal surface 8 on the ferrule 6 side present on the inner side.

The center axis of the bearing seal coincides in design with the bearing center axis of the rolling bearing 5. Hereinafter, the direction along the central axis thereof is simply referred to as "axial direction", the direction perpendicular to the central axis is simply referred to as "radial direction", and the circumferential direction around the central axis is simply referred to as "circumferential direction". The rolling bearing 5 is a tapered roller bearing as an example, but the type of bearing to which the bearing seal is applied is not particularly limited, and the bearing can be applied to a cylindrical roller bearing, a ball bearing, or the like.

The core 4 includes an annular plate 10 formed over the entire circumferential range, and a flange 11 bent in the axial direction from the outer periphery of the annular plate 10. The entirety of the core bar 4 is generally formed integrally by press working.

The

seal lips

1 and 2 extend in a tongue-like shape from the waist portion 3 attached so as to straddle the annular plate portion 10 toward the seal surface 8. In the drawings, a structure having two radial lips is exemplified, but the number of the seal lips, the radial lips or the axial lips, and whether or not the seal surface is in contact with the seal surface are not concerned.

The flange portion 11 of the core 4 is press-fitted to the inner peripheral end portion of the ferrule 7. By this press-fitting, the bearing seal is attached to the ferrule 7.

As shown in fig. 1B, the holes 12 penetrating the annular plate portion 10 of the core 4 in the axial direction are formed so as to be circumferentially distributed. As shown in fig. 1A and 2A, the cover 13 for blocking the hole 12 is formed of the same rubber material as the

seal lips

1 and 2 and the waist portion 3. In the drawings, the holes 12 are illustrated as long holes whose long axes are defined along a direction of one tangent line of the outer periphery of the annular plate portion 10, and the holes 12 are arranged at two positions at equal intervals in the circumferential direction.

The thickness of the core 4 and the shape and arrangement of the hole 12 may be appropriately determined so as not to excessively deform the vicinity of the hole 12 when the core 4 is removed, taking into consideration the mechanical strength required for the core 4, the form of a drawing jig used for removing the bearing seal, the magnitude of external force applied to the bearing seal when the bearing seal is removed, and the difficulty of molding the cap 13 or the hole 12. For example, the holes 12 may be circular holes, square holes, elliptical holes, or the like, or may be arranged at three or more positions in the circumferential direction.

The lid 13 is attached to the entire circumference of the plate thickness surface 14 forming one circumference of the hole 12, and completely closes the hole 12.

An outer side slit 15 is formed along the entire periphery of the plate thickness surface 14 to divide the outer surface of the cover 13 and a portion (for example, the waist portion 3) of the rubber material other than the cover 13. Here, the outer surface of the cap 13 is a cap surface exposed to the bearing outer side in the axial projection region of the hole 12. The outer side slit 15 is formed in a slit shape recessed axially above the outer side plate surface 16 of the annular plate portion 10.

On the other hand, as shown in fig. 1A and 2B, inner slits 17 are formed to divide the inner surface of the lid 13 and the portion of the rubber material other than the lid 13 along the range of not less than half the circumference of the plate thickness surface 14. Here, the inner surface of the cap 13 is a cap surface exposed to the inside of the bearing in the axial projection region of the hole 12. The inner slits 17 are formed in a slit shape recessed in the axial direction to be equal to or more than the inner side plate surface 18 of the annular plate portion 10.

As shown in fig. 1A, the thickness of the attachment portion between the lid 13 and the plate thickness surface 14 in the axial direction is smaller than the plate thickness of the plate thickness surface 14. The thickness of the adhering portion and the axial depths of the outer gap 15 and the inner gap 17 are set to a dimension that can maintain the adhesion between the cap 13 and the plate thickness surface 14 while withstanding the pressure change inside the shaft allowed by the rolling bearing 5.

Further, the connecting portion 19 attached to the inner side plate surface 18 of the annular plate portion 10 and continuous with the inner surface of the lid 13 is formed of the aforementioned rubber material. The inner slit 17 is formed to be shorter than the entire periphery of the plate thickness surface 14, and a connecting portion 19 is formed to be continuous with the inner surface of the lid 13 at the interrupted portion of the inner slit 17. The connecting portion 19 is along one of the linear portions of the two parallel sides of the plate thickness surface 14. Therefore, when the cap 13 is pressed in the axial direction from the outside and the adhesion between the cap 13 and the plate thickness surface 14 is broken, the cap 13 falls toward the inside of the bearing with the connection portion 19 as a center, and is held in a state of being connected to the core 4 through the connection portion 19, as shown in fig. 1B.

The rubber material forming the

seal lips

1, 2, the waist portion 3, the covers 13, and the connecting portion 19 can be molded and attached to the core 4 at the same time by vulcanization-bonding the core 4 in a mold housing the core 4. The rubber material may be suitably rubber for oil seal such as nitrile rubber, silicone rubber, fluororubber, or the like.

Fig. 3 shows a drawing jig used to remove the bearing seal from the ferrule 7. The drawing jig includes: a pulling shaft 100 serving as a transmission path for applying a pulling force to the bearing seal; a support body 101 that determines the position of the pulling shaft 100 with respect to the ferrule 7 in the radial direction and the axial direction; and a nut 102 used to axially move the pulling shaft 100 with respect to the support body 101 and the ferrule 7.

The pulling shaft 100 includes: a hook 103; a connecting shaft 104; a bolt 105 for fastening the hook 103 and the shaft 104; and an external thread portion 106 that can be screwed to the coupling shaft portion 104 and the nut 102, respectively.

On the other hand, the support 101 includes: a support plate portion 108 having an opening 107 formed in a position corresponding to the hole 12 so that the male screw portion 106 can pass through in the axial direction; a bracket portion 109 for supporting the support plate portion 108 with respect to the ferrule 7; and a bolt 110 fastening the bracket portion 109 and the support plate portion 108.

As shown in fig. 3 and 4, the hook 103 has a distal end surface that is bent in the radial direction from a flat plate portion extending in the axial direction. As shown in fig. 3, the flat plate portion of the hook 103 is fastened to one end side of the coupling shaft 104 on the lower side in the figure by a bolt 105. As shown in fig. 1B and 3, the distal end surface of the hook 103 is formed into a circular arc surface shape that can be inserted into the hole 12 in the axial direction. The reason why the distal end surface of the hook 103 is a curved surface in the form of a circular arc is to prevent the distal end surface of the hook 103 from damaging a retainer or the like inside the bearing when the bearing is inserted deeply by mistake.

As shown in fig. 3, the coupling shaft portion 104 has a female screw that can be screwed from one end of a male screw portion 106 formed of a stud on one end side of the upper side in the drawing. The male screw portion 106 and the coupling shaft portion 104 are integrated by this screwing.

The male screw portion 106 axially penetrating the opening 107 of the support plate portion 108 protrudes upward from the upper plate surface of the support plate portion 108 in the figure. The nut 102 is screwed into the male screw portion 106 from an upper end of the male screw portion 106 in the drawing.

As shown in fig. 3 and 5, the bracket portion 109 is composed of a pair of legs that support the support plate portion 108 to the ferrule 7 in the axial direction and the radial direction by contact with the ferrule 7. Each leg of the holder portion 109 has an end portion (lower end portion in fig. 3) having a width in the circumferential direction and being capable of abutting against the fitting surface and the side surface with a diametrical line of the fitting surface of the ferrule 7 as a center, and is capable of being positioned in the radial direction and the axial direction with respect to the ferrule 7 by the pair of end portions.

The opening 107 through which the male screw portion 106 passes is a long hole that is long in the radial direction. Further, the opening 111 through which the bolt 110 for fastening the support plate portion 108 and the bracket portion 109 passes is also an elongated hole elongated in the radial direction along the opening 107. Here, the openings 107 and 111 are long holes in order to enable the support positions of the pair of leg portions constituting the holder portion 109 and the pulling shaft 100 to be adjusted in the radial direction with respect to the support plate portion 108, and the pulling jig can be used for rolling bearings and bearing seals having different main dimensions.

When the bearing seal is removed by using the drawing jig, for example, as shown in fig. 3, the rolling bearing 5 is horizontally placed. And the hook 103 is used alone, the cap 13 shown in fig. 1A is pressed from the bearing outside by the distal end face of the hook 103. Thereby, the adhering portion between the cover 13 and the plate thickness surface 14 is broken, and as shown in fig. 1B, the cover 13 is opened with the connection portion 19 as the center and the hole 12 is opened, and the hook 103 is inserted into the opened hole 12. The support body 101 is provided from above the ferrule 7. The hook 103 connecting the shaft 104 and the insertion hole 12 is fastened by the bolt 105, and the pull shaft 100 is hooked by the support plate 108 by the nut 102. The pulling shaft 100 is moved along the opening 107 as necessary to adjust the hooking of the bearing seal to the hook 103. The same operation is performed for all the caps 13 and the like. And then each nut 102 is rotated. The pulling shaft 100 as a whole moves in the axial direction (upward in the drawing) with respect to the support body 101 and the ferrule 7 as shown in fig. 6 due to the axial force of the male screw portion 106 generated along with the rotation of the nut 102, and the bearing seal is pulled in the axial direction by the hook portion 103. Therefore, by sequentially slightly rotating each nut 102, the bearing seal is pulled out from the ring 7.

The bearing seal is a member as described above, and as shown in fig. 1A, the cover 13 is attached to the entire circumference of the plate thickness surface 14 in which the hole 12 is formed, and completely closes the hole 12, so that the sealing performance of the bearing seal is not sacrificed.

In the seal for a bearing, since the outer surface of the cap 13 and the portion of the rubber material other than the cap 13 are divided by the outer side slit 15 along the entire circumference of the plate thickness surface 14 and the inner surface of the cap 13 is divided by the inner side slit 17 along the range of the half circumference or more of the plate thickness surface 14, the position of the cap 13 can be recognized from the outside of the bearing by observing the outer side slit 15, and the thin adhered portion between the plate thickness surface 14 and the cap 13 can be broken only by lightly pressing the cap 13 from the outer side in the axial direction. Therefore, the bearing seal does not require a drilling operation for drawing with a sharp tool or a blade tool, and can prevent damage to the bearing during the drilling operation.

Further, since the bearing seal is adhered to the inner side plate surface 18 of the annular plate portion 10 and the connection portion 19 continuous to the inner surface of the cap 13 is formed of a rubber material, the cap 13 can be prevented from being separated from the core 4 and falling into the bearing during the boring operation (see fig. 1B).

As shown in fig. 3 and 4, the drawing jig includes: a pull shaft 100 having a hook 103 that can be inserted into the hole 12 of the bearing seal, and an external thread 106 that can move in the axial direction integrally with the hook 103; a support body 101 having a support plate portion 108 in which an opening 107 through which the male screw portion 106 can pass in the axial direction is formed in an arrangement corresponding to the hole 12, and a bracket portion 109 that supports the support plate portion 108 with respect to the ferrule 7 in the radial direction and the axial direction by contact with the ferrule 7 to which the bearing seal is attached; and the nut 102 that can be screwed to the male screw portion 106 from the opposite side of the ferrule 7 with respect to the support plate portion 108, so that the bearing seal can be extracted from the ferrule 7 without receiving a shaft body of a drawing jig inside the ferrule 7, unlike the detacher of the conventional example.

In particular, in this drawing jig, the holder portion 109 of the support body 101 is supported by the fitting surface of the outer race 7, and there is an advantage that it is easy to cope with a small-diameter rolling bearing, as compared with the case of supporting by the fitting surface of the inner race 6.

It is intended that all points of the embodiments disclosed herein are to be considered illustrative rather than restrictive. Therefore, the scope of the present invention is defined by the scope of the claims rather than the description above, and all modifications equivalent to the meaning and scope of the claims are included.

Description of the reference numerals

1. 2 … sealing lip; 3 … waist; 4 … mandril; 5 … rolling bearings; 6. 7 … a ferrule; 10 … annular plate portion; 12 … holes; 13 … a cover; 14 … board thickness side; 15 … outer side slits; 16 … outer side panel faces; 17 … internal side gap; 18 … internal side panel faces; 19 … connection part; 100 … pulling the shaft; 101 … support body; 102 … nut; 106 … external threaded portion; 107 … opening; 108 … support plate portions; 109 … bracket portion.

Claims

1. A seal for a bearing, which has a seal lip formed of a rubber material and an annular core member to which the rubber material is adhered, and in which holes penetrating an annular plate portion of the core member in an axial direction are formed so as to be circumferentially distributed, and a cap for closing the holes is formed of the rubber material,

it is characterized in that the preparation method is characterized in that,

the cover is attached to the whole circumference of the plate thickness surface forming the hole and completely seals the hole,

an outer side slit is formed along the entire periphery of the plate thickness surface to separate the outer surface of the cover from the portion of the rubber material other than the cover,

an inner side slit is formed to divide an inner surface of the cap and a portion of the rubber material other than the cap along a range of a half or more of a thickness of the plate.

2. The seal for bearings according to claim 1,

the connection portion, which is attached to the inner side plate surface of the annular plate portion and is continuous with the inner surface of the lid, is formed of the rubber material.

3. A drawing jig is characterized by comprising:

a pull shaft having a hook portion that can be inserted into the hole of the bearing seal according to claim 1 or 2, and an external thread portion that can move in the axial direction integrally with the hook portion;

a support body having a support plate portion in which an opening through which the male screw portion can pass in an axial direction is formed in a position corresponding to the hole, and a bracket portion that supports the support plate portion in a radial direction and an axial direction by coming into contact with a bearing ring to which the bearing seal is attached; and

and a nut that can be screwed to the external thread portion from the opposite side of the ferrule with respect to the support plate portion.