JP2008240957A - Bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device having a durable sealing structure capable of keeping constant sealing performance for a long period of time. <P>SOLUTION: The bearing device A provided with a sealing device 2 for which a static ring 12, a rotating ring 10, a plurality of rolling elements 18, a slinger 22, a core metal 24 and a seal 26 are combined, the slinger consists of a slinger fixing part 22a and a slinger disk part 22b continuing from the slinger and extending out at a predetermined angle. The core metal 24 consists of a core metal fixing part 24a fixed to the static ring and a core metal disk part 24b continuing from the core metal and extending out at a predetermined angle. The seal 26 is provided between the slinger and the core metal and has a plurality of lips 261 which are connected with one of the slinger and the core metal and slide in contact with the other one and a rotary ring. A step part 10d formed by cutting off a recessed shape part of a confronting surface 10a over the whole circumference to press fit and fix the slinger is provided. The slinger is fixed to the rotation ring by fitting the slinger fixing part in a circumferential surface part 10u of the step part and tightly adhering the slinger disk part to a side surface part 10v of the step part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealing structure for keeping the inside of various bearings (for example, a bearing device such as a hub unit bearing (wheel supporting bearing unit) for supporting a wheel of an automobile) in a sealed state. The present invention relates to an improvement in a sealing structure for improving the sealing performance of a wheel support bearing unit.

  Conventionally, the bearing device has been provided with various sealing devices in order to shield the inside of the bearing from the outside and keep it in a sealed state (airtight state and liquid tight state), and by providing the sealing device, Prevents foreign matter (e.g., muddy water, dust, etc.) from entering the bearing device from the outside, and prevents lubricant (e.g., grease, lubricating oil, etc.) enclosed inside from leaking to the outside. It is preventing.

Such a sealing device can be roughly classified into a contact type and a non-contact type. For example, as the contact type, an annular core formed by pressing a steel plate or the like so that the cross section is L-shaped. There is a seal that has a structure in which various elastic materials (for example, resin materials such as rubber and plastic) are connected to a part of gold, and as a non-contact type, it is pressed from a metal plate (steel plate) such as a stainless steel plate or an iron plate. There is a shield formed by processing or the like (see Patent Document 1). Furthermore, a contact-type sealing device (so-called pack seal) having a package structure obtained by combining the contact-type seal and the non-contact-type shield (so-called slinger) so that the cross-sectional shape is substantially box-shaped (rectangular) is also known. (See Patent Document 2).
2B illustrates the configuration of a bearing device (wheel support bearing unit) provided with a pack seal 80 as a contact-type sealing device, and FIG. A configuration of a bearing device with a magnetic sensor (wheel support bearing unit) provided with an encoder core 90 as a mold sealing device is illustrated.

  In general, the contact type has higher sealing performance than the non-contact type, and depending on the level of hermeticity (air tightness and liquid tightness) required according to the usage conditions and purpose of the bearing device Different sealing devices are used.

  As an example, the pack seal has not only the feature that the cross-sectional area is small and compact, and it is not necessary to secure a large installation space, but also an excellent feature that the sealing performance is extremely high and the torque is low. Therefore, a bearing device that requires strict sealing performance (for example, a high level of muddy water intrusion prevention effect), for example, a hub unit bearing (hereinafter referred to as a bearing unit) A for supporting a vehicle wheel as shown in FIG. Widely used as a sealing device against

FIG. 2 (a) shows a configuration example of such a pack seal. The pack seal 2 includes a slinger 42 and a core metal (hereinafter referred to as a seal core metal) arranged to face each other at a predetermined interval. ) 44 and a seal 26 interposed therebetween. In this case, the slinger 22 and the seal core 44 are both formed in an annular shape having a substantially L-shaped cross section, and the seal 46 is connected to the seal core 44 and slid on the slinger 42. A plurality of lip portions 46l that are in contact with each other are provided.
When manufacturing the pack seal 2 having such a configuration, the slinger 42 and the seal core 44 are usually formed by pressing a thin steel plate or the like in consideration of ease of processing and cost. Yes.

  When the pack seal 2 having such a configuration is assembled to the bearing unit A (FIG. 3), the slinger 42 is fixed to the rotating wheel 10 (specifically, the inner ring component 16) (specifically, The seal mandrel 44 is fixed (specifically fitted) to the stationary wheel 12 and is always kept stationary while rotating with the rotating wheel 10 (inner ring component 16). The

By the way, as described above, the pack seal 2 has a feature that it is very compact, but is compact (that is, has a small cross-sectional area), so that the rotary wheel 10 (inner ring configuration) when assembled to the bearing unit A is used. The fitting length between the body 16) and the stationary wheel 12 (the length in the axial direction (left-right direction in FIG. 2)) becomes short, and the fitting force may not be sufficiently secured.
For this reason, metal fitting is performed when the pack seal 2 is assembled to the bearing unit A so that a sufficient fitting force can be obtained even when the fitting length is short.

However, when the pack seal 2 is assembled to the bearing unit A by metal fitting, the slinger 42 is pressed into the rotating wheel 10 (inner ring component 16) and the seal metal core 44 is pressed into the stationary wheel 12. In addition, there is a risk that scratches in the axial direction (left-right direction in FIG. 2) may occur on the fitting surfaces 42s and 44s. Similarly, there is a possibility that scratches in the axial direction may occur on the fitting surface of the rotating wheel 10 (inner ring structure 16) and the fitting surface of the stationary wheel 12.
When the slinger 42 and the seal metal core 44 are formed by the above-described pressing, the fitting surfaces 42s and 44s are scratched in the axial direction (streaks) by the press machine during the forming. Sometimes it ends up.

  If such axial flaws occur on the fitting surfaces 42s, 44s of the slinger 42 and the seal metal core 44, or on the fitting surfaces of the rotating wheel 10 (inner ring component 16) and the stationary wheel 12, bearings There is a case where water enters the damaged part from the outside of the unit A, and for example, the fitting surface of the rotating wheel 10 (inner ring structure 16) or the stationary wheel 12 may rust. If the fitting surfaces of the rotating wheel 10 (inner ring component 16) and the stationary wheel 12 are rusted in this way, the fitting force with the slinger 42 and the seal metal core 44 is reduced, and the sealing performance (infiltration prevention effect) thereof. This also reduces the amount of water entering the bearing unit A from the fitting portion between the slinger 42 and the rotating wheel 10 (inner ring structure 16) or the fitting portion between the seal metal core 44 and the stationary ring 12. There is a risk of it.

In order to avoid such inconveniences, various measures have been taken conventionally.For example, a seal is connected to the outer diameter portion (end portion of the fitting surface) of the seal metal core (for example, vulcanization molding). A method for forming a rubber nose gasket 46g is known. On the other hand, since the slinger 42 is often not vulcanized and a rubber nose gasket 46g cannot be formed like a seal metal core, a rubber-like sealing material is applied to the inner diameter portion (fitting surface). There are known methods for applying such coating.
JP 2006-64082 A Japanese Utility Model Publication No. 6-55808

  However, the quality of the coating with the sealing material tends to be unstable, and the cost for applying such a coating becomes necessary. In addition, when the slinger 42 is press-fitted into the rotating wheel 10 (inner ring structure 16), the coating applied to the inner diameter portion (fitting surface) is easily peeled off, and as a result, sufficient sealing performance (infiltration prevention effect) can be obtained. May become impossible.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a bearing device having a durable sealing structure capable of maintaining a constant sealing performance over a long period of time. There is.

In order to achieve such an object, a bearing device according to the present invention is incorporated into at least a pair of stationary wheels and rotating wheels facing each other so as to be relatively rotatable, and capable of rolling between the stationary wheels and the rotating wheels. In order to keep the inside of the plurality of rolling elements airtight and liquid-tight, a sealing device having a structure in which a slinger, a metal core and a seal are combined is provided.
In such a bearing device, the slinger is continuous with a cylindrical slinger fixing portion extending in a predetermined direction and an extension end on one side of the slinger fixing portion, and extends at a predetermined angle with respect to the slinger fixing portion. The core metal is formed in a cylindrical shape extending in a predetermined direction, and includes a core metal fixing portion fixed to the stationary ring, and one side of the core metal fixing portion. The slinger and the core metal, which are formed of a core metal disk portion that is continuous with the extension end and extends at a predetermined angle with respect to the core metal fixing portion, are arranged to face each other at a predetermined interval. And a plurality of lips extending so as to be in sliding contact with the other and the rotating wheel.
In this case, in order to press-fit and fix the slinger, the rotating wheel is provided with a stepped portion formed by continuously cutting a part of the surface facing the stationary wheel into a concave shape over the entire circumference. The slinger fixing part is fitted to the peripheral surface part of the step part, and the slinger disc part is brought into close contact with the side part of the step part and fixed to the rotating wheel.

  At that time, the slinger is configured by setting the internal angle formed with the slinger fixing part to an obtuse angle so that the slinger disk part is inclined forward in the press-fitting direction with respect to the slinger fixing part. Is elastically deformed in the opposite direction, so that the slinger fixing portion is fitted to the peripheral surface portion of the step portion, and the slinger disk portion is in close contact with the side surface portion of the step portion.

  ADVANTAGE OF THE INVENTION According to this invention, the bearing apparatus which comprises the sealing structure excellent in durability which can maintain fixed sealing performance over a long term can be provided.

  Hereinafter, a bearing device of the present invention will be described with reference to the accompanying drawings. Note that the sealing structure according to the present invention can be applied to shield the inside of various bearing devices from the outside and keep them in a sealed state (airtight state and liquid-tight state). The case where it is applied to seal the inside of a hub unit bearing (bearing unit A) for supporting a vehicle wheel as shown is assumed as an example. In the following description, the wheel side of the automobile (the left side of FIGS. 1A to 1C and FIG. 3) is referred to as the outboard side, and the opposite side, that is, the inside of the automobile body (in the drawings). The right side) is called the inboard side.

  FIG. 3 shows the driving wheels of an automobile (rear wheels of a front engine rear wheel drive (FR) car and rear engine rear wheel drive (RR) car, front wheels of a front engine front wheel drive (FF) car, and four wheels. The configuration of a hub unit bearing that supports a wheel drive (all wheels of a 4WD vehicle) is shown as an example, but the bearing unit is a driven wheel of an automobile (front wheel of FR and RR cars, rear wheel of FF cars). You may comprise as a hub unit bearing which supports.

  The type (type) of the bearing unit is not particularly limited. For example, the presence / absence and number of flanges 14f of the rotating wheel 10 (hub 14), the presence / absence and number of flanges 12f of the stationary ring 12, or the presence / absence of the inner ring component 16 The type of rolling element 18 (balls and various rollers) may be arbitrarily set according to the usage conditions and purpose of the bearing unit. Further, in the configuration shown in FIG. 3, the outer member (outer race ring) is a stationary ring 12, and the inner member (inner race ring) is a rotary wheel 10 (hub 14 and inner ring component 16). In contrast, a bearing unit having a configuration in which the outer member (outer raceway) is a rotating ring and the inner member (inner raceway) is a stationary ring may be used.

The inner ring constituting body 16 is formed with a raceway surface 10t facing the raceway surface 12t on the inboard side of the stationary wheel 12 and is fitted on the inboard side of the hub 14 to constitute the rotating wheel 10 together with the hub 14. It refers to a member.
Also, in any bearing unit, the rotating wheel 10 has a wheel constituent member (for example, a disc wheel (not shown)) fixed and rotated together with the wheel constituent member, whereas the stationary wheel 12 It is fixed to a structural member (for example, a knuckle (not shown) of a suspension device) and kept stationary.

  FIGS. 1A and 1B show a sealing structure of a bearing unit A (FIG. 3) according to an embodiment of the present invention. The bearing unit A is disposed so as to be relatively rotatable. In order to keep the inside of the stationary wheel 12 and the rotating wheel 10, the plurality of rolling elements (balls) 18 incorporated so as to be able to roll between the stationary wheel 12 and the rotating wheel 10, and a slinger 22, a sealing device 2 having a structure in which a core metal 24 and a seal 26 are combined is provided.

  Specifically, the stationary wheel 12 is fixed to a vehicle body constituent member (for example, a knuckle (not shown) of a suspension device) and is always kept in a non-rotating state, whereas the rotating wheel 10 is a wheel constituent member. (For example, a disc wheel (not shown)) is fixed and rotating together with the wheel constituent member, and formed between the stationary wheel 12 and the rotating wheel 10 and facing each other between the raceway surfaces 10s and 12s, and the raceway. A plurality of rolling elements (balls) 18 are assembled so as to be capable of rolling between the surfaces 10t and 12t, thereby forming a bearing unit A.

  In this case, the stationary wheel 12 is integrally formed with a fixing flange 12f that protrudes outward (in the direction of diameter expansion) from the outer peripheral surface 12b, and a fixing bolt is inserted into the fixing hole 12h that passes through the fixing flange 12f. By inserting (not shown) and fastening it to the vehicle body side, the stationary wheel 12 can be fixed to a knuckle of a suspension device (suspension) not shown.

  On the other hand, the rotating wheel 10 is provided with a hub 14 having a substantially cylindrical shape, and the hub 14 is fixed to a disk wheel (not shown) of a wheel via a brake rotor (not shown) of a brake. It is configured to rotate with the disc wheel. Note that a hub flange 14f for fixing (externally fitting) the brake rotor and the disc wheel on the outboard side of the hub 10 is continuously provided along the circumferential direction.

  The hub flange 14f extends outward (in the direction of diameter expansion of the hub 10) beyond the stationary ring 2, and a plurality of through holes (bolt holes) are provided in the vicinity of the extended edge along the circumferential direction. 14h is provided. A brake rotor and a disc wheel (not shown) are each provided with a plurality of through holes (as an example, the same number as the bolt holes 14h) that can communicate with the bolt holes 14h. Then, the brake rotor and the disc wheel can be positioned and fixed with respect to the hub flange 14f by inserting the hub bolt 14b from the bolt hole 14h into the through hole and fastening (tightening) with a hub nut (not shown). it can.

In addition, an annular inner ring structure 16 is externally fitted to the hub 14 on the inboard side. At that time, for example, with a plurality of rolling elements (balls) 18 incorporated between the stationary wheel 12 and the hub 14, the inner ring structure 16 is inserted from the inboard side of the hub 14 and applied to the stepped portion 14s. After that, a crimping portion 14 d is formed by crimping a crimping region provided in advance on the inboard side of the hub 14 along the end surface 16 a on the inboard side of the inner ring component 16. As a result, the inner ring component 16 can be integrated and fixed to the inboard side of the hub 14 while being sandwiched between the caulking portion 14d and the stepped portion 14s, and the bearing unit A (more specifically, Specifically, a predetermined preload can be applied to the rolling elements (balls) 18).
Instead of the above-described caulking and fixing, for example, after the inner ring component 16 is externally fitted to the stepped portion 14s formed on the hub 14, it is tightened by a fastening member such as a nut from the inboard side. The inner ring component 16 may be fixed to the inboard side of the hub 14 in some cases.

In the present embodiment, the case where the sealing device 2 is disposed on the inboard side and the bearing unit A is configured is assumed as an example and will be described below. The bearing unit A is provided with a sealing device (outboard seal) 30 on the outboard side as an example (see FIG. 3).
The slinger 22 is press-fitted and fixed to the rotating wheel 10 (inner ring structure 16), and has a cylindrical fixing portion (hereinafter referred to as a slinger fixing portion) 22a extending in a predetermined direction, and one of the slinger fixing portions 22a. It is composed of a disc portion (hereinafter referred to as a slinger disc portion) 22b that is continuous to the extension end on the side and extends at a predetermined angle with respect to the slinger fixing portion 22a.

  In FIG. 1 (b), a slinger fixing portion 22a is formed in a cylindrical shape extending in a predetermined direction (left and right direction in the figure) with a predetermined length (distance in the same direction in the figure), and a slinger disk portion 22b. Is a predetermined length (the distance in the vertical direction in the figure) with respect to the slinger fixing part 22a, and the diameter-extending direction (continuous to the extension end (left end in the figure) 22t on one side of the slinger fixing part 22a ( The configuration of the slinger 22 formed in an annular flat plate shape (ring plate shape) extending in the upward direction in FIG. In this case, the slinger 22 is disposed between the slinger disc portion 22b and the slinger fixing portion 22a so that the slinger disc portion 22b is tilted forward with respect to the slinger fixing portion 22a in the press-fitting direction (the left direction in the figure). The inner angle formed (angle θ shown in FIG. 1B (hereinafter referred to as the inner angle θ)) is set to an obtuse angle (90 ° <θ <180 °), and the slinger disc portion 22b is an extended end of the slinger fixing portion 22a. The structure is extended from 22t.

  That is, in the state before the slinger 22 is press-fitted into the rotating wheel 10 (inner ring component 16) (the state shown in FIG. 1B), the slinger disc portion 22b is inserted into the slinger fixing portion 22a in the press-fitting direction. Tilt forward. In the slinger 22, the slinger disc portion 22b is elastically deformed in a direction opposite to the press-fitting direction (right direction in the figure), and the slinger disc portion 22b is substantially perpendicular to the slinger fixing portion 22a (that is, the inner angle θ). Is fixed (specifically, fitted) to the rotating wheel 10 (inner ring component 16) (in the state shown in FIG. 5A).

As a result, compared to the case where the slinger 22 is configured by setting the inner angle θ in a state before being press-fitted into the rotating wheel 10 (inner ring structure 16) to a substantially right angle (θ≈90 °), the rotating wheel 10 (inner ring configuration). The slinger disc portion 22b can be more closely attached to the body 16), and the slinger fixing portion 22a can be more strongly fitted. As a result, the slinger 22 has a structure that rotates stably together with the rotating wheel 10 (inner ring component 16).
Note that the specific size of the internal angle θ (90 ° <θ <180 °) may be arbitrarily set according to the material of the slinger 22 and the like, and is not particularly limited here.

  The cored bar 24 has a cylindrical shape extending in a predetermined direction, a fixed part (hereinafter referred to as a cored bar fixing part) 24a fixed to the stationary ring 12, and one side of the cored bar fixing part 24a. It is composed of a disc part (hereinafter referred to as a cored bar part) 24b that is continuous with the extending end and extends at a predetermined angle with respect to the cored bar fixing part 24a.

  In FIG. 1A, a cored bar fixing portion 24a is formed in a cylindrical shape extending in a predetermined direction (left and right direction in the figure) with a predetermined length (distance in the same direction in the figure). The portion 24b has a predetermined length (distance in the vertical direction in the figure) at a substantially right angle to the metal core fixing part 24a, and extends to one extension end (left end in the figure) 24t of the metal core fixing part 24a. The structure of the cored bar 24 formed in an annular flat plate shape (ring plate shape) continuously extending in the diameter reducing direction (downward in the figure) is shown. That is, in this case, the cored bar 24 is configured so that the longitudinal cross-sectional shape is substantially L-shaped, and is press-fitted and fixed (specifically, fitted) to the stationary ring 12 of the bearing unit A. It has a structure that is always kept stationary.

  As an example, a seal 26 is connected (for example, vulcanized) to the end of the cored bar 24 opposite to the extending end 24t of the cored bar fixing part 24a (the right end in FIG. 1A). Thus, a nose gasket 24g is formed. Thereby, the metal core fixing part 24a is brought into close contact with the stationary ring 12, and these fitting parts are kept in a sealed state, for example, effectively preventing water from entering the fitting part from the outside of the bearing unit A. Yes.

  Further, the seal 26 is interposed between the slinger 22 and the cored bar 24 that are arranged to face each other with a predetermined interval, and is connected to one of the slinger 22 and the seal cored bar 24, and the other and the rotating wheel 10. The structure is in sliding contact with the (inner ring structure 16). In the configuration shown in FIG. 1 (a), as an example, the seal 26 includes a core metal fixing portion 24a and a core metal disc portion 24b of the core metal 24 (specifically, the inner surfaces thereof (the lower surface of FIG. A plurality of (for example, three) lips 261 are connected to the slinger 22 (specifically, the surface on the outboard side of the slinger disc portion 22b (hereinafter referred to as the disc inner surface 22u)), and the rotation It extends toward the ring 10 (specifically, the outer peripheral surface 10a) and has a structure provided so as to be in sliding contact with the disk inner surface 22u and the outer peripheral surface 10a.

  In the following description, the lip 26l that is in sliding contact with the disk inner surface 22u of the slinger disk portion 22b is referred to as an axial lip 26a, and the lip 26l that is in sliding contact with the outer peripheral surface 10a of the rotating wheel 10 (inner ring structure 16) is a radial lip 26r. That's it. Furthermore, a lip 26l (a lip located in the middle of the three lips 26l shown in FIG. 1A) located between the axial lip 26a and the radial lip 26r and in sliding contact with the outer peripheral surface 10a is referred to as a main lip 26m.

  As the material of the seal 26, various elastic materials (for example, resin materials such as rubber and plastic) may be arbitrarily selected and applied according to the material of the slinger 22 and the core metal 24. Further, the number and shape of the lips 261 provided on the seal 26 are not limited to the configuration shown in FIG. 1A. For example, two lips 261 (for example, an axial lip 26a and a main lip 26m) are provided on the seal 26. A configuration in which four or more lips 261 are provided may be employed. Furthermore, the core metal 24 and the seal 26 (various elastic materials) may be connected by arbitrarily selecting various methods such as adhesion, caulking, coating, injection molding, and vulcanization molding.

  The form of the seal 26 is not particularly limited to the configuration shown in FIG. 1 (a). For example, the seal has two divided configurations, one is connected to a slinger, and the other is connected to a core bar, It is good also as a structure which makes the seal | sticker connected to slidably contact with a metal core, and makes the seal | sticker connected with the metal core slidably contact with a slinger.

  In this embodiment, in order to press-fit and fix the slinger 22 to the rotating wheel 10 (inner ring structure 16), a part (inboard) of the surface facing the stationary wheel 12 (the outer peripheral surface 10a of the rotating wheel 10). A step portion 10d is formed by continuously cutting the end portion on the side (the right end portion in FIG. 1A) into a concave shape over the entire circumference. The slinger 22 has a slinger fixing portion 22a (specifically, an inner peripheral surface (hereinafter referred to as a fixed fitting surface) 22s) as a peripheral surface portion (hereinafter referred to as a step portion peripheral surface) 10u of the step portion 10d. At the same time, the slinger disc portion 22b (specifically, the disc inner surface 22u) is brought into close contact with the side surface portion (hereinafter referred to as the step portion side surface) 10v of the step portion 10d, so that the rotating wheel 10 (inner ring constituent body). 16).

  In this case, the size (width and depth) of the step portion 10d, that is, the width of the step portion peripheral surface 10u (the distance in the left-right direction in FIG. 1 (a)) and the height of the step portion side surface 10v (up and down in the figure). The distance in the direction) and the shapes thereof are not particularly limited, and may be arbitrarily set according to the size and shape of the slinger 22 or the size and shape of the rotating wheel 10 (inner ring structure 16), for example.

As an example, in the configuration shown in FIG. 1A, the width of the stepped portion 10d (the width of the stepped peripheral surface 10u) is the extension length of the slinger fixing portion 22a of the slinger 22 (the distance in the left-right direction in FIG. 1). The depth (height of the stepped portion side surface 10v) is set to a size smaller than the extending length of the slinger disc portion 22b (the vertical distance in the figure). Has been.
In addition, in the configuration shown in FIG. 1A, the stepped portion 10d is, as an example, more specifically, a stepped peripheral surface 10u and a stepped portion side surface 10v so that the contour shape of the vertical cross section forms a rectangular shape. Are continuous at substantially right angles.

  By adopting such a configuration, when the slinger 22 is press-fitted and fixed to the stepped portion 10d, the end of the slinger fixing portion 22a opposite to the extension end 22t (inboard side) (the right end of FIG. 1A) The portion (hereinafter referred to as the tip portion) 22w can be positioned in a state where it is recessed toward the outboard side from the end surface 10c on the inboard side of the rotating wheel 10 (inner ring structure 16). If it grasps another way, the whole slinger fixing | fixed part 22a can be arrange | positioned to the step part 10d. On the other hand, the slinger disc portion 22b can be positioned in a state of projecting in the direction of the stationary wheel 12 (upward in the figure) from the outer peripheral surface 10a of the inner ring 10 (inner ring structure 16).

  Thereby, the contact area (fitting area) of the slinger fixing part 22a of the slinger 22 and the step part 10d (step part peripheral surface 10u) of the rotating wheel 10 (inner ring structure 16) can be increased. Thus, the fitting force to the rotating wheel 10 (inner ring constituting body 16) can be increased.

  Further, the fitting position between the slinger 22 and the rotating wheel 10 (inner ring component 16), more specifically, the fitting between the fixed fitting surface 22s of the slinger fixing portion 22a and the stepped peripheral surface 10u of the stepped portion 10d. The position in the radial direction (the distance corresponding to the depth of the stepped portion 10d (the height of the stepped portion side surface 10v) with respect to the outer peripheral surface 10a of the rotating wheel 10 (inner ring constituting body 16) with which the lip 26l of the seal 26 is in sliding contact. It can be shifted in the vertical direction in FIG. 1A (downward in the figure).

  Therefore, the slinger disc portion 22b of the slinger 22 is configured to cover and close the sliding contact portion between the lip 261 and the outer peripheral surface 10a, and the sliding contact portion is not directly exposed to the outside of the bearing unit A. The part can be shielded from the outside of the unit. As a result, foreign matter (for example, muddy water, dust, etc.) from the outside of the bearing unit A can be reliably prevented, and the inside of the unit can always be kept sealed.

  Further, the slinger 22 and the rotating wheel 10 (inner ring structure 16) are configured such that the fixed fitting surface 22s of the slinger fixing portion 22a is fitted to the stepped peripheral surface 10u of the stepped portion 10d, and the slinger disc portion 22b Since the disc inner surface 22u is configured to be in close contact with the stepped portion side surface 10v of the stepped portion 10d, the contact range (sealing range) between the slinger 22 and the rotating wheel 10 (inner ring constituting body 16) is expanded. be able to.

  Therefore, it is possible to prevent rusting on the stepped portion peripheral surface 10u and the stepped portion side surface 10v, and even if rusted, the progress thereof can be significantly delayed. Thus, the fitting state between the fixed fitting surface 22s and the stepped portion peripheral surface 10u and the close contact state between the disk inner surface 22u and the stepped portion side surface 10v can be kept constant over a long period of time. It can continue to be kept sealed.

  It should be noted that, in the unlikely event, water has been immersed from the outside of the bearing unit A through the fitting portion between the fixed fitting surface 22s and the stepped portion peripheral surface 10u and the close contact portion between the disk inner surface 22u and the stepped portion side surface 10v. However, the water will be submerged in front of the main lip 26m (on the right side of the main lip 26m in FIG. 1 (a)), and then the water will be submerged into the inside of the unit. Furthermore, the radial lip 26r can surely prevent this.

  In addition, since the slinger 22 is fixed to the rotating wheel 10 (inner ring component 16) with the slinger disk portion 22b in close contact with the stepped portion side surface 10v, the assembly of the sealing device 2 to the bearing unit A is It is also possible to prevent the sealing device 2 (slinger 22) from moving (i.e., misaligned) in the inner direction of the bearing unit A (the left direction in FIG. 1A).

  In this case, the size (extension length, thickness (distance in the vertical direction in FIG. 1A) and diameter, etc.) of the slinger fixing portion 22a, and the size (extension of the slinger disc portion 22b). Since the protruding length, thickness (distance in the left-right direction in the figure) and diameter and other dimensions) are arbitrarily set according to the size and shape of the step portion 10d of the rotating wheel 10 (inner ring structure 16). There is no particular limitation here. For example, the slinger disc portion 22b may be set to an extension length that allows the disc inner surface 22u to be in sliding contact with the axial lip 26a of the seal 26 in a state where the slinger 22 is fixed to the step portion 10d. .

  However, when the slinger 22 is fixed to the stepped portion 10d, the slinger fixing portion 22a is positioned in a state where the tip portion 22w is recessed toward the outboard side from the end surface 10c of the rotating wheel 10 (inner ring component 16). It is necessary to set the extension length in advance so as to be possible. The reason will be described below.

  As described above, since the bearing unit A is configured as a hub unit bearing that supports driving wheels of an automobile, the hub 14 has an axial direction from one end to the other end (from the left end to the right end in FIG. 3). A spline hole 14t having a predetermined size is formed so as to pass through (to the side), and a spline shaft of a constant velocity joint (hereinafter referred to as CVJ) (not shown) is inserted into the spline hole 14t.

  Such a CVJ (spline shaft) is very hard, and the contact portion between the CVJ and the bearing unit A, specifically, the peripheral surface of the spline shaft and the peripheral surface of the spline hole 14t of the hub 14 are in contact with the spline shaft 50s. Between the rotating wheel 10 (hub 14) and the stationary wheel 12 due to a load caused by an axial force (axial force) and various loads (radial load, axial load, moment load, etc.) applied while the vehicle is running. The load generated by the relative inclination of the two acts in a superimposed manner. At that time, a so-called stick-slip phenomenon may occur, and a member made of a steel plate like the slinger 22 may be deformed (elongated and deformed) in a direction in which the member is elongated.

  Accordingly, the slinger 22 is positioned (disposed on the stepped portion 10d) by positioning the slinger 22 in a state in which the tip end portion 22w of the slinger fixing portion 22a is recessed toward the outboard side from the end surface 10c of the rotating wheel 10 (inner ring constituent body 16). Even if the slinger 22 (specifically, the slinger fixing portion 22a) is extended and deformed, it is possible to avoid the tip portion 22w of the slinger fixing portion 22a from protruding from the end face 10c. Thereby, for example, it is possible to effectively prevent the occurrence of inconvenience such as contact of the distal end portion 22w of the slinger fixing portion 22a with the crimping portion 14d formed on the hub 14.

  Further, the material and forming method of the slinger 22 are not particularly limited. For example, the slinger 22 is made of a predetermined metal plate (for example, a steel plate having rigidity and elasticity), and the metal plate (steel plate) is pressed. What is necessary is just to form. As an example, when the slinger 22 is made of stainless steel, rusting on the disc inner surface 22u of the slinger disc portion 22b, which is a slidable contact surface with the lip 261 of the seal 26, is prevented, and sliding with the disc inner surface 22u is prevented. It is possible to effectively prevent the lip 26l from being damaged at the time of contact.

  In the sealing device 2 according to this embodiment described above, the slinger 22 is fitted to the rotating wheel 10 (inner ring structure 16) with respect to the inner diameter dimension (specifically, the inner diameter dimension of the slinger fixing portion 22a). It is configured to provide a fitting allowance when making it. That is, the slinger 22 has an inner diameter dimension of the slinger fixing portion 22a that is larger than an outer diameter dimension of the rotating wheel 10 (inner ring structure 16) (specifically, a diameter dimension of the step portion peripheral surface 10u of the step portion 10d). The size is set to be smaller by the amount of the fitting allowance. At that time, the fitting allowance to be set in the slinger fixing portion 22a of the slinger 22 may be arbitrarily set according to the size of the rotating wheel 10 (inner ring structure 16).

  On the other hand, the cored bar 24 is configured by providing a fitting allowance for fitting to the stationary wheel 12 with respect to the outer diameter dimension (specifically, the outer diameter dimension of the cored bar fixing portion 24a). Yes. That is, the outer diameter of the cored bar fixing part 24a is equal to the inner diameter of the stationary ring 12 (specifically, the step 12d where the stationary ring 12 is fitted (contacted) with the cored bar fixing part 24a). (Diameter dimension of the peripheral surface portion) is set so as to be larger than the fitting allowance. At this time, the fitting allowance to be set in the core metal fixing portion 24a of the core metal 24 may be arbitrarily set according to the size of the stationary ring 12 and the like.

  In the configuration shown in FIG. 1 (a), as an example, in order to press-fit and fix the cored bar 24 to the stationary ring 12, the surface facing the rotating wheel 10 (inner ring component 16) (stationary ring). A step portion 12d is provided in which a part (the end portion on the inboard side (the right end portion in the figure)) of the inner peripheral surface 12a of 12 is continuously cut out in a concave shape over the entire circumference. The cored bar 24 has a cored bar fixing part 24a (specifically, the outer peripheral surface thereof) fitted to the peripheral surface part of the stepped part 12d and a cored bar disk part 24b (specifically, an outboard). 1 (the left side in FIG. 1A) is fixed to the stationary wheel 12 with a predetermined distance from the side surface portion (the left side portion in the figure) of the stepped portion 12d. For example, the core metal 24 may be directly fitted and fixed to the inner peripheral surface 12a without providing the step 12d as described above.

  Here, the size (extension length and thickness (distance in the vertical direction in FIG. 1A)) of the core metal fixing portion 24a and the size (extension of the core metal disc portion 24b). The length, thickness (distance in the left-right direction in the figure) and diameter and other dimensions) are, for example, the size and shape of the stationary wheel 12 of the bearing unit A, or the size and shape of the step portion 12d of the stationary wheel 12. Since it is arbitrarily set according to the above, it is not particularly limited. In addition, the inclination angle of the cored bar part 24b with respect to the cored bar fixing part 24a is not particularly limited, and may be arbitrarily set according to the use conditions of the sealing device 2 and the like. Further, the material and forming method of the core metal 24 are not particularly limited. For example, the core metal 24 is made of a predetermined metal plate (for example, a steel plate that can be vulcanized with an elastic material such as rubber), and the metal plate What is necessary is just to form by pressing a (steel plate).

As described above, according to the present embodiment, it is possible to maintain a constant sealing performance (for example, muddy water intrusion prevention effect) over a long period of time, and easily realize a bearing device sealing structure with excellent durability. can do.
Therefore, by applying such a sealing structure, the bearing unit A can be stably rotated with a certain accuracy over a long period of time.

  In the sealing device 2 according to this embodiment described above, as shown in FIG. 1 (a), the slinger disc portion 22b of the slinger 22 is formed in a flat surface shape (longitudinal section) from the extending end 22t of the slinger fixing portion 22a. However, the configuration of the sealing device 2 (the slinger disc portion 22b of the slinger 22) is not particularly limited to such a flat surface shape. For example, as in the first modification of the present invention shown in FIG. 1 (c) and the second modification of the present invention shown in FIG. 1 (d), the sealing device 2 (slinger 2) has a slinger disc portion 22b as a stepped structure. 22) may be configured, and the same effect can be obtained even when these configurations are used.

  Hereinafter, the first modification and the second modification will be described. In this case, the sealing device 2 (slinger 22) according to the first modification and the second modification has the same basic configuration as that of the above-described embodiment except that the slinger disk portion 22b has a stepped structure. Since it is the same as that of the sealing device 2 (FIG. 1 (a), (b)) which concerns, these are not demonstrated in particular. At this time, members having the same configuration are denoted by the same reference numerals in the drawings as necessary.

  In the first modified example of the present invention shown in FIG. 1C, the slinger 22 is configured as a stepped structure in which the slinger disc portion 22b protrudes in a convex shape toward the inboard side (the right side in the figure). Yes. In this case, the slinger disc part 22b is composed of three parts: a close contact part b1, a connecting part b2, and a sliding contact part b3. Specifically, an inner angle θ (see FIG. 1B) is formed from the extending end 22t of the slinger fixing portion 22a, and the depth (step portion side surface) of the step portion 10d of the rotating wheel 10 (inner ring structure 16) is formed. After the close contact portion b1 is extended with approximately the same dimension as the height of 10v (distance in the vertical direction in FIG. 10C), the contact portion b1 is substantially perpendicular to the inboard side (right side in the same drawing). The connecting portion b2 is extended by a predetermined length, and the sliding contact portion b3 is extended from the connecting portion b2 by a predetermined length at a substantially right angle in the diameter increasing direction, thereby forming a slinger disc portion 22b.

  FIG. 1C shows a state after the sealing device 2 (slinger 22) is press-fitted into the step portion 10d of the rotating wheel 10 (inner ring component 16). In this state, the slinger The disc portion 22b is elastically deformed in a direction opposite to the press-fitting direction (right direction in the figure) so that the contact portion b1 is substantially perpendicular to the slinger fixing portion 22a, and the contact portion b1 is transformed into the step portion 10d. The step portion side surface 10v is closely attached. In this state, the connecting portion b2 (specifically, the outer peripheral surface thereof) is positioned so as to be substantially flush with the outer peripheral surface 10a of the rotating wheel 10 (inner ring constituent body 16). Further, the sliding contact portion b3 (specifically, the surface on the inboard side (the surface on the right side in FIG. 1C)) is substantially the same as the end surface on the inboard side of the stationary wheel 12 (the right end surface in the figure). It is positioned so that it is flush.

By adopting such a configuration, it is possible to increase the spacing between the slinger 22 and the cored bar 24 and increase the size of the seal 26 (lip 26l), and the sealing performance of the sealing device 2 (for example, muddy water intrusion) Prevention effect and the like) can be further enhanced.
However, the configuration of the slinger disc portion 22b (the close contact portion b1, the connecting portion b2, and the sliding contact portion b3) is not limited to the configuration shown in FIG. 1C, and the close contact portion b1, the connecting portion b2, and the sliding contact portion. What is necessary is just to set arbitrarily the magnitude | size (extension length, thickness, etc.), shape, etc. of b3 according to the arrangement position of the sealing apparatus 2, or the magnitude | size, shape, etc. of the seal | sticker 26, for example.

  On the other hand, in the second modified example of the present invention shown in FIG. 1 (d), the slinger 22 is formed as a stepped structure in which the slinger disc portion 22b protrudes to the outboard side (left side in the figure). Is configured. Also in this case, the slinger disc part 22b is comprised by three parts, the contact | adherence part b1, the connection part b2, and the sliding contact part b3. Specifically, an inner angle θ (see FIG. 1B) is formed from the extending end 22t of the slinger fixing portion 22a, and the depth (step portion side surface) of the step portion 10d of the rotating wheel 10 (inner ring structure 16) is formed. After the close contact portion b1 is extended with the same dimension as the height of 10v (the vertical distance in FIG. 10D), the contact portion b1 extends from the close contact portion b1 to the outboard side (left side in the same drawing) at a substantially right angle. The connecting portion b2 is extended by a predetermined length, and the sliding contact portion b3 is extended from the connecting portion b2 by a predetermined length at a substantially right angle in the diameter increasing direction, thereby forming a slinger disc portion 22b.

  FIG. 1 (d) shows a state after the sealing device 2 (slinger 22) is press-fitted into the step portion 10d of the rotating wheel 10 (inner ring component 16). In this state, the slinger The disc portion 22b is elastically deformed in a direction opposite to the press-fitting direction (right direction in the figure) so that the contact portion b1 is substantially perpendicular to the slinger fixing portion 22a, and the contact portion b1 is transformed into the step portion 10d. The step portion side surface 10v is closely attached. In this state, the connecting portion b2 (specifically, the inner peripheral surface thereof) is positioned so as to abut (fit) the outer peripheral surface 10a of the rotating wheel 10 (inner ring constituent body 16). Further, the sliding contact portion b3 (specifically, the surface on the inboard side (the surface on the right side in FIG. 1C)) is more than the end surface on the inboard side of the stationary wheel 12 (the right end surface in the figure). It is positioned so as to be recessed toward the outboard side.

With this configuration, the slinger 22 can be fitted to the rotating wheel 10 (inner ring structure 16) at the connecting portion b2 of the slinger disc portion 22b in addition to the slinger fixing portion 22a. The fitting force to the 22 rotating wheels 10 (inner ring structure 16) can be further increased.
However, the configuration of the slinger disc portion 22b (the close contact portion b1, the connecting portion b2, and the slidable contact portion b3) is not limited to the configuration shown in FIG. 1D, and the close contact portion b1, the connected portion b2, and the slidable contact portion. What is necessary is just to set arbitrarily the magnitude | size (extension length, thickness, etc.), shape, etc. of b3 according to the arrangement position of the sealing apparatus 2, or the magnitude | size, shape, etc. of the seal | sticker 26, for example.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structural example of the sealing structure of the bearing apparatus which concerns on this invention, Comprising: (a) is principal part sectional drawing which shows the state by which the sealing apparatus was assembled | attached, (b) is a structure of a slinger. Sectional drawing which shows, (c) is principal part sectional drawing which shows the sealing structure of the bearing apparatus which concerns on a 1st modification, (d) is principal part sectional drawing which shows the sealing structure of the bearing apparatus which concerns on a 2nd modification. It is a figure for demonstrating the sealing structure of the conventional bearing apparatus, Comprising: (a) is sectional drawing which shows the structural example of a sealing device (pack seal), (b) is a sealing device (pack seal) assembled | attached. FIG. 4C is a cross-sectional view of a main part of the bearing device in which a sealing device (encoder core) is assembled. The principal part sectional drawing which shows the structure of the bearing unit for wheel support (hub unit bearing).

Explanation of symbols

2 Sealing device 10 Rotating wheel 10a Outer peripheral surface (opposite surface)
10d Step portion 10u Step portion peripheral surface 10v Step portion side surface 12 Stationary wheel 14 Hub 16 Inner ring structure 22 Slinger 22a Slinger fixing portion 22b Slinger disc portion 22s Fixing fitting surface 24 Core metal 24a Core metal fixing portion 24b Core metal disc Part 26 Seal 26l (26a, 26m, 26r) Lip A Bearing unit (hub unit bearing)
θ Interior angle

Claims (2)

To keep at least a pair of stationary wheels and rotating wheels opposed to each other so that they can rotate relative to each other, a plurality of rolling elements that can be rolled between the stationary wheels and the rotating wheels, and an airtight and liquid-tight interior. A bearing device comprising a sealing device having a structure in which a slinger, a cored bar and a seal are combined,
The slinger is a cylindrical slinger fixing portion extending in a predetermined direction, and a slinger disc that is continuous with the extending end on one side of the slinger fixing portion and extends at a predetermined angle with respect to the slinger fixing portion. As well as
The cored bar has a cylindrical shape extending in a predetermined direction, and is continuous with the cored bar fixing part fixed to the stationary ring and the extending end on one side of the cored bar fixing part, and the cored bar fixing part Consists of a cored bar part extending at a predetermined angle with respect to
The seal is interposed between the slinger and the cored bar arranged to face each other at a predetermined interval, and is connected to one of the slinger and the cored bar and extends so as to be in sliding contact with the other and the rotating wheel. A plurality of lips,
In order to press-fit and fix the slinger, the rotating wheel is provided with a stepped portion formed by continuously cutting a part of the surface facing the stationary wheel into a concave shape over the entire circumference. A bearing device, wherein a slinger fixing portion is fitted to a peripheral surface portion of the step portion, and the slinger disk portion is closely attached to a side surface portion of the step portion and fixed to the rotating wheel.   The slinger is configured by setting the inner angle formed between the slinger disc portion and the slinger fixing portion to an obtuse angle so that the slinger disc portion tilts forward in the press-fitting direction with respect to the slinger fixing portion. The slinger fixing part is fitted to the peripheral surface part of the step part by being elastically deformed in a direction opposite to the direction, and the slinger disk part is in close contact with the side part of the step part. The bearing device according to claim 1, wherein

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