JP2008115982A - Seal structure and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive seal structure using an easy method for surely sealing the inside of a bearing from the outside of the bearing, and to provide its manufacturing method. <P>SOLUTION: The seal structure is laid between bearing rings for sealing the inside of the bearing from the outside of the bearing. It comprises a slinger 20 to be fitted to one bearing ring, and a seal body to be fitted to the other bearing ring in slide contact with the slinger. The slinger has a cylindrical slinger base portion 20a having a side peripheral face M3 formed fittable to the fitted face of one bearing ring, and an annular slinger wall portion 20b turned around from the slinger base portion toward the other bearing ring. At least the side peripheral face of the slinger base portion out of the whole surface of the slinger is covered with a thermosetting resin J. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a seal structure for sealing the inside of a bearing from the outside of the bearing and a manufacturing method thereof.

  2. Description of the Related Art Conventionally, various vehicles such as automobiles and railways use a bearing that rotatably supports the axle, and the bearing is provided with various seal structures for sealing the inside of the bearing from the outside of the bearing. Yes. As an example, FIG. 1 (a) shows a bearing unit for a drive wheel. The bearing unit is fixed to the vehicle body side and is always kept in a non-rotating state. A rotating wheel (inner ring) 4 provided opposite to the inner side of the wheel 2 and connected to the wheel side and rotating together with the wheel, and a stationary wheel 2 and the rotating wheel 4 can be rotated in a double row (for example, two rows). And a plurality of rolling elements 6 and 8 incorporated in the bearing, and between the stationary wheel 2 and the rotating wheel 4, a seal structure for sealing the inside of the bearing from the outside of the bearing (the lip seal 10a on the wheel side, A pack seal 10b) on the vehicle body side is provided.

  The stationary ring (outer ring) 2 is integrally formed with a fixing flange 2a protruding outward from the outer peripheral side thereof, and a fixing bolt (not shown) is inserted into the fixing hole 2b of the fixing flange 2a. The stationary wheel 2 can be fixed to a suspension device (knuckle) (not shown). On the other hand, the rotating wheel (inner ring) 4 is provided with a substantially cylindrical hub (spindle) 12 that rotates together with, for example, a disk wheel (not shown) of an automobile, and the hub 12 has a disk wheel. A fixed hub flange 12a is projected.

  The hub flange 12a extends outward (outward in the radial direction of the hub 12) beyond the stationary ring (outer ring) 2, and is arranged at predetermined intervals along the circumferential direction in the vicinity of the extended edge. A plurality of hub bolts 14 are provided. In this case, by inserting a plurality of hub bolts 14 into bolt holes (not shown) formed in the disc wheel and tightening with hub nuts (not shown), the disc wheel can be positioned and fixed with respect to the hub flange 12a. it can. At this time, positioning in the radial direction of the wheel is performed by a pilot portion 12d protruding from the wheel side of the hub 12.

  The hub 12 (rotating wheel 4) is fitted (externally fitted) with an annular rotating wheel constituting body 16 (an inner ring constituting the rotating wheel 4 together with the hub 12) on the fitting surface 4n on the vehicle body side. It has become. In this case, for example, in a state where the rolling elements 6 and 8 are held by the cage 18 between the stationary wheel 2 and the rotating wheel 4, the rotating wheel component 16 is fitted to the step portion 12b formed on the fitting surface 4n. After the fitting (external fitting), the caulking region 12c at the end of the hub 12 on the vehicle body side is plastically deformed, and the caulking region 12c is caulked (adhered closely) along the peripheral end 16s of the rotating wheel constituting body 16. Thus, the rotating wheel component 16 can be fixed to the rotating wheel 4 (hub 12).

  In the seal structure provided in such a bearing unit, the lip seal 10a is fixed to the fixed surface 2n-1 on the wheel side of the stationary wheel 2 and is against the sliding surface 4n-1 of the rotating wheel 4 (hub 12). And is slidably positioned. On the other hand, the pack seal 10b is slidably positioned between the stationary surface 2n-2 on the vehicle body side of the stationary wheel 2 and the rotating wheel component 16 (see, for example, Patent Document 1). Specifically, the rotating wheel constituting body 16 is formed with a fitting surface 16m facing the fixed surface 2n-2 of the stationary wheel 2, and the pack seal 10b includes the fitting surface 16m and the fixed surface. 2n-2 is positioned in a fitted state.

Here, the pack seal 10b will be described.
As shown in FIG. 1B, the pack seal 10b includes a slinger 20 fitted to the fitting surface 16m of the rotating wheel constituting body 16, and a seal body fitted to the fixed surface 2n-2 of the stationary wheel 2. It consists of and. Here, the seal body is configured by vulcanizing the seal material 24 on the inner peripheral surface of the mandrel 22 (the surface facing the slinger 20). The seal material 24 includes, for example, three seal lips 24a and 24b. 24c is integrally formed. The mandrel 22 includes a hollow cylindrical portion 22a fitted to the fixed surface 2n-2, and an annular folded portion 22b folded from the hollow cylindrical portion 22a toward the rotating wheel constituting body 16 (fitting surface 16m). It is configured with.

  On the other hand, the slinger 20 is folded toward the stationary ring 2 (fixed surface 2n-2) from the cylindrical slinger base portion 20a fitted to the fitting surface 16m of the rotating wheel constituting body 16 and the slinger base portion 20a. An annular slinger wall portion 20b is provided. In this case, the seal lips 24a, 24b, 24c formed on the seal material 24 are in sliding contact with the annular slinger surfaces M1, M2 of the slinger 20, respectively. One annular slinger surface M1 is formed on the inner periphery of the slinger wall portion 20b (a peripheral surface facing the seal body), and the other annular slinger surface M2 is the inner periphery of the slinger base portion 20a (the seal body facing the seal body). (Peripheral surface).

  According to such a pack seal 10b, for example, the two seal lips 24a, 24b are always in sliding contact with the annular slinger surfaces M1, M2 while the outer inner rings 2, 4 are rotating relative to each other or in a non-rotating state. A labyrinth is formed between the remaining seal lip 24c and the annular slinger surface M2. As a result, the inside of the bearing can be sealed from the outside of the bearing, so that it is possible to prevent the lubricant from leaking to the outside of the bearing and to prevent foreign matters (for example, water and dust) from entering the inside of the bearing. As the sealing material 24, for example, an elastic material such as rubber or elastomer can be applied, and as a method of adding the sealing material 24 to the inner peripheral surface of the mandrel 22, it is added by, for example, baking or an adhesive. Just do it.

  By the way, the pack seal 10b is fitted between the fitting surface 16m of the rotating wheel constituting body 16 and the fixed surface 2n-2 of the stationary wheel 2, so that depending on the fitting force at that time, the mandrel 22 (hollow The fitting surfaces between the cylindrical portion 22a) and the fixed surface 2n-2 and the fitting surfaces between the slinger 20 (slinger base portion 20a) and the fitting surface 16m may be damaged. In this case, depending on the extent of the damage, the sealed state between the inside of the bearing and the outside of the bearing is lowered, and as a result, the lubricant may leak to the outside of the bearing or foreign matter may enter the inside of the bearing.

  Therefore, as a sealing measure for this purpose, for example, as shown in FIG. 1C, a seal is applied to the end 22c of the mandrel 22 (hollow cylindrical portion 22a) (the end opposite to the annular folded portion 22b). A method of forming a nose casket 26 with a material 24 is known. The nose casket 26 is formed by turning a sealing material 24 so as to cover the end 22c of the mandrel 22 on the vehicle body side, and a part of the nose casket 26 protrudes toward the stationary wheel 2 (fixed surface 2n-2). The shape is made. Thereby, even if the fitting surfaces are damaged when the pack seal 10b is fitted between the fitting surface 16m and the fixed surface 2n-2, the sealing performance of the fitting portion is made constant by the nose casket 26. Can be maintained.

On the other hand, as a sealing measure between the slinger 20 (slinger base 20a) and the fitting surface 16m, for example, a sealing material containing a rubber material is applied to the slinger 20, or the slinger 20 (slinger base 20a). There is known a method in which an annular sealing member is interposed between the fitting surface 16m and the fitting surface 16m. However, in recent years, there has been a demand for further cost reduction of the seal structure. However, the method as described above has a limit in reducing its manufacturing cost because it takes time and effort to perform troublesome processing. .
JP 2001-255337 A

  The present invention has been made to meet such demands, and an object of the present invention is to provide a low-cost seal structure capable of reliably sealing the inside of the bearing from the outside of the bearing by a simple method and a method for manufacturing the same. There is.

  In order to achieve such an object, the present invention is a seal structure that is interposed between bearing rings and seals the inside of the bearing from the outside of the bearing, and includes a slinger fitted to one of the bearing rings and the other raceway. A slender body fitted with a ring and slidably in contact with the slinger, and the slinger includes a cylindrical slinger base formed with a side peripheral surface that can be fitted to a fitting surface of one of the race rings, and a slinger base An annular slinger wall portion folded back toward the other race ring is provided, and at least a side peripheral surface of the slinger base portion of the entire surface of the slinger is covered with a thermosetting resin.

  Further, the present invention is a method for producing the above-described seal structure, the step of immersing at least the side surface of the slinger base in a thermosetting resin stored in the tank, and after lifting the slinger from the tank, A process of forming a resin layer having a predetermined film thickness on the side peripheral surface of the slinger base by surplus thermosetting resin being scattered and temporarily dried by vibrating the slinger, and the slinger on which the resin layer is formed And performing a heat treatment at a predetermined temperature.

  According to the present invention, it is possible to realize a low-cost seal structure capable of reliably sealing the inside of a bearing from the outside of the bearing by a simple method and a manufacturing method thereof.

Hereinafter, a seal structure according to an embodiment of the present invention will be described with reference to the accompanying drawings.
Since the present embodiment is an improvement of the above-described seal structure (FIGS. 1A to 1C), only the improved portion will be described below.
In the seal structure of the present embodiment, among the entire surface of the slinger 20, at least the side peripheral surface M3 of the slinger base portion 20a is covered with the thermosetting resin J. FIG. 1 (d) shows a configuration in which the entire surface of the slinger 20 is coated with a thermosetting resin J as an example.

  As the thermosetting resin J, for example, an epoxy resin, a thermosetting resin containing a rubber adhesive, or the like can be applied, but even other resins are excellent in heat resistance and durability. Any resin can be applied. The film thickness of the resin layer formed on the slinger 20 (side peripheral surface M3 of the slinger base 20a) by coating the thermosetting resin J is, for example, an optimum thickness depending on the purpose of use and the use environment of the seal structure. Therefore, the numerical value is not particularly limited here.

Here, an example of a method of coating the thermosetting resin J on the slinger 20 (side peripheral surface M3 of the slinger base portion 20a) will be described.
First, the slinger 20 is immersed in a thermosetting resin J stored in a tank (not shown). Next, after the slinger 20 is pulled up from the tank, the surging thermosetting resin J is scattered and temporarily dried by vibrating the slinger 20 (for example, drying at room temperature), and a predetermined surface is formed on the entire surface of the slinger 20. A resin layer having a film thickness is formed. Then, the slinger 20 on which the resin layer is formed is set in a baking furnace and subjected to heat treatment at a predetermined temperature (for example, 200 ° C. or less). Thereby, the whole surface of the slinger 20 can be covered with the thermosetting resin J.

  When only the side peripheral surface M3 of the slinger base 20a is covered with the thermosetting resin J, only the side peripheral surface M3 of the slinger base 20a may be immersed in the thermosetting resin J stored in the tank. Since the subsequent processing is the same as described above, the description thereof is omitted. Further, the frequency (frequency) at which the slinger 20 is vibrated is arbitrarily set according to the amount of resin adhering when the slinger 20 is immersed in the thermosetting resin J, and is not particularly limited here.

  As described above, according to the seal structure of the present embodiment, at least the side peripheral surface M3 of the slinger base 20a is covered with the thermosetting resin J, so that the pack seal 10b is stationary with the fitting surface 16m of the rotating wheel component 16. When fitting between the fixed surface 2n-2 of the ring 2, the fitting surfaces between the side peripheral surface M3 of the slinger 20 (slinger base 20a) and the fitting surface 16m of the rotating wheel constituting body 16 are There is no direct contact. That is, since the thermosetting resin J is interposed between the side peripheral surface M3 and the fitting surface 16m, it is possible to prevent a situation in which the fitting surfaces are directly touched and damaged. The sealing property of the joint portion can be kept constant. Thereby, the inside of a bearing can be reliably sealed from the outside of a bearing.

  Further, according to the manufacturing method of the seal structure of the present embodiment, the resin layer made of the thermosetting resin J having excellent durability and stable film thickness can be formed. When the side peripheral surface M3 of the base portion 20a) is fitted to the fitting surface 16m of the rotating wheel constituting body 16, the thermosetting resin J is not peeled off and the joint surfaces do not directly touch each other. Thereby, the sealing performance of the fitting portion can be kept constant.

  Furthermore, according to the manufacturing method of the sealing structure of the present embodiment, the thermosetting resin J containing the rubber adhesive of the sealing material 24 can be used. In this case, the step of immersing the slinger 20 The process until the sealing material 24 is vulcanized on the mandrel 22 can be used as it is, and the baking furnace can be used as the secondary vulcanizing furnace for the sealing material 24 as it is. As a result, the resin layer made of the thermosetting resin J can be formed on the entire surface of the slinger 20 (at least the side peripheral surface M3 of the slinger base 20a) without introducing new equipment. Thereby, it becomes possible to reduce the manufacturing cost of the seal structure.

  Further, in the above-described embodiment, before the slinger 20 is immersed in the thermosetting resin tank, the entire surface of the slinger 20 is subjected to chemical conversion treatment with, for example, phosphoric acid, or the roughness is adjusted by tumbler processing or the like. You may do it. By doing so, a resin layer made of the thermosetting resin J can be more stably formed on the entire surface of the slinger 20 (at least the side peripheral surface M3 of the slinger base portion 20a).

  In the above-described embodiment, even when the resin layer made of the thermosetting resin J is also coated on the annular slinger surfaces M1, M2, the ringer surfaces M1, M2 are slid against the seal lips 24a, 24b, 24c. Needless to say, it functions effectively as a moving surface.

  Further, in the above-described embodiment, the arrangement of the seal structure (pack seal 10b) is reversed upside down so that the slinger 20 is fitted to the fixed surface 2n-2 of the stationary wheel 2, and the seal body is the rotating wheel component 16. Even if it is the structure fitted to the fitting surface 16m of this, the technique of this invention is applicable.

  In the above-described embodiment, the seal structure provided in the bearing unit for the drive wheel is assumed, but the technology of the present invention can be applied to the seal structure for the driven wheel. Furthermore, the present invention is not limited to the seal structure for driving wheels and driven wheels, and can also be applied to seal structures provided in other bearings than the above-described bearing units.

(a) is a sectional view showing a configuration example of a bearing unit for driving wheels, (b) is a sectional view showing a configuration example of a seal structure provided in the bearing unit of FIG. Sectional drawing which shows the structural example of the sealing structure in which the countermeasure against sealing was given, (d) is sectional drawing which shows the structure of the sealing structure which concerns on one embodiment of this invention.

Explanation of symbols

20 Slinger 20a Slinger base 20b Slinger wall J Thermosetting resin

Claims (2)

A seal structure interposed between the bearing rings and sealing the inside of the bearing from the outside of the bearing,
A slinger fitted to one of the races, and a seal body fitted to the other race and slidably contacting the slinger,
The slinger includes a cylindrical slinger base formed with a side peripheral surface that can be fitted to a fitting surface of one of the race rings, and an annular slinger wall portion that is folded back from the slinger base toward the other race ring. Has
A sealing structure characterized in that at least a side peripheral surface of a slinger base is covered with a thermosetting resin among all the surfaces of the slinger. A method for producing the seal structure according to claim 1,
Immersing at least the side peripheral surface of the slinger base in a thermosetting resin stored in the tank;
After lifting the slinger from the tank, the surging thermosetting resin is scattered and temporarily dried by vibrating the slinger, and a resin layer having a predetermined thickness is formed on the side peripheral surface of the slinger base, and
And a step of heat-treating the slinger on which the resin layer is formed at a predetermined temperature.

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