Sealing device

Abstract

To provide a sealing device capable of easily inner-packaging a conductive material to be used for operating the sealing device as a conductive sealing material without complicating the sealing device, and actualizing reliable operation of the conductive material.SOLUTION: A sealing device 10A includes: a core material part 12 to be conductively connected to a fixing member; a seal lip part 13 in contact or contiguity with a rotary member; and a flexible conductive material 14. The core material part 12 includes an overlapping part 12b formed of a metal core plate 12a folded into two layers. The conductive material 14 is: configured with one radial end being held and fixed between the two layers of the overlapping part 12b and with the other radial end being contactable with the rotary member; and arranged in parallel to the seal lip part 13 along an axis L direction of a bearing 1A.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a sealing device mounted between a fixed member and a rotating member in a bearing device.

Background Art

[0002] Conventionally, there has been a problem that when an electric current flows through a bearing device, electric corrosion occurs on the surface of the rolling elements between the fixed member and the rotating member, leading to early failure of the bearing. In particular, since electric vehicles are equipped with many electrical components, there is a risk that a large amount of current will flow into the bearing device.

[0003] In order to solve this problem, as a constituent material of a sealing device mounted to seal the sealed space between the fixed member and the rotating member, a conductive brush material is added to guide the current flowing toward the rolling elements to the sealing device side (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the sealing device of Patent Document 1 is provided not only with a brush material but also with a spring for slidably contacting the brush material with the inner ring and a conducting wire for electrically connecting the brush material to the core metal in order to properly operate the brush material. That is, for the installation of the brush material, a large space for arranging the spring and the conducting wire is required in the sealing device, which may increase the cost and weight. In addition, there is a risk that the sealing device becomes complicated due to the arrangement of the brush material.

[0006] The present invention has been proposed in consideration of such circumstances, and its object is to provide a sealing device that can easily incorporate a conductive material used to make the sealing device act as a conductive sealing material without complicating the sealing device, and can reliably make the conductive material function.

Means for Solving the Problems

[0007] In order to achieve the above object, the sealing device of the present invention is a sealing device mounted between a fixed member and a rotating member in a bearing device in which a fixed member is arranged on one of the outer side and the inner side in the radial direction and a rotating member is arranged on the other side. The sealing device includes a core member portion conductively connected to the fixed member, a seal lip portion in contact with or close to the rotating member, and a flexible conductive material. The core member portion includes a polymerized portion formed by bending a metal core into two layers. One end of the conductive material in the radial direction is sandwiched and fixed between the two layers of the polymerized portion, and the other end in the radial direction is made capable of contacting the rotating member, and is arranged so as to be aligned with the seal lip portion along the axial direction of the bearing device.

Effects of the Invention

[0008] Since the sealing device of the present invention has the above configuration, a conductive material used to make the sealing device act as a conductive sealing material can be easily incorporated without complicating the sealing device, and the conductive material can be reliably made to function.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0011] First, based on FIG. 1, the schematic configuration of the bearing devices 1A and 1B to which the sealing devices 10A to 10H according to the following embodiments are attached will be described. Note that the drawings (see FIGS. 2 to 7) related to various embodiments described below illustrate the sealing devices 10A to 10H in the X portion in FIG. 1.

[0012] The bearing devices 1A and 1B each have an outer ring member 2A, 2B and an inner ring member 3A, 3B that rotate coaxially relative to each other around the axis L of the shaft 5. For example, the outer ring members 2A, 2B are fitted into a housing (not shown), etc., the shaft 5 is inserted through the inner ring members 3A, 3B, and the inner ring members 3A, 3B rotate together with the shaft 5, thereby establishing a relative rotation relationship between the outer ring members 2A, 2B and the inner ring members 3A, 3B. The outer ring members 2A, 2B may be the rotating side and the inner ring members 3A, 3B may be the fixed side.

[0013] Sealing devices 10A to 10H are mounted so as to seal the sealed space 6 between the outer ring members 2A, 2B and the inner ring members 3A, 3B in the bearing devices 1A, 1B from both end portions in the axial direction of the axis L, and a sealed space is formed. In the sealed space 6, a single row of rolling elements 7 (balls in the illustrated example) are held between the outer ring members 2A, 2B and the inner ring members 3A, 3B while being held by a retainer (not shown).

[0014] One of the outer ring members 2A, 2B and the inner ring members 3A, 3B in the bearing devices 1A, 1B is a fixed member, and the other is a rotating member. In short, the sealing devices 10A to 10H are mounted between a fixed member arranged on one of the outer diameter side and the inner diameter side in the radial direction and a rotating member arranged on the other.

[0015] Note that FIG. 1 commonly shows two types of bearing devices 1A, 1A', 1B, 1B', namely, the bearing devices 1A, 1A' in which the outer ring member 2A is a fixed member and the inner ring member 3A is a rotating member, and the bearing devices 1B, 1B' in which the outer ring member 2B is a rotating member and the inner ring member 3B is a fixed member.

[0016] These outer ring members 2A, 2B and inner ring members 3A, 3B are made of a conductive metal material.

[0017] The bearing devices 1A and 1A' to which the four sealing devices 10A to 10D shown in FIGS. 2 to 4 according to the first embodiment are to be attached have an outer ring member 2A as a fixed member and an inner ring member 3A as a rotating member. The bearing devices 1B and 1B' to which the four sealing devices 10E to 10H shown in FIGS. 5 to 7 according to the second embodiment are to be attached have an outer ring member 2B as a rotating member and an inner ring member 3B as a fixed member.

[0018] As the sealing devices 10A to 10H of the present invention, there are two embodiments: one with the outer ring member 2A as the fixed member and the other with the inner ring member 3B as the fixed member. Hereinafter, four examples of the sealing devices 10A to 10H will be given as examples of each embodiment and described. First, the common basic configuration of these sealing devices 10A to 10H will be described (see FIGS. 2 to 7).

[0019] The sealing devices 10A to 10H include a core member portion 12 that is conductively connected to a fixed member (outer ring member 2A, inner ring member 3B), a seal lip portion 13 that contacts or is close to a rotating member (inner ring member 3A, outer ring member 2B), and a flexible conductive material 14. The core member portion 12 includes a polymerized portion 12b formed by bending a metal core 12a into two layers. The conductive material 14 has one end in the radial direction (peripheral edges 14a, 14b) sandwiched and fixed between the two layers of the polymerized portion 12b, and the other end in the radial direction (peripheral edges 14b, 14a) is capable of contacting the rotating member (inner ring member 3A, outer ring member 2B), and is arranged so as to be aligned with the seal lip portion 13 along the axial direction L of the shaft of the bearing devices 1A and 1B.

[0020] The core member portion 12 has a conductive core 12a as a base material, and has the core 12a and an elastic material 11 fixed to at least one surface of the core 12a. The polymerized portion 12b is formed by a part of the core 12a. The core member portion 12 also includes a protrusion 11a made of the elastic material 11 that is fitted into the concave grooves 2A3 and 3B3 formed on the surface of the fixed member (outer ring member 2A, inner ring member 3B) on the side of the sealed space 6.

[0021] The seal lip portion 13 is formed of an elastic material 11. In any of the sealing devices 10A to 10H, the seal lip portion 13 has one lip piece 13a at the tip, but it may have a plurality of lip pieces 13a. The seal lip portion 13 does not have to contact the rotating member (inner ring member 3A, outer ring member 2B), and may be in a proximity relationship. In short, the seal lip portion 13 is a part for suppressing the intrusion of water and other foreign substances into the sealed space 6 by minimizing the gap formed by the relative rotation of the outer ring members 2A, 2B and the inner ring members 3A, 3B as much as possible.

[0022] The elastic material 11 used for the core material portion 12 and the seal lip portion 13 is a rubber material. However, the rubber material may be a conductive rubber material in which a conductive carbon filler or the like is mixed in the rubber material. Examples of the conductive carbon filler include carbon black, carbon fiber, carbon nanofiber, graphite, and the like.

[0023] As the conductive material 14, a brush material or a mesh material made of copper, brass, tungsten, stainless steel, or the like is used. The brush material is an aggregate of metal wire materials, and the mesh material is an aggregate formed by weaving fine metal wires. The conductive material 14 may also be a fiber aggregate made of conductive fibers such as carbon nanofibers.

[0024] In short, the conductive material 14 may be any material that has cavities or spaces inside as a whole, is flexible as a whole, and is easily elastically deformed.

[0025] Next, the sealing devices 10A to 10H according to each embodiment will be individually described with reference to the drawings. First, the four sealing devices 10A to 10D shown in FIGS. 2 to 4 according to the first embodiment will be described. These sealing devices 10A to 10D are mounted on a bearing device 1A having an outer ring member 2A as a fixed member and an inner ring member 3A as a rotating member.

[0026] The sealing device 10A in FIG. 2(a) has a bearing device 1A having the shape shown by the two-dot chain line in the same figure as the mounting target.

[0027] The outer ring member 2A is provided with a fitting recess 2A1 for fitting and fixing the core member portion 12 of the sealing device 10A to the inner diameter portion on the opening 8 side of the sealed space 6. A concave groove 2A3 for elastically fitting the ridge portion 11a of the core member portion 12 is formed at the inner corner of the fitting recess 2A1.

[0028] Also, in the fitting recess 2A1, a fixed-side protruding surface 2A2 along the radial direction from the concave groove 2A3 to the inner diameter surface 2A4 facing the sealed space 6 is formed so as to face outward in the axial direction of the axis L.

[0029] The inner ring member 3A is provided with a notch-shaped recess 3A1 on the outer diameter portion on the opening 8 side of the sealed space 6. The rotation-side protruding surface 3A3 along the radial direction in the notch-shaped recess 3A1 faces outward in the axial direction. The other surface in the notch-shaped recess 3A1 is an inclined surface 3A2, and the inclined surface 3A2 is inclined so that the sealed space 6 expands outward in the axial direction of the axis L.

[0030] As described above, the sealing device 10A includes a core member portion 12, a seal lip portion 13, and a conductive material 14. The elastic material 11 is a material that constitutes a part of the core member portion 12 and the seal lip portion 13.

[0031] The core member portion 12 includes a core metal 12a and includes a laminated portion 12b formed by bending the core metal 12a into two layers. The core metal 12a is arranged such that the first plate portion 12c on the outer side in the axial direction of the axis L extends along the radial direction from the outer diameter side to the inner diameter side, while the second plate portion 12d on the inner side in the axial direction of the axis L is arranged to extend to the middle of the first plate portion 12c in the radial direction from the bending portion 12e with the first plate portion 12c on the outer diameter side. In this way, the overlapping portion of the first plate portion 12c and the second plate portion 12d is the laminated portion 12b.

[0032] At the inner diameter side end of the laminated portion 12b, an opening portion 12f is formed in which the open end of the second plate portion 12d extends in an inclined manner so as to be separated from the first plate portion 12c and opens at an acute angle. Also, the two layers forming the laminated portion 12b are in close contact with each other.

[0033] In the following other embodiments as well, the layer on the outer side in the axial direction L of the core metal 12a will be described as the first plate portion 12c, and the layer arranged on the inner side in the axial direction L via the bent portion 12e will be described as the second plate portion 12d.

[0034] The elastic material 11 is continuously fixed to the outer surface in the axial direction L of the first plate portion 12c and the outer diameter side surface of the bent portion 12e, and a ridge portion 11a protruding further to the outer diameter side is formed on the outer diameter side of the bent portion 12e. This ridge portion 11a is fitted into the concave groove 2A3 of the outer ring member 2A, and the sealing device 10A (core material portion 12) is fitted inside the outer ring member 2A via the ridge portion 11a.

[0035] When the core material portion 12 is fitted to the outer ring member 2A, the inner surface in the axial direction L of the overlapping portion 12b of the core metal 12a, that is, the inner surface of the second plate portion 12d, is in surface contact with the fixed-side protruding surface 2A2. Such surface contact between the core material portion 12 and the fixed-side protruding surface 2A2 of the outer ring member 2A complements the fitting of the sealing device 10A to the outer ring member 2A.

[0036] The elastic material 11 further covers the inner diameter side end surface of the first plate portion 12c and extends further to the inner diameter side from the outer surface of the first plate portion 12c, and a seal lip portion 13 is formed. The seal lip portion 13 includes one lip piece 13a that is inclined outward in the axial direction L on the tip side.

[0037] When the sealing device 10A is properly mounted on the bearing device 1A, the tip of the lip piece 13a contacts the inclined surface 3A2 of the inner ring member 3A. Since the inner ring member 3A is a rotating member, when the inner ring member 3A rotates, the tip of the lip piece 13a of the sealing device 10A fixed to the outer ring member 2A will be in sliding contact with the inclined surface 3A2. Note that the lip piece 13a may be non-contact with the inclined surface 3A2.

[0038] A part of the outer diameter side of the conductive material 14 is sandwiched and fixed between two layers of the overlapping portion 12b and is integrated with the core metal 12a. An opening portion 12f is formed in the overlapping portion 12b, and the conductive material 14 is arranged to extend in an inclined shape along the opening portion 12f.

[0039] The conductive material 14 fixed to the overlapping portion 12b has its peripheral portion 14a on the outer diameter side sandwiched and compressed by caulking between two layers, and its cross-sectional shape is an acute-angled isosceles triangle shape that gradually expands from the peripheral portion 14a on the outer diameter side toward the peripheral portion 14b on the inner diameter side.

[0040] When the sealing device 10A is properly mounted on the bearing device 1A, the end face of the peripheral portion 14b on the inner diameter side of the conductive material 14 contacts near the corner where the rotating-side protruding surface 3A3 and the outer diameter surface 3A4 of the inner ring member 3A meet. That is, as the inner ring member 3A rotates, the conductive material 14 comes into sliding contact with the inner ring member 3A.

[0041] Before being assembled to the core metal 12a, the original shape of the conductive material 14 is an annular shape as shown in the longitudinal sectional view of FIG. 2(b). The conductive material 14 in the present embodiment is made of a brush material in which wire materials are assembled. The peripheral portion 14a on the outer diameter side of the conductive material 14 is formed such that the bases of the wire materials are fixed to each other with a metal material so that the wire materials do not separate from each other.

[0042] The arrows of the two-dot chain lines at the upper and lower positions in FIG. 2(b) indicate the caulking and crimping positions by the overlapping portion 12b of the core metal 12a. In the sealing device 10A shown in FIG. 2(a), the peripheral portion 14a on the outer diameter side of the conductive material 14 is sandwiched and compressed by the overlapping portion 12b of the core metal 12a, while the peripheral portion 14b on the inner diameter side maintains its original thickness. The same applies to the conductive material 14 shown in FIGS. 3(a) and 4(a)(b) described later.

[0043] Also, when manufacturing the sealing device 10A, the wire materials, which are the constituent members of the conductive material 14, may be individually assembled instead of using an integrated one as shown in FIG. 2(b). That is, it is only necessary that the assembled conductive material 14 has an annular brush shape.

[0044] Also, in order to arrange the conductive material 14 as shown in FIG. 2(a), an integrally formed mortar-shaped one as shown in FIG. 2(c) may be integrated with the core metal 12a.

[0045] For example, the conductive material 14 shown in Fig. 2(b) is arranged on the surface of the flat-shaped core metal 12a, the core metal 12a is folded so as to press the peripheral portion 14a on the outer diameter side, and caulking is performed from both sides of the core metal 12a, whereby the core metal 12a and the conductive material 14 can be integrated. Then, the integrated object and the elastic material 11 may be fixed with an adhesive. Note that the fixing of the elastic material 11 and the core metal 12a may be performed by molding.

[0046] Not limited to such a manufacturing method, after forming the overlapping portion 12b so that it can be elastically deformed and opened to form a gap when a force is applied in advance to separate the two layers at the opening portion 12f, the peripheral portion 14a on the outer diameter side of the conductive material 14 is inserted between the two elastically opened layers, and then the conductive material 14 may be sandwiched by caulking the core metal 12a. Note that the fixing of the elastic material 11 and the core metal 12a may be performed by molding before assembling the conductive material 14 to the core metal 12a.

[0047] The fixing of the conductive material 14 to the core metal 12a is not only to compress the peripheral portion 14a on the outer diameter side and sandwich it between the first and second plate portions 12c and 12d, but also to further adhere the conductive material 14 to either one of the two surfaces constituting the opening portion 12f to complement the fixing.

[0048] Also, by adjusting the length of the portion of the conductive material 14 to be sandwiched according to the radial length of the overlapping portion 12b, the sandwiching strength of the conductive material 14 can be adjusted.

[0049] The sealing device 10B shown in Fig. 3(a) has substantially the same shape as the sealing device 10A in Fig. 2(a), but is different in that the opening portion 12f is not formed. That is, the conductive material 14 may be arranged by deforming the one shown in Fig. 2(b) along the inner surface in the axial direction of the first plate portion 12c as shown in Fig. 3(b), and the conductive material 14 may have a shape with a flat upper surface instead of a mortar shape as shown in Fig. 3(b).

[0050] According to the sealing devices 10A and 10B shown in FIGS. 2 and 3, when mounted on the bearing device 1A, the outer ring member 2A and the inner ring member 3A are electrically conductive through the core metal 12a and the conductive material 14. That is, these sealing devices 10A and 10B can serve as conductive sealing materials.

[0051] Further, since the conductive material 14 is sandwiched and caulked by the overlapping portion 12b formed of a part of the core metal 12a, no member for fixing the conductive material 14 inside the sealing devices 10A and 10B is required. The conductive material 14 can be easily installed inside the device, and the sealing devices 10A and 10B can be made compact without being complicated. Also, since it does not require a large-scale device configuration, the weight and cost can be reduced.

[0052] In addition, since the sealing device 10A in FIG. 2 is provided with an opening 12f in the core metal 12a (overlapping portion 12b), it is easy to work when attaching the conductive material 14 to the overlapping portion 12b. On the other hand, since the sealing device 10B in FIG. 3 is configured to attach the upper surface of the conductive material 14 in a flat shape, the sealing device 10B can be made flatter and more compact.

[0053] Also, the opening 12f also plays a role of restricting the swinging (rotational movement centered on the base of the elastic material 11) during the sliding contact operation of the conductive material 14 with respect to the rotating member (inner ring member 3A) according to the degree of opening. That is, it is avoided that the conductive material 14 swings too much and becomes non-contact with the rotating member.

[0054] In addition, since the annular conductive material 14 is provided along the axial direction so as to be aligned with the seal lip 13 portion in the sealing devices 10A and 10B, a part of the function of the seal lip portion 13 can be assigned to the conductive material 14, and the conductive material 14 can be made to act as a second lip piece. For example, it is possible to delay the outflow of the grease arranged in the sealed space 6 to the outside and the entry of foreign matters from the outside. In particular, this is effective for a seal lip portion 13 that is non-contact with the rotating member.

[0055] In addition, since the conductive member 14 is composed of a plurality of wire materials, if the wire materials are made flexible, even when the conductive member 14 is in sliding contact with the rotating member (inner ring member 3A), the possibility of increasing the torque is low. Furthermore, in the case of a device in which the lip piece 13a of the seal lip portion 13 is in a non-contact relationship with the rotating member (inner ring member 3A), it is possible to achieve a reduction in torque, and the seal complement function of the conductive member 14 can avoid a decrease in the sealing function of the sealing devices 10A and 10B.

[0056] Next, the sealing devices 10C and 10D shown in FIGS. 4(a) and 4(b) will be described. The bearing device 1A' to which these sealing devices 10C and 10D are attached has a different shape of the outer diameter portion of the inner ring member 3A compared to the bearing device 1A to which the sealing devices 10A and 10B shown in FIGS. 2 and 3 are attached.

[0057] The inner ring member 3A is provided with an inclined surface 3A2 on the outer diameter portion on the opening 8 side of the sealed space 6 so that the sealed space 6 expands outward in the axial direction of the axis L. Note that this inner ring member 3A does not have the rotating side protruding surface 3A3 shown in FIG. 2, that is, there is no portion protruding radially toward the sealed space 6. In short, on the outer diameter portion, the outer diameter surface 3A4 and the inclined surface 3A2 are continuous without the rotating side protruding surface 3A3 intervening therebetween.

[0058] The sealing devices 10C and 10D shown in FIGS. 4(a) and 4(b) include a superposed portion 12b in which the first plate portion 12c and the second plate portion 12d overlap via a bent portion 12e. The open ends of the first plate portion 12c and the second plate portion 12d are substantially at the same position in the radial direction, and a seal lip portion 13 formed using an elastic material 11 and extending inward in diameter is fixed to the end surface of the open end of the second plate portion 12d.

[0059] At the inner diameter side end of the superposed portion 12b, the open end of the first plate portion 12c extends in an inclined manner so as to be separated from the second plate portion 12d, and an opening portion 12f is formed. Also, the two layers forming the superposed portion 12b are in a close contact state.

[0060] The elastic material 11 is fixed to the surface on the outer diameter side of the opening 12f of the first plate portion 12c and the surface on the outer diameter side of the bent portion 12e. On the outer diameter side of the bent portion 12e, a ridge portion 11a protruding further toward the outer diameter side is formed. The ridge portion 11a fits into the concave groove 2A3, and the sealing devices 10C and 10D (core member portion 12) are fitted into the outer ring member 2A via the ridge portion 11a. The surface contact between the core member portion 12 and the fixed-side protruding surface 2A2 of the outer ring member 2A complements the fitting of the sealing devices 10C and 10D to the outer ring member 2A.

[0061] The seal lip portion 13 has different shapes in FIG. 4(a) and FIG. 4(b). In the seal lip portion 13 of the sealing device 10C in FIG. 4(a), the lip piece 13a protrudes inward in the axial direction L in an inclined shape, and the tip of the lip piece 13a contacts the inclined surface 3A2 of the inner ring member 3A. On the other hand, in the seal lip portion 13 of the sealing device 10D in FIG. 4(b), the lip piece 13a protrudes outward in the axial direction L in an inclined shape, and the tip of the lip piece 13a contacts the outer diameter surface 3A4 of the inner ring member 3A.

[0062] In the sealing devices 10C and 10D shown in FIGS. 4(a) and 4(b), the overall shape of the conductive material 14 is a mortar shape as shown in FIG. 4(c). As the conductive material 14 having this shape, the one shown in FIG. 2(c) can be used by turning it upside down. Also, similar to the sealing device 10A in FIG. 2(a), it is sufficient that the peripheral portion 14a on the outer diameter side of the conductive material 14 is sandwiched between the first and second plate portions 12c and 12d of the overlapping portion 12b.

[0063] Also in the sealing devices 10C and 10D in FIGS. 4(a) and 4(b), the same effects as those of the sealing devices 10A and 10B in FIGS. 2 and 3 are achieved. That is, since the conductive material 14 is sandwiched and caulked in the overlapping portion 12b formed of a part of the core metal 12a, a member for fixing the conductive material 14 in the sealing devices 10C and 10D is not required, the conductive material 14 can be easily installed in the device, and the sealing devices 10C and 10D can be made compact without being complicated. Also, since it does not require a large-scale device configuration, the weight and cost can be suppressed.

[0064] In addition, since these sealing devices 10C and 10D are provided with the opening portion 12f in the core metal 12a (the overlapping portion 12b), the operation when attaching the conductive material 14 to the overlapping portion 12b is easy. Since other effects are the same as those of the sealing device 10A, the description thereof is omitted.

[0065] Also, although the arrangement of the conductive material 14 and the seal lip portion 13 in the axial direction of the axis L is different from that in FIGS. 2 and 3, since it is along the axial direction of the axis L, the conductive material 14 will undertake a part of the function of the seal lip portion 13.

[0066] In the sealing devices 10C and 10D of FIGS. 4(a) and (b), since the first plate portion 12c is shorter than the first plate portion 12c shown in FIGS. 2 and 3, the radial dimension of the core material portion 12 (the core metal 12a) can be made smaller than that in FIGS. 2 and 3. That is, these sealing devices 10C and 10D can be adapted to the bearing device 1A' having a small radial dimension of the sealed space 6.

[0067] Next, the four examples of sealing devices 10E to 10H shown in FIGS. 5 to 7 according to the second embodiment will be described. These sealing devices 10E to 10H are mounted on a bearing device 1B having an outer ring member 2B as a rotating member and an inner ring member 3B as a fixed member.

[0068] The sealing device 10E in FIG. 5(a) is for a bearing device 1B having a shape shown by a two-dot chain line in the same figure as the mounting target.

[0069] It should be noted that the cross-sectional portions shown by two-dot chain lines in FIG. 5 and the like of this bearing device 1B and the bearing device 1B' described later are in a mirror-symmetric shape with those in FIG. 2 and the like. Also, for the sealing devices 10E to 10H, their cross-sectional portions are in a mirror-symmetric relationship between the sealing device 10E and the sealing device 10A. Similarly, there are mirror-symmetric relationships between the sealing device 10F and the sealing device 10B, between the sealing device 10G and the sealing device 10C, and between the sealing device 10H and the sealing device 10D, respectively.

[0070] The inner ring member 3B in Fig. 5(a) is provided with a fitting recess 3B1 for fitting and fixing the core member portion 12 of the sealing device 10E to the outer diameter portion on the opening 8 side of the sealed space 6. A concave groove 3B3 for elastically fitting the ridge portion 11a of the core member portion 12 is formed at the inner corner of the fitting recess 3B1.

[0071] Also, in the fitting recess, a fixed-side protruding surface 3B2 along the radial direction from the concave groove 3B3 to the outer diameter surface facing the sealed space 6 is formed so as to face outward in the axial L direction.

[0072] The outer ring member 2B is provided with a notch-shaped recess 2B1 at the inner diameter portion on the opening side of the sealed space 6. The rotation-side protruding surface 2B3 along the radial direction in the notch-shaped recess 2B1 faces outward in the axial L direction. The other surface in the notch-shaped recess 2B1 is an inclined surface 2B2, and the inclined surface 2B2 is inclined so that the sealed space 6 expands outward in the axial L direction.

[0073] As described above, the sealing device 10E includes a core member portion 12, a seal lip portion 13, and a conductive material 14.

[0074] The core member portion 12 includes a core metal 12a and includes a laminated portion 12b formed by bending the core metal 12a into two layers. The core metal 12a is arranged such that the first plate portion 12c on the outer side in the axial L direction extends along the radial direction from the inner diameter side to the outer diameter side, while the second plate portion 12d on the inner side in the axial L direction is arranged to extend to the middle of the first plate portion 12c in the radial direction from the bent portion 12e with the first plate portion 12c on the inner diameter side. Thus, the overlapping portion of the first plate portion 12c and the second plate portion 12d is the laminated portion 12b.

[0075] At the outer diameter side end of the laminated portion 12b, an opening portion 12f is formed in which the open end of the second plate portion 12d extends in an inclined manner so as to be separated from the first plate portion 12c and opens at an acute angle. Also, the two layers forming the laminated portion 12b are in a closely adhered state.

[0076] The elastic material 11 is continuously fixed to the outer surface of the first plate portion 12c in the axial direction of the shaft L and the inner diameter side surface of the bent portion 12e, and a ridge portion 11a protruding further toward the inner diameter side is formed on the inner diameter side of the bent portion 12e. The ridge portion 11a fits into the concave groove 3B3 of the inner ring member 3B, and the sealing device 10E (core material portion 12) is externally fitted to the inner ring member 3B via the ridge portion 11a.

[0077] When the core material portion 12 is fitted to the inner ring member 3B, the inner surface of the overlapping portion 12b of the core metal 12a in the axial direction of the shaft L, that is, the inner surface of the second plate portion 12d, is in surface contact with the fixed-side protruding surface 3B2. Such surface contact between the core material portion 12 and the fixed-side protruding surface 3B2 of the inner ring member 3B complements the fitting of the sealing device 10E to the inner ring member 3B.

[0078] The elastic material 11 further covers the outer diameter side end surface of the first plate portion 12c and extends further toward the outer diameter side from the outer surface of the first plate portion 12c, and a seal lip portion 13 is formed. The seal lip portion 13 includes one lip piece 13a that is inclined outward in the axial direction of the shaft L on the tip side.

[0079] When the sealing device 10E is properly mounted on the bearing device 1B, the tip of the lip piece 13a contacts the inclined surface 2B2 of the outer ring member 2B. Since the outer ring member 2B is a rotating member, as the outer ring member 2B rotates, the tip of the lip piece 13a of the sealing device 10E fixed to the inner ring member 3B will be in sliding contact with the inclined surface 2B2. Note that the lip piece 13a may be non-contact with the inclined surface 2B2.

[0080] A part of the inner diameter side of the conductive material 14 is sandwiched between two layers of the overlapping portion 12b, fixed, and integrated with the core metal 12a. An opening portion 12f is formed in the overlapping portion 12b, and the conductive material 14 is arranged to extend in an inclined manner along the opening portion 12f.

[0081] The conductive material 14 fixed to the overlapping portion 12b has its inner diameter side peripheral portion 14b sandwiched and compressed by caulking between two layers, and its cross-sectional shape is an acute-angled isosceles triangle shape that gradually expands from the inner diameter side peripheral portion 14b toward the outer diameter side peripheral portion 14a.

[0082] When the sealing device 10E is properly attached to the bearing device 1B, the end face of the peripheral edge portion 14a on the outer diameter side of the conductive material 14 contacts near the corner where the rotating side protruding surface 2B3 and the inner diameter surface 2B4 of the outer ring member 2B meet. That is, as the outer ring member 2B rotates, the conductive material 14 comes into sliding contact with the outer ring member 2B.

[0083] Before being assembled to the core metal 12a, the original shape of the conductive material 14 is an annular shape as shown in the longitudinal sectional view of FIG. 5(b). The conductive material 14 in the present embodiment is composed of a fiber aggregate material made of conductive fibers. The fiber aggregate material is formed so that the conductive fibers do not separate.

[0084] The arrows of the two-dot chain lines at the top and bottom in FIG. 5(b) indicate the clamping caulking positions by the overlapping portion 12b of the core metal 12a. In the sealing device 10E shown in FIG. 5(a), the peripheral edge portion 14b on the inner diameter side of the conductive material 14 is clamped and compressed by the overlapping portion 12b of the core metal 12a, while the peripheral edge portion 14a on the outer diameter side maintains its original thickness. The same applies to the conductive material 14 shown in FIGS. 6(a) and 7(a)(b) described later.

[0085] Also, in order to arrange the conductive material 14 as shown in FIG. 5(a), a conductive material 14 having a mortar shape as shown in FIG. 5(c) may be integrated with the core metal 12a.

[0086] For example, the conductive material 14 of FIG. 5(b) is arranged on the surface of the flat core metal 12a, the core metal 12a is folded so as to press the peripheral edge portion 14b on the inner diameter side, and caulked from both sides of the core metal 12a, whereby the core metal 12a and the conductive material 14 can be integrated. Then, the integrated object and the elastic material 11 may be fixed with an adhesive.

[0087] Note that the sealing device 10E is not limited to such a manufacturing method. Also, the fixing of the conductive material 14 to the core metal 12a may be partially performed using an adhesive.

[0088] The sealing device 10F shown in Fig. 6(a) has substantially the same shape as the sealing device 10E in Fig. 5(a), but is different in that the opening portion 12f is not formed. That is, the conductive material 14 may be arranged by deforming the one shown in Fig. 5(b) as shown in Fig. 6(b) so as to be along the inner surface of the first plate portion 12c in the axial direction of the shaft L. The conductive material 14 may be formed in a shape other than a mortar shape as long as the upper surface is formed in a flat shape as shown in Fig. 6(b).

[0089] Comparing the sealing devices 10E and 10F shown in Figs. 5 and 6 with the sealing devices 10A and 10B in Figs. 2 and 3, the two are in a mirror-symmetrical relationship, and although the materials of the conductive material 14 are different, they are similar in that they have flexibility and flexibility. Therefore, the same effects as those of the sealing devices 10A and 10B can be obtained.

[0090] That is, since the conductive material 14 is sandwiched and caulked by the overlapping portion 12b formed of a part of the core metal 12a, no member for fixing the conductive material 14 in the sealing devices 10E and 10F is required, and the conductive material 14 can be easily installed in the device, and the sealing devices 10E and 10F can be made compact without being complicated. In addition, since it does not become a large-scale device configuration, the weight and cost can be suppressed.

[0091] In addition, since the sealing device 10E in Fig. 5 is provided with the opening portion 12f in the core metal 12a (overlapping portion 12b), the work for attaching the conductive material 14 to the overlapping portion 12b is easy. On the other hand, since the sealing device 10F in Fig. 6 has a configuration in which the upper surface of the conductive material 14 is attached in a flat shape, the sealing device 10B can be made flatter and more compact.

[0092] In addition, since the conductive material 14 is made of a fiber material and is flexible, even when the conductive material 14 is in sliding contact with the rotating member (outer ring member 2B), the possibility of high torque is low. Furthermore, in the case of a device in which the lip piece 13a of the seal lip portion 13 is in a non-contact relationship with the rotating member (outer ring member 2B), low torque can be realized, and the sealing function of the sealing devices 10E and 10F can be prevented from deteriorating due to the seal compensating function of the conductive material 14. Since other effects are the same as those of the sealing devices 10A and 10B, the description is omitted.

[0093] Next, the sealing devices 10G and 10H shown in FIGS. 7(a) and 7(b) will be described. The bearing device 1B´ to which these sealing devices 10G and 10H are attached has a different shape of the inner diameter portion of the outer ring member 2B compared to the bearing device 1B to which the sealing devices 10E and 10F shown in FIGS. 5 and 6 are attached.

[0094] The outer ring member 2B is provided with an inclined surface 2B2 on the inner diameter portion on the opening 8 side of the sealed space 6 so that the sealed space 6 expands outward in the axial direction of the shaft L. Note that this outer ring member 2A does not have the rotating-side protruding surface 2B3 shown in FIG. 5, that is, there is no portion protruding radially toward the sealed space 6. In short, in the inner diameter portion, the inner diameter surface 2B4 and the inclined surface 2B2 are continuous without the rotating-side protruding surface 2B3 intervening therebetween.

[0095] The sealing devices 10G and 10H shown in FIGS. 7(a) and 7(b) include a superposed portion 12b formed by overlapping a first plate portion 12c and a second plate portion 12d via a bent portion 12e. The open ends of the first plate portion 12c and the second plate portion 12d are substantially at the same position in the radial direction, and a seal lip portion 13 formed using an elastic material 11 and extending to the outer diameter side is fixed to the end surface of the open end of the second plate portion 12d.

[0096] At the outer diameter side end of the superposed portion 12b, the open end of the first plate portion 12c extends in an inclined manner so as to be separated from the second plate portion 12d, and an opening portion 12f is formed. Also, the two layers forming the superposed portion 12b are in close contact.

[0097] The elastic material 11 is fixed to the surface on the inner diameter side of the opening portion 12f of the first plate portion 12c and the surface on the inner diameter side of the bent portion 12e, and a ridge portion 11a protruding further toward the inner diameter side is formed on the inner diameter side of the bent portion 12e. This ridge portion 11a fits into the concave groove 3B3, and the sealing devices 10G and 10H (core member portion 12) are fitted into the inner ring member 3B via the ridge portion 11a. The surface contact between the core member portion 12 and the fixed-side protruding surface 3B2 of the inner ring member 3B complements the fitting of the sealing devices 10G and 10H to the inner ring member 3B.

[0098] The shape of the seal lip portion 13 is different between that in Fig. 7(a) and that in Fig. 7(b). In the seal lip portion 13 of the sealing device 10G in Fig. 7(a), the lip piece 13a protrudes in an inclined manner toward the inner side in the axial direction of the shaft L, and the tip of the lip piece 13a contacts the inclined surface 2B2 of the outer ring member 2B. On the other hand, in the seal lip portion 13 of the sealing device 10H in Fig. 7(b), the lip piece 13a protrudes in an inclined manner toward the outer side in the axial direction of the shaft L, and the tip of the lip piece 13a contacts the inner diameter surface 2B4 of the outer ring member 2B.

[0099] In the sealing devices 10G and 10H shown in Figs. 7(a) and 7(b), the overall shape of the conductive material 14 is in the shape of a mortar as shown in Fig. 7(c). As this conductive material 14 of this shape, that shown in Fig. 5(c) can be used by turning it upside down. Also, similar to the sealing device 10E in Fig. 5(a), it is sufficient that the peripheral portion 14b on the inner diameter side of the conductive material 14 is sandwiched between the first and second plate portions 12c and 12d of the overlapping portion 12b.

[0100] Also in the sealing devices 10G and 10H in Figs. 7(a) and 7(b), the same effects as those of the sealing devices 10E and 10F in Figs. 5 and 6 are achieved. That is, since it is a configuration in which the conductive material 14 is sandwiched and caulked in the overlapping portion 12b formed of a part of the core metal 12a, no member for fixing the conductive material 14 in the sealing devices 10G and 10H is required, the conductive material 14 can be easily installed in the device, and the sealing devices 10G and 10H can be made compact without becoming complicated. Also, since it does not become a large-scale device configuration, the weight and cost can be suppressed.

[0101] Further, since these sealing devices 10G and 10H are provided with the opening portion 12f in the core metal 12a (overlapping portion 12b), the work for attaching the conductive material 14 to the overlapping portion 12b is easy. Since the other effects are the same as those of the sealing device 10E, the description is omitted.

[0102] Also, although the arrangement of the conductive material 14 and the seal lip portion 13 in the axial direction of the shaft L is different from those in Figs. 5 and 6, since it is along the axial direction of the shaft L, the conductive material 14 will undertake a part of the function of the seal lip portion 13.

[0103] In the sealing devices 10G and 10H of FIGS. 7(a) and 7(b), since the first plate portion 12c is shorter than the first plate portion 12c shown in FIGS. 5 and 6, the radial dimension of the core material portion 12 (the core metal 12a) can be made smaller than that in FIGS. 5 and 6. That is, these sealing devices 10G and 10H can be adapted to the bearing device 1B' having a small radial dimension of the sealed space 6.

[0104] Since the sealing devices 10A to 10H shown in FIGS. 2 to 4 and FIGS. 5 to 7 described above are all configured such that the conductive material 14 is sandwiched by the polymerized portion 12b, during manufacturing, the sandwiching position and dimension by the polymerized portion 12b of the conductive material 14 and the material of the conductive material 14 can be adjusted while varying them variously to form the sealing devices 10A to 10H.

[0105] In the sealing devices 10A to 10H described above, the conductive material 14 is arranged continuously in a ring shape, but those in a separated state may be arranged discontinuously along the circumferential direction.

[0106] Further, in the above two embodiments (FIGS. 2 to 4 and FIGS. 5 to 7), a brush material and a conductive fiber material are exemplified as the conductive material 14, and they both have a predetermined thickness and are compressible in the thickness direction, but they do not have to be such. For example, a flat mesh material or a punching metal may be used as the conductive material.

[0107] Further, when a conductive rubber material is not used as the elastic material 11 as in the sealing devices 10A to 10H described above, it is desirable that the elastic material 11 and the adhesive for fixing it to the core metal 12a do not prevent the conductive contact between the core metal 12a and the outer ring member 2A. Also, when a conductive rubber material is used as the elastic material 11, in order to utilize the conductivity of the elastic material 11, it is necessary to adjust the amount of the adhesive used between the core metal 12a and the elastic material 11.

[0108] Also, when using a conductive rubber material as the elastic material 11, especially in the case of the sealing devices 10A, 10B, 10E, 10F (see FIGS. 2, 3, 5, and 6), where the elastic material 11 is continuously arranged (without interruption) between the outer ring members 2A, 2B and the inner ring members 3A, 3B, the elastic material 11 can also be used as the main conduction member between the fixed member and the rotating member. In other words, the configuration may be such that the core metal 12a does not contact the fixed member (outer ring member 2A, inner ring member 3B).

[0109] For example, by reducing the protruding degree of the fixed-side protruding surface 2A2 of the outer ring member 2A of the bearing device 1A so that the inner diameter surface 2A4 is arranged at the position indicated by the symbol M in FIG. 2(a), the configuration may be such that the core metal 12a does not contact the fixed member (fixed-side protruding surface 2A2).

[0110] It goes without saying that for these sealing devices 10A, 10B, 10E, 10F as well, the core metal 12a must be made of a metal material having conductivity in order to utilize the conductivity of the conductive material 14.

Explanation of Reference Numerals

[0111] 10A~10H Sealing device 11 Elastic material 11a Ridge portion 12 Core material portion 12a Core metal 12b Overlapping portion 12c First plate portion 12d Second plate portion 12e Bent portion 12f Opening portion 13 Seal lip portion 13a Lip piece 14 Conductive material 14a Peripheral portion on the outer diameter side 14b Peripheral portion on the inner diameter side 1A, 1A´, 1B, 1B´ Bearing device 2A Outer ring member (fixed member) 2A1 Fitting concave portion 2A2 Fixed-side protruding surface 2A3 Groove 2A4 Inner diameter surface 3A Inner ring member (rotating member) 3A1 Notch-shaped recess 3A2 Inclined surface 3A3 Rotating-side protruding surface 3A4 Outer diameter surface 2B Outer ring member (rotating member) 2B1 Notch-shaped recess 2B2 Inclined surface 2B3 Rotating-side protruding surface 2B4 Inner diameter surface 3B Inner ring member (fixed member) 3B1 Fitting recess 3B2 Fixed-side protruding surface 3B3 Concave groove 3B4 Inner diameter surface L Shaft

Claims

1. In a sealing device mounted between a fixed member and a rotating member in a bearing device having a fixed member disposed on one of the outer and inner sides in the radial direction and a rotating member disposed on the other, a core member portion conductively connected to the fixed member, a seal lip portion in contact with or close to the rotating member, and a flexible conductive material, wherein the core member portion includes a polymerized portion formed by bending a metal core into two layers, one end in the radial direction of the conductive material is sandwiched and fixed between the two layers of the polymerized portion, the other end in the radial direction is made capable of contacting the rotating member, and the conductive material is arranged so as to be aligned with the seal lip portion along the axial direction of the bearing device. A sealing device characterized by this.

2. In Claim 1, the sealing device is characterized in that the conductive material is a brush material, a conductive fiber material, or a mesh material.

3. In Claim 1, the sealing device is characterized in that one surface of the polymerized portion is mounted so as to contact the fixed member.

4. In Claim 1, the core member portion comprises an elastic material having conductivity and the core, and the core is fitted to the fixed member via the elastic material. A sealing device characterized by this.

5. In Claim 1, the sealing device is characterized in that the conductive material is an annular material.

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