Floating seal device

Abstract

To provide a floating seal device high in housing design freedom.SOLUTION: A floating seal device 1 includes: an inner peripheral surface 2A of a fixation side housing 2; annular elastic rings 41, 51 fitted to an inner peripheral surface 3A of the fixation side housing 3 respectively; and slide components 42, 52 fitted to the housings 2, 3 via the respective elastic rings 41, 51. There are provided core materials 43, 53 fixed to at least one of the elastic rings 41, 51. A part of the core materials 43, 53 extends to an outer diameter side up to a position superimposed in an axial direction on axial direction end surfaces 2a, 3a of the housings 2, 3 located on the outer diameter side of the slide components 42, 52.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a floating seal device for sealing a shaft. [Background technology]

[0002] Conventionally, floating seal devices have been known that seal the space between a fixed structure and a rotating structure when connecting a rotating structure such as a travel motor, roller, idler, axle, etc. to allow the rotating structure to rotate relative to the fixed structure. Such floating seal devices seal the sealed fluid by sliding a pair of seal rings relative to each other, and generally use an elastic ring as a secondary seal, providing a floating function that allows the shaft to tilt.

[0003] For example, in the floating seal device shown in Patent Document 1, a seal ring is attached via an O-ring to the inner diameter side of a rotating track roller, and a seal ring is attached via an O-ring to the inner diameter side of a fixed housing. The track roller and the fixed housing have inner circumferential portions that are recessed in the axial direction from their openings. This inner circumferential portion is composed of a seal surface that decreases in diameter as it moves axially away from the inner circumferential opening, and a wall that extends inward from the opposite side of the seal surface from the inner circumferential opening and continues circumferentially. An O-ring is placed on this inner circumferential portion, and a seal ring is placed inside it.

[0004] For example, when the pressure of soil or sand entering through the gap between the track roller and the fixed housing is high, the pressure acts to separate the O-rings in the axial direction, causing the O-rings to move apart in the axial direction. However, the axial movement is restricted by the walls on the inner periphery of the track roller and the fixed housing, so the sliding surfaces of the seal rings remain in contact with each other. [Prior art documents] [Patent documents]

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when extremely high pressure is applied to the O-ring, such as when the earth and sand pressure is extremely high or the intruded water freezes, the reaction force received by the O-ring from the wall acts greatly, and there is a risk that the sliding surface pressure pressing against the seal ring side becomes excessive.

[0007] The present invention has been made paying attention to such problems, and an object thereof is to provide a floating seal device capable of maintaining a state in which the sliding surfaces of the seal rings are properly in contact with each other.

Means for Solving the Problems

[0008] To solve the above problems, the floating seal device of the present invention comprises: an annular elastic ring attached to the inner peripheral surface of a fixed-side housing and the inner peripheral surface of a rotating-side housing that faces the fixed-side housing and rotates relatively; and a sliding component attached to each of the housings via each of the elastic rings, and is a floating seal device comprising: a core material fixed to at least one of the elastic rings, a part of the core material extends to the outside diameter side up to a position axially overlapping with the axial end surface of the housing located on the outside diameter side of the sliding component. According to this, even when a high pressure acts between the elastic rings on both sides, a part of the core material having rigidity abuts against the axial end surface of the housing, and the movement of the elastic rings in the direction of separating from each other is reliably restricted, so that a state in which the sliding surfaces of the seal rings are properly in contact with each other can be maintained.

[0009] The core material may include an embedded portion embedded in the elastic ring, and an extending portion extending radially outward from the embedded portion. This increases the sense of unity between the elastic ring and the core material.

[0010] The embedded portion may be annular. This allows the force to act on the elastic ring in a well-balanced manner in the circumferential direction.

[0011] The extension may be annular. This provides a high structural strength to the extension portion, and since the extension portion abuts against the end face of the housing in the circumferential direction, the posture of the elastic ring and the sliding part is stable.

[0012] The core member may have a canopy portion extending in the axial direction from the extension portion toward the housing on the opposing side. This allows the eaves portion to prevent soil and sand from entering through the gap between the opposing housings and entering the sliding component side.

[0013] the core material is embedded in the elastic ring attached to the fixed-side housing and the elastic ring attached to the rotating-side housing, The eaves portion of the core material on the fixed side and the eaves portion of the core material on the rotating side may be disposed so as to overlap each other in the radial direction. With this, since the eaves portion on the fixed side and the eaves portion on the rotating side overlap in the radial direction, it is possible to effectively prevent soil and sand from entering the sliding component side.

[0014] The eaves portion of the core material on the rotating side may be disposed radially outward of the eaves portion of the core material on the fixed side. This allows soil and sand that accumulates on the eaves on the rotating side to be discharged to the outside by centrifugal force.

[0015] The overhanging portion of the core material on the inner diameter side may extend at an angle from the extending portion toward the outer diameter direction. According to this, it is possible to effectively suppress the earth and sand that enters the sliding member side through the radial gap between the eaves portions.

[0016] The eaves portion of the core material on the outer diameter side may extend inclined in the inner diameter direction from the extending portion. According to this, it is possible to make it difficult for earth and sand to enter the radial gap between the eaves portions.

[0017] An uneven fitting portion that fits in the radial direction may be provided over the entire circumference in the circumferential direction between the opposing surfaces of the eaves portion on the inner diameter side and the eaves portion on the outer diameter side. According to this, it is possible to effectively suppress the earth and sand that enters the sliding member side through the radial gap between the eaves portions due to the labyrinth effect of the uneven fitting portion.

[0018] A plurality of the eaves portions on the rotating side may be provided along the circumferential direction of the extending portion, and may be inclined outward in diameter from the downstream side of relative rotation to the upstream side of relative rotation in the axial direction view. According to this, it is easy to discharge the earth and sand deposited on the eaves portion on the rotating side to the outside by centrifugal force.

[0019] The elastic ring may include a circumferential wall portion that extends in the circumferential direction and a side wall portion that extends in the inner diameter direction along the back side of the sliding component from the circumferential wall portion. According to this, the sliding component is biased toward the inner diameter side by the circumferential wall portion of the elastic ring and is biased axially toward the opposing sliding component side by the side wall portion of the elastic ring.

[0020] The embedded portion may be embedded within the circumferential wall portion of the elastic ring. According to this, the embedded portion can prevent excessive deformation of each circumferential wall portion of the elastic ring, so that even if earth and sand accumulate in the vicinity of the sliding component, the posture of the sliding component can be stabilized, and since it is not arranged on the side wall portion of the elastic ring, the sliding component has high axial followability.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0022] The embodiments for carrying out the floating seal device according to the present invention will be described below based on examples.

Examples

[0023] The floating seal device according to Example 1 will be described with reference to FIGS. 1 and 2. In addition, the right side of the paper surface of FIG. 1 will be described as one axial end side, and the left side of the paper surface will be described as the other axial end side.

[0024] The floating seal device 1 according to the first embodiment is used to prevent foreign matters such as earth and sand and mud from entering the fixed shaft 9 side from the gap between the fixed housing 2 and the track roller 3 when connecting the track roller 3 as a rotating housing that can rotate relative to the fixed shaft 9 fixed to the side frame supporting the endless track.

[0025] As shown in FIG. 1, the fixed housing 2 is formed in a stepped cylindrical shape that can be externally fitted to the fixed shaft 9, and is fixed in a state of being externally fitted to the fixed shaft 9. The track roller 3 as the rotating housing is formed in a stepped cylindrical shape that can loosely fit the fixed shaft 9, and is arranged in a state of being separated from one end side in the axial direction of the fixed housing 2, and is rotatable relative to the fixed housing 2.

[0026] The floating seal device 1 is mainly composed of a fixed-side element 4 arranged on the inner peripheral portion 2A of the fixed housing 2 and a rotating-side element 5 arranged on the inner peripheral portion 3A of the track roller 3.

[0027] The fixed-side element 4 includes a packing 41 as an elastic ring, a seal ring 42 as a sliding part, and a core material 43 integrally fixed to the packing 41.

[0028] The packing 41 is a cup gasket made of an elastic member such as rubber or synthetic resin. Specifically, as shown in FIG. 2(a), the packing 41 has an annular peripheral wall portion 41a extending in the axial direction and an annular side wall portion 41b extending in the inner diameter direction from the other end side of the peripheral wall portion 41a. The corner formed by the inner peripheral surface 41c of the peripheral wall portion 41a and the one end surface 41d of the side wall portion 41b is a tapered surface 41e whose diameter decreases from one end side in the axial direction to the other end side in the axial direction.

[0029] The seal ring 42 is made of cast iron and is formed in an annular shape that can loosely insert the fixed shaft 9. The end surface of this seal ring 42, that is, the surface on the seal ring 52 side that faces as described later, is a sliding surface 42a that slides with the sliding surface 52a of the seal ring 52.

[0030] As shown in FIGS. 1 and 2, the core member 43 is an annular metal member having a crank-shaped cross section. Specifically, the core member 43 is composed of an annular base portion 43a extending in the axial direction, an annular extension portion 43b protruding from one end of the base portion 43a in the outer diameter direction, and an annular flange portion 43c extending from the outer diameter end of the extension portion 43b to one end side in the axial direction.

[0031] The core member 43 of this embodiment is formed by bending a metal plate. Note that the material of the core member 43 is not limited to metal as long as it is a member having higher rigidity than the packing 41, and it may be formed of resin or the like.

[0032] A part of the inner diameter side of the base portion 43a and the extension portion 43b functions as an embedded portion embedded in the peripheral wall portion 41a of the packing 41. Also, a part of the outer diameter side of the extension portion 43b and the flange portion 43c are not embedded in the packing 41 and are exposed on the outer diameter side.

[0033] The base portion 43a is accommodated and embedded within the radial width W of the peripheral wall portion 41a of the packing 41 (see FIG. 2(a)). In other words, the base portion 43a is not disposed on the side wall portion 41b of the packing 41.

[0034] The seal ring 42 is press-fitted and fixed to the inner peripheral portion 2A of the fixed-side housing 2 via the packing 41. The peripheral wall portion 41a of the packing 41 is disposed on the outer peripheral surface side of the seal ring 42, and the side wall portion 41b is disposed on the back side (i.e., the other end face side) of the seal ring 42. Since the seal ring 42 is press-fitted into the inner diameter side of the packing 41 while elastically deforming the tapered surface 41e of the packing 41, a biasing force acts on the seal ring 42 toward one end side in the inner diameter direction.

[0035] The rotating-side element 5 includes a packing 51 as an elastic ring, a seal ring 52 as a sliding component, and a core member 53 integrally fixed to the packing 51.

[0036] The packing 51 is a cup gasket composed of an elastic member such as rubber or synthetic resin. Specifically, the packing 51 has an annular peripheral wall portion 51a extending in the axial direction and an annular side wall portion 51b extending in the inner diameter direction from one end side of the peripheral wall portion 51a. The packing 51 has a symmetrical shape with the packing 41.

[0037] The seal ring 52 is made of cast iron and is formed in an annular shape that allows the fixed shaft 9 to be loosely inserted. The surface on the other end side of this seal ring 52, that is, the surface on the side facing the seal ring 42, is a sliding surface 52a that slides with the sliding surface 42a of the seal ring 42.

[0038] The core material 53 is an annular metal member having a crank shape in cross-section. Specifically, the core material 53 is composed of an annular base portion 53a extending in the axial direction, an annular extension portion 53b protruding in the outer diameter direction from the other end of the base portion 53a, and an annular eaves portion 53c extending from the outer diameter end of the extension portion 53b to the other end side in the axial direction.

[0039] A part of the inner diameter side of the base portion 53a and the extension portion 53b functions as an embedded portion embedded in the peripheral wall portion 51a of the packing 51. Also, a part of the outer diameter side of the extension portion 53b and the eaves portion 53c are not embedded in the packing 51 and are exposed on the outer diameter side.

[0040] The base portion 53a is embedded within the radial width of the peripheral wall portion 51a in the packing 51. In other words, the base portion 53a is not disposed on the side wall portion 51b of the packing 51.

[0041] The eaves portion 53c of the core material 53 is formed to have a smaller diameter than the eaves portion 43c of the core material 43. That is, in the assembled state of the floating seal device 1, the eaves portion 53c of the rotating-side core material 53 is disposed at a distance from the inner diameter side of the eaves portion 43c of the fixed-side core material 43. In other words, the eaves portion 53c and the eaves portion 43c are disposed so as to overlap in the radial direction.

[0042] The seal ring 52 is press-fitted and fixed to the inner peripheral portion 3A of the track roller 3 via the packing 51. The peripheral wall portion 51a of the packing 51 is disposed on the outer peripheral surface side of the seal ring 52, and the side wall portion 51b is disposed on the back side (i.e., one end face side) of the seal ring 52. Since the seal ring 52 is disposed on the inner diameter side of the packing 51 while elastically deforming the tapered surface of the packing 51, a biasing force acts on the seal ring 52 toward the other end side in the inner diameter direction.

[0043] Next, an example of the assembly procedure of the floating seal device 1 will be described.

[0044] First, referring to FIG. 1, the integrated packing 51 and seal ring 52, that is, the rotating side element 5, are press-fitted into the inner peripheral portion 3A of the track roller 3. At this time, the rotating side element 5 is press-fitted until the other end face 53d of the extending portion 53b abuts against the end face 3a on one axial end side of the track roller 3 located on the outer diameter side of the seal ring 52. By the other end face 53d of the extending portion 53b abutting against the end face 3a of the track roller 3, the axial position of the rotating side element 5 with respect to the track roller 3 is positioned. At this time, the side wall portion 51b of the packing 51 slightly abuts against the end face 3B of the stepped portion provided on the inner peripheral portion 3A of the track roller 3.

[0045] Next, the packing 41 and the seal ring 42 integrated with the inner peripheral portion 2A of the fixed side housing 2 before being fixed to the fixed shaft 9, that is, the fixed side element 4, are press-fitted. At this time, the fixed side element 4 is press-fitted until the one end face 43d of the extending portion 43b abuts against the end face 2a on the other axial end side of the fixed side housing 2 located on the outer diameter side of the seal ring 42. By the one end face 43d of the extending portion 43b abutting against the end face 2a of the fixed side housing 2, the axial position of the fixed side element 4 with respect to the fixed side housing 2 is positioned. At this time, the side wall portion 41b of the packing 41 slightly abuts against the end face 2B provided on the inner peripheral portion 2A of the fixed side housing 2.

[0046] Next, the fixed-side housing 2 with the fixed-side element 4 press-fitted therein is fixed to the fixed shaft 9. At this time, the relative position of the fixed-side housing 2 with respect to the fixed shaft 9 is adjusted so that the sliding surface 42a of the seal ring 42 and the sliding surface 52a of the seal ring 52 abut with a desired surface pressure.

[0047] With the fixed-side housing 2 fixed to the fixed shaft 9, the side wall portions 41b of the packing 41 and the side wall portions 51b of the packing 51 are crushed in the axial direction between the end faces 2B, 3B and the seal rings 42, 52. The seal rings 42 and 52 are urged in directions approaching each other by the elastic restoring forces of the packings 41 and 51, so that the sliding surfaces 42a, 52a are maintained in contact with each other.

[0048] In the floating seal device 1 assembled in this manner, during use, foreign matter such as soil and sand may enter the vicinity of the seal ring 42 and the seal ring 52 from the outside through the axial gap S between the fixed side housing 2 and the track roller 3.

[0049] In such a case, a force acts on the packings 41 and 51 to separate them in the axial direction, but in the floating seal device 1 of this embodiment, one end face 43d of the extension portion 43b abuts against the end face 2a of the fixed housing 2, and the other end face 53d of the extension portion 53b abuts against the end face 3a of the track roller 3, preventing the packings 41 and 51 from separating in the axial direction. This prevents the packings 41 and 51 from being pressed excessively against the end faces 2B and 3B, and maintains a state in which the sliding surfaces 42a and 52a abut against each other with an appropriate surface pressure.

[0050] In addition, as in this embodiment, since there is no need to form wall portions or the like that restrict the movement of the packings 41 and 51 in the insertion direction on the inner peripheral portion 2A of the fixed-side housing 2 or the inner peripheral portion 3A of the track roller 3, the degree of freedom in the design of the fixed-side housing 2 and the track roller 3 can be increased. Needless to say, wall portions or the like that restrict the movement of the packings 41 and 51 in the insertion direction may be additionally provided on the fixed-side housing 2 and the track roller 3.

[0051] Furthermore, in this embodiment, a form is exemplified in which end faces 2B and 3B are provided on the fixed-side housing 2 and the track roller 3 in order to transmit the elastic restoring force of the packings 41 and 51 to the seal rings 42 and 52. However, these configurations may be omitted, and the seal rings may be urged only by the tapered surfaces of the packings.

[0052] In addition, in order to position the extending portions 43b and 53b in contact with the end face 2a of the fixed-side housing 2 and the end face 3a of the track roller 3 that are exposed to the outside, it is possible to confirm from the outside whether the extending portions 43b and 53b are in contact with the end face 2a of the fixed-side housing 2 and the end face 3a of the track roller 3. Compared with the form in which positioning is performed by bringing them into contact with the wall portions provided inside the fixed-side housing 2 and the track roller 3, positioning can be performed more reliably and simply.

[0053] In addition, since the base portions 43a and 53a are embedded in the packings 41 and 51, the integration of the packings 41 and 51 with the core members 43 and 53 is increased, and the movement of the packings 41 and 51 in the insertion direction can be reliably restricted.

[0054] Moreover, the bases 43a, 53a are annular and function to reinforce the peripheral wall portions 41a, 51a of the packings 41, 51, so that force acts on the peripheral wall portions 41a, 51a in a well-balanced manner in the circumferential direction, stabilizing the posture of the seal rings 42, 52. Furthermore, because the inner peripheral surfaces of the bases 43a, 53a and the outer peripheral surfaces of the seal rings 42, 52 are approximately parallel, even if the pressure of invading soil and sand acts in the axial direction, the amount of deformation of the packings 41, 51 between the bases 43a, 53a and the seal rings 42, 52 does not become uneven in the axial direction, and the posture of the seal rings 42, 52 is stabilized.

[0055] In addition, the extension portions 43b, 53b are annular, which increases the structural strength and abuts against the end face 2a of the fixed side housing 2 and the end face 3a of the track roller 3 over the entire circumference, thereby stabilizing the posture of the gaskets 41, 51 and the seal rings 42, 52.

[0056] Furthermore, one end face 43d of the extending portion 43b extends substantially parallel to the end face 2a of the fixed housing 2, and the other end face 53d of the extending portion 53b extends substantially parallel to the end face 3a of the track roller 3. As a result, one end face 43d of the extending portion 43b and the end face 2a of the fixed housing 2 come into face-to-face contact, and the other end face 53d of the extending portion 53b and the end face 3a of the track roller 3 come into face-to-face contact. As a result, foreign matter such as soil and sand is less likely to enter the gap between one end face 43d of extension portion 43b and end face 2a of fixed housing 2, the gap between the other end face 53d of extension portion 53b and end face 3a of track roller 3, and ultimately the gap between inner periphery 2A of fixed housing 2 and peripheral wall portion 41a of packing 41, and the gap between inner periphery 3A of track roller 3 and peripheral wall portion 51a of packing 51, thereby further stabilizing the posture of packings 41, 51 and seal rings 42, 52.

[0057] In addition, the core material 43, 53 is provided with a eaves portion 43c, 53c that covers the gap S, which prevents soil and sand entering through the gap S from entering the inner diameter side of the eaves portion 43c, 53c, i.e., the side of the gaskets 41, 51 and the seal rings 42, 52.

[0058] In addition, the opposing eaves portions 43c, 53c overlap radially, and the gap between the eaves portions 43c, 53c extends axially, so that soil and sand that enters in the inner diameter direction through the gap S is blocked by the eaves portions 43c, 53c, effectively preventing it from entering the seal rings 42, 52 side.

[0059] Furthermore, since the rotating side eave portion 43c is positioned closer to the inner diameter than the fixed side eave portion 53c, soil and sand entering in the inner diameter direction through the gap S is less likely to collide with the rotating eave portion 43c, thereby reducing damage to the core material 43 and the impact on the rotation of the rotating side element 5.

[0060] Furthermore, the bases 43a, 53a are embedded within the radial width W of the peripheral wall portions 41a, 51a of the packings 41, 51, and are not disposed on the side wall portions 41b, 51b of the packings 41, 51. This allows the side wall portions 41b, 51b to be largely elastically deformed in the axial direction, thereby improving the axial compliance of the seal rings 42, 52.

[0061] Furthermore, a portion of the outer diameter side of the extensions 43b, 53b is exposed to the outside of the packings 41, 51. This allows the metal extensions 43b, 53b to directly abut against the end surface 2a of the fixed housing 2 and the end surface 3a of the track roller 3, thereby enabling more accurate positioning than when the extensions 43b, 53b abut via the packings 41, 51. [Example]

[0062] Next, a floating seal device according to a second embodiment will be described with reference to Fig. 3. Note that a description of the same configuration as in the previous embodiment will be omitted.

[0063] 3, in the floating seal device 200 of the second embodiment, the eave portion 253c of the inner diameter side core material 253 extends at an angle from the extension portion 253b toward the outer diameter direction. As a result, sediment that accumulates on the outer diameter side of the eave portion 243c of the outer diameter side core material 243 is easily pushed toward one end and easily discharged to the outside due to centrifugal force. Furthermore, since the radial gap between the eave portion 243c of the outer diameter side core material 243 and the eave portion 253c of the inner diameter side core material 253 is narrowed, sediment that enters through the gap S is less likely to enter the seal rings 242, 252 through the gap between the eave portions 243c, 253c.

[0064] In this second embodiment, the rotating core material 253 is on the inner diameter side and the fixed core material 243 is on the outer diameter side, but as shown in Fig. 4, the rotating core material 253' may be arranged on the outer diameter side and the fixed core material 243' may be arranged on the inner diameter side. In this case as well, sediment that accumulates on the outer diameter side core material 253' is pushed toward one end, and the rotation of the outer diameter side core material 253' allows the sediment to be discharged to the outside by centrifugal force, so sediment is less likely to accumulate on the core material 253'. [Example]

[0065] Next, a floating seal device according to a third embodiment will be described with reference to Fig. 5. Note that a description of the same configuration as in the previous embodiment will be omitted.

[0066] 5, in the floating seal device 300 of the third embodiment, the overhanging portion 353c of the core material 353 on the inner diameter side extends at an angle from the extending portion 353b toward the outer diameter direction. The other end 353e of the overhanging portion 353c rises annularly toward the outer diameter side.

[0067] The overhanging portion 343c of the core material 343 on the outer diameter side extends from the extending portion 343b toward the inner diameter direction at an angle. The overhanging portion 343c is approximately parallel to the overhanging portion 353c. One end portion 343e of the overhanging portion 343c rises in an annular shape toward the inner diameter side.

[0068] According to this, since one end side, i.e., the inlet side, of the gap S2 between the eaves portion 343c and the eaves portion 353c is arranged on the inner diameter side rather than the other end side, i.e., the outlet side, it is difficult for the earth and sand entering from the gap S to enter the gap S2 between the eaves portion 343c and the eaves portion 353c. Further, since the inlet of the gap S2 is narrowed by the extending portion 343b, it is more difficult for the earth and sand to enter the gap S2. Further, even if the earth and sand enters the gap S2, since the other end portion 353e rises on the outlet side of the gap S2, it is difficult to enter the seal ring 342, 352 side.

[0069] In addition, in the third embodiment, a form in which the inner diameter side is the rotating core material 353 and the outer diameter side is the fixed core material 343 is illustrated, but the inner diameter side may be the fixed core material and the outer diameter side may be the rotating core material.

Embodiment

[0070] Next, the floating seal device according to the fourth embodiment will be described with reference to FIG. 6. In addition, the description of the configuration that is the same as that of the above embodiment will be omitted.

[0071] As shown in FIG. 6, in the floating seal device 400 of the fourth embodiment, a concave groove portion 443f that is recessed on the outer diameter side and opens on the inner diameter side is formed in an annular shape in the eaves portion 443c of the core material 443 on the outer diameter side. This concave groove portion 443f is configured by bending a part of the eaves portion 443c to the outer diameter side.

[0072] Further, a convex rib portion 453f that protrudes on the outer diameter side is formed in an annular shape in the eaves portion 453c of the core material 453 on the inner diameter side. This convex rib portion 453f is configured by bending a part of the eaves portion 453c to the outer diameter side.

[0073] In the assembled state of the floating seal device 400, the ribbed portion 453f is loosely fitted into the grooved portion 443f. The grooved portion 443f and the ribbed portion 453f constitute a concavo-convex fitting portion. According to this, since the grooved portion 443f and the ribbed portion 453f that are loosely fitted between the opposing surfaces of the eaves portions 443c and 453c are provided over the circumferential direction, it is difficult for sediment to enter the seal rings 442 and 452 side through the gap between the eaves portions 443c and 453c due to the labyrinth effect of the grooved portion 443f and the ribbed portion 453f.

[0074] In addition, in the present Example 4, the grooved portion 443f and the ribbed portion 453f are exemplified in a form formed by bending a part of the eaves portions 443c and 453c, but it is not limited thereto. For example, a concave portion may be cut and formed in the eaves portion, or a ribbed portion may be formed in the eaves portion by welding or the like.

[0075] Further, in the present Example 4, the form in which the grooved portion 443f is formed in the eaves portion 443c on the outer diameter side and the ribbed portion 453f is formed in the eaves portion 453c on the inner diameter side is exemplified, but a ribbed portion may be provided on the inner diameter side and a concave portion may be provided on the outer diameter side. Also, a plurality of concavo-convex fitting portions composed of a concave portion and a ribbed portion may be provided in the axial direction between the opposing surfaces of the eaves portion.

Example

[0076] [[ID=..]] Next, the floating seal device according to Example 5 will be described with reference to FIGS. 7 and 8. Note that the description of the configuration that is the same as that of the above-described example will be omitted. The form in which the core material 553 rotates in the direction of the black arrow in FIG. 8 (counterclockwise direction in the drawing plane) will be described.

[0077] As shown in FIGS. 7 and 8, in the floating seal device 500 of the present Example 5, the eaves portion 553c of the rotating-side core material 553 is disposed on the outer diameter side with respect to the eaves portion 543c of the fixed-side core material.

[0078] The shielding portions 553c on the rotating side are formed in a plurality along the circumferential direction of the extending portion 553b. These shielding portions 553c are inclined toward the outer diameter side from the downstream side of relative rotation to the upstream side of relative rotation in the axial direction view, and partially overlap with adjacent shielding portions 553c in the radial direction.

[0079] According to this, when the core material 553 rotates, the earth and sand deposited on the shielding portion 553c are blown to the outer diameter side by centrifugal force, so it is difficult for the earth and sand to enter the inner diameter side than the shielding portion 553c. In addition, since adjacent shielding portions 553c partially overlap in the radial direction, it is possible to reduce the entry of earth and sand into the inner diameter side than the shielding portion 553c.

[0080] In addition, in the present Example 5, a form in which a plurality of shielding portions 553c are provided independently is illustrated, but the upstream end portion in the rotation direction of one shielding portion and the downstream end portion in the rotation direction of the shielding portion adjacent to the upstream side in the rotation direction may be connected in the radial direction. Thereby, it is possible to suppress the entry of earth and sand from the gap between adjacent shielding portions.

Example

[0081] Next, the floating seal device according to Example 6 will be described with reference to FIGS. 9 and 10. In addition, the description of the configuration that is the same as that of the above Example 1 will be omitted.

[0082] As shown in FIGS. 9(a) and 9(b), in the floating seal device 600 of the present Example 5, shielding portions are not provided on the core materials 643 and 653. Since the core materials 643 and 653 have substantially the same configuration, the core material 643 will be described below and the description of the core material 653 will be omitted.

[0083] Specifically, the core material 643 includes a base portion 643a, an extending portion 643b, and an annular bent portion 643c extending from the outer diameter end of the extending portion 643b to the other end side in the axial direction.

[0084] The bent portion 643c abuts against the outer peripheral surface 602b of the fixed-side housing 602. The bent portion 643c may be formed in advance, or may be formed by bending the outer diameter end of the extending portion 643b toward the other axial end after the extending portion 643b is brought into abutment against the end surface 602a of the fixed-side housing 602.

[0085] This makes it possible to suitably prevent soil and sand from getting between extending portion 643b and end surface 602a of fixed-side housing 602. Furthermore, it makes it possible to suitably prevent soil and sand from getting between the inner circumferential portion of fixed-side housing 602 and packing 641. By preventing soil and sand from getting into these areas and by fixing packing 641 to fixed-side housing 602 using extending portion 643b extending from packing 641, even if soil and sand get into the vicinity of the sliding surface of the seal ring, packing 641 is prevented from being pushed in, and tilting of the seal ring is suppressed.

[0086] 10(a), the core 643′ may not be provided with the bent portion 643c, and the extending portion 643b′ may be welded to the end surface 602a′ of the fixed housing 602′. In this embodiment, a tapered surface 643e that slopes inward from the other axial end toward the one axial end is formed on the outer diameter end of the extending portion 643b′, thereby making it possible to suitably prevent soil and sand from entering between the extending portion 643b′ and the end surface 602a′ of the fixed housing 602′.

[0087] 10(b), the core 643'' may have an adhesive layer 610 formed of an adhesive between the outer diameter side portion of the extending portion 643b'' and the end surface 602a'' of the fixed housing 602''. This makes it possible to preferably prevent soil and sand from getting between the extending portion 643b'' and the end surface 602a'' of the fixed housing 602''.

[0088] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0089] For example, in the above Examples 1 to 6, the form in which a part of the core material is embedded in the elastic ring was exemplified, but the present invention is not limited thereto, and the entire core material may be embedded in the elastic ring, or the entire core material may be exposed outside the elastic ring, that is, a part of the core material may not be embedded in the elastic ring and may be fixed outside the elastic ring with an adhesive or the like.

[0090] In addition, in the above Examples 1 to 6, the form in which the embedded portion of the core material embedded in the elastic ring forms an annular shape was exemplified. For example, it may be C-shaped when viewed axially, or may be in an arc shape in which a plurality of them are arranged at intervals in the circumferential direction.

[0091] In addition, in the above Examples 1 to 6, the form in which the extending portion of the core material forms an annular shape was exemplified. For example, it may be C-shaped when viewed axially, or a plurality of them may be arranged at intervals in the circumferential direction of the base portion of the core material.

[0092] In addition, in the above Examples 1 to 6, the form in which the core material is provided on the rotating element and the fixed element was exemplified, but the core material may be provided on at least one of the rotating element and the fixed element.

[0093] In addition, in the above Examples 1 to 6, the form in which the eaves portions are respectively provided on the core material of the rotating element and the core material of the fixed element was exemplified, but the eaves portion may be provided on the core material of at least one side.

[0094] In addition, in the above Examples 1 to 6, the form in which the base portion of the core material is accommodated and embedded in the peripheral wall portion of the elastic ring was exemplified, but the present invention is not limited thereto, and it may also be embedded in the side wall portion of the elastic ring. According to this, by restricting the movement of the side wall portion, the axial movement of the sliding component can be restricted.

[0095] In addition, in the above Embodiments 1 to 6, the floating seal device has been described as being used for a side frame and a track roller that constitute an endless track. However, the present invention is not limited to this, and it may be used for a traveling motor, an idler, an axle, etc., and is not limited. For example, a device including a rotating shaft, a rotating-side housing fixed to the rotating shaft, and a fixed-side housing through which the rotating shaft is inserted, and sealing between the rotating-side housing and the fixed-side housing may be used.

[0096] In addition, in the above Embodiments 1 to 6, the fixed-side housing has been described as a fixed-side housing attached to the fixed-side structure. However, the present invention is not limited to this, and it may be a part of the fixed-side structure or the fixed-side structure itself, and is not limited. Similarly, the rotating-side housing has been described as a track roller that is the rotating-side structure itself. However, the present invention is not limited to this, and it may be attached to the rotating-side structure or may constitute a part of the rotating-side structure, and is not limited.

[0097] In addition, in the above Embodiments 1 to 6, the elastic ring has been exemplified as a cup gasket. However, an O-ring having a circular cross-section or an elastic ring having a cross-section other than circular may be used. For example, as shown in FIG. 11, in a generally widely used floating seal device, a core material 743, 753 may be partially embedded and fixed to elastic rings 741, 751 that are O-rings having a circular cross-section.

Explanation of Reference Numerals

[0098] 1 Floating seal device 2 Fixed-side housing 2a End face (axial end face) 3 Track roller (rotating-side housing) 3a End face (axial end face) 4 Fixed-side element 5 Rotating-side element 9 Fixed shaft 41 Packing 41a Peripheral wall portion 41b Side wall portion 42 Seal ring (sliding part) 42a Sliding surface 43 Core material 43a Base (buried part) 43b Extension 43c Eaves 51 Gasket 51a Peripheral wall part 51b Side wall part 52 Seal ring (sliding part) 52a Sliding surface 53 Core material 53a base 53b Extension 53c Eaves

Claims

1. An annular elastic ring respectively attached to the inner peripheral surface of the fixed housing and the inner peripheral surface of the rotating housing that faces the fixed housing and rotates relatively, and a sliding component attached to each of the housings via each of the elastic rings, a floating seal device comprising: comprising a core material fixed to at least one of the elastic rings, A floating seal device in which a part of the core material extends outward in diameter to a position axially overlapping with the axial end face of the housing located on the outer diameter side of the sliding component.

2. The floating seal device according to claim 1, wherein the core material includes an embedded portion embedded in the elastic ring and an extending portion extending in the outer diameter direction from the embedded portion.

3. The floating seal device according to claim 2, wherein the embedded portion forms an annulus.

4. The floating seal device according to claim 3, wherein the extending portion forms an annulus.

5. The floating seal device according to claim 2, wherein the core material has a flange portion extending axially from the extending portion toward the housing on the opposite side.

6. The core material is respectively embedded in the elastic ring attached to the fixed housing and the elastic ring attached to the rotating housing, The floating seal device according to claim 5, wherein the flange portions of the core material on the fixed side and the flange portions of the core material on the rotating side are arranged to overlap in the radial direction.

7. The floating seal device according to claim 6, wherein the flange portion of the core material on the rotating side is arranged on the outer diameter side of the flange portion of the core material on the fixed side.

8. The floating seal device according to claim 6, wherein the flange portion of the core material on the inner diameter side extends obliquely in the outer diameter direction from the extending portion.

9. The floating seal device according to claim 8, wherein the flange portion of the core material on the outer diameter side extends obliquely in the inner diameter direction from the extending portion.

10. The floating seal device according to claim 6, wherein an uneven fitting portion that fits in the radial direction is provided over the entire circumference in the circumferential direction between the opposing surfaces of the flange portion on the inner diameter side and the flange portion on the outer diameter side.

11. The floating seal device according to claim 6, wherein a plurality of flange portions on the rotating side are provided along the circumferential direction of the extending portion and are inclined outward in diameter from the downstream side of relative rotation to the upstream side of relative rotation in an axial view.

12. The floating seal device according to any one of claims 1 to 11, wherein the elastic ring includes a circumferential wall portion extending in the circumferential direction and a side wall portion extending in the inner diameter direction along the back side of the sliding component from the circumferential wall portion.

13. The floating seal device according to claim 12, wherein the embedded portion is accommodated and embedded in the circumferential wall portion of the elastic ring.

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