JP2016151337A - Sealing structure formed by torsional damper and oil seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing structure which is formed by a torsional damper and an oil seal and inhibits a seal lip of the oil seal from being exposed to foreign objects entering from the torsional damper.SOLUTION: A sealing structure 1 formed by a torsional damper and an oil seal includes: a damper pulley 10 serving as the torsional damper; the oil seal 20; and a dust cover 30. The damper pulley 10 includes an inner periphery side projection part 40 which is an annular projection part protruding to an inner side direction in a hub 11. The oil seal 20 includes a side lip 23 extending toward the inner periphery side projection part 40 in an outer side direction. The side lip 23 extends toward the inner periphery side projection part 40. A small clearance 2 having an annular shape is formed between the side lip 23 and the inner periphery side projection part 40. The dust cover 30 covers a space between the hub 11 and a front cover 83 and forms a small clearance 3 between itself and the hub 11.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a sealing structure including a torsional damper and an oil seal, and in particular, a torsional damper for absorbing torsional vibration generated in a rotating shaft of an engine such as a vehicle, and an oil seal for the torsional damper. It is related with the sealing structure formed by.

  For example, in a vehicle engine, a torsional damper is attached to one end of a crankshaft in order to reduce torsional vibration caused by fluctuations in crankshaft rotation. Generally, in a vehicle engine, the torsional damper is used as a damper pulley, and transmits a part of the engine power to an auxiliary machine such as a water pump or an air conditioner compressor via a power transmission belt. In addition, a space between the torsional damper and, for example, a through hole of the front cover through which the crankshaft is inserted is sealed with an oil seal.

  FIG. 7 is a partial cross-sectional view taken along the axis for schematically showing the configuration of a conventional damper pulley and oil seal used in a vehicle engine. As shown in FIG. 7, the conventional damper pulley 100 includes a hub 101, a pulley 102, and a damper elastic body 103 disposed between the hub 101 and the pulley 102. The hub 101 includes an inner boss 101a, an outer rim 101b, and a disc 101c that connects the boss 101a and the rim 101b. The damper pulley 100 is fixed by a bolt 121 with the boss 101 a of the hub 101 fitted into one end of the crankshaft 120.

  The boss 101a of the hub 101 of the damper pulley 100 attached to the crankshaft 120 is inserted into the through hole 123 of the front cover 122 from the outside of the engine, and oil is inserted into the through hole 123 between the boss 101a and the front cover 122. A seal 110 is press-fitted, and a seal lip 111 is slidably contacted with the boss portion 101 a in a liquid-tight manner to seal between the damper pulley 100 and the front cover 122.

  Further, in the conventional damper pulley 100, for the purpose of weight reduction, there is a type in which a plurality of window portions 101d that are through holes penetrating the disc portion 101c of the hub 101 are formed in the circumferential direction (for example, Patent Document 1, Patent Document 1). 2).

Japanese Utility Model Publication No. 05-25049 Japanese Patent No. 5556355

  However, the conventional damper pulley 100 in which the window portion 101d is formed can reduce the weight of the damper pulley 100 in the engine, but foreign matters such as muddy water, sand, and dust can easily enter the engine side through the window portion 101d. . When foreign matter enters the engine side, foreign matter enters between the oil seal 110 and the boss portion 101a, the seal lip 111 bites the foreign matter and is damaged or deteriorated, and the sealing performance of the oil seal 110 is lowered and oil is removed. It may leak.

  For this reason, when using the conventional damper pulley 100 in which the window portion 101d is formed, it is necessary to prevent the seal lip 111 of the oil seal 110 from being exposed to foreign matters entering from the window portion 101d. As described above, when the conventional damper pulley 100 having the window portion 101d is used, the seal lip 111 of the oil seal 110 is exposed to the foreign matter entering from the outer periphery of the damper pulley 100 and the foreign matter entering from the window portion 101d. It was necessary to prevent this.

  The present invention has been made in view of the above-described problems, and an object of the present invention is torsional damper and oil seal capable of suppressing exposure of seal lip of oil seal to foreign matter entering from torsional damper. It is to provide a sealing structure.

  In order to achieve the above object, a sealing structure of a torsional damper and an oil seal according to the present invention is a sealing structure of a torsional damper and an oil seal, and includes a cover member, and the torsional damper includes a hub. An annular mass body centering on an axis surrounding the hub on the outer periphery, and a damper elastic body disposed between the hub and the mass body to elastically connect the hub and the mass body The torsional damper is attached to one end of a rotating shaft with the hub inserted through a through-hole of the mounted portion, and the oil seal is an annular seal lip centered on the axis; An annular side lip centered on the axis, and is attached to the through hole of the attached portion to seal between the hub and the through hole of the attached portion, An annular boss part centered on the axis, an annular rim part centered on the axis located on the outer periphery of the boss part, and a disk centered on the axis connecting the boss part and the rim part A disk-shaped disk part, and an annular inner peripheral ridge part centering on the axis projecting toward the oil seal side, the disk part includes a window part penetrating the disk part, The cover member includes a cylindrical tube portion extending in the axial direction, is attached to the attached portion, and the tube portion is positioned in the vicinity of the window portion of the disk portion of the hub. In the oil seal, the seal lip slidably contacts the boss portion, and the side lip extends toward the inner peripheral ridge portion of the hub, An annular gap is formed between the two.

  In the sealing structure including the torsional damper and the oil seal according to one aspect of the present invention, the end of the cover member on the side of the torsional damper is positioned closer to the inner periphery than the window. And at least one annular groove is formed on the outer peripheral surface.

  In the sealing structure including a torsional damper and an oil seal according to an aspect of the present invention, the disk portion of the hub is an outer peripheral ridge extending in the direction of the attached portion along the inner peripheral surface of the window portion. And the outer peripheral ridge extends obliquely from the disk portion in a direction away from the axis with respect to the direction of the axis, and the cylindrical portion of the cover member includes the outer ridge On the outer peripheral side of the portion, facing the outer peripheral ridge portion, an annular gap is formed between the outer peripheral ridge portion, and at least the inner peripheral surface of the window portion and the cover member Water repellent and oil repellent are applied to the outer peripheral surface of the cylindrical portion.

  In the sealing structure including the torsional damper and the oil seal according to one aspect of the present invention, the side lip of the oil seal has at least one annular groove or protrusion on the outer peripheral surface.

  According to the sealing structure including the torsional damper and the oil seal according to the present invention, it is possible to suppress the seal lip of the oil seal from being exposed to foreign matter entering from the torsional damper.

It is a fragmentary sectional view in the section which meets the axis for showing the schematic structure of the sealing structure by the torsional damper and oil seal concerning a 1st embodiment of the present invention. It is a rear view for showing the schematic structure of the torsional damper in the sealing structure shown in FIG. It is a partial expanded sectional view of the sealing structure by the torsional damper and oil seal shown in FIG. It is a partial expanded sectional view in the section which meets an axis for showing a schematic structure of a sealing structure by a torsional damper and an oil seal concerning a 2nd embodiment of the present invention. It is a fragmentary sectional view for showing the schematic structure of the modification 1 of the oil seal in the sealing structure by the torsional damper and oil seal which concern on 1st, 2nd embodiment of this invention. It is a fragmentary sectional view for showing schematic structure of the modification 2 of the oil seal in the sealing structure by the torsional damper and oil seal which concern on 1st, 2nd embodiment of this invention. It is a fragmentary sectional view in the section which meets an axis for showing roughly composition of a conventional damper pulley and oil seal used in an engine of vehicles.

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

  FIG. 1 is a partial cross-sectional view along the axis for showing a schematic configuration of a sealing structure including a torsional damper and an oil seal according to the first embodiment of the present invention. The sealing structure by the torsional damper and the oil seal according to the first embodiment of the present invention is applied to an automobile engine. Hereinafter, for convenience of explanation, the direction of the arrow a (see FIG. 1) in the direction of the axis x is the outside, and the direction of the arrow b (see FIG. 1) in the direction of the axis x is the inside. More specifically, the outer side is a direction away from the engine, and the inner side is a direction approaching the engine and is the engine side. Further, in a direction perpendicular to the axis x (hereinafter also referred to as “radial direction”), the direction away from the axis x (the direction of arrow c in FIG. 1) is the outer peripheral side, and the direction approaching the axis x (the arrow d in FIG. 1). Direction) is the inner circumference.

  As shown in FIG. 1, the sealing structure 1 by the torsional damper and oil seal which concerns on the 1st Embodiment of this invention is provided with the damper pulley 10 and the oil seal 20 as a torsional damper. The damper pulley 10 is fixed to one end of an engine crankshaft 81 with a bolt 82, and the oil seal 20 seals a through hole 84 of the front cover 83 between the engine front cover 83 and the damper pulley 10. Moreover, the sealing structure 1 by a torsional damper and an oil seal is provided with the dust cover 30 as a cover member attached to the front cover 83 of the engine.

  The damper pulley 10 includes a hub 11, a pulley 12 as a mass body, and a damper elastic body 13 disposed between the hub 11 and the pulley 12. The hub 11 is an annular member centered on the axis line x, and is a substantially disc-shaped disk portion that connects the boss portion 14 on the inner peripheral side, the rim portion 15 on the outer peripheral side, and the boss portion 14 and the rim portion 15. 16. The hub 11 is manufactured from, for example, a metal material by casting or the like.

  In the hub 11, the boss portion 14 is an annular portion centering on the axis line x in which the through hole 14 a is formed, and the disk portion 16 extends from the outer peripheral surface of the outer portion in the outer peripheral direction. The boss portion 14 includes an outer peripheral surface 14b that is a surface on the outer peripheral side of the cylindrical inner portion, and the outer peripheral surface 14b is a smooth surface, which becomes a seal surface of the oil seal 20 as will be described later. Yes. The rim portion 15 is an annular, more specifically cylindrical portion with the axis line x as the center, and is a portion located concentrically with respect to the boss portion 14 and on the outer peripheral side of the boss portion 14. A disk portion 16 extends in the inner peripheral direction from an inner peripheral surface 15a which is a surface on the inner peripheral side of the rim portion 15. A damper elastic body 13 is pressure-bonded to the outer peripheral surface 15 b that is the outer peripheral surface of the rim portion 15.

  The disk portion 16 extends between the boss portion 14 and the rim portion 15 and connects the boss portion 14 and the rim portion 15. The disc part 16 may extend in a direction perpendicular to the axis x, or may extend in a direction inclined with respect to the axis x. Further, the disk portion 16 may have a shape in which a cross section along the axis line x (hereinafter also simply referred to as “cross section”) is curved or a shape that extends straight. As shown in FIGS. 1 and 2, the disk portion 16 is formed with at least one window portion 16a which is a through hole penetrating the disk portion 16 between the inner side and the outer side. In FIG. 2, four window portions 16a are formed concentrically with respect to the axis line x at equal angular intervals in the circumferential direction (see FIG. 2). The window portion 16a reduces the weight of the hub 11, and thus the damper pulley 10.

  The pulley 12 is an annular member centered on the axis x, and has a shape that covers the hub 11 on the outer peripheral side. Specifically, the inner peripheral surface 12a, which is the inner peripheral surface of the pulley 12, has a shape corresponding to the outer peripheral surface 15b of the rim portion 15 of the hub 11, and as shown in FIG. The inner peripheral surface 12a is positioned so as to face the outer peripheral surface 15b of the rim portion 15 with a gap in the radial direction. A plurality of annular v-grooves 12c are formed on the outer peripheral surface 12b, which is the outer peripheral surface of the pulley 12, so that a timing belt (not shown) can be wound.

  The damper elastic body 13 is provided between the pulley 12 and the rim portion 15 of the hub 11. The damper elastic body 13 is a damper rubber, and is formed by crosslinking (vulcanization) molding from a rubber-like elastic material having excellent heat resistance, cold resistance, and fatigue strength. The damper elastic body 13 is press-fitted between the pulley 12 and the rim portion 15 of the hub 11, and is fitted and fixed to the inner peripheral surface 12 a of the pulley 12 and the outer peripheral surface 15 b of the rim portion 15.

  In the damper pulley 10, the pulley 12 and the damper elastic body 13 form a damper portion, and the torsional direction natural frequency of the damper portion is a predetermined frequency region in which the torsion angle of the crankshaft 81 is maximum. The shaft 81 is tuned to match the natural frequency of the torsional direction. That is, the circumferential inertia mass of the pulley 12 and the torsional direction shear spring constant of the damper elastic body 13 are adjusted so that the torsional direction natural frequency of the damper portion matches the torsional direction natural frequency of the crankshaft 81. Has been.

  Further, the damper pulley 10 includes an inner peripheral ridge portion 40 which is an annular ridge portion centering on the axis line x and projecting inward in the hub 11. Details of the inner peripheral ridge 40 will be described later with reference to FIG.

  As described above, the damper pulley 10 is attached to one end of the crankshaft 81. Specifically, as shown in FIG. 1, one end of the crankshaft 81 is inserted into the through hole 14a of the boss portion 14 of the hub 11, and a bolt 82 is screwed into the crankshaft 81 from the outside, so that the damper pulley 10 is cranked. It is fixed to the shaft 81. Further, a key such as a half-moon key that engages the crankshaft 81 and the boss portion 14 is provided between the crankshaft 81 and the boss portion 14, and the damper pulley 10 cannot rotate relative to the crankshaft 81. It has become.

  When attached to the crankshaft 81, the damper pulley 10 is in a state in which the inner portion having the outer peripheral surface 14 b of the boss portion 14 is inserted into the through hole 84 of the front cover 83, and the outer periphery of the boss portion 14 is An annular space is formed between the surface 14 b and the through hole 84 of the front cover 83.

  As shown in FIG. 1, the oil seal 20 includes an annular metal reinforcing ring 21 centered on the axis x and an elastic body portion 22 made of an annular elastic body centered on the axis x. The elastic body portion 22 is integrally attached to the reinforcing ring 21. Examples of the metal material of the reinforcing ring 21 include stainless steel and SPCC (cold rolled steel). Examples of the elastic body of the elastic body portion 22 include various rubber materials. Examples of the various rubber materials include synthetic rubbers such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluorine rubber (FKM).

  The reinforcing ring 21 has a substantially L-shaped cross section, and includes a disk portion 21a and a cylindrical portion 21b. The disc portion 21a is a hollow disc-shaped portion that extends in a direction perpendicular to the axis x, and the cylindrical portion 21b is a cylindrical portion that extends inward in the axis x direction from the outer peripheral end of the disc portion 21a.

  The elastic body portion 22 is attached to the reinforcing ring 21. In the present embodiment, the elastic body portion 22 is formed integrally with the reinforcing ring 21 so as to cover the reinforcing ring 21 from the outside and the outer peripheral side. The elastic body portion 22 includes a lip waist portion 22a, a seal lip 22b, and a dust lip 22c. As shown in FIG. 1, the lip waist portion 22a is a portion located in the vicinity of the inner circumferential end of the disk portion 21a of the reinforcing ring 21, and the seal lip 22b is a portion extending inward from the lip waist portion 22a. It is arranged to face the cylindrical portion 21b of the reinforcing ring 21. The dust lip 22c extends in the direction of the axis x from the lip waist 22a.

  The seal lip 22b has a wedge-shaped annular lip tip 22d having a cross-sectional shape convex toward the inner peripheral side at the inner end. As will be described later, the lip tip portion 22d is formed so as to slidably come into close contact with the outer peripheral surface 14b of the boss portion 14 of the hub 11, and seals between the lip tip portion 22d and the damper pulley 10. Yes. A garter spring 22e that urges the seal lip 22b toward the inner peripheral side in the radial direction is fitted to the outer peripheral portion side of the seal lip 22b.

  The dust lip 22c is a portion extending from the lip waist portion 22a, and extends outward and to the inner peripheral side. The dust lip 22c prevents foreign matter from entering the lip tip 22d in the used state.

  The elastic body portion 22 includes a rear cover 22f and an outer peripheral cover 22g. The rear cover 22f covers the disk portion 21a of the reinforcing ring 21 from the outside, and the outer peripheral cover 22g covers the cylindrical portion 21b of the reinforcing ring 21 from the outer peripheral side.

  The oil seal 20 includes a side lip 23 that extends outwardly toward the inner peripheral ridge 40. Details of the side lip 23 will be described later with reference to FIG.

  The reinforcing ring 21 is manufactured, for example, by pressing or forging, and the elastic body portion 22 is formed by cross-linking (vulcanization) molding using a molding die. At the time of this cross-linking molding, the reinforcing ring 21 is disposed in the mold, the elastic body portion 22 is bonded to the reinforcing ring 21 by cross-linking (vulcanization) bonding, and the elastic body portion 22 is integrated with the reinforcing ring 21. Molded.

  As described above, the oil seal 20 seals a space formed between the through hole 84 of the front cover 83 and the outer peripheral surface 14 b of the boss portion 14 of the damper pulley 10. Specifically, the oil seal 20 is press-fitted and attached to the through hole 84 of the front cover 83, and the outer peripheral cover 22 g of the elastic body portion 22 is compressed to form an inner peripheral surface that is a surface on the inner peripheral side of the through hole 84. 84a is in liquid-tight contact. Thereby, the through hole 84 between the oil seal 20 and the front cover 83 is sealed. Further, the lip tip portion 22d of the seal lip 22b is in liquid-tight contact with the outer peripheral surface 14b of the boss portion 14 of the hub 11, and the space between the oil seal 20 and the damper pulley 10 is sealed.

  The dust cover 30 as a cover member includes a cylindrical tube portion 31 extending in the direction of the axis x, and is attached to the front cover 83. Details of the dust cover 30 will be described later with reference to FIG.

  Next, the inner peripheral ridge 40 of the damper pulley 10, the side lip 23 of the oil seal 20, and the dust cover 30 will be described with reference to FIG. FIG. 3 is a partially enlarged cross-sectional view of the sealing structure 1 including a torsional damper and an oil seal.

  As shown in FIG. 3, the inner peripheral ridge 40 is formed in the disk portion 16 in the damper pulley 10, and has an annular shape centering on an axis line x protruding from the disk portion 16 toward the oil seal 20 side. It is a ridge body part and has a cylindrical shape. The inner peripheral ridge 40 is formed in the disc portion 16 on the inner peripheral side with respect to the window portion 16 a, and the inner peripheral surface 41, which is the inner peripheral surface, faces the outer peripheral surface 14 b of the boss portion 14. ing.

  As shown in FIG. 3, the side lip 23 of the oil seal 20 extends in the outward direction, and more specifically, extends toward the inner peripheral surface 41 of the inner peripheral ridge portion 40. At least a part of the side lip 23 is opposed to the inner peripheral surface 41 of the inner peripheral protrusion 40 in the radial direction, and the outer peripheral surface 24 that is the outer peripheral surface of the side lip 23 and the inner peripheral side A gap 2 is formed between the inner peripheral surface 41 of the protrusion 40 and an annular gap having a predetermined minute width. The outer end 25, which is the outer end of the side lip 23, is not in contact with the inner peripheral surface 41 of the inner peripheral protrusion 40.

  The annular gap 2 formed by the side lip 23 and the inner peripheral ridge 40 forms a labyrinth seal. For this reason, in addition to the gap between the pulley 12 and the front cover 83, even if foreign matter such as muddy water, sand, and dust enters from the outside through the window portion 16 a of the disk portion 16 of the hub 11, The labyrinth seal (gap 2) formed by the circumferential protrusion 40 prevents the foreign matter that has entered from further entering the seal lip 22b. Thereby, it can suppress that the seal lip 22b of the oil seal 20 is exposed to the foreign material which invades from the damper pulley 10 side. For this reason, it can suppress that the lip front-end | tip part 22d bites a foreign material, damages or deteriorates, the sealing performance of the oil seal 20 falls, and oil leaks.

  Specifically, the cylindrical portion 31 of the dust cover 30 has a cylindrical shape with the axis line x as the center, and the dust cover 30 is attached to the inner end 31a, which is an inner end portion of the cylindrical portion 31, at the front. An attachment portion 32 that can be attached to the cover 83 is connected. The attachment portion 32 has a shape that engages and is fixed to a corresponding portion of the front cover 83.

  The dust cover 30 is formed so that the cylindrical portion 31 is positioned in the vicinity of the window portion 16 a of the disk portion 16 of the hub 11 when attached to the front cover 83. Specifically, the cylindrical portion 31 of the dust cover 30 has an outer end 31b, which is an end portion on the outer side (damper pulley 10 side), positioned on the inner peripheral side in the radial direction with respect to the window portion 16a. Opposite to 16, it extends so as to form a gap 3, which is a gap having a minute predetermined width in the direction of the axis x, with respect to the disk portion 16. More specifically, the outer end 31b of the cylindrical portion 31 is connected to the window edge portion 16c, which is a portion close to the inner peripheral surface 16b (see FIG. 2), which is the inner peripheral surface of the window portion 16a. The dust cover 30 is formed and attached to the front cover 83 so as to face each other with the predetermined interval in the axis x direction. The shape of the cylindrical portion 31 extends in parallel with the axis x. The cylinder portion 31 may extend obliquely with respect to the direction of the axis x.

  Further, at least one annular groove 33 that is recessed in the inner peripheral direction is formed on the outer peripheral surface 31 c that is the outer peripheral surface of the cylindrical portion 31 of the dust cover 30. In the present embodiment, two grooves 33 are formed.

  As described above, the cylindrical portion 31 of the dust cover 30 is located between the disk portion 16 of the hub 11 and the front cover 83 on the inner peripheral side of the window portion 16a and on the outer peripheral side of the oil seal 20 in the radial direction. The gap 3 having a very small width is left behind. For this reason, in the dust cover 30, in addition to the gap between the pulley 12 and the front cover 83, foreign matter that has entered from the outside via the window portion 16 a is accumulated on the outer peripheral surface 31 c of the cylindrical portion 31, thereby forming the foreign matter. Can be further prevented from entering the seal lip 22b side. Thereby, it can suppress that the seal lip 22b of the oil seal 20 is exposed to the foreign material which invades from the damper pulley 10 side. For this reason, the dust cover 30 can also prevent the lip tip 22d from being damaged or deteriorated by biting foreign matter, and the oil seal 20 from being deteriorated in sealing performance and leaking oil.

  The minute gap 3 between the outer end 31 b of the cylindrical portion 31 of the dust cover 30 and the hub 11 forms a labyrinth seal. For this reason, even in the gap 3 as the labyrinth seal, it is possible to suppress the foreign matter that has entered from the damper pulley 10 side from further entering the seal lip 22b side, and the seal lip 22b of the oil seal 20 is exposed to the foreign matter. Can be suppressed.

  Further, since the groove 33 is formed on the outer peripheral surface 31 c of the cylindrical portion 31 of the dust cover 30, foreign matter deposited on the outer peripheral surface 31 c is likely to fall down along the groove 33. For this reason, even in the groove 33 formed in the cylindrical portion 31 of the dust cover 30, foreign matter that has entered from the damper pulley 10 side can be further prevented from entering the seal lip 22b side. The exposure of the seal lip 22b can be suppressed.

  As described above, in the sealing structure 1 by the torsional damper and the oil seal according to the first embodiment of the present invention, the seal lip 22b of the oil seal 20 is exposed to foreign matter entering from the damper pulley 10 side. Can be suppressed.

  Next, a sealing structure using a torsional damper and an oil seal according to the second embodiment of the present invention will be described. The sealing structure 50 including the torsional damper and the oil seal according to the second embodiment of the present invention is different from the sealing structure 1 including the torsional damper and the oil seal according to the above-described first embodiment of the present invention. Thus, only the form of the disc part of the hub 11 of the damper pulley 10 and the dust cover is different. Hereinafter, the description of the structure having the same or similar function as the sealing structure 1 including the torsional damper and the oil seal according to the first embodiment of the present invention will be omitted, and the same reference numerals will be given. Only different configurations will be described.

  FIG. 4 is a partially enlarged sectional view in a section along the axis for showing a schematic configuration of a sealing structure 50 including a torsional damper and an oil seal according to the second embodiment of the present invention.

  As shown in FIG. 4, in the sealing structure 50 including the torsional damper and the oil seal, the disk part 51 of the hub 11 of the damper pulley 10 is arranged between the inner side and the outer side, like the disk part 16. At least one window portion 51a which is a through hole penetrating therethrough is formed. In the present embodiment, the four window portions 51a are formed concentrically with the axis line x at equal angular intervals in the circumferential direction. An inner peripheral surface 51b that is a surface on the inner peripheral side of the window 51a is a surface that is inclined with respect to the direction of the axis line x so as to approach the axis line x from the inner side toward the outer side.

  In addition, the disc part 51 includes an outer peripheral ridge part 52 extending in the direction of the front cover 83 (inner side) along the inner peripheral surface 51b of the window part 51a. The outer peripheral protrusion 52 is a protrusion that protrudes from the inner surface of the disk portion 51 toward the front cover 83, and the outer peripheral surface 53 that is the outer peripheral surface extends along the inner peripheral surface 51b of the window 51a. It extends and is flush. That is, the outer peripheral surface 53 of the outer peripheral ridge 52 is a surface that is inclined with respect to the direction of the axis x, similarly to the inner peripheral surface 51b of the window 51a.

  The outer peripheral ridge 52 extends around the entire axis in the circumferential direction in an annular shape, more specifically in a conical cylinder shape around the axis x. Moreover, the outer peripheral side protrusion 52 may be provided corresponding to each window part 51a, respectively. In this case, each of the four outer peripheral ridges 52 extends in the circumferential direction over a length corresponding to the circumferential length of the window 51a. For example, the outer peripheral protrusion 52 may extend in the circumferential direction over the same length as the circumferential length of the window 51a, or may extend in the circumferential direction longer than the circumferential length of the window 51a. Good. However, in the circumferential direction, the inner peripheral surface 51 b of the window portion 51 a is included in the range of the outer peripheral surface 53 of the outer peripheral ridge portion 52.

  Similar to the dust cover 30, the dust cover 60 as a cover member includes a cylindrical tube portion 61 extending in the direction of the axis x, and is attached to the front cover 83. Specifically, the cylindrical portion 31 of the dust cover 60 has a conical cylindrical shape centering on the axis x, and the dust cover 60 is attached to an inner end 61 a that is an inner end portion of the cylindrical portion 61. An attachment portion 62 that can be attached to the front cover 83 is connected. The attachment portion 62 has a shape that is fixed by being engaged with a corresponding portion of the front cover 83.

  When the dust cover 60 is attached to the front cover 83, at least a part of the outer end portion (outer end 61 b) side of the cylindrical portion 61 faces the outer peripheral protrusion 52 from the outer peripheral side. Is formed. Specifically, the cylindrical portion 61 is located on the outer peripheral side of the outer peripheral ridge portion 52, and a small predetermined width is provided between the outer end 61b of the cylindrical portion 61 and the disc portion 51 in the axis x direction. Extending so as to form an interval of. Moreover, the cylinder part 61 is extended in parallel with the outer peripheral side protrusion part 52, and becomes a surface which inclines with respect to the axis line x direction. That is, the cylinder part 61 extends in parallel to the inner peripheral surface 51b of the window part 51a. An inner peripheral surface 61c, which is a surface on the inner peripheral side of the cylindrical portion 61, has a diameter that is the same as that of the outer peripheral surface 53 of the outer peripheral ridge portion 52 in a portion from the outer end 61b of the cylindrical portion 61 to a position spaced a predetermined distance inward. In this portion, an annular gap 4 is formed between the cylindrical portion 61 of the dust cover 60 and the outer peripheral ridge portion 52.

  Further, water repellent and oil repellent p having water repellency and oil repellent action are applied to the inner peripheral surface 51b of the window 51a and the outer peripheral surface 61d which is the outer peripheral surface of the dust cover 60.

  As described above, the annular gap 4 formed by the cylindrical portion 61 of the dust cover 60 and the outer peripheral ridge portion 52 forms a labyrinth seal. For this reason, even in the gap 4 as the labyrinth seal, in addition to the gap between the pulley 12 and the front cover 83, foreign matter that has entered from the outside via the window 51a is further prevented from entering the seal lip 22b side. can do. Thereby, it can suppress that the seal lip 22b of the oil seal 20 is exposed to the foreign material which invades from the damper pulley 10 side. For this reason, the dust cover 60 can also prevent the lip end portion 22d from being damaged or deteriorated by biting foreign matter, and the oil seal 20 from being deteriorated in sealing performance and leaking oil.

  Further, since the cylindrical portion 61 of the dust cover 60 covers the space between the disk portion 51 of the hub 11 and the front cover 83, foreign matter that has entered from the outside through the window portion 51a is placed on the outer peripheral surface 61d of the cylindrical portion 61. It is possible to suppress the foreign matter from further entering the seal lip 22b, and to prevent the seal lip 22b of the oil seal 20 from being exposed to the foreign matter.

  Further, since the water repellent and oil-repellent agent p is applied to the outer peripheral surface 61d of the cylindrical portion 61 of the dust cover 60 and the inner peripheral surface 51b of the window portion 51a of the disk portion 51, it is deposited on the outer peripheral surface 61d. The foreign matter is likely to fall outside or below the damper pulley 10 along the outer peripheral surface 61d and the inner peripheral surface 51b. For this reason, in addition to between the pulley 12 and the front cover 83, it is possible to prevent foreign matter that has entered from the outside through the window portion 51a from further entering the seal lip 22b side. It is possible to prevent the seal lip 22b from being exposed.

  In addition, the sealing structure 50 by the torsional damper and the oil seal is provided with the inner peripheral side ridge 40 formed in the disk part 51, like the sealing structure 1 by the torsional damper and the oil seal. A labyrinth seal (gap 2) is formed between the inner peripheral protrusion 40 and the side lip 23 of the oil seal 20. For this reason, the sealing structure 50 by the torsional damper and the oil seal has the same effect as the sealing structure 1 by the torsional damper and the oil seal.

  As described above, the sealing structure 50 including the torsional damper and the oil seal according to the second embodiment of the present invention is such that the seal lip 22b of the oil seal 20 is exposed to foreign matter entering from the damper pulley 10 side. Can be suppressed.

  In the sealing structure 50 including the torsional damper and the oil seal according to the second embodiment of the present invention, the inner peripheral surface 51b of the window portion 51a is a surface inclined with respect to the axis x. It may be a plane extending parallel to x. Further, the water repellent and oil repellent p may be applied only to the cylindrical portion 61 of the dust cover 60 without being applied to the inner peripheral surface 51b of the window portion 51a.

  Next, a modified example of the oil seal 20 in the sealing structures 1 and 50 including the torsional damper and the oil seal according to the first and second embodiments of the present invention will be described with reference to FIGS.

  FIG. 5 is a partial cross-sectional view for illustrating a schematic configuration of Modification 1 of the oil seal 20 in the sealing structures 1 and 50 including the torsional damper and the oil seal according to the first and second embodiments of the present invention. . The oil seal 70 according to the first modification differs from the oil seal 20 only in the shape of the outer peripheral surface of the side lip 23. Hereinafter, the description of the configuration having the same or similar function as that of the above-described oil seal 20 will be omitted, and the same reference numerals will be given, and only different configurations will be described.

  As shown in FIG. 5, in the oil seal 70 according to the first modification, at least one annular groove 71 that is recessed in the inner peripheral direction is formed on the outer peripheral surface 71 that is the outer peripheral surface of the side lip 23. In the oil seal 70 according to the first modification, two grooves 71 are formed.

  According to the oil seal 70 according to the first modified example, the foreign matter that has entered from the damper pulley 10 side reaches the side lip 23 even when the foreign matter passes through the dust covers 30 and 60 and the gaps 3 and 4. Foreign matter can be discharged downward along the groove 71. Thereby, it can suppress that the seal lip 22b of the oil seal 70 is exposed to the foreign material which invades from the damper pulley 10 side. For this reason, it can suppress that the lip front-end | tip part 22d bites a foreign material, damages or deteriorates, the sealing performance of the oil seal 70 falls, and oil leaks.

  Next, an oil seal 73 according to Modification 2 will be described. FIG. 6 is a partial cross-sectional view for illustrating a schematic configuration of Modification 2 of the oil seal 20 in the sealing structures 1 and 50 including the torsional damper and the oil seal according to the first and second embodiments of the present invention. . Similar to the oil seal 70 according to the first modification, the oil seal 73 according to the second modification differs from the oil seal 20 only in the shape of the outer peripheral surface of the side lip 23. Hereinafter, the description of the configuration having the same or similar function as that of the above-described oil seal 20 will be omitted, and the same reference numerals will be given, and only different configurations will be described.

  As shown in FIG. 6, in the oil seal 73 according to the second modification, at least one annular protrusion 75 convex in the outer peripheral direction is formed on the outer peripheral surface 74 that is the outer peripheral surface of the side lip 23. In the oil seal 73 according to the second modification, two protrusions 75 are formed.

  According to the oil seal 73 according to the second modified example, the foreign matter that has entered from the damper pulley 10 side reaches the side lip 23 even if the foreign matter passes through the dust covers 30 and 60 and the gaps 3 and 4. The foreign matter can be discharged downward along the protrusion 75. Thereby, it can suppress that the seal lip 22b of the oil seal 73 is exposed to the foreign material which penetrate | invades from the damper pulley 10 side. For this reason, it can suppress that the lip front-end | tip part 22d bites a foreign material, damages or deteriorates, the sealing performance of the oil seal 73 falls, and oil leaks.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments of the present invention, and includes all aspects included in the concept and claims of the present invention. In addition, the configurations may be appropriately combined as appropriate so as to achieve at least part of the problems and effects described above. For example, the shape, material, arrangement, size, and the like of each component in the above embodiment can be appropriately changed according to the specific usage mode of the present invention.

  Further, the sealing structures 1 and 50 by the torsional damper and the oil seal according to this embodiment are applied to the engine of the automobile, but the sealing structure by the torsional damper and the oil seal according to the present invention is used. The application target is not limited to this, and the present invention can be applied to all configurations that can use the effects of the present invention, such as rotating shafts of other vehicles, general-purpose machines, and industrial machines.

1, 50 Sealing structure by torsional damper and oil seal 2, 3, 4 Gap 10, 100 Damper pulley 11, 101 Hub 12, 102 Pulley 12a Inner peripheral surface 12b Outer peripheral surface 12c V groove 13, 103 Damper elastic body 14, 101a Boss portion 14a Through hole 14b Outer peripheral surface 15, 101b Rim portion 15a Inner peripheral surface 15b Outer peripheral surface 16, 51, 101c Disc portions 16a, 51a, 101d Window portions 16b, 51b Inner peripheral surface 16c Window edge portions 20, 70, 73 , 110 Oil seal 21 Reinforcement ring 21a Disk part 21b Cylindrical part 22 Elastic body part 22a Lip waist part 22b, 111 Seal lip 22c Dustrip 22d Lip tip part 22e Garter spring 22f Rear cover 22g Outer cover 23 Side lips 24, 71, 74 Outer part Surface 25 Outer edge 30,60 dust Bars 31, 61 Tube portions 31a, 61a Inner ends 31b, 61b Outer ends 31c, 61d Outer peripheral surfaces 61c Inner peripheral surfaces 32, 62 Mounting portions 33 Grooves 40 Inner peripheral ridges 41 Inner peripheral surfaces 52 Outer peripheral ridges 53 Outer peripheral surface 72 Groove 75 Protrusion 81, 120 Crankshaft 82, 121 Bolt 83, 122 Front cover 84, 123 Through hole 84a Inner peripheral surface p Water repellent and oil repellent x axis

Claims (4)

A sealing structure with a torsional damper and an oil seal,
A cover member,
The torsional damper is disposed between a hub, an annular mass body centering on an axis surrounding the hub at an outer periphery, and the hub and the mass body, and elastically supports the hub and the mass body. A torsional damper, and the torsional damper is attached to one end of the rotating shaft, with the hub inserted through the through-hole of the attached portion,
The oil seal includes an annular seal lip centered on the axis and an annular side lip centered on the axis, and is attached to the through-hole of the mounted portion, and the hub and the mounted Sealing between the through hole of the part,
The hub includes an annular boss portion centered on the axis, an annular rim portion centered on the axis located on the outer periphery of the boss portion, and the axis connecting the boss portion and the rim portion. A disc-shaped disc part as a center, and an annular inner peripheral ridge part centering on the axis projecting toward the oil seal,
The disk part includes a window part penetrating the disk part,
The cover member includes a cylindrical tube portion extending in the axial direction, is attached to the attached portion, and the tube portion is positioned in the vicinity of the window portion of the disk portion of the hub. And
In the oil seal, the seal lip slidably contacts the boss portion, and the side lip extends toward the inner peripheral ridge portion of the hub, A sealing structure comprising a torsional damper and an oil seal, characterized by forming an annular gap therebetween.   The cylindrical portion of the cover member is formed such that an end portion on the torsional damper side is positioned on the inner peripheral side with respect to the window portion, and at least one annular groove is formed on the outer peripheral surface. The sealing structure by the torsional damper and oil seal of Claim 1 characterized by the above-mentioned.   The disc portion of the hub includes an outer peripheral ridge portion extending in the direction of the attached portion along the inner peripheral surface of the window portion, and the outer peripheral ridge portion extends from the disc portion to the axis line. The cylinder portion of the cover member is opposed to the outer peripheral ridge portion on the outer peripheral side of the outer peripheral ridge portion, and extends outwardly from the axis direction in a direction away from the outer periphery. An annular gap is formed between the side protrusions, and water and oil repellents are applied to at least the inner peripheral surface of the window portion and the outer peripheral surface of the cylindrical portion of the cover member. 2. A sealing structure comprising a torsional damper and an oil seal according to claim 1.   4. The sealing by the torsional damper and the oil seal according to claim 1, wherein the side lip of the oil seal has at least one annular groove or protrusion on an outer peripheral side surface. 5. Construction.

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