JP2021008918A - Boot band and boot fitting structure - Google Patents

Abstract

To provide a boot band that can further reliably prevent a boot from shifting in an axial direction.SOLUTION: A boot band 9 tightens a boot 8 from a side of the outside diameter thereof by transforming into an annular form to fit the boot 8 to an outside joint member 2 of a constant velocity universal joint 1. In the boot band, a surface 9b to be an inner peripheral surface in the annular form has a recess shape that is recessed in an outer diameter direction at a cross sectional surface crossing in a band longitudinal direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a boot band and a boot mounting structure for mounting boots on an outer joint member or a power transmission shaft.

As a power transmission device used in automobiles and various industrial machines, one in which a constant velocity universal joint is connected to a power transmission shaft such as a drive shaft or a propeller shaft is known.

In this type of power transmission device, in order to prevent dust from entering the inside of the joint and leakage of grease from the inside of the joint, a tubular boot is provided between the power transmission shaft and the constant velocity universal joint. It is installed. Generally, the boot is fastened and fixed to the outer peripheral surface of the outer joint member of the constant velocity universal joint or the outer peripheral surface of the power transmission shaft by using a band-shaped boot band.

The boot band includes a one-touch band disclosed in Patent Document 1, an omega band disclosed in Patent Document 2, and a low profile band disclosed in Patent Document 3. There is something called.

As shown in FIGS. 15A and 15B, the one-touch band narrows the outer diameter of the boot band main body 101 by tilting the lever member 102 along the boot band main body 101. After reducing the diameter of the boot band main body 101, the lever member 102 and the boot band main body 101 are fixed by the stopper 103.

As shown in FIGS. 16A and 16B, the omega band generates a tightening force by crimping the clamp portion 202 provided on the outer peripheral surface of the boot band main body 201 into an omega (Ω) shape. is there.

Further, as shown in FIGS. 17A and 17B, the low profile band is locked by hooking one end 302 of the boot band main body 301 on a hook portion 303 provided on the outer circumference of the boot band main body 301. , It generates a tightening force.

Japanese Unexamined Patent Publication No. 2011-252594 JP-A-2009-127815 Japanese Unexamined Patent Publication No. 2001-219960

By the way, when the constant velocity universal joint takes an operating angle, the boot is deformed accordingly, so that a force for shifting the boot from a predetermined mounting position in the axial direction (joint axial direction or power transmission axial direction) is applied. It works. In particular, when the constant velocity universal joint has a large operating angle, the deformation of the boot also increases, so that the force for shifting the boot in the axial direction increases. If the boots are displaced from the predetermined mounting position due to such a force, the sealing property that the boots should originally exhibit may be deteriorated.

Therefore, an object of the present invention is to provide a boot band and a boot mounting structure that can more reliably prevent the boot from shifting in the axial direction.

In order to solve the above problems, in the present invention, the boot is tightened from the outer diameter side of the boot in an annular shape, and is connected to the outer joint member of the constant velocity universal joint or the inner joint member of the constant velocity universal joint. A boot band for attaching boots to a transmission shaft, characterized in that a surface that is an inner peripheral surface in an annular shape has a concave shape that is recessed in the outer diameter direction in a cross section that intersects in the longitudinal direction of the band.

By tightening the boot from the outer diameter side to the outer joint member or the power transmission shaft by the boot band configured in this way, a restricting force against the axial displacement force of the boot is exerted especially on both end sides in the band width direction. Obtained effectively. This makes it possible to more reliably prevent the boot from shifting in the axial direction.

The inner peripheral surface of the boot band may have a concave shape over the entire band width.

By forming the boot band thicker on both ends than in the center in the band width direction, the rigidity of the boot band increases on both ends in the band width direction, so that the boot band due to the repulsive force when tightening the boots Deformation can be suppressed. As a result, it is possible to effectively prevent the boot from being lifted on both end sides in the band width direction, and the boot band can be more reliably tightened and held.

Further, in the present invention, the boot is tightened from the outer diameter side of the boot by a boot band wound around the outer peripheral surface of the boot in an annular shape, and is connected to the outer joint member of the constant velocity universal joint or the inner joint member of the constant velocity universal joint. A boot mounting structure in which boots are mounted on a power transmission shaft, and the inner peripheral surface of the boot band in an annular shape has a concave shape recessed in the outer diameter direction with a cross section intersecting the longitudinal direction of the band. It is characterized by.

In this way, the inner peripheral surface of the boot band has a concave shape that is recessed in the outer diameter direction at a cross section that intersects the band longitudinal direction, so that the boot is displaced in the axial direction, especially on both ends in the band width direction. Effectively obtains the regulation power of the boot band against the force. This makes it possible to more reliably prevent the boot from shifting in the axial direction.

Further, in the boot mounting structure according to the present invention, the inner peripheral surface of the boot band may have a concave shape over the entire band width.

Further, also in the boot mounting structure according to the present invention, by forming the boot band thicker on both end sides than on the center side in the band width direction, the rigidity of the boot band increases on both end sides in the band width direction. , It becomes possible to suppress the deformation of the boot band due to the repulsive force when the boot is tightened. As a result, the boot can be effectively prevented from being lifted on both ends in the band width direction, and the boot can be more reliably tightened and held with respect to the outer joint member or the power transmission shaft.

The outer and inner peripheral surfaces of the band mounting portion on which the boot band of the boot is mounted, and the outer peripheral surface of the boot mounting portion on which the boot of the outer joint member or the power transmission shaft is mounted are cylindrical surfaces formed with a constant diameter. You may. In this case, when the boot is tightened to the outer joint member or the power transmission shaft by the boot band, the inner peripheral surface of the boot band has a concave shape, so that the tightening force of the boot band is from the central side in the band width direction. Also becomes stronger on both ends. As a result, the restrictive force of the boot band against the axial displacement force of the boot can be effectively obtained, especially on both ends in the band width direction, and the axial displacement of the boot can be prevented more reliably.

Further, the outer peripheral surface of the band mounting portion of the boot is formed in a convex shape bulging in the outer diameter direction in a cross section along the boot axis direction, and the inner peripheral surface of the band mounting portion is formed in a cross section along the boot axis direction. It is formed in a concave shape that is recessed in the outer diameter direction, and the outer peripheral surface of the outer joint member or the boot mounting portion of the power transmission shaft is convex in the outer diameter direction in a cross section along the joint shaft direction or the power transmission shaft direction. It may be formed into a shape. In this case, when the boot is fastened to the outer joint member or the power transmission shaft by the boot band, the boot band and the boot, and the boot and the outer joint member or the power transmission shaft have concave inner peripheral surfaces and convex shapes facing each other. Engages with the outer peripheral surface of. As a result, a restrictive force in the axial direction is generated due to the engagement between the concave inner peripheral surface and the convex outer peripheral surface, and the axial deviation of the boot can be prevented more reliably.

Further, a circumferential groove may be provided on the outer peripheral surface of the boot mounting portion to which the boot of the outer joint member or the power transmission shaft is mounted, and a protrusion that fits into the circumferential groove may be provided on the inner peripheral surface of the boot. In this case, by fitting the protrusion of the boot into the circumferential groove of the outer joint member or the power transmission shaft, the sealing property between the boot and the outer joint member or the power transmission shaft is improved, and the boot shaft is improved. It becomes possible to prevent the deviation of the direction more reliably. In addition, it becomes easier to position the boot with respect to the outer joint member or the power transmission shaft.

According to the present invention, it becomes possible to more reliably prevent the boot from shifting in the axial direction with respect to the outer joint member or the power transmission shaft.

It is sectional drawing of the constant velocity universal joint to which the boot band and the boot mounting structure which concerns on one Embodiment of this invention are applied. It is sectional drawing of the boot mounting structure on the outer joint member side. It is sectional drawing which shows the state before mounting of a boot and a boot band on the outer joint member side. It is sectional drawing which shows the modification of the boot band. It is sectional drawing which shows the other modification of a boot band. It is sectional drawing which shows still another modification of a boot band. It is sectional drawing of the boot mounting structure on the outer joint member side which concerns on other embodiment of this invention. It is sectional drawing which shows the state before mounting of a boot and a boot band on the outer joint member side. It is sectional drawing of the boot mounting structure using another boot band. It is sectional drawing of the boot mounting structure which shows the example which provided the circumferential groove in the boot mounting part of the outer joint member. It is sectional drawing of the boot mounting structure on the shaft side. It is sectional drawing which shows the state before mounting of a boot and a boot band on a shaft side. It is sectional drawing of the boot mounting structure on the shaft side which concerns on other embodiment of this invention. It is sectional drawing which shows the state before mounting of a boot and a boot band on a shaft side. It is a figure which shows an example of a one-touch band. It is a figure which shows an example of an omega band. It is a figure which shows an example of a low profile band.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 3. In each drawing for explaining the present invention, components such as members and components having the same function or shape will be described once by giving the same reference numerals as much as possible. Omit.

FIG. 1 is a cross-sectional view of a constant velocity universal joint to which the boot band and the boot mounting structure according to the embodiment of the present invention are applied.

The constant velocity universal joint 1 shown in FIG. 1 is a so-called Barfield type fixed constant velocity universal joint. The constant velocity universal joint 1 has an outer joint member 2 having a track groove 22 formed on the inner peripheral surface 21 and a plurality of track grooves 32 paired with the track groove 22 of the outer joint member 2 on the outer peripheral surface 31. A plurality of balls 4 as torque transmission members that are interposed between the inner joint member 3, the track groove 22 of the outer joint member 2 and the track groove 32 of the inner joint member 3, and the outer joint member 2. A cage 5 for holding the ball 4 is provided between the inner peripheral surface 21 and the outer peripheral surface 31 of the inner joint member 3.

The outer joint member 2 is formed in a cup shape and opens to one side (right side in FIG. 1) in the joint axial direction. The inner joint member 3 is formed in an annular shape (cylindrical shape). A shaft 6 as a power transmission shaft is inserted into the center hole 33 of the inner joint member 3, and is connected to each other so that power can be transmitted by spline fitting. Further, an annular groove portion 61 is formed at the end portion of the shaft 6, and a retaining ring 7 for preventing the retaining ring is attached to the groove portion 61. As a result, the shaft 6 is prevented from coming off in the axial direction with respect to the inner joint member 3.

A tubular boot 8 is attached between the shaft 6 and the outer joint member 2 to prevent foreign matter from entering from the outside and grease from leaking from the inside. The boot 8 includes a large diameter portion 81, a small diameter portion 82, and a bellows portion 83 connecting the large diameter portion 81 and the small diameter portion 82. The large diameter portion 81 is tightened and fixed to the boot mounting portion 23 on the opening side of the outer joint member 2 by the boot band 9, and the small diameter portion 82 is tightened and fixed to the boot mounting portion 62 in the middle of the shaft 6 by the boot band 10. To.

The boot bands 9 and 10 are band-shaped members, and by forming an annular shape, the large diameter portion 81 or the small diameter portion 82 of the boot 8 is tightened from the outer diameter side thereof, and the boot 8 is tightened to the outer joint member 2 or the shaft 6. It is attached to the boot attachment parts 23 and 62 of. The boot bands 9 and 10 may be a one-touch band as shown in FIGS. 15 (a) and 15 (b), an omega band as shown in FIGS. 16 (a) and 16 (b), or a band shown in FIGS. 17 (a) and 17 (b). It may be a low profile band as shown. The large-diameter portion 81 and the small-diameter portion 82 of the boot 8 are provided with band mounting portions 84 and 85 having grooves formed on the outer peripheral surface over the entire circumference, and the boot bands 9 and 10 are provided with the band mounting portions 84. , 85 fitted in the groove.

FIG. 2 is a cross-sectional view of the boot mounting structure on the outer joint member 2 side in FIG. 1, and FIG. 3 is a cross-sectional view showing a state before mounting the boot 8 and the boot band 9 on the outer joint member 2 side.

As shown in FIGS. 2 and 3, in the present embodiment, the inner peripheral surface 9b of the boot band 9 intersects the boot band 9 in the longitudinal direction (cross section shown in FIG. 2 or 3) and has an outer diameter. It has a concave shape that is recessed in the direction. In addition, the "inner peripheral surface" and "outer diameter direction" of the boot band 9 in this specification mean the inner peripheral surface and the outer diameter direction when the boot band 9 has an annular shape.

Further, as shown in FIG. 2, in a state where the boot band 9 is wound around the boot 8, the direction corresponding to the axial direction of the boot 8 (direction of arrow A in FIG. 2) is defined as the “width direction” of the boot band 9. Alternatively, referred to as the "band width direction", in the present embodiment, the inner peripheral surface 9b of the boot band 9 is recessed so as to have the largest inner diameter at the central portion in the band width direction. The inner peripheral surface 9b of the boot band 9 is formed in a curved surface shape so that the inner diameter gradually decreases from the central portion in the band width direction toward both ends in the band width direction. That is, the inner peripheral surface 9b of the boot band 9 is formed in a concave curved surface shape that is symmetrical in the bandwidth direction with the central portion in the bandwidth direction as the center.

As shown in FIG. 2, the inner peripheral surface 9b of the boot band 9 is formed in a concave curved shape that is symmetrical in the bandwidth direction with the central portion in the bandwidth direction as the center. When the boot 8 is tightened from the outer diameter side by the boot band 9, the inner peripheral surface 9b of the boot band 9 is strongly pressed against the boot 8 on both end sides rather than the center side in the band width direction. That is, while the inner peripheral surface 9b of the boot band 9 is formed in a concave curved shape, the outer peripheral surface and the inner peripheral surface 84a and the inner peripheral surface 84b of the band mounting portion 84 of the boot 8 and the boot mounting portion 23 of the outer joint member 2 Since the outer peripheral surface 23a is a cylindrical surface that is straight in the axial direction (constant diameter), the boot band 9 with respect to the boot 8 when the boot 8 is tightened with respect to the outer joint member 2 by the boot band 9. The surface pressure of is larger on both end sides than on the center side in the band width direction.

As a result, the tightening force of the boot band 9 becomes large, especially on both ends in the width direction of the boot band 9, and the boot 8 can be firmly fixed to the outer joint member 2 and to the outer joint member 2. The displacement of the boot 8 in the axial direction can be prevented more reliably.

Further, when the constant velocity universal joint has a large operating angle, a force for lifting the boot 8 in the outer diameter direction acts on the large diameter portion 81 of the boot 8, especially on the bellows portion 83 side, but the inner circumference of the boot band 9 Since the surface 9b is formed in the concave curved shape as described above, the bellows portion 83 side of the large diameter portion 81 is less likely to be lifted, and the sealing property is improved.

4 to 6 show a modified example of the boot band 9.

In the embodiment shown in FIGS. 2 and 3, the inner peripheral surface 9b of the boot band 9 is formed in a concave curved surface shape over the entire band width, but the portion formed in the concave curved surface shape is the band width. It does not have to be the whole. For example, as in the example shown in FIG. 4, the range from the center portion in the bandwidth direction to the vicinity of both ends of the inner peripheral surface 9b of the boot band 9 is formed in a concave curved surface shape, and both ends and the vicinity thereof are formed in the bandwidth direction. It may be a straight surface (in an annular shape with a constant inner diameter). Further, the portion (inner peripheral surface 9b) formed in the concave curved surface shape does not have to be the entire longitudinal direction of the boot band 9, but the boot band can effectively suppress the displacement in the axial direction of the boot band 8. It is desirable that the inner peripheral surface 9b of the boot band 9 is formed in a concave curved surface shape over at least the entire portion of the boot band 9 wound around the boot 8.

Further, the inner peripheral surface 9b of the boot band 9 may not have a concave curved surface as shown in FIGS. 2 and 3, but may have a concave shape formed by combining straight lines that are inclined to each other as in the example shown in FIG. Good.

Further, the outer peripheral surface 9a of the boot band 9 is not a convex shape (convex curved surface shape) having the same curvature as the inner peripheral surface 9b as shown in FIGS. 2 and 3, but is in the band width direction as in the example shown in FIG. It may be a straight surface (with a constant outer diameter). The "outer peripheral surface" of the boot band 9 as used herein means the outer peripheral surface when the boot band 9 has an annular shape. In the case of the example shown in FIG. 6, since the thickness t of the boot band 9 is thicker on both end sides than on the center side in the band width direction, the rigidity of the boot band 9 is higher on both end sides in the band width direction. Deformation of the boot band 9 due to the repulsive force when the boots are tightened can be suppressed. Therefore, it is possible to effectively prevent the boots 8 from being lifted on both ends in the band width direction, and the boots band 9 can more reliably tighten and hold the boots 8.

Subsequently, other embodiments of the present invention will be described with reference to FIGS. 7 and 8. The parts different from the above-described embodiment will be mainly described, and the other parts are basically the same as those of the above-described embodiment, and thus the description thereof will be omitted.

In the embodiment shown in FIGS. 7 and 8, unlike the above-described embodiment, the outer peripheral surface 84a and the inner peripheral surface 84b of the band mounting portion 84 of the boot 8 and the outer peripheral surface 23a of the boot mounting portion 23 of the outer joint member 2 are formed. , Each is formed in a curved shape following the shape of the inner peripheral surface 9b of the boot band 9. That is, the band mounting portion 84 of the boot 8 has a convex outer peripheral surface 84a bulging in the outer diameter direction and a recess in the outer diameter direction in a cross section along the boot axial direction (cross section shown in FIG. 7 or 8). The boot mounting portion 23 of the outer joint member 2 has a concave inner peripheral surface 84b, and has a convex outer peripheral surface bulging in the outer diameter direction in a cross section along the joint axial direction (cross section shown in FIG. 7). It has 23a.

As described above, in the embodiment shown in FIGS. 7 and 8, in addition to the inner peripheral surface 9b of the boot band 9, the outer peripheral surface 84a and the inner peripheral surface 84b of the band mounting portion 84 of the boot 8 and the boot of the outer joint member 2 Since the outer peripheral surface 23a of the mounting portion 23 is formed in a curved shape, as shown in FIG. 7, when the boot 8 is tightened to the outer joint member 2 by the boot band 9, the boot band 9, the boot 8, and the boot band 8 , The concave inner peripheral surface and the convex outer peripheral surface of the boot 8 and the outer joint member 2 are engaged with each other. As a result, even if an axial force acts on the boot 8, an axial restricting force is generated by the engagement between the concave inner peripheral surface and the convex outer peripheral surface, and the axial deviation of the boot 8 is further increased. It will be possible to prevent it reliably.

The outer peripheral surface 84a and inner peripheral surface 84b of the band mounting portion 84 of the boot 8, and the outer peripheral surface 23a of the boot mounting portion 23 of the outer joint member 2 may be an arc having the same curvature as the inner peripheral surface 9b of the boot band 9, or may be different. It may be an arc of curvature. In particular, when the curvatures of the outer peripheral surfaces 84a and 23a and the inner peripheral surfaces 84b and 9b are the same, the degree of adhesion (degree of engagement) between the concave inner peripheral surface and the convex outer peripheral surface is improved. , The displacement of the boot 8 in the axial direction can be prevented more effectively, and the sealing property of the boot 8 can be improved.

Further, as in the example shown in FIG. 9, the outer peripheral surface 9a of the boot band 9 may be a straight surface as shown in FIG. That is, in this example, the inner peripheral surface 9b of the boot band 9, the outer peripheral surface 84a and the inner peripheral surface 84b of the band mounting portion 84 of the boot 8, and the outer peripheral surface 23a of the boot mounting portion 23 of the outer joint member 2 are curved. The outer peripheral surface 9a of the boot band 9 is formed on a straight surface (cylindrical surface having a uniform outer diameter) in the band width direction. In this case, as described above, the thickness t of the boot band 9 becomes thicker on both end sides than on the center side in the band width direction, and the rigidity on both ends increases, so that the repulsive force at the time of tightening the boots. Deformation of the boot band 9 due to the above can be suppressed, and the boot band 9 can more reliably tighten and hold the boot 8.

Further, as in the example shown in FIG. 10, in the embodiment shown in FIGS. 7 and 8 described above, a circumferential groove 24 is provided on the outer peripheral surface 23a of the boot mounting portion 23 of the outer joint member 2, and the boot facing the groove 24 is provided. The protrusion 86 may be provided on the inner peripheral surface of 8. The circumferential groove 24 and the protrusion 86 may be provided over the entire circumferential direction of the outer joint member 2 or the circumferential direction of the boot 8, or may be partially provided. In this case, as shown in FIG. 10, by fitting the protrusion 86 of the boot 8 into the circumferential groove 24 of the outer joint member 2, the sealing property between the boot 8 and the outer joint member 2 is improved. At the same time, it becomes possible to more reliably prevent the boot 8 from being displaced in the axial direction. Further, the boot 8 can be easily positioned with respect to the outer joint member 2.

The configuration having the circumferential groove 24 and the protrusion 86 is not limited to the configuration in which the outer peripheral surface 9a of the boot band 9 has a convex curved surface shape as shown in FIG. 10, and the boot as shown in FIG. Of course, the outer peripheral surface 9a of the band 9 can also be applied to a straight surface configuration. Further, as shown in FIGS. 2 and 3 described above, the outer peripheral surface 84a and the inner peripheral surface 84b of the band mounting portion 84 of the boot 8 and the outer peripheral surface 23a of the boot mounting portion 23 of the outer joint member 2 are straight ( Even in the configuration of a cylindrical surface (with a constant diameter), the circumferential groove 24 and the protrusion 86 may be provided.

The above embodiment applies the present invention to the boot band and the boot mounting structure on the outer joint member side, but the present invention is not limited to this and can be applied to the boot band and the boot mounting structure on the shaft side. is there.

Hereinafter, embodiments in which the present invention is applied to the boot band and the boot mounting structure on the shaft side will be described with reference to FIGS. 11 to 14.

In the embodiment shown in FIGS. 11 and 12, the inner peripheral surface 10b of the boot band 10 intersects the boot band 10 in the longitudinal direction (cross section shown in FIG. 11 or 12), which is the same as the above-described embodiment. In addition, it has a concave shape that is recessed in the outer diameter direction. On the other hand, the outer peripheral surface and the inner peripheral surface 85b of the band mounting portion 85 and the outer peripheral surface 62a of the boot mounting portion 62 of the shaft 6 on the small diameter portion 82 side of the boot 8 are straight in the axial direction (the diameter is constant). It has a cylindrical surface.

Therefore, in the present embodiment, when the boot 8 is tightened to the shaft 6 from the outer diameter side of the boot band 10, the inner peripheral surface 10b of the boot band 10 has a concave curved surface shape, so that the inner peripheral surface 10b thereof is formed. Both ends in the band width direction are pressed against the boot 8 more strongly than the center side. As a result, the boot 8 can be firmly fixed to the shaft 6 especially on both ends in the width direction of the boot band 10, and the axial deviation of the boot 8 with respect to the shaft 6 can be prevented more reliably. Become. Also in the present embodiment, it is desirable that the portion where the inner peripheral surface 10b of the boot band 10 is formed in a concave curved surface shape is at least the entire portion wound around the boot 8 of the boot band 10.

13 and 14 are views showing another embodiment of the boot mounting structure on the shaft side.

In the embodiment shown in FIGS. 13 and 14, in addition to the inner peripheral surface 10b of the boot band 10, the outer peripheral surface 85a and inner peripheral surface 85b of the band mounting portion 85 of the boot 8 and the outer peripheral surface of the boot mounting portion 62 of the shaft 6 62a is also formed in a curved shape. That is, the band mounting portion 85 of the boot 8 has a convex outer peripheral surface 85a bulging in the outer diameter direction and a recess in the outer diameter direction in a cross section along the boot axial direction (cross section shown in FIG. 13 or 14). The boot mounting portion 62 of the shaft 6 has a concave inner peripheral surface 85b, and has a convex outer peripheral surface 62a bulging in the outer diameter direction in a cross section along the shaft axial direction (cross section shown in FIG. 13). Have.

In this case, as shown in FIG. 13, when the boot 8 is tightened to the shaft 6 by the boot band 10, the boot band 10 and the boot 8, and the boot 8 and the shaft 6 have concave inner peripheral surfaces facing each other. Engage with the convex outer peripheral surface. In this way, by engaging the concave inner peripheral surface and the convex outer peripheral surface, a restrictive force in the axial direction is generated due to these engagements, and the axial deviation of the boot 8 can be prevented more reliably. Will be.

The outer peripheral surface 85a and inner peripheral surface 85b of the band mounting portion 85 of the boot 8 and the outer peripheral surface 62a of the boot mounting portion 62 of the shaft 6 may be arcs having the same curvature as the inner peripheral surface 10b of the boot band 10, or may have different curvatures. It may be an arc. In particular, when the curvatures of the outer peripheral surfaces 85a and 62a and the inner peripheral surfaces 85b and 10b are the same, the degree of adhesion (degree of engagement) between the concave inner peripheral surface and the convex outer peripheral surface is improved. , The displacement of the boot 8 in the axial direction can be suppressed more effectively, and the sealing property of the boot 8 can be improved.

The embodiments in which the present invention is applied to the boot band and the boot mounting structure on the shaft side have been described above based on FIGS. 11 to 14, but in these embodiments, the rigidity of both ends of the boot band 10 in the width direction is increased. In order to improve the boot band 10, the outer peripheral surface of the boot band 10 may be a straight surface in the band width direction as shown in the example shown in FIG. Further, it is also possible to use a boot band having a cross-sectional shape shown in FIGS. 4 and 5 for the boot mounting structure on the shaft side.

Further, in the boot mounting structure on the shaft side, a circumferential groove 24 or a protrusion 86 as shown in FIG. 10 may be provided. That is, by providing a circumferential groove on the outer peripheral surface 62a of the boot mounting portion 62 of the shaft 6 and providing a protrusion that fits with the circumferential groove on the inner peripheral surface of the boot 8, the boot 8 and the shaft 6 are separated from each other. It is possible to improve the sealing property of the boot 8 and more reliably prevent the boot 8 from being displaced in the axial direction. In addition, the boot 8 can be easily positioned with respect to the shaft 6.

Further, the present invention is not limited to the above-described embodiments, and it goes without saying that the present invention can be further implemented in various forms without departing from the gist of the present invention.

In the above-described embodiment, the case where the present invention is applied to either the boot mounting structure on the outer joint member side or the boot mounting structure on the shaft side has been described as an example, but the boot band or boot according to the present invention has been described. The mounting structure may be applied to both the boot mounting structure on the outer joint member side and the shaft side.

The boots used in the present invention may be resin boots, or rubber boots such as thermoplastic elastomer, chloroprene rubber (CR), silicone rubber, and hydrogenated nitrile rubber (HNBR). You may.

Further, the constant velocity universal joint to which the boots are attached is not limited to the Barfield type as shown in FIG. 1, and other fixed constant velocity universal joints such as an undercut free type may be used. Further, the present invention is applicable not only to a fixed constant velocity universal joint but also to a boot mounting structure of a sliding constant velocity universal joint such as a tripod type, a cross groove type, or a double offset type.

It should be noted that the present invention can be expected to have a greater effect by being applied to a fixed constant velocity universal joint capable of having a larger operating angle than a sliding constant velocity universal joint. The fixed constant velocity universal joint provided on the wheel side (outboard side) of an automobile can have a larger operating angle than the sliding constant velocity universal joint provided on the engine side (inboard side). Therefore, the axial force acting on the boot when the operating angle is increased also increases. Therefore, a stronger fixing force is desired in the boot mounting structure of the fixed constant velocity universal joint and the boot band used for the boot mounting structure. Therefore, by applying the present invention to the boot mounting structure of such a fixed constant velocity universal joint and the boot band used therein, it becomes possible to more reliably prevent the displacement of the boot in the axial direction, and the reliability is increased. It is possible to improve the sex.

1 Constant velocity universal joint 2 Outer joint member 3 Inner joint member 6 Shaft (power transmission shaft)
8 Boots 9 Boot band 9a Outer peripheral surface 9b Inner peripheral surface 10 Boot band 10a Outer peripheral surface 10b Inner peripheral surface 23 Boot mounting part 23a Outer peripheral surface 24 Circumferential groove 62 Boot mounting part 62a Outer peripheral surface 81 Large diameter part 82 Small diameter part 83 Bellows 84 Band mounting part 84a Outer peripheral surface 84b Inner peripheral surface 85 Band mounting part 85a Outer peripheral surface 85b Inner peripheral surface 86 Projection

Claims (9)

It is a boot band that tightens the boot from the outer diameter side by forming an annular shape and attaches the boot to the power transmission shaft connected to the outer joint member of the constant velocity universal joint or the inner joint member of the constant velocity universal joint. hand,
A boot band characterized in that the surface that becomes the inner peripheral surface in an annular shape has a concave shape that is recessed in the outer diameter direction in a cross section that intersects in the longitudinal direction of the band. The boot band according to claim 1, wherein the inner peripheral surface has a concave shape over the entire band width. The boot band according to claim 1 or 2, which is formed thicker on both end sides than on the center side in the band width direction. The boot is tightened from the outer diameter side by a boot band wound in an annular shape on the outer peripheral surface of the boot, and is connected to a power transmission shaft connected to an outer joint member of a constant velocity universal joint or an inner joint member of a constant velocity universal joint. It is a boot mounting structure with boots attached.
A boot mounting structure characterized in that the inner peripheral surface of the boot band having an annular shape has a concave shape recessed in the outer diameter direction in a cross section intersecting the band longitudinal direction. The boot mounting structure according to claim 4, wherein the inner peripheral surface of the boot band has a concave shape over the entire band width. The boot mounting structure according to claim 4 or 5, wherein the boot band is formed thicker on both end sides than on the center side in the band width direction. The outer peripheral surface and inner peripheral surface of the band mounting portion to which the boot band of the boot is mounted, and the outer peripheral surface of the outer joint member or the boot mounting portion to which the boot of the power transmission shaft is mounted are formed to have a constant diameter. The boot mounting structure according to any one of claims 4 to 6, which is a cylindrical surface. The outer peripheral surface of the band mounting portion on which the boot band of the boot is mounted is formed in a convex shape bulging in the outer diameter direction in a cross section along the boot axial direction, and the inner peripheral surface of the band mounting portion is formed. It is formed in a concave shape with a cross section along the boot axis direction and recessed in the outer diameter direction.
A claim in which the outer peripheral surface of the outer joint member or the boot mounting portion to which the boot of the power transmission shaft is mounted is formed in a convex shape bulging in the outer diameter direction in a cross section along the joint shaft direction or the power transmission shaft direction. Item 4. The boot mounting structure according to any one of items 4 to 6. A circumferential groove is provided on the outer peripheral surface of the outer joint member or the boot mounting portion to which the boot of the power transmission shaft is mounted.
The boot mounting structure according to any one of claims 4 to 8, wherein a protrusion that fits into the circumferential groove is provided on the inner peripheral surface of the boot.

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