WO2004113753A1

WO2004113753A1 - Boot ring

Info

Publication number: WO2004113753A1
Application number: PCT/JP2004/008941
Authority: WO
Inventors: Takashi Ogino; Shuji Ando
Original assignee: Nhk Spring Co., Ltd.
Priority date: 2003-06-20
Filing date: 2004-06-18
Publication date: 2004-12-29
Also published as: JP4330938B2; JP2005009641A

Abstract

Seal portions (1a) at both ends of a boot (1) covering a joint device are respectively fitted on fitting portions (4), where seal grooves (4c) are formed along their entire circumferences, of the joint device. After that a boot ring (10) is tightened on a seal portion (1a) to fix the boot (1) on the joint device. Pressing portions (10a) are provided on the entire circumference of an inner periphery of the boot ring, and the pressing portions locally press the seal portion (1a) of the boot (1) against both edge portions (Ps) of a seal groove (4c).

Description

Boots ring

Technical field

The present invention relates to a boot ring of a joint device used in a vehicle such as an automobile. Akita

Background art

In vehicles such as automobiles, constant velocity joints are used as joints for transmitting the driving force of an engine from a drive shaft to a driven shaft. In this constant velocity joint, the joint part of the bearing structure that connects the drive shaft and the driven shaft is covered with a bellows-shaped boot filled with grease, and when the vehicle turns, the connection angle between the drive shaft and the driven shaft changes. The driving force is transmitted from the driving shaft to the driven shaft. At this time, the boots are fitted with seal portions at both ends into fitting portions formed on a case of a constant velocity joint or a drive shaft, and a metal boot ring called a clamp is reduced in diameter by a tightening machine or the like. Then, it is attached to the constant velocity joint by being fastened to the outside of the seal portion (see, for example, Japanese Patent Application Laid-Open No. 200-9838).

Here, the boot has a sealing function of preventing the grease for lubricating the thread compensator from flowing out and preventing the entry of foreign substances such as water and dust. Further, the constant velocity joint has a function of rotating at a high speed and transmitting a driving force from the drive shaft to the driven shaft while changing the connection angle between the drive shaft and the driven shaft. For this reason, it is preferable that the boot ring used in the constant velocity joint has a simple ring shape without any protruding portion in order to avoid interference with surrounding members.

Incidentally, the boot is usually formed from a synthetic resin such as synthetic rubber or thermoplastic elastomer in consideration of heat resistance, cold resistance and durability. For this reason, the boot is made of metal made of a constant velocity joint because of the presence of grease. The seal portion slips between the drive shaft and the drive shaft, and the sealing performance is easily impaired.

On the other hand, a constant velocity joint is a joint that is attached to the connection between the drive shaft and the driven shaft to transmit the driving force of the engine from the drive shaft to the driven shaft. It is rotated at high speed. For this reason, as shown in FIG. 8, a load F1 acts on the seal portion 1a formed by the boot ring 2 on the small diameter portion side of the boot 1 due to the centrifugal force accompanying the high-speed rotation when the vehicle runs. For this reason, if the tightening force is small, the surface pressure of the booting 2 pressing the boot 1 is reduced, and the sealing function is impaired.

Moreover, when the vehicle turns, the drive shaft 3 is tilted with respect to the case, so that one of the boots 1 is pressed by the drive shaft 3 and the other is pulled by the drive shaft 3 as shown in FIG. Deform. Due to the reaction force F due to this deformation and the load F1 acting due to the centrifugal force, the load F2 acts on the seal portion 1a, and the sealing function is impaired. Although not shown, the blockage of the see-through function in the boot 1 due to such a load also poses a similar problem in the large-diameter portion-side seal portion 1a shown in FIG.

Therefore, the constant velocity joint forms a seal groove 4a along the entire circumference in a fitting portion 4 formed in a case or a drive shaft as shown in FIG. 9A, for example. Protrusions 4b are provided on both sides. As a result, the constant velocity joint regulates the sliding of the seal portion 1a, and the tightened boot ring 2 applies a required amount of surface pressure in consideration of the load F2 to both sides of the seal groove 4a. It is generated locally to ensure the sealability of the seal part 1a.

Alternatively, as shown in FIG. 9B, the constant velocity joint forms a sealing groove 4 c in the fitting portion 4 along the circumferential direction, and the projection 1 engages with the sealing groove 4 c in the boot 1. 1b is formed along the circumferential direction. As a result, the constant velocity joint regulates the slip of the seal portion 1a, and the required amount of surface pressure considering the loads Fl and F2 is applied to both sides of the seal groove 4c by the boot ring 2 to be fastened. It is generated locally to ensure the sealability of the seal part 1a. By the way, there is a problem in that the projection 4b is provided with the case and the drive shaft by cutting along with the groove 4a, and the processing cost is high. On the other hand, the sealing groove 4c can be processed at a low cost because the processing amount is smaller than the case of the projection 4b. In order to generate a high surface pressure by the boot ring at the part adjacent to the seal groove 4c, the boot.1 must be positioned inside the protrusion 1b with respect to the width of the seal grooves 4a, 4c. Need to be larger. For this reason, the outer peripheral surface of the boot, that is, the surface on which the boot ring is fastened, becomes convex, and the boot ring is displaced so as to slide on the convex slope during the tightening process, so that an appropriate surface pressure cannot be generated. there were.

The present invention has been made in view of the above, and an object of the present invention is to provide a buckling that can be used with an existing joint device and can generate a pre-designed surface pressure at a desired position in a well-balanced manner. And Disclosure of the invention

In the boot ring according to the present invention, the seal portions at both ends of the boot covering the joint device are respectively fitted to the fitting portions of the joint device having the seal grooves formed along the entire circumference, and then fastened to the seal portions. The boot ring for fixing the boot to the joint device, wherein a pressing portion for locally pressing the seal portion of the boot to both edges of the seal groove is provided over the entire inner surface. Features.

According to the present invention, the pressing portion locally presses the seal portions at both ends of the boot against both edges of the seal groove so that a predetermined surface pressure is generated in the seal portion in a well-balanced manner. The boot ring according to the present invention is characterized in that, in the above invention, the pressing portion is a single ridge that locally presses the seal portion toward each of the edges.

Further, the boot ring according to the present invention is characterized in that, in the above invention, the pressing portion is a two ridges for locally and individually pressing the above-mentioned sheinole portion to each of the edges. And BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view showing a boot ring according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view of the boot ring of FIG. 1 cut along a diameter, and FIG. FIG. 4 is a cross-sectional view showing a use state of the boot ring of FIG. 1, and FIG. 4 is a surface pressure distribution diagram showing a surface pressure in which a pressing portion of the boot ring locally presses the seal portion to a start portion of the seal groove. FIG. 5 is a perspective view showing a boot ring according to the second embodiment of the present invention. FIG. 6 is a sectional view showing a use state of the boot ring of FIG. Fig. 8 is a surface pressure distribution diagram showing the surface pressure at which the pressing portion of the boot ring locally presses the seal portion to the start portion of the seal groove.Fig. 8 shows the load acting on the seal portion of the boot at the constant velocity joint. FIG. 9A is a diagram illustrating a constant velocity joint. FIG. 9B is a view for explaining a first countermeasure that has been conventionally taken to ensure the sealing performance at the seal portion of the boot. FIG. 9 is a diagram for explaining a second countermeasure that has been conventionally performed. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of a boot ring according to the present invention will be described with reference to the drawings. The present invention is not limited by the embodiment.

(Embodiment 1)

First, a first embodiment of the boot ring according to the present invention will be described. FIG. 1 is a perspective view showing a boot ring 10 according to Embodiment 1 of the present invention.

The boot ring 10 is a seamless ring made of a metal rich in bullets, such as aluminum and stainless steel, and is fitted to the seal portions 1 a at both ends of the boot 1; | It is fixed. The boot ring 10 is wider than the seal groove 4 c formed along the circumferential direction in the fitting portion 4 (see FIG. 3) formed in the case or the drive shaft of the constant velocity joint, and As shown in FIGS. 1 and 2, two grooves are provided at predetermined intervals in the width direction at the portions corresponding to both edges Ps of the groove 4c. Are provided over the entire circumference of the inner surface. For this reason, the boot ring 10 is a concave groove in which the outer surface, which is the back surface of the pressing portion 10a, is depressed toward the inner surface. Each pressing portion 10a is arranged at the position of the edge Ps of the seal groove 4c or at a position slightly closer to the center of the seal groove 4c than that position. Therefore, the boot ring 10 locally presses the seal portion 1a toward the edge Ps of the seal groove 4c, as shown in FIG. The pressing portion 10a is configured such that when a tightening force is applied to the boot ring 10 from the outside toward the center in order to tighten the seal portion 1a of the boot 1, the tightening force is as shown in FIG. As shown, at the edges Ps on both sides of the seal groove 4c, the cut angle 切, which is the angle formed by the surface of the fitting portion 4 and the slope 4d of the seal groove 4c, is half the direction (2 Formed in a position and shape that acts on Θ / 2,) 8/2). By doing so, the booting 10 is preferable because the pre-designed surface pressure can act on both edges Ps of the seal groove 4c in a well-balanced manner. The pressing portion 10a may be formed in the boot ring 10 in advance, as shown in FIG. 1, or the boot ring 10 may be fastened to the sealing portion 1 of the boot 1 using a fastening jig. It may be formed when fastening to a.

Here, in FIG. 3, the boot 1 mainly shows the seal portion 1a attached to the case of the constant velocity joint, and the bellows portion is arranged on the right side. The edge Ps of the seal groove 4c is defined as the section of the fitting portion 4 formed on the case or the drive shaft of the constant velocity joint and cut along the longitudinal direction. 4 The intersection with the tangent of c.

The boot ring 10 configured as described above is reduced in diameter in the radial direction using a fastening jig, and is fastened to the seal portion 1a of the boot 1, thereby fixing the boot 1 to a constant velocity joint. I do. '

At this time, the boot ring 10 is provided with two pressing portions 10a over the entire circumference. For this reason, when the boot ring 10 is reduced in diameter in the radial direction, each pressing portion 10a points the sealing portion 1a of the boot 1 to each edge portion Ps of the sealing groove 4c by an arrow in FIG. Press in the θ / 2 and] 3/2 directions indicated by. As a result, the boot ring 10 becomes the fourth As shown in the figure, a pre-designed local surface pressure is applied to each edge Ps, and these edges Ps are locally pressed with substantially the same surface pressure.

For this reason, even if an external force acts on the boot ring 10 due to the operation of the constant velocity joint, the boot 1 has the sealing portion 1a with each edge of the seal groove 4c at a pre-designed surface pressure in consideration of the external force. The part P s is well pressed against the balance. Therefore, by using the boot ring 10, a gap is formed between the boot 1 and the fitting portion 4 so that grease leaks out, or the seal portion la is formed by the fitting formed on the case or the drive shaft. It is possible to suppress the occurrence of a situation in which it is not possible to generate an appropriate surface pressure at an appropriate position by being displaced in the longitudinal direction with respect to the portion 4. Since the boot ring 10 is a seamless ring and has a simple shape, it can be used as it is for a boot in an existing constant velocity joint.

(Embodiment 2)

Next, a second embodiment of the present invention will be described. The boot ring 10 according to the first embodiment is provided with two pressing portions 10a, but the boot ring according to the second embodiment is changed to a single pressing portion. FIG. 5 is a perspective view showing a boot ring 12 according to the second embodiment of the present invention. FIG. 6 is a sectional view showing a use state of the boot ring 12.

The boot ring 12 is a ring-shaped seam wrestling made of the same metal as the boot ring 10. The boot ring 12 is fastened to the seal portions 1a at both ends of the boot 1 to fix the boot 1 to the constant velocity joint. The boot ring 12 is wider than the groove 4c, and as shown in FIGS. 5 and 6, a single pressing portion 12a, whose entire width is convexly curved to the inner side, is entirely formed. It is provided over the circumference. Since the pressing portion 12a is curved inwardly convexly, when it is tightened to the sealing portion 1a, as shown in FIG. 6, the sealing portion 1a is formed into two edges on both sides of the sealing groove 4c. The part P s is pressed against the part P s in a well-balanced manner with a substantially equal surface pressure.

Here, similarly to the pressing portion 10a of the boot ring 10, the pressing portion 12a is formed in a shape acting on the edge Ps of the sealing groove 4c in the direction of half the cut angle. You Is preferred. The pressing portion 12 a may be formed in the boot ring 12 in advance, or may be formed when the boot ring 12 is fastened to the seal portion 1 a of the boot 1 using a fastening jig. May be performed.

The boot ring 12 configured as described above is reduced in diameter in the radial direction using a fastening jig and fastened to the seal portion 1a of the boot 1, thereby fixing the boot 1 to a constant velocity joint. I do. At this time, when the diameter of the boot ring 12 is reduced in the radial direction, the pressing portion 12a provided over the entire circumference presses the seal portion 1a of the boot 1 against the edge Ps. For this reason, even if the constant velocity joint is actuated and external force acts on the boot ring 12, the boot ring 12 as shown in FIG. s can be locally applied with a pre-designed substantially equal surface pressure in consideration of the external force.

Therefore, when the boot ring 12 is fastened to the seal portion 1 a of the boot 1, a gap is formed between the boot portion 1 and the fitting portion 4, and grease leaks out. However, it is possible to suppress the occurrence of such a situation that the fitting surface 4 is displaced in the longitudinal direction with respect to the fitting portion 4 formed on the case or the drive shaft, so that it is not possible to generate an appropriate surface pressure at an appropriate position.

The boot rings 10 and 12 of the first and second embodiments are seamless rings. However, the boot ring of the present invention may be a ring having a connecting portion such as an engagement structure or a joint structure in addition to the seamless ring.

Also, in the first and second embodiments, the case of a constant velocity joint has been described as a joint device using a boot ring. However, if the joint device uses a boot, the object to be used is limited to a constant velocity joint. Not something. Industrial applicability

INDUSTRIAL APPLICABILITY As described above, the boot ring according to the present invention is useful for generating a pre-designed surface pressure at a desired position in a well-balanced manner, and is particularly used for a portion for fixing a boot to an existing joint device. Suitable for

Claims

The scope of the claims

1. After fitting the seal portions at both ends of the boot covering the joint device to the fitting portions of the joint device in which the seal grooves are formed along the entire circumference, and then tightening the boot to the seal portion, A boot ring fixed to a joint device, wherein a boot portion for locally pressing the seal portion of the boot against both edges of the seal groove is provided around the entire inner surface. ring.

2. The boot ring according to claim 1, wherein the pressing portion is a single ridge that locally presses the seal portion toward each of the edges.

3. The boot ring according to claim 1, wherein the pressing portion is a pair of ridges that presses the seal portion locally and individually to the edge portions.