JP3227770U - Boot band - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tightening type boot band capable of stably applying a predetermined tightening force to an elastic boot for sealing.
A boot band has a band body made of a metal strip, a claw portion and a hole formed at one end and a hole on one side and the other end of the band body in the longitudinal direction, and a claw portion formed in the band body. A side view Ω-shaped protrusion 34 is provided between the hole and the protrusion 34 is crimped in a direction in which the peripheral length of the annular body formed by fitting the claw into the hole is reduced. As a result, a tightening force in the radial direction is applied to the cylindrical portion of the elastic boot for sealing arranged inside the annular body in the radial direction. The boot band has a relationship of 0.8d≤d1≤d, where d is the thickness of the metal strip (band body) and d1 is the wall thickness of the root portion 34c of the pair of leg portions 34a constituting the protrusion 34. Satisfy the formula.
[Selection diagram] Fig. 4

Description

The present invention relates to a boot band, and more particularly to a tightening type boot band that applies a tightening force in the radial direction to a cylindrical portion of an elastic boot for sealing by crimping a protrusion having an Ω-shaped side view.

The constant velocity universal joint, which is incorporated in the power transmission system of automobiles and various industrial machines and transmits rotational power at a constant velocity between the two shafts on the drive side and the driven side, has a bottomed tubular or bowl-shaped cup portion. It includes an outer joint member, a joint internal component arranged in the internal space of the cup portion, and a lubricant such as grease filled in the internal space of the cup portion. In order to prevent the lubricant from leaking to the outside and foreign matter from entering the internal space of the cup, the constant velocity universal joint is made of a tubular elastic boot for sealing (a tubular elastic material such as rubber or resin). Boots that function as a sealing member when fixed to the mounting target. Hereinafter, they are simply referred to as "boots").

The cylindrical portions provided at one end and the other end of the boot are generally fixed to the attachment target by tightening the outer diameter surface with a fastening member called a boot band. As the boot band, for example, a crimp-type boot band as described in Patent Document 1 below is widely used. Hereinafter, a known (conventional) crimpable boot band will be described in detail with reference to the drawings.

10 (a) and 10 (b) are a side view and a back view of the known crimp-type boot band 100 in an unfolded state (state before use), respectively. The boot band 100 includes a band body 101 made of a metal strip, and a claw portion 102, a hole portion 103, and a protrusion 104 formed in the band body 101. The claw portion 102, the hole portion 103, and the protrusion portion 104 are , Is formed by pressing a metal strip (band body 101). The band body 101 is overlapped with the first band 101A on the radial outer side of the first band 101A when the band body 101 is rolled along the longitudinal direction and deformed into an annular shape (see FIG. 11). It has two band portions 101B, and both band portions 101A and 101B are connected to each other via a step portion 101C. The claw portion 102 is formed on the first band portion 101A (the end on one side in the longitudinal direction of the band body 101), and the hole portion 103 is formed on the second band portion 101B (the end on the other side in the longitudinal direction of the band body 101). The protrusion 104 is arranged between the claw portion 102 and the hole portion 103. The protrusion 104 has a side view Ω shape having a pair of legs 104a and 104a and a top portion 104b connecting the tips of both legs 104a integrally. The boot band 100 having the above configuration is used, for example, as follows.

First, as shown in FIG. 11, the band main body 101 is rolled and the claw portion 102 is fitted into the hole portion 103 to form the annular body 100'. Next, as shown in FIG. 12, the protrusions 104 are crimped from both sides in the circumferential direction (one leg) in a state where the boots (not shown) and the attachment target thereof are placed on the radial inside of the annular body 100'. The protrusion 104 is plastically deformed so that the root portion 104c of the 104a and the base portion 104c of the other leg portion 104a are close to each other), and the peripheral length of the annular body 100'is reduced. Along with this, a tightening force in the radial direction is applied to the cylindrical portion of the boot, and the boot is fixed to the mounting target. After crimping the protrusion 104, the claw portion 102 and the hole portion 103 engage in the circumferential direction of the annular body 100', so that the expansion and deformation of the annular body 100'are restricted.

JP-A-2018-84306

The tightening force in the radial direction applied to the boot by the boot band 100 is affected by the wall thickness of the root portion 104c of the pair of leg portions 104a constituting the protrusion 104, and the wall thickness of the root portion 104c is particularly large. If it is insufficient, it may not be possible to provide the boot with the required tightening force. This is because when the thickness of the root portion 104c of the leg portion 104a is insufficient, the leg portion 104a is excessively deformed during the crimping of the protrusion 104 (the root portion 104c of one leg portion 104a). The amount of movement toward the other leg 104a and / or the amount of movement of the other leg 104a toward the one leg 104a is excessive).) The roots 104c of the legs 104a come into contact with each other. This is because it is not possible to determine whether or not the protrusion 104 can be crimped with a predetermined crimping force.

In view of such circumstances, it is an object of the present invention to provide a tightening type boot band capable of stably applying the required tightening force in the contraction direction to the elastic boot for sealing. To do.

The boot band according to the present invention, which was devised to achieve the above object, has a band body made of a metal strip, and claws and holes provided on one side and the other end in the longitudinal direction of the band body, respectively. The circumference of the annular body formed by fitting the claw portion into the hole portion is provided with a portion and a side view Ω-shaped protrusion provided on the band body and arranged between the claw portion and the hole portion. In a boot band that applies a tightening force in the radial direction to the cylindrical portion of the elastic boot for sealing arranged inside the annular body in the radial direction by crimping the protrusion in the decreasing direction, the thickness of the metal strip Is d, and when the wall thickness of the base portion of the pair of leg portions constituting the protrusion is d1, the relational expression of 0.8d ≦ d1 ≦ d is satisfied.

If the above relational expression is satisfied, when the protrusion is crimped after the formation of the annular body, the protrusion is excessively deformed to the extent that the roots of the pair of legs constituting the protrusion come into contact with each other. It can be prevented as much as possible. This makes it possible to crimp the protrusion with a predetermined crimping force (determine whether or not the protrusion has been crimped with a predetermined crimping force), so that the cylindrical portion of the elastic boot for sealing can be used. , The required tightening force in the reduced diameter direction can be stably applied.

When the band body is composed of a first band portion having a claw portion and a second band portion having a hole portion and being overlapped on the radial outer side of the first band portion when forming an annular body. The boot band according to the present invention has a maximum clearance width of a radial gap formed between the outer diameter surface of the first band portion and the inner diameter surface of the second band portion facing each other when the annular body is formed. Then, it is preferable that the relational expression of t ≦ 0.5 mm is satisfied.

In this way, the protrusion can be crimped with the contact point between the claw portion and the hole portion (second band portion) located on the root portion side of the claw portion. As a result, it is possible to prevent damage to the claw portion due to the large stress (moment load) acting on the claw portion as the protrusion is crimped. Therefore, a predetermined tightening force can be stably applied to the cylindrical portion of the boot.

The boot band having the above configuration has 0 <w, where w is the clearance width of the circumferential gap (gap in the circumferential direction of the annular body) formed between the claw portion and the hole portion when the annular body is formed. It is preferable that the relational expression of ≦ 0.8 mm is satisfied. By doing so, the claw portion can be smoothly fitted to the corresponding hole portion (the annular body can be easily formed), and the claw portion is damaged when the protrusion is crimped after the formation of the annular body. The possibility of equality can be effectively reduced.

The boot band according to the present invention is, for example, a constant velocity universal joint (a fixed constant velocity universal joint that allows only angular displacement, or a sliding constant velocity universal joint that allows both angular displacement and axial displacement. It can be used as a boot band for applying a tightening force in the radial direction to the cylindrical portion of the elastic boot for sealing attached to the elastic boot (whether or not there is one). In addition to this, the boot band according to the present invention applies a tightening force in the radial direction to, for example, a cylindrical portion of an elastic boot for sealing (boot for actuator) mounted on an electric actuator equipped with a ball screw. Can be used as a boot band for.

From the above, according to the present invention, it is possible to realize a tightening type boot band capable of stably applying a predetermined tightening force to the cylindrical portion of the elastic boot for sealing.

It is a vertical cross-sectional view which shows an example of the constant velocity universal joint with a boot which used the boot band which concerns on embodiment of this invention. (A) is a side view of the boot band according to the embodiment of the present invention in an unfolded state, and (b) is a bottom view of (a). It is a side view of the annular body formed by deforming the boot band shown in FIG. 2 into an annular shape. It is an enlarged view of part A of FIG. (A) is an enlarged view of part B of FIG. 3, (b) is a plan view of (a) as viewed from the direction of arrow X shown in the figure, and (c) is a view of (b). FIG. 5 is an enlarged cross-sectional view taken along the line YY. It is a partially enlarged side view of the annular body formed by deforming a boot band which does not adopt this invention into an annular form. It is a figure for demonstrating the behavior when the annular body shown in FIG. 3 is crimped. It is a partially enlarged plan view of an annular body formed by deforming a boot band which does not adopt the present invention into an annular shape. It is a side view of the boot band made by crimping the annular body shown in FIG. (A) is a side view of a conventional boot band in an unfolded state, and (b) is a bottom view of (a). It is a side view of the annular body formed by deforming the boot band shown in FIG. 10 into an annular shape. It is a side view which shows the state which the annular body shown in FIG. 11 was crimped.

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

FIG. 1 shows an example of a constant velocity universal joint 1 with boots equipped with elastic boots for sealing. The constant velocity universal joint 1 constitutes a drive shaft that transmits rotational power (torque) output from a drive source such as an engine or an electric motor mounted on the chassis of an automobile to wheels, and is incorporated in the automobile. In this state, it is placed on the wheel side and allows only angular displacement.

That is, the constant velocity universal joint 1 shown in FIG. 1 is a so-called fixed constant velocity universal joint, and is an outer joint member 2 having a cup portion 6 and a shaft portion 7, and the inside of the joint housed in the inner circumference of the cup portion 6. Equipped with parts. The joint internal parts are formed on the inner joint member 3 in which the shaft member 10 is connected to the center hole so that torque can be transmitted, the outer track groove 8 formed on the inner diameter surface of the cup portion 6, and the outer diameter surface of the inner joint member 3. A ball 4 arranged in an arc-shaped ball track formed by the inner track groove 9 and transmitting torque between the outer joint member 2 and the inner joint member 3 and a cage 5 holding the ball 4 are provided. Be prepared. The ball track and the ball 4 are arranged at a plurality of locations (for example, 6 locations) separated in the circumferential direction.

Although not shown, the internal space of the cup portion 6 is filled with a lubricant such as grease. In order to prevent the lubricant from leaking to the outside and foreign matter from entering the joint, a tubular elastic boot 20 for sealing (hereinafter, simply referred to as "boot 20") is provided between the cup portion 6 and the shaft member 10. ing. The boot 20 is a resin boot molded by using a resin material containing a thermoplastic elastomer as a main component, and is a large-diameter cylindrical portion 21 fixed to the outer diameter surface of the cup portion 6 and the outside of the shaft member 10. A small-diameter cylindrical portion 22 fixed to the radial surface and a bellows portion 23 connecting both cylindrical portions 21 and 22 are integrally provided. The bellows portion 23 elastically expands and contracts and bends and deforms as the outer joint member 2 and the inner joint member 3 (shaft member 10) are relatively angularly displaced.

The large-diameter cylindrical portion 21 of the boot 20 is fixed to the cup portion 6 by a tightening force in the diameter-reducing direction applied from the boot band 30 mounted on the outer peripheral surface thereof. Further, the small-diameter cylindrical portion 22 of the boot 20 is fixed to the shaft member 10 by a tightening force in the diameter-reducing direction applied from the boot band 40 mounted on the outer peripheral surface thereof. As the boot bands 30 and 40, a tightening type boot band to which the present invention is applied is used.

Hereinafter, the boot band according to the embodiment of the present invention will be described in detail. In the following, of the two boot bands 30 and 40 described above, the boot band 30 that applies a tightening force in the diameter reduction direction to the large-diameter cylindrical portion 21 of the boot 20 will be described as a typical example. It has the same configuration as the boot band 30 except that the lengths (diameters) are different from each other.

2 (a) and 2 (b) are a side view and a lower surface (back surface) view of the boot band 30 according to the embodiment of the present invention in the deployed state, respectively. The boot band 30 has the same configuration as the conventional boot band 100 described with reference to FIG. 10 and the like. That is, the boot band 30 includes a band main body 31 made of a metal strip, and a claw portion 32, a hole portion 33, and a protrusion 34 formed in the band main body 31 by pressing the metal strip.

The band main body 31 is overlapped with the first band portion 31A on the radial outer side of the first band portion 31A when the band main body 31 is rolled along the longitudinal direction and deformed into an annular shape (see FIG. 3). The second band portion 31B and the step portion 31C connecting both band portions 31A and 31B are integrally provided. The height difference of the step portion 31C is substantially the same as the plate thickness d of the metal strip. The "one side in the longitudinal direction" and the "other side in the longitudinal direction" used in the following description refer to the side where the first band portion 31A is provided (the left side of the paper in FIG. 2) and the second band portion 31B, respectively. This is the provided side (right side of the paper in FIG. 2).

The claw portion 32 is formed near the end portion on one side in the longitudinal direction of the first band portion 31A. In the present embodiment, the three claw portions 32a, 32b, and 32c are formed by arranging them in a row along the longitudinal direction of the band main body 31. Of the three claws, the claws 32a and 32b are formed by raising a part of the band body 31 (first band 31A) toward the surface 31a, and the claws 32c located on one side in the longitudinal direction. Is formed by bending (cutting up) a part of the band body 31 toward the surface 31a.

The hole 33 is formed near the end of the second band 31B on the other side in the longitudinal direction. In the present embodiment, the holes 33a, 33b, 33c to which the claws 32a, 32b, 32c are fitted when the annular body 30'shown in FIG. 3 is formed are arranged in a row along the longitudinal direction of the band body 31. Is forming. The holes 33a to 33c are through holes opened in the front surface 31a and the back surface 31b of the band body 31.

The protrusion 34 is formed between the claw portion 32 and the hole portion 33, specifically, in a region of the second band portion 31B on one side in the longitudinal direction with respect to the hole portion 33. The protrusion 34 has a side view Ω shape including a pair of leg portions 34a and 34a provided apart from each other in the longitudinal direction and a top portion 34b connecting the tips of both leg portions 34a. The separation distance between one leg 34a and the other leg 34a is set according to the tightening force to be applied to the tightening target (here, the large-diameter cylindrical portion 21 of the boot 20).

A bulging portion 35 is formed between the claw portion 32 and the protruding portion 34. The bulging portion 35 is formed by forming two parallel cuts extending in the longitudinal direction of the band main body 31 and then bulging the portion between the two cuts toward the surface side 31a. The cut is formed so that one end is located at one end of the second band 31B in the longitudinal direction and the other end is located within the range of the first band 31A. By forming such a bulging portion 35, a band-shaped groove portion extending in the longitudinal direction of the band main body 31 is defined on the back surface side of the bulging portion 35. This groove functions as an accommodation groove 37 into which the insertion piece 36 formed at one end in the longitudinal direction of the band main body 31 is inserted (accommodated) when the annular body 30'shown in FIG. 3 is formed.

The boot band 30 having the above configuration is used, for example, as follows.

First, the band body 31 is rolled along its longitudinal direction, and the claws 32a to 32c corresponding to the holes 33a to 33c are fitted to each other to deform the band body 31 into an annular shape. As a result, as shown in FIG. 3, an annular body 30'in which the second band portion 31B is overlapped on the radial outer side of the first band portion 31A is formed. At this time, the insertion piece 36 formed at one end of the band main body 31 in the longitudinal direction is accommodated in the band-shaped accommodating groove 37. Therefore, the tightening of the large-diameter cylindrical portion 21 of the boot 20 performed by crimping the protrusion 34 is the state in which the insertion piece 36 is accommodated in the accommodating groove 37, that is, the surface for tightening the large-diameter cylindrical portion 21 of the boot 20. It can be carried out in a state where there is no step on the inner diameter surface of the annular body 30'. As a result, the large-diameter cylindrical portion 21 of the boot 20 can be tightened with high accuracy.

Next, the large-diameter cylindrical portion 21 of the boot 20 and the cup portion 6 of the outer joint member 2 to be attached to the large-diameter cylindrical portion 21 of the boot 20 are placed on the radial inner side of the annular body 30'. By crimping the protrusion 34 from both sides in the circumferential direction, the protrusion 34 is plastically deformed so that the root portion 34c of one leg portion 34a and the root portion 34c of the other leg portion 34a approach each other. Along with this, the peripheral length of the annular body 30'is reduced and a tightening force in the diameter reduction direction is applied to the large diameter cylindrical portion 21 of the boot 20, and as a result, the large diameter cylindrical portion 21 is placed on the outer diameter surface of the cup portion 6. On the other hand, it is fixed. After the protrusions 34 are crimped, the claws 32a to 32c and the corresponding holes 33a to 33c are engaged with each other in the circumferential direction of the annular body 30', so that the annular body 30'is unfolded and deformed. Be regulated.

The basic structure and usage mode of the boot band 30 according to the embodiment of the present invention are as described above, and the boot band 30 has a characteristic configuration as shown below.

First, as shown in FIGS. 2 to 4, the thickness of the metal strip (band body 31 composed of the band main body 31) is d, and the wall thickness of the root portion 34c of the pair of leg portions 34a constituting the protrusion 34 is d1. Then, the protrusion 34 is formed so as to satisfy the relational expression of 0.8d ≦ d1 ≦ d, preferably 0.85d ≦ d1 ≦ d.

By doing so, it is possible to secure the rigidity required for the protrusion 34 when the protrusion 34 is crimped after the formation of the annular body 30'shown in FIG. 3 (see FIG. 9), so that one leg portion 34a It is possible to prevent the protrusion 34 from being significantly deformed to the extent that the root portion 34c of the head portion 34c and the root portion 34c of the other leg portion 34a come into contact with each other. As a result, the protrusion 34 can be crimped with a predetermined crimping force, so that the required tightening force in the diameter reduction direction can be stably applied to the large-diameter cylindrical portion 21 of the boot 20. ..

Further, when the annular body 30'shown in FIG. 3 is formed by rolling the band body 31 and fitting the claw portions 32 (32a to 32c) into the corresponding hole portions 33 (33a to 33c), B in FIG. As shown in FIG. 5A, which is an enlarged view of the portion, a radial gap Gr is formed between the outer diameter surface of the first band portion 31A and the inner diameter surface of the second band portion 31B facing each other. At this time, for example, as shown in FIG. 6, when a wide radial gap Gr having a maximum gap width t exceeding 0.5 mm is formed between both band portions 31A and 31B, the claw portion 32 (particularly 32c) ) And the contact point P between the second band portion 31B and the second band portion 31B are located on the tip end side of the claw portion 32c. Therefore, when the protrusion 34 is crimped in this state, a large stress (a stress along the circumferential direction of the annular body 30'indicated by the black arrow in FIG. 6) is applied to the claw portion 32 (particularly 32c) due to the crimping. It can be said that it is a load), which increases the possibility that the claw portion 32 (particularly 32c) is damaged.

On the other hand, in the boot band 30 of the present embodiment shown in FIG. 5A, the maximum gap width t of the radial gap Gr formed between the two band portions 31A and 31B when the annular body 30'is formed is 0.5 mm. It is configured to be less than or equal to (t ≦ 0.5 mm), more preferably 0.35 mm or less (t ≦ 0.35 mm). In this way, as is clear from comparing FIGS. 5A and 6 with the contact point between the claw portion 32c and the second band portion 31B located on the root portion side of the claw portion 32c. The protrusion 34 can be crimped. As a result, it is possible to prevent damage to the claw portion 32 due to a large stress acting on the claw portion 32 (particularly 32c) as the protrusion 34 is crimped. Therefore, a predetermined tightening force can be stably applied to the large-diameter cylindrical portion 21 of the boot 20.

In order to satisfy the above relational expression of t ≦ 0.5 mm (preferably t ≦ 0.35 mm), in the present embodiment, the longest of the three claw portions 32a to 32c formed on the first band portion 31A The shape of the claw portion 32c located on one side in the direction has been devised. Specifically, as shown in FIG. 5C, “h ≦ d + 0.5 mm” when the separation distance (shortest separation distance) of the claw portion 32c from the surface 31a of the first band portion 31A is h. It is formed in a substantially L-shaped cross section (inverted L-shaped shape) provided with a bent portion 32d having a surface substantially parallel to the surface 31a, which satisfies the relational expression of. Explaining the shape of the claw portion 32c in more detail, the claw portion 32c has a standing portion having an angle of approximately 90 ° with respect to the surface 31a of the first band portion 31A, and the tip of the standing portion is bent or curved. It is formed in a substantially L-shaped cross section including a bent portion 32d forming an angle of approximately 90 ° with respect to the standing portion.

By the way, in the boot band 30 of the present embodiment used in a state where the claw portion 32 is fitted to the hole portion 33, the longitudinal dimension of each of the hole portions 33a to 33c is set to the longitudinal dimension of the corresponding claw portions 32a to 32c. It is necessary to set the above. However, when the longitudinal dimensions of the corresponding claws and holes are the same (as shown in FIG. 8, when the annular body 30'is formed, a circumferential gap is formed between the corresponding claws and the holes. If not), the crimping operation of the protrusion 34, which is performed after the formation of the annular body 30', may not be properly performed, and a predetermined tightening force may not be applied to the large-diameter cylindrical portion 21 of the boot 20.

The reason why the crimping operation of the protrusion 34 may not be properly performed when the above-mentioned circumferential gap is not formed is as follows. First, due to the structure of the boot band 30, immediately after the crimping work of the protrusion 34 is started, as shown in FIG. 7, the second band portion 31B is separated from the first band portion 31A (outward in the radial direction). Due to the elastic deformation, the claws 32 (here 32a, 32b) are separated from the holes 33 (here, 33a, 33b). As the crimping work of the protrusion 34 progresses (the amount of crimping increases), the second band portion 31B elastically deforms in the direction approaching the first band portion 31A (inward in the radial direction), so that the claw portion The 32a and 32b will be refitted into the corresponding hole portions 33a and 33b, but as the crimping work of the protrusion 34 progresses, the first band portion 31A (the claw portion 32 formed in the claw portion 32) Since the circumferential relative position of the second band portion 31B (the hole portion 33 formed in the hole portion 33) changes with respect to the above, when the corresponding claw portion 32 and the hole portion 33 have the same longitudinal dimension, the hole portion 33 (the hole portion 33) Here, it becomes difficult to refit the corresponding claw portion 32 (here, 32a, 32b) with respect to 33a, 33b).

The problem as described above is that the longitudinal dimension of the hole 33 is made larger than the longitudinal dimension of the corresponding claw portion 32 (the circumference formed between the corresponding hole portion and the claw portion when the annular body 30'is formed). It can be solved by increasing the gap width of the directional gap). However, as the gap width of the circumferential gap becomes larger, the amount of relative movement of the first band portion 31A and the second band portion 31B caused by crimping the protrusion 34, and eventually the claw after crimping the protrusion 34. Since the circumferential load applied to the portion 32 (particularly 32c) becomes large, the possibility that the claw portion 32 (particularly 32c) is damaged increases.

Therefore, as shown in FIG. 5B, the boot band 30 of the present embodiment is located between the corresponding claw portions 32 (here, 32a and 32b) and the hole portions 33a and 33b when the annular body 30'is formed. When the circumferential gap Gc is formed in each of the above and the gap width of the circumferential gap Gc is w, the relational expression of 0 <w ≦ 0.8 mm, more preferably 0.1 mm ≦ w ≦ 0.6 mm is satisfied. The longitudinal dimensions of the claw portions 32a and 32b and the hole portions 33a and 33b are set so as to be obtained. As a result, the claw portion 32 can be smoothly fitted to the corresponding hole portion 33 (the annular body 30'can be easily formed), and the claw portion 32 (particularly 32c) is damaged when the protrusion 34 is crimped. Since the possibility of equalization can be effectively reduced, it is advantageous in stably applying a predetermined tightening force to the large-diameter cylindrical portion 21 of the boot 20.

Combined with the above actions and effects, the boot band 30 according to the embodiment of the present invention is characterized in that a predetermined tightening force can be stably applied to the large-diameter cylindrical portion 21 of the boot 20. Have.

Although the boot band 30 for the constant velocity universal joint according to the embodiment of the present invention has been described above, the embodiment of the present invention is not limited to this.

For example, in the embodiment described above, the claw portion 32 and the hole portion 33 are provided three by three along the longitudinal direction of the band main body 31 (circumferential direction of the annular body 30'), but the band main body 31 has an annular shape. As long as the shape can be maintained when deformed, the number of claws 32 and the holes 33 formed and the arrangement mode can be arbitrarily set.

Further, in the above, the case where the boot band 30 according to the embodiment of the present invention is used when fixing the resin boot 20 to the mounting target has been described, but the boot band 30 fixes the rubber boot to the mounting target. Of course, it is also possible to use it at the time.

Further, in the above, the case where the present invention is applied to the constant velocity universal joint constituting the drive shaft and the boot band for fixing the boot to the shaft member has been described, but the present invention has described the case where the present invention constitutes a propeller shaft and the like. It can also be applied to boot bands for fixing boots to universal joints and shaft members. Further, the present invention can also be applied to a boot band for fixing a cylindrical portion of a boot in which a screw shaft of a ball screw is housed to an attachment target in, for example, an electric actuator provided with a ball screw.

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

1 Constant velocity universal joint 2 Outer joint member 6 Cup part 20 Boots (elastic boots for sealing)
21 Large diameter cylindrical part (cylindrical part)
22 Small diameter cylindrical part (cylindrical part)
30 Boot band 31 Band body 31A 1st band 31B 2nd band 32 Claw 33 Hole 34 Protrusion 34a Leg 34c Root d Metal strip thickness d1 Root wall thickness Gr Radial gap Gc circumference Directional gap t Maximum clearance width of radial gap w Gap width of circumferential gap

Claims (3)

A band body made of a metal strip, claws and holes provided on one side and the other end in the longitudinal direction of the band body, and between the claws and the holes provided on the band body. Equipped with a side view Ω-shaped protrusion arranged in
An elastic boot for sealing that is arranged radially inside the annular body by crimping the protrusion in a direction in which the peripheral length of the annular body formed by fitting the claw portion into the hole portion decreases. In a boot band that applies a tightening force in the radial direction to the cylindrical part,
When the thickness of the metal strip is d and the thickness of the roots of the pair of legs constituting the protrusion is d1, the boots satisfy the relational expression of 0.8d ≦ d1 ≦ d. band. The band body includes a first band portion having the claw portion and a second band portion having the hole portion and being overlapped on the radial outer side of the first band portion when the annular body is formed.
When the maximum clearance width of the radial gap formed between the outer diameter surface of the first band portion and the inner diameter surface of the second band portion facing each other at the time of forming the annular body is t, t ≦ The boot band according to claim 1, which satisfies the relational expression of 0.5 mm. Claim 1 or 2 satisfying the relational expression of 0 <w≤0.8 mm, where w is the width of the circumferential gap formed between the claw portion and the hole portion when the annular body is formed. The listed boot band.

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