CN215950181U

CN215950181U - Protective cover belt

Info

Publication number: CN215950181U
Application number: CN202121200928.6U
Authority: CN
Inventors: 此本武美; 村上裕志
Original assignee: NTN Corp
Current assignee: NTN Corp
Priority date: 2020-06-12
Filing date: 2021-05-31
Publication date: 2022-03-04
Anticipated expiration: 2031-05-31
Also published as: JP3227770U; BR212022024865U2; WO2021251067A1

Abstract

The utility model aims to provide a caulking-type protective cover band which can stably apply required fastening force in a diameter reducing direction to an elastic protective cover for sealing. The shield band (30) is provided with claw portions (32) formed on a band main body (31) formed by a metal band plate, a hole portion (33), and a protruding portion (34) which is in an omega shape in side view, and the shield band (30) is used for caulking the protruding portion (34) in a direction of reducing the circumference of an annular body (30 ') formed by fitting the claw portions (32) into the hole portion (33), thereby applying fastening force in a reducing direction to a cylindrical portion (21) of a protective cover (20) arranged on the radial inner side of the annular body (30'). The protective cover tape (30) satisfies the relational expression of 0.8 d.ltoreq.d 1.ltoreq.d, where d is the thickness of the tape main body (31) and d1 is the thickness of the root portion (34c) of the pair of leg portions (34a) constituting the protrusion (34).

Description

Protective cover belt

Technical Field

The present invention relates to a protector band, and more particularly to a caulking-type protector band in which a protrusion portion having a Q-shape in a side view is caulked to apply a fastening force in a diameter reduction direction to a cylindrical portion of an elastic sealing protector.

Background

A constant velocity universal joint which is incorporated in a power transmission system of an automobile, various industrial machines, or the like and transmits rotational power between two shafts on a drive side and a driven side at a constant velocity, the constant velocity universal joint comprising: an outer joint member having a bottomed cylindrical or bowl-shaped cup portion; a coupling inner member disposed in an inner space of the cup portion; and a lubricant such as grease filled in the inner space of the cup-shaped portion. In order to prevent external leakage of the lubricant and intrusion of foreign matter into the inner space of the cup portion, a cylindrical sealing elastic boot (a boot that functions as a sealing member by being formed in a cylindrical shape from an elastic material such as rubber or resin and fixed to an object to be attached, hereinafter also simply referred to as a "boot") is mounted on the constant velocity universal joint.

The cylindrical portion provided at each of the one end and the other end of the protector is generally fixed to the mounting object by fastening the outer diameter surface thereof with a fastening member called a protector band. As the cover tape, for example, a caulking-type cover tape as described in patent document 1 below is widely used. A known (conventional) caulking-type protective cover tape will be described in detail below with reference to the drawings.

Fig. 10A and 10B are a side view and a back view of a known caulking-type boot strap 100 in an expanded state (state before use), respectively. The protective cover band 100 includes a band main body 101 made of a metal band plate, and claw portions 102, holes 103, and protrusions 104 formed in the band main body 101, and the claw portions 102, the holes 103, and the protrusions 104 are formed by press working the metal band plate (the band main body 101). The belt main body 101 has: a first strap part 101A; and a second band part 101B that overlaps the first band part 101A radially outward when the band body 101 is rolled up in the longitudinal direction and deformed into an annular form (see fig. 11), and the two

band parts

101A and 101B are connected via a stepped part 101C. The claw 102 is formed in the first band part 101A (the end portion on one side in the longitudinal direction of the band main body 101), the hole 103 is formed in the second band part 101B (the end portion on the other side in the longitudinal direction of the band main body 101), and the protrusion 104 is disposed between the claw 102 and the hole 103. The protrusion 104 integrally has the following members so as to be formed in a Q-shape in side view: a pair of legs 104A, 104A; and a top portion 104b connecting top ends of the two leg portions 104 a. The protective cover tape 100 having the above-described structure is used in the following manner, for example.

First, as shown in fig. 11, the band body 101 is rolled up and the hook 102 is fitted into the hole 103, thereby forming the ring body 100'. Next, in a state where a protective cover (not shown) and its attachment target are arranged to overlap each other on the radially inner side of the annular body 100 ', as shown in fig. 12, the projections 104 are caulked from both sides in the circumferential direction (the projections 104 are plastically deformed so that the root portions 104c of the one leg portion 104a and the root portions 104c of the other leg portion 104a are close to each other), and the circumferential length of the annular body 100' is reduced. Accordingly, a tightening force in the diameter reduction direction is applied to the cylindrical portion of the protective cover, and the protective cover is fixed to the attachment object. After the projection 104 is caulked, the claw 102 and the hole 103 are engaged with each other in the circumferential direction of the annular body 100 ', and therefore, the expansion deformation of the annular body 100' is restricted.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2018-84306

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

The above-described fastening force in the diameter-reducing direction applied to the boot by the boot strap 100 is affected by the thickness of the root portions 104c of the pair of leg portions 104a constituting the protrusion 104, and particularly when the thickness of the root portions 104c is insufficient, there is a possibility that a necessary fastening force cannot be applied to the boot. This is because, when the thickness of the root portion 104c of the leg portion 104a is insufficient, the leg portions 104a are excessively deformed (the amount of movement of the root portion 104c of the one leg portion 104a toward the other leg portion 104a and/or the amount of movement of the root portion 104c of the other leg portion 104a toward the one leg portion 104a becomes excessively large) during the caulking process of the projection portion 104, and the root portions 104c of the leg portions 104a are brought into contact with each other, and therefore, it is not possible to determine whether or not the projection portion 104 can be caulked with a predetermined caulking force.

In view of the above circumstances, an object of the present invention is to provide a caulking-type boot band capable of stably applying a required fastening force in a diameter-reducing direction to an elastic boot for sealing.

Means for solving the problems

In order to achieve the above object, the present invention provides a protective cover tape comprising: a belt main body composed of a metal belt plate; a claw portion and a hole portion which are respectively arranged at the end part of one side of the belt main body in the length direction and the other side of the belt main body in the length direction; and a Q-shaped protrusion portion provided between the claw portion and the hole portion in a side view, the shield band being configured to apply a tightening force in a diameter reduction direction to a cylindrical portion of the elastic sealing shield disposed radially inward of the annular body by caulking the protrusion portion in a direction in which a circumferential length of the annular body formed by fitting the claw portion to the hole portion is reduced, wherein a relational expression of 0.8 d.ltoreq.d 1.ltoreq.d is satisfied where a plate thickness of the metal band plate is d and a wall thickness of a root portion of a pair of leg portions constituting the protrusion portion is d 1.

If the above relational expression is satisfied, when the annular body is formed and then the protrusion is caulked, the protrusion can be prevented from being excessively deformed to such an extent that the root portions of the pair of leg portions constituting the protrusion contact each other as much as possible. Accordingly, the projection portion can be caulked with a predetermined caulking force (it is determined whether or not the projection portion is caulked with the predetermined caulking force), and therefore, a necessary tightening force in the diameter reduction direction can be stably applied to the cylindrical portion of the elastic sealing boot.

Preferably, the belt main body is configured to include: a first band portion having a claw portion; and a second band part having a hole part and overlapping the radial outer side of the first band part when the annular body is formed, wherein when the maximum gap width of the radial gap formed between the outer diameter surface of the first band part and the inner diameter surface of the second band part facing each other when the annular body is formed is t, the relational expression that t is less than or equal to 0.5mm is satisfied.

In this way, the projecting portion can be caulked in a state where the contact point between the claw portion and the hole portion (second band portion) is located on the root side of the claw portion. This makes it possible to prevent the claw portion from being damaged or the like as much as possible due to a large stress (moment load) applied to the claw portion as the projection portion is caulked. Therefore, a predetermined tightening force can be stably applied to the cylindrical portion of the protective cover.

Preferably, in the formation of the annular body, the protective cover band having the above-described configuration satisfies the relational expression of 0 < w.ltoreq.0.8 mm, where w is a gap width of a circumferential gap (a gap in the circumferential direction of the annular body) formed between the claw portion and the hole portion. In this way, the claw portions can be smoothly fitted into the corresponding hole portions (the annular body can be easily formed), and when the projection portions are caulked after the annular body is formed, the possibility of breakage or the like of the claw portions can be effectively reduced.

The boot band of the present invention can be used, for example, as a boot band for applying a tightening force in a diameter reduction direction to a cylindrical portion of an elastic boot for sealing which is assembled to a constant velocity universal joint (may be a fixed type constant velocity universal joint which allows only angular displacement, or may be a plunging type constant velocity universal joint which allows both angular displacement and axial displacement). In addition to the above, the boot strap of the present invention can be used as a boot strap for applying a tightening force in a diameter reduction direction to a cylindrical portion of an elastic sealing boot (an actuator boot) attached to an electric actuator including a ball screw, for example.

Effect of the utility model

As described above, according to the present invention, it is possible to realize a caulking-type protector band that can stably apply a predetermined fastening force to the cylindrical portion of the elastic protector for sealing.

Drawings

Fig. 1 is a longitudinal sectional view showing an example of a constant velocity universal joint with a boot using a boot band according to an embodiment of the present invention.

Fig. 2A is a side view of the protector strap of the embodiment of the present invention in an unfolded state.

Fig. 2B is a bottom view of fig. 2A.

Fig. 3 is a side view of an annular body formed by deforming the protective cover band shown in fig. 2A into an annular form.

Fig. 4 is an enlarged view of a portion a of fig. 3.

Fig. 5A is an enlarged view of a portion B of fig. 3.

Fig. 5B is a plan view of fig. 5A as viewed from the direction of arrow X shown in fig. 5A.

Fig. 5C is an enlarged cross-sectional view taken along the Y-Y line of fig. 5B.

Fig. 6 is a partially enlarged side view of an annular body formed by deforming a protective cover tape not using the present invention into an annular form.

Fig. 7 is a view for explaining a behavior of the annular body shown in fig. 3 when caulking is performed.

Fig. 8 is a partially enlarged plan view of an annular body formed by deforming a protective cover tape not employing the present invention into an annular form.

Fig. 9 is a side view of the protective cover band obtained by caulking the annular body shown in fig. 3.

Fig. 10A is a side view of the conventional cover tape in an expanded state.

Fig. 10B is a bottom view of fig. 10A.

Fig. 11 is a side view of an annular body formed by deforming the protective cover band shown in fig. 10A into an annular form.

Fig. 12 is a side view showing a state where the annular body shown in fig. 11 is subjected to caulking.

Description of reference numerals:

1 constant velocity universal joint

2 outer coupling member

6 cup-shaped part

20 protective cover (elastic protective cover for sealing)

21 major diameter cylinder part (Cylinder part)

22 minor-diameter cylindrical part (cylindrical part)

30 protective cover belt

31 belt body

31A first belt part

31B second band part

32 claw part

33 hole part

34 projecting part

34a leg

34c root of Siberian ginseng

d thickness of metal strip

Wall thickness of root of d1

Gr radial clearance

Gc circumferential gap

t maximum gap width of radial gap

w gap width of the circumferential gap.

Detailed Description

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 a boot, to which an elastic boot for sealing is attached. 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 a chassis of an automobile to wheels, and is arranged on the wheel side in a state of being assembled to the automobile so as to allow only angular displacement.

That is, the constant velocity universal joint 1 shown in fig. 1 is a so-called fixed type constant velocity universal joint, and includes: an outer joint member 2 having a cup-shaped portion 6 and a shaft portion 7; and a coupling inner member housed in an inner periphery of the cup portion 6. The coupling inner member includes: an inner coupling member 3 having a shaft member 10 connected to a center hole so as to be capable of transmitting torque; balls 4 which are disposed in arc-shaped ball tracks formed by outer track grooves 8 formed in the inner diameter surface of the cup-shaped portion 6 and inner track grooves 9 formed in the outer diameter surface of the inner joint member 3, and which transmit torque between the outer joint member 2 and the inner joint member 3; and a retainer 5 that retains the balls 4. The ball grooves and the balls 4 are arranged at a plurality of positions (for example, 6 positions) at intervals in the circumferential direction.

Although not shown, the inner space of cup-shaped portion 6 is filled with a lubricant such as grease. In order to prevent external leakage of the lubricant and intrusion of foreign matter from the outside of the coupling, a cylindrical elastic sealing boot 20 (hereinafter, simply referred to as "boot 20") is provided between the cup portion 6 and the shaft member 10. The boot 20 is a resin boot molded by using a resin material containing a thermoplastic elastomer as a main component, and integrally includes: a large-diameter cylindrical portion 21 fixed to an outer diameter surface of the cup portion 6; a small-diameter cylindrical portion 22 fixed to an outer diameter surface of the shaft member 10; and a bellows portion 23 connecting the two cylinder portions 21, 22. As the outer joint member 2 and the inner joint member 3 (shaft member 10) are angularly displaced relative to each other, the bellows portions 23 elastically expand and contract and are bent.

The large diameter cylindrical portion 21 of the boot 20 is fixed to the cup portion 6 by a tightening force in the diameter reduction direction applied by the boot band 30 attached to the outer circumferential surface thereof. The small-diameter cylindrical portion 22 of the protective cover 20 is fixed to the shaft member 10 by a tightening force in the diameter-reducing direction applied by the protective cover tape 40 attached to the outer circumferential surface thereof. As the

cover tapes

30 and 40, a caulking-type cover tape to which the present invention is applied is used.

Hereinafter, the protective cover tape according to the embodiment of the present invention will be described in detail. Hereinafter, a typical example of the boot strap 30 that applies a tightening force in a diameter reduction direction to the large diameter cylindrical portion 21 of the boot 20, out of the two

boot straps

30 and 40, will be described, and the boot strap 40 has substantially the same configuration as the boot strap 30 except that the circumferential length (diameter) thereof is different from that of the boot strap 30.

Fig. 2A and 2B are a side view and a top (back) view of the protection cover band 30 according to the embodiment of the present invention in an expanded state. The protective cover tape 30 has the same configuration as the conventional protective cover tape 100 described with reference to fig. 10 and the like. That is, the protective cover band 30 includes a band main body 31 made of a metal band plate, and claw portions 32, holes 33, and protrusions 34 formed in the band main body 31 by press working the metal band plate.

The belt main body 31 integrally has: the first belt portion 31A; a second band part 31B that overlaps the first band part 31A on the outside in the radial direction when the band body 31 is rolled up in the longitudinal direction thereof and deformed into an annular form (see fig. 3); and a step portion 31C connecting the both

belt portions

31A and 31B. The step 31C has a height difference substantially equal to the plate thickness d of the metal strip. The "one longitudinal side" and the "other longitudinal side" used in the following description are a side where the first band part 31A is provided (left side of the paper surface in fig. 2A) and a side where the second band part 31B is provided (right side of the paper surface in fig. 2A), respectively.

The claw portion 32 is formed near one end portion in the longitudinal direction of the first belt portion 31A. In the present embodiment, the 3

claw portions

32a, 32b, and 32c are formed so as to be aligned in a line along the longitudinal direction of the belt main body 31. Of the 3 claw portions, the

claw portions

32a and 32b are formed by raising a part of the belt main body 31 (first belt portion 31A) on the surface 31A side, and the claw portion 32c located on the side closest to the longitudinal direction is formed by bending (cutting and raising) a part of the belt main body 31 on the surface 31A side.

The hole 33 is formed near the other end of the second band 31B in the longitudinal direction. In the present embodiment,

holes

33a, 33b, and 33c into which the

claw portions

32a, 32b, and 32c are respectively fitted when the ring body 30' shown in fig. 3 is formed are formed in a row along the longitudinal direction of the belt main body 31. The holes 33a to 33c are through holes that are open on the front surface 31a and the back surface 31b of the belt main body 31.

The projection 34 is formed between the claw portion 32 and the hole 33, and more specifically, is formed in a region on one side in the longitudinal direction of the hole 33 in the second band portion 31B. The protrusion 34 is formed in a Q-shape in side view by being composed of: a pair of

leg portions

34a, 34a provided apart in the longitudinal direction; and a top portion 34b connecting the top ends of the two leg portions 34 a. The distance between the one leg portion 34a and the other leg portion 34a is set in accordance with a fastening force to be applied to a fastening target (here, the large-diameter cylindrical portion 21 of the protective cover 20).

A bulge 35 is formed between the claw portion 32 and the protrusion 34. The bulging portion 35 is formed by forming two slits parallel to each other extending in the longitudinal direction of the belt main body 31 in the belt main body 31 and then bulging a portion between the two slits on the surface side 31 a. The slit is formed such that one end is located at one end in the longitudinal direction of the second band portion 31B and the other end is located within the range of the first band portion 31A. By forming the bulging portion 35 in this manner, a strip-shaped groove portion extending in the longitudinal direction of the belt main body 31 is defined on the rear surface side of the bulging portion 35. This groove portion functions as a housing groove 37 into which an insertion piece 36 formed at one end portion in the longitudinal direction of the belt main body 31 is inserted (housed) when the annular body 30' shown in fig. 3 is formed.

The protective cover tape 30 having the above-described structure is used in the following manner.

First, the band main body 31 is rolled up in the longitudinal direction thereof, and the claw portions 32a to 32c corresponding to the respective holes 33a to 33c are fitted to each other, whereby the band main body 31 is deformed into an annular form. As a result, as shown in fig. 3, an annular body 30' is formed in which the second band part 31B is superposed on the radially outer side of the first band part 31A. At this time, the insertion piece 36 formed at one end portion in the longitudinal direction of the belt body 31 is accommodated in the belt-like accommodation groove 37. Therefore, the fastening of the large-diameter cylindrical portion 21 of the protective cover 20 by caulking the protrusion 34 can be performed in a state where the insertion piece 36 is accommodated in the accommodation groove 37, that is, in a state where there is no step in the inner diameter surface of the annular body 30' which is a surface for fastening the large-diameter cylindrical portion 21 of the protective cover 20. This enables the large-diameter cylindrical portion 21 of the protective cover 20 to be fastened with high accuracy.

Next, the large-diameter cylindrical portion 21 of the protective cover 20 and the cup-shaped portion 6 of the outer joint member 2 to be attached are arranged to overlap with each other on the radially inner side of the annular body 30', and in this state, as shown in fig. 9, the protrusions 34 are caulked from both circumferential sides, whereby the protrusions 34 are plastically deformed so that the root portions 34c of one leg portion 34a and the root portions 34c of the other leg portion 34a approach each other. Accordingly, the circumferential 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 protective cover 20, and as a result, the large diameter cylindrical portion 21 is fixed to the outer diameter surface of the cup portion 6. After the projection 34 is caulked, the claw portions 32a to 32c and the corresponding hole portions 33a to 33c are engaged with each other in the circumferential direction of the annular body 30 ', and therefore, the expansion deformation of the annular body 30' is restricted.

The basic structure and the usage of the protective cover tape 30 according to the embodiment of the present invention are as described above, and the protective cover tape 30 has the following characteristic structure.

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

In this way, when the annular body 30' shown in fig. 3 is formed and then the projections 34 are caulked (see fig. 9), the required rigidity of the projections 34 can be ensured, and therefore the projections 34 can be prevented from being largely deformed to such an extent that the root portions 34c of the one leg portions 34a and the root portions 34c of the other leg portions 34a come into contact with each other as much as possible. Accordingly, since the projection 34 can be caulked with a predetermined caulking force, a required tightening force in the diameter reduction direction can be stably applied to the large-diameter cylindrical portion 21 of the boot 20.

When the annular body 30' shown in fig. 3 is formed by rolling up the band main body 31 and fitting the claw portions 32(32a to 32c) into the corresponding holes 33(33a to 33c), 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, as shown in fig. 5(a), which is an enlarged view of the portion B of fig. 3. At this time, for example, as shown in fig. 6, when a wide radial gap Gr having a maximum gap width t exceeding 0.5mm is formed between the both

belt portions

31A and 31B, the contact point P between the claw portion 32 (particularly 32c) and the second belt portion 31B is located on the tip end side of the claw portion 32 c. Therefore, when the projection 34 is caulked in this state, a large stress (in fig. 6, a stress along the circumferential direction of the ring body 30' indicated by black arrows, which may be referred to as a moment load) acts on the claw portion 32 (in particular, 32c) with the caulking, and the possibility of breakage or the like of the claw portion 32 (in particular, 32c) is increased.

On the other hand, the protective cover band 30 of the present embodiment shown in fig. 5A is configured such that the maximum gap width t of the radial gap Gr formed between the

band portions

31A and 31B at the time of forming the annular body 30' is 0.5mm or less (t 0.5mm) and more preferably 0.35mm or less (t 0.35 mm). As is clear from a comparison of fig. 5A and 6, the projection 34 can be caulked with the contact point between the claw portion 32c and the second band portion 31B being located on the root side of the claw portion 32 c. This makes it possible to prevent, as much as possible, breakage of the claw portion 32 and the like caused by a large stress applied to the claw portion 32 (particularly 32c) as the projection portion 34 is caulked. Therefore, a predetermined tightening force can be stably applied to the large-diameter cylindrical portion 21 of the protective cover 20.

In order to satisfy the relational expression of t ≦ 0.5mm (preferably t ≦ 0.35mm), in the present embodiment, it takes time to form the claw portion 32c positioned on the side closest to the longitudinal direction out of the 3 claw portions 32a to 32c formed in the first band portion 31A. Specifically, as shown in fig. 5C, the claw portion 32C is formed into a substantially L-shaped cross section (inverted L-shaped) provided with a bent portion 32d, and the bent portion 32d has a surface substantially parallel to the surface 31A, and satisfies the relational expression "h ≦ d +0.5 mm" when the separation distance (shortest separation distance) between the surface and the surface 31A of the first band portion 31A is h. Describing the shape of the claw portion 32c in more detail, the claw portion 32c is formed into a substantially L-shaped cross section by: a rising portion that forms an angle of approximately 90 ° with respect to the surface 31A of the first belt portion 31A; and a bent portion 32d formed by bending or bending a tip end of the rising portion, and forming an angle of approximately 90 ° with respect to the rising portion.

However, in the protective cover strap 30 of the present embodiment used in a state in which the hook portions 32 are fitted in the holes 33, the longitudinal dimension of each hole 33a to 33c needs to be set to be equal to or larger than the longitudinal dimension of the corresponding hook portion 32a to 32 c. However, when the longitudinal dimension of the hole is the same as the corresponding claw (when a circumferential gap is not formed between the corresponding claw and the hole when the annular body 30 'is formed as shown in fig. 8), the caulking operation of the protrusion 34 performed after the annular body 30' is formed cannot be appropriately performed, and there is a possibility that a predetermined fastening force cannot be applied to the large-diameter cylindrical portion 21 of the boot 20.

The reason why the caulking operation of the projection 34 may not be appropriately performed when the circumferential gap is not formed is as follows. First, in the structure of the cover tape 30, immediately after the caulking operation of the projection 34 is started, as shown in fig. 7, the second tape portion 31B is elastically deformed in a direction (radially outward) away from the first tape portion 31A, whereby the claw portions 32(32a, 32B in this case) are disengaged from the holes 33(33a, 33B in this case). As the caulking work of the projection 34 progresses (the amount of caulking increases), the second band part 31B is elastically deformed in a direction (radially inward) toward the first band part 31A, whereby the claw parts 32a, 32B are fitted into the corresponding hole parts 33a, 33B again, but as the caulking work of the projection 34 progresses, the circumferential relative position of the second band part 31B (the hole part 33 formed in the second band part 31B) with respect to the first band part 31A (the claw part 32 formed in the first band part 31A) changes, and therefore, when the longitudinal dimension of the hole part 33 is the same as the dimension of the corresponding claw part 32, it is difficult to fit the corresponding claw part 32 (here, 32a, 32B) into the hole part 33 (here, 33a, 33B) again.

The above-described problem can be solved by making the longitudinal dimension of the hole 33 larger than the longitudinal dimension of the corresponding claw 32 (increasing the gap width of the circumferential gap formed between the corresponding hole and the claw at the time of forming the annular body 30'). However, as the gap width of the circumferential gap becomes larger, the amount of relative movement between the first band part 31A and the second band part 31B caused by the caulking of the protrusion 34, or the circumferential load that loads the claw part 32 (particularly 32c) after the caulking of the protrusion 34 becomes larger, so that the possibility of breakage or the like of the claw part 32 (particularly 32c) is increased.

In the protective cover strap 30 of the present embodiment, the longitudinal dimensions of the hook portions 32a, 32B and the holes 33a, 33B are set so that, as shown in fig. 5B, when the annular body 30' is formed, circumferential gaps Gc are formed between the corresponding hook portions 32 (here, 32a, 32B) and the holes 33a, 33B, and the gap width of the circumferential gap Gc is w, the relational expression of 0 < w ≦ 0.8mm, more preferably 0.1mm ≦ w ≦ 0.6mm is satisfied. This makes it possible to smoothly fit the claw portions 32 into the corresponding holes 33 (the annular body 30' can be easily formed), and also makes it possible to effectively reduce the possibility of breakage and the like of the claw portions 32 (particularly 32c) when caulking the projecting portions 34, which is advantageous in that a predetermined tightening force is stably applied to the large-diameter cylindrical portion 21 of the boot 20.

In combination with the above operational effects, the protective cover band 30 according to the embodiment of the present invention has a feature that a predetermined tightening force can be stably applied to the large-diameter cylindrical portion 21 of the protective cover 20.

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

For example, in the above-described embodiment, the number of the claw portions 32 and the holes 33 is 3 in each direction along the longitudinal direction of the band main body 31 (the circumferential direction of the annular body 30'), but the number and arrangement of the claw portions 32 and the holes 33 can be arbitrarily set as long as the shape can be maintained when the band main body 31 is deformed into the annular shape.

In addition, although the case where the protective cover tape 30 according to the embodiment of the present invention is used when the protective cover 20 made of resin is fixed to an attachment object has been described above, the protective cover tape 30 may be used when a rubber protective cover is fixed to an attachment object.

In addition, although the present invention has been described above as being applied to a constant velocity universal joint constituting a drive shaft and a protective cover band for fixing a protective cover to a shaft member, the present invention may also be applied to a protective cover band for fixing a protective cover to a constant velocity universal joint constituting a drive shaft and a shaft member. The present invention is also applicable to a cover tape for fixing a cylindrical portion of a cover, which houses a screw shaft of a ball screw in an inner periphery thereof, to an attachment target in an electric actuator including the ball screw, for example.

Needless to say, the present invention is not limited to the above-described embodiments, and can be implemented in various ways without departing from the scope of the present invention.

Claims

1. A protective cover tape is provided with: a belt main body composed of a metal belt plate; a claw portion and a hole portion which are respectively arranged at the end portions of one side and the other side of the belt main body in the length direction; and a Q-shaped protrusion portion provided on the band main body and disposed between the claw portion and the hole portion in a side view,

wherein the protector band caulks the protrusion portion in a direction in which a circumferential length of an annular body formed by fitting the claw portion into the hole portion is reduced, thereby applying a tightening force in a diameter reduction direction to a cylindrical portion of an elastic sealing protector disposed radially inward of the annular body,

when the thickness of the metal strip plate is d and the thickness of the root portions of the pair of leg portions constituting the protrusion is d1, a relational expression of 0.8d < d1 < d is satisfied.

2. The protective cover strap of claim 1,

the belt main body is provided with: a first band having the claw portion; and a second band part having the hole and overlapping the first band part on the outside in the radial direction when the annular body is formed,

when the annular body is formed, a maximum gap width of a radial gap formed between an outer diameter surface of the first band part and an inner diameter surface of the second band part facing each other is t, and a relational expression that t is less than or equal to 0.5mm is satisfied.

3. The protective cover strap according to claim 1 or 2,

when the annular body is formed, a relational expression of 0 < w.ltoreq.0.8 mm is satisfied where w is a gap width of a circumferential gap formed between the claw portion and the hole portion.