Wire protector and manufacturing method of corrugated tube

Abstract

To provide an electric wire protector capable of more reliably fixing an electric wire housed therein.SOLUTION: A wire protector 1 includes: a corrugated tube 10 in which annular valleys 11 and peaks 12 are alternately formed along a longitudinal direction X, slits are provided along the longitudinal direction X so that an opening cross section is substantially C-shaped, and a first end edge part 10a and a second end edge part 10b divided by the slits overlap each other in a circumferential direction. A band body provided with the serration groove, and the binding band having a head part provided at one end of the band body and engaged with the serration groove when the band body is inserted from the other end side, the binding band being attached to an outer circumference of the corrugated tube, in which the band body is provided with the serration groove on an outer surface when the band body is attached to the outer circumference of the corrugated tube 10. The convex part capable of engaging with the valley part of the corrugated tube is provided on a surface opposite to the serration groove.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wire protector and a method for manufacturing a corrugated tube used in the wire protector. [Background technology]

[0002] BACKGROUND ART Conventionally, as a member for protecting the periphery of an electric wire, for example, a member in which protrusions are formed on the inner surface of a tube to prevent misalignment between the tube and the electric wire has been proposed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-69637 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a wire protector and a method for manufacturing a corrugated tube that can more reliably fix wires housed inside. [Means for solving the problem]

[0005] One aspect of the present disclosure is a wire protector comprising: a cylindrical corrugated tube in which annular valley portions and peak portions are alternately formed along the longitudinal direction, and slits are formed along the longitudinal direction so that the opening cross section is generally C-shaped, one end edge portion and the other end edge portion separated by the slits overlap each other in the circumferential direction, and at the overlapping portion of the one end edge portion and the other end edge portion, the valley portion of the one end edge overlaps the valley portion of the other end edge, and the peak portion of the one end edge overlaps the peak portion of the other end edge; and a band main body having serration grooves, and a cable tie attached to the outer periphery of the corrugated tube, the band main body having a head portion that is attached to one end of the band main body and engages with the serration grooves when the band main body is inserted from the other end side, the cable tie being attached to the outer periphery of the corrugated tube, the serration grooves being formed on the surface of the band main body that will be on the outer side when attached to the outer periphery of the corrugated tube, and the convex portion that can engage with the valley portion of the corrugated tube being provided on the surface opposite to the serration grooves. Another aspect of the present disclosure is a method for manufacturing a corrugated tube used in the above-mentioned wire protector, the method comprising the steps of: forming a cylindrical tube by extrusion molding; forming annular valley portions and peak portions alternately along the longitudinal direction on the outer peripheral surface of the tube to form a corrugated tube; providing slits along the longitudinal direction so that the opening cross section of the corrugated tube is substantially C-shaped; and radially compressing the corrugated tube with the slits provided therein so that one end edge portion and the other end edge portion separated by the slits overlap each other in the circumferential direction. [Effects of the Invention]

[0006] According to the wire protector and the method for manufacturing a corrugated tube according to the present invention, the wires housed inside can be more reliably fixed. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view of a wire protector 1 according to an embodiment. [Figure 2]2 is a cross-sectional view of a portion corresponding to region A of the corrugated tube 10 shown in FIG. [Figure 3] 1 is a schematic diagram showing a corrugated tube manufacturing apparatus 100. FIG. [Figure 4] 10(A) and 10(B) are diagrams illustrating the configuration of a binding band 20. FIG. [Figure 5] 1(A) to 1(C) are diagrams illustrating the configuration of each part of the binding band 20. FIG. [Figure 6] 1(A) to 1(C) are diagrams illustrating how the wire protector 1 is used. [Figure 7] 3A and 3B are diagrams illustrating an engagement state between the corrugated tube 10 and the binding band 20. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described. Note that the drawings attached to this specification are all schematic diagrams, and the shape, scale, aspect ratio, etc. of each part have been modified or exaggerated from the actual product for ease of understanding. Furthermore, hatching indicating cross sections of components has been omitted as appropriate in the drawings. In this specification, terms specifying shapes, geometric conditions, and the degree thereof, such as "parallel" and "direction," include not only the strict meaning of the terms but also the range of the degree to which they can be considered to be approximately parallel and the range of the range in which they can be considered to be roughly in that direction.

[0009] Fig. 1 is a perspective view of a wire protector 1 according to an embodiment. Fig. 2 is a cross-sectional view of a portion corresponding to region A of the corrugated tube 10 shown in Fig. 1. In the drawings illustrating the embodiment, the direction along the longitudinal direction of the corrugated tube 10 is referred to as the X direction (longitudinal direction X). In the embodiment, "direction" may also be referred to as "side" as appropriate.

[0010] As shown in FIG. 1 , the wire protector 1 of the embodiment includes a corrugated tube 10 and a cable tie 20. The corrugated tube 10 is a cylindrical member capable of storing electric wires therein. The corrugated tube 10 has annular valley portions 11 and peak portions 12 formed alternately along a longitudinal direction X. The corrugated tube 10 has slits (described later) formed along the longitudinal direction X so that an opening cross section perpendicular to the longitudinal direction X has a substantially C-shape. The corrugated tube 10 is divided by the slits into a first end edge portion (one end edge portion) 10a and a second end edge portion (the other end edge portion) 10b that overlap each other in the circumferential direction. The first end edge portion 10a is a portion located on the radially inner side of the corrugated tube 10. The second end edge portion 10b is a portion located on the radially outer side of the corrugated tube 10. The first end edge 10a and the second end edge 10b of the corrugated tube 10 are biased in the same radial direction. That is, the first end edge 10a and the second end edge 10b are biased toward the center in the radial direction. Therefore, as shown in Fig. 1, the portion where the first end edge 10a and the second end edge 10b of the corrugated tube 10 overlap each other in the circumferential direction remains closed unless opened by an operator.

[0011] As shown in Fig. 2, the corrugated tube 10 is configured so that the valleys 11a of the first edge 10a and the valleys 11b of the second edge 10b overlap, and the peaks 12a of the first edge 10a and the peaks 12a of the second edge 10b overlap. In Fig. 2, the valleys 11 at the same position in the longitudinal direction X are shown as valleys 11a and 11b at the overlapping positions. Similarly, the peaks 12 at the same position in the longitudinal direction X are shown as peaks 12a and 12b at the overlapping positions.

[0012] In Figure 2, if the width W1 of the overlapping valley portions 11a and 11b and the width W2 of the peak portions 12a and 12b are the same, they will not actually overlap without a gap as shown in Figure 2, but will instead have a gap between them. However, if the corrugated tube 10 is made of a flexible material, the entire tube will stretch in the longitudinal direction X, resulting in a state as shown in Figure 2 or a state close to that shown in Figure 2. Alternatively, by making the width W1 of the valley portion 11a located on the inside in the radial direction narrower than the width W1 of the valley portion 11b located on the outside in the radial direction and making the width W2 of the peak portion 12a located on the inside in the radial direction narrower than the width W2 of the peak portion 12a located on the outside in the radial direction, it is also possible to configure the two so that they overlap without a gap, as shown in Figure 2.

[0013] Examples of materials for forming the corrugated tube 10 include resins such as polypropylene, polyamide, and polyethylene. The inner diameter of the corrugated tube 10 is, for example, about 10 to 70 mm. The wall thickness of the corrugated tube 10 is, for example, about 0.4 to 0.7 mm.

[0014] Next, a manufacturing apparatus for the corrugated tube 10 and a manufacturing method for the corrugated tube 10 using this manufacturing apparatus will be described. 3 is a schematic diagram showing a corrugated tube manufacturing apparatus 100. In FIG. 3, the movement direction of the corrugated tube 10 during the manufacturing process is designated as the X0 (X01-X02) direction to distinguish it from the longitudinal direction X of the corrugated tube 10. Note that in FIG. 3, the movement direction X0 of the corrugated tube 10 coincides with the longitudinal direction X of the corrugated tube 10 shown in FIG.

[0015] As shown in Fig. 3, the corrugated tube manufacturing apparatus 100 includes an extrusion molding machine 110, a blow molding machine 120, a slit forming machine 130, and a diameter reducing machine 140. In Fig. 3, a tube take-up device, a heater (heating device), etc. are omitted as appropriate.

[0016] The extrusion molding machine 110 is a device that uses extrusion molding to form a cylindrical tube 10s that is the base of the corrugated tube 10. In the extrusion molding machine 110, a resin material heated by a heater is sent out to the outlet side by a screw cylinder (neither of which is shown), and the material is passed through a die 111 that serves as an extrusion opening, thereby obtaining the cylindrical tube 10s. The cylindrical tube 10s sent out from the extrusion molding machine 110 does not have annular valley portions 11 and peak portions 12 formed thereon.

[0017] The blow molding machine 120 is a device that alternately forms annular valley portions 11 and peak portions 12 (see FIG. 1) along the longitudinal direction X on the side surface of the tube 10s delivered from the extruder 110. The blow molding machine 120 includes a pair of mold movement mechanisms 120a and 120b. Since the mold movement mechanisms 120a and 120b have substantially the same configuration, the configuration of the mold movement mechanism 120a will be described below as an example. The mold movement mechanism 120a includes multiple molds 121, an endless belt 122, and a pair of rollers 123 and 124. The mold 121 is a member for forming the valley portions 11 and peak portions 12 of the corrugated tube 10. The multiple molds 121 are arranged at equal intervals along the extension direction of the endless belt 122.

[0018] The endless belt 122 is wound around a pair of rollers 123 and 124. The pair of rollers 123 and 124 are driven by a motor, a gear mechanism, etc. (not shown) so as to move the mold 121 from the X02 side to the X01 side. That is, the pair of rollers 123 and 124 of the mold moving mechanism 120a are driven to rotate counterclockwise in the arrangement shown in Fig. 3. Also, the pair of rollers 123 and 124 of the mold moving mechanism 120b are driven to rotate clockwise in the arrangement shown in Fig. 3.

[0019] By sandwiching the tube 10s between a pair of mold movement mechanisms 120a, 120b of the blow molding machine 120 and sending it out in the X01 direction, and supplying compressed air from inside the tube 10s, a corrugated tube 10 can be produced in which annular valley portions 11 and peak portions 12 are formed alternately along the longitudinal direction X (see Figure 1).

[0020] The slit forming machine 130 is a device that forms a slit S along the longitudinal direction X of the tube 10s. In the slit forming machine 130, cutting edges of cutting teeth (not shown) are aligned parallel to the longitudinal direction X to make incisions in the side surface of the tube 10s, thereby obtaining a corrugated tube 10 with a slit S formed therein. By forming the slit S along the longitudinal direction X of the corrugated tube 10 by the slit forming machine 130, the opening cross section of the corrugated tube 10 becomes substantially C-shaped. With the slit S formed in the corrugated tube 10, the first end edge portion 10a and the second end edge portion 10b of the corrugated tube 10 face each other with the slit S sandwiched therebetween.

[0021] The diameter reducing machine 140 is a device that radially reduces the corrugated tube 10 having the slit S formed therein. The diameter reducing machine 140 includes a throat-shaped die 141 and a heater 142. In the diameter reducing machine 140, the corrugated tube 10 having the slit S formed therein is fed into the die 141 heated by the heater 142, thereby producing the corrugated tube 10 (see FIG. 1 ) in which the first end edge portion 10a and the second end edge portion 10b separated by the slit S overlap each other in the circumferential direction.

[0022] Next, a description will be given of the configuration of the binding band 20. The binding band 20 is a member that fixes the corrugated tube 10. 4(A) and (B) are diagrams illustrating the configuration of the cable tie 20. Fig. 4(A) is a diagram of the cable tie 20 as viewed from the front side. Fig. 4(B) is a side view of the cable tie 20. In Fig. 4 and Fig. 5 (described later), the direction along the longitudinal direction of the cable tie 20 is referred to as the x (x1-x2) direction, and the direction perpendicular to the x direction on the paper is referred to as the y (y1-y2) direction, in order to distinguish it from the longitudinal direction X (X direction) of the corrugated tube 10.

[0023] Figures 5(A) to 5(C) are diagrams illustrating the configuration of each part of the binding band 20. Figure 5(A) is a cross-sectional view corresponding to the s1-s1 cross-section of Figure 4(A). Figure 5(B) is a cross-sectional view corresponding to the s2-s2 cross-section of Figure 4(A). Figure 5(C) is a cross-sectional view corresponding to the s3-s3 cross-section of Figure 4(A). Note that in Figures 5(A) to 5(C), the scale, aspect ratio, etc. of the drawings have been appropriately changed from Figures 4(A) and (B).

[0024] 4(A) and 4(B), the cable tie 20 includes a head portion 21, a band portion (band main body) 22, and a tail portion 23. The cable tie 20 including the head portion 21, the band portion 22, and the tail portion 23 is molded, for example, as an integrated part. Examples of materials that can be used to form the cable tie 20 include resins such as polypropylene and polyamide.

[0025] The head portion 21 is a portion that engages with serration grooves 220 (described later) of the band portion 22 to secure the band portion 22 to the corrugated tube 10. The head portion 21 is configured in a box frame shape, and as shown in FIG. 5(A), a through hole 210 is formed along the x direction. A locking claw 211 is provided inside the through hole 210. A saw-like protrusion 212 that can engage with the serration grooves 220 of the band portion 22 is provided on the y1-side surface of the locking claw 211. An end 213 on the x2 side of the locking claw 211 is integrated with the y2-side of the head portion 21. That is, the locking claw 211 is supported inside the through hole 210 so as to be swingable in the y1 and y2 directions. Furthermore, because the locking claw 211 protrudes toward the y1 side, when pressed toward the y2 side, a repulsive force is generated toward the y1 side. In other words, the locking claw 211 is biased toward the y1 side.

[0026] The band portion 22 is a portion that is attached to the outer periphery of the corrugated tube 10. An end (one end) of the band portion 22 on the x2 side is formed integrally with the head portion 21 (described later). On the other hand, a tail portion 23 is formed on the x1 side of the band portion 22. The tail portion 23 is a portion that is inserted into the through hole 210 of the head portion 21, and is molded integrally with the band portion 22. The tail portion 23 is formed in a tapered shape that narrows toward the x1 side to facilitate insertion into the through hole 210. Note that the cable tie 20 may be configured without the tail portion 23.

[0027] As shown in Fig. 4(A), the band portion 22 has serration grooves 220 on the surface (y2 side surface) that becomes the outer side when attached to the outer peripheral surface of the corrugated tube 10. As shown in Fig. 5(B), the serration grooves 220 are saw-tooth grooves configured to be able to engage with the locking claws 211 of the head portion 21. The serration grooves 220 are formed along the x direction, which is the longitudinal direction of the band portion 22.

[0028] As shown in FIG. 4(B) and other figures, the band portion 22 has a protrusion 221 on the surface opposite to the serration groove 220 (the surface on the y1 side). The protrusion 221 is a portion that can engage with the valley portion 11 of the corrugated tube 10. The protrusion 221 is formed along the x direction, which is the longitudinal direction of the binding band 20.

[0029] As shown in FIG. 5(C), the width W3 of the convex portions 221 is set to be the same as or slightly shorter than the width W1 (see FIG. 2) of the valley portions 11 of the corrugated tube 10. The width W4 of the band portion 22 is set to be approximately the sum of the width W3 of the convex portions 221 and the width W1 of the valley portions 11 of the corrugated tube 10. The width W4 of the band portion 22 may be long enough so that the band portion 22 does not fall off the peak portions 12 when the convex portions 221 are engaged with the valley portions 11 of the corrugated tube 10. The engagement between the convex portions 221 of the band portion 22 and the valley portions 11 of the corrugated tube 10 will be described later.

[0030] Next, usage of the wire protector 1 configured as above will be described. 6(A) to 6(C) are diagrams illustrating how the wire protector 1 is used. FIG. 7 is a diagram illustrating the state in which the corrugated tube 10 and the binding band 20 are engaged with each other.

[0031] First, as shown in FIG. 6(A), an operator opens the portion of the corrugated tube 10 where the first end edge 10a and the second end edge 10b overlap, and stores an electric wire W inside. After storing the electric wire W inside the corrugated tube 10, the operator closes the first end edge 10a and the second end edge 10b, so that the first end edge 10a and the second end edge 10b of the corrugated tube 10 overlap each other (see FIG. 1). As a result, in the corrugated tube 10, the valleys 11a of the first end edge 10a and the valleys 11b of the second end edge 10b overlap each other, and the peaks 12a of the first end edge 10a and the peaks 12a of the second end edge 10b overlap each other (see FIG. 2).

[0032] Next, as shown in Fig. 6(B), the worker wraps the band portion 22 of the binding band 20 around the outer peripheral surface of the corrugated tube 10 and inserts the tail portion 23 into the through-hole 210 of the head portion 21. At this time, as shown in Fig. 7, the convex portion 221 of the band portion 22 engages with the valley portion 11 of the corrugated tube 10.

[0033] The tail portion 23 of the cable tie 20 can be retracted by inserting it into the through-hole 210 of the head portion 21 and protruding it from the opposite side of the insertion direction. The operator can retract the band portion 22 connected to the tail portion 23 by retracting the protruding tail portion 23 from the head portion 21. When the band portion 22 is retracted from the head portion 21, the locking claws 24 of the head portion 21 are pushed up toward the y2 side (see FIG. 5A) opposite the biasing direction y1 by the serration grooves 220 of the band portion 22, preventing them from engaging with each other. Therefore, while the band portion 22 is being pulled in the x1 direction (see FIG. 5A), the serration grooves 220 of the band portion 22 and the protrusions 241 of the locking claws 24 do not engage with each other in the locking direction. The operator continues to pull the band portion 22 in this state until a predetermined tension (tightening force) is applied to the band portion 22, and stops pulling.

[0034] When the operator pulls the band portion 22 in the x1 direction and stops pulling at a position where a predetermined tension is applied, the band portion 22 moves slightly back toward the x2 side (see FIG. 5(A)). At this time, the serration grooves 220 of the band portion 22 and the protrusions 241 of the locking claws 24 engage with each other in a locking direction, so movement of the band portion 22 in the x2 direction is restricted from the position where the serration grooves 220 and the protrusions 241 engage with each other.

[0035] As a result, as shown in Fig. 6(C), the cable tie 20 can fix the outer peripheral surface of the corrugated tube 10 containing the electric wires W by tightening it mainly with the band portion 22. Note that Fig. 6(C) shows an example in which one cable tie 20 is attached to the outer peripheral surface of the corrugated tube 10, but a plurality of cable ties 20 may be attached along the longitudinal direction X of the corrugated tube 10.

[0036] According to the wire protector 1 of the present embodiment described above, the wires W housed inside the corrugated tube 10 can be reliably fixed by the binding band 20. As shown in Fig. 6(A), the corrugated tube 10 of this embodiment can easily accommodate an electric wire W inside by opening the overlapping portion of the first edge 10a and the second edge 10b. Furthermore, as shown in Fig. 2, the corrugated tube 10 has the valleys 11a of the first edge 10a and the valleys 11b of the second edge 10b overlapping with each other, and the peaks 12a of the first edge 10a and the peaks 12a of the second edge 10b overlapping with each other, thereby preventing internal contamination due to wind and rain and deterioration of the electric wire W due to ultraviolet rays and the like. Furthermore, as described above, misalignment of the overlapping portions in the longitudinal direction X can be prevented.

[0037] 7, when the cable tie 20 of this embodiment is attached to the outer peripheral surface of the corrugated tube 10, the convex portions 221 of the band portion 22 engage with the valley portions 11 of the corrugated tube 10, thereby preventing the cable tie 20 from shifting in the longitudinal direction X of the corrugated tube 10. Furthermore, the convex portions 221 of the cable tie 20 protrude from the surface opposite the serration grooves 220 of the cable tie 20, thereby reducing the protrusion of the band portion 22 when the cable tie 20 is attached to the outer peripheral surface of the corrugated tube 10.

[0038] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications and variations, such as the modified embodiments described below, are possible, and these are also included within the technical scope of the present disclosure. Furthermore, the effects described in the embodiments are merely a list of the most preferable effects resulting from the present disclosure, and are not limited to those described in the embodiments. The above-described embodiments and the modified embodiments described below can also be used in appropriate combinations, but detailed description thereof will be omitted.

[0039] (Variations) In the embodiment, an example has been described in which the width W1 of the valley portions 11 and the width W2 of the peak portions 12 (see FIG. 2) are the same in the corrugated tube 10, but this is not limiting. In the corrugated tube 10, the width W1 of the valley portions 11 and the width W2 of the peak portions 12 may be different widths. For example, the width W1 of the valley portions 11 may be wider than the width W2 of the peak portions 12.

[0040] In the embodiment, an example has been shown in which the slits S are formed along the longitudinal direction X of the tube 10s by a slit forming machine 130 equipped with cutting teeth (not shown) in the corrugated tube manufacturing apparatus 100 (see FIG. 3), but the present invention is not limited to this. For example, the slits S may be formed in the blow molding machine 120 when the annular valley portions 11 and peak portions 12 are formed in the tube 10s.

[0041] In the embodiment, the corrugated tube manufacturing apparatus 100 (see FIG. 3 ) is configured to radially shrink the corrugated tube 10 using a diameter reducing machine 140 equipped with a throat-shaped die 141, but the configuration is not limited thereto. For example, the diameter reducing machine 140 may be a mechanism that mechanically presses the corrugated tube 10 in the radial direction. In other words, the mechanism for radially shrinking the corrugated tube 10 in the corrugated tube manufacturing apparatus 100 may have any configuration. [Explanation of symbols]

[0042] 1: Wire protector 10: Corrugated tube 11: Valley 12: Yamabe 10a: First edge (one edge) 10b: Second edge (other edge) 20: Cable ties 21: Head 22: Band part (band body) 23: Tail section 100: Corrugated tube manufacturing equipment 110: Extrusion molding machine 110 120: Blow molding machine 120 130: Slit forming machine 140: Diameter reducing machine 220: Serration groove 221: Convex

Claims

1. a cylindrical corrugated tube in which annular valleys and peaks are alternately formed along the longitudinal direction, and in which slits are provided along the longitudinal direction so that the opening cross section is substantially C-shaped, and one end edge and the other end edge separated by the slits overlap each other in the circumferential direction, and in the overlapping portion of the one end edge and the other end edge, the valleys of the one end edge and the valleys of the other end edge overlap, and the peaks of the one end edge and the peaks of the other end edge overlap; a binding band having a band body with serration grooves and a head portion provided at one end of the band body and engaging with the serration grooves when the band body is inserted from the other end side, the binding band being attached to the outer periphery of the corrugated tube; Equipped with The band body has serration grooves on the surface that becomes the outer side when attached to the outer periphery of the corrugated tube, and a convex portion that can engage with the valley portion of the corrugated tube on the surface opposite the serration groove.

2. A method for manufacturing a corrugated tube used in the wire protector according to claim 1, comprising: forming a cylindrical tube by extrusion; forming annular valleys and peaks alternately along a longitudinal direction on an outer peripheral surface of the tube to form a corrugated tube; providing a slit along the longitudinal direction of the corrugated tube so that the opening cross section of the corrugated tube is substantially C-shaped; a step of radially contracting the corrugated tube having the slits formed therein so that one end edge portion and the other end edge portion separated by the slits overlap each other in the circumferential direction; A method for manufacturing a corrugated tube comprising:

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