Patent Description:
Conventionally, for the purpose of identifying a cable such as an optical fiber cable and an electrical wire cable, a tube with characters, figures, symbols or colors or the like printed on an outer peripheral surface is prepared, and a cable is inserted into the tube to attach the tube to the cable. Thereby, it is possible to identify the cable and prevent erroneous wiring or the like.

However, there is a problem that it is difficult to insert the cable into the tube when the outer diameter of the cable is too large for the inner diameter of the tube, while the tube is not sufficiently fixed to the cable and is liable to rotate or slip off when the outer diameter of the cable is too small for the inner diameter of the tube.

In order to solve such a problem, PTL <NUM> discloses a tube in which a contact piece that bends and comes into contact with a cable when pressed is provided to protrude from an inner wall surface.

PTL <NUM> discloses a tube in which a plurality of ribs protruding from an inner wall surface toward the center are provided in order to enable reliable fixing even when the outer diameter of a cable varies.

PTL <NUM> discloses a tube in which a plurality of ribs parallel to each other are provided to protrude from an inner wall surface.

However, when only one protrusion such as a contact piece or a rib protruding from an inner wall surface is provided, the problem that the tube easily rotates or slips off cannot be solved because the tube is not held in the cable with a sufficient force.

On the other hand, in the case of a conventional tube having a plurality of protrusions provided on an inner wall surface, the holding force for the cable is improved as compared to the case where only one protrusion is provided, but printing omissions such as rubbing and misalignment of characters and the like and white streaks may occur when printing characters and the like on an outer peripheral surface of the tube. That is, when printing characters and the like on an outer peripheral surface of the tube, the tube is crushed by being sandwiched between a platen roller and a thermal head. However, since a plurality of protrusions are provided on an inner wall surface of the tube, the tube is not crushed flat (becomes uneven) depending on the crushing direction, and some parts where the thermal head is difficult to contact may occur, and the printing may not be performed well.

<CIT> relates to a label clip assembly comprising an annular clip having a plurality of projections extending radially from an inner surface of the clip towards a primary axis. <CIT>, <CIT>, <CIT> and <CIT> show further examples of tubes.

Therefore, an object of the present invention is to provide a tube having a holding force and being easily crushed.

The present invention is defined in independent claim <NUM>.

The following embodiments are merely examples for explaining the present invention, and the present invention should not be construed as being limited to the embodiments.

First, an example of a printer capable of printing characters, figures, colors or symbols and the like (hereinafter, referred to as the "characters and the like") on an outer peripheral surface of a tube according to the present embodiment will be described.

<FIG> is a perspective view of such a printer <NUM>.

The printer <NUM> includes a housing <NUM> in which a display unit <NUM> and an operation unit <NUM> are provided. A tube can be set as a print medium inside the housing <NUM>. Note that, as another print medium, a tape and other long medium may be selectively set inside the housing <NUM>.

The display unit <NUM> includes a display screen such as a liquid crystal display, and displays characters and the like input by the operation unit <NUM>. The operation unit <NUM> is composed of a keyboard having a plurality of operation buttons. The operation unit <NUM> inputs characters, numbers and codes onto the print medium and performs various operations of the printer <NUM>.

The housing <NUM> is further provided with a lid <NUM> that opens and closes when an ink ribbon cassette <NUM> and the print medium are attached. Note that <FIG> shows a state in which the lid <NUM> is opened.

The printer <NUM> includes, as a printing mechanism for printing on the print medium, a cassette holder <NUM> in which a print medium such as a tube is selectively set, and a ribbon holder <NUM> in which the ink ribbon cassette <NUM> is set. The cassette holder <NUM> and the ribbon holder <NUM> may be integrally molded products made of resin or the like. The cassette holder <NUM> is configured so that a guide attachment for guiding the tube to a desired position can be installed when the print medium is a tube having a predetermined inner diameter or less.

The printer <NUM> further includes a platen roller <NUM> that conveys a long print medium such as a tube set in the cassette holder <NUM> or a tape released from a tape cassette, and a thermal head <NUM> that prints on a print medium such as a tube conveyed by the platen roller <NUM>.

The platen roller <NUM> conveys a print medium such as a tube by being rotated by a motor (not shown). The ink ribbon of the ink ribbon cassette <NUM> is configured to be fed in synchronization with the platen roller <NUM> by using the same motor. A print medium such as a tube conveyed by the platen roller <NUM> is arranged in a gap between the platen roller <NUM> and the ink ribbon.

The printer <NUM> includes a head moving mechanism <NUM> for performing an operation of moving the thermal head <NUM> in a direction approaching the platen roller <NUM> and an operation of moving the thermal head <NUM> in a direction away from the platen roller <NUM>. When the thermal head <NUM> moves in the direction approaching the platen roller <NUM> by the head moving mechanism <NUM> and presses the platen roller <NUM>, the print medium such as the ink ribbon and the tube is sandwiched between the thermal head <NUM> and the platen roller <NUM>, and the ink of the ink ribbon is transferred to the outer peripheral surface and the like of the tube by the heat of the thermal head <NUM>. In this way, it becomes possible to print the ink on the outer peripheral surface and the like of the tube. At this time, since the tubular tube is crushed flat, the ink can be suitably transferred to the outer peripheral surface and the like. By performing the approaching operation and the separating operation in this way, it becomes possible to print desired characters and the like on the outer peripheral surface and the like of the tube.

The printer <NUM> may further include a tube warmer <NUM> that warms the tube in order to prevent the printing onto the tube from rubbing. Further, a half-cut mechanism (not shown) for half-cutting a print medium such as a tube may be provided on the downstream side of the thermal head <NUM>. The tube, which was temporarily crushed flat at the time of printing, is elastically restored to a tubular shape, and is sent out from the printer in a state of being printed on the outer peripheral surface. When the tube is half-cut and has a cut, the tube can be easily cut into a tube of the desired length. By inserting a cable such as an optical fiber cable, an electric wire or other insert into such a tube and inserting it through the tube, it becomes possible to distinguish it from other inserts.

The configuration of the tube in which printing can be performed on the outer peripheral surface by such a printer <NUM> will be described. Note that the tube may be printed with character information or the like by a printer having a configuration other than the printer <NUM>.

Hereinafter, a tube <NUM> according to the first embodiment will be described. <FIG> is a sectional view of the tube <NUM> in which a cable CA (an example of the "insert") is inserted, taken along a direction perpendicular to an extending direction of the tube <NUM>, and <FIG> is a perspective view of the tube <NUM> in a state where the cable CA is not inserted. <FIG> is a sectional view showing the tube <NUM> in the above state, taken along the direction perpendicular to the extending direction of the tube <NUM>.

Note that the insert may be an optical fiber cable, an electric wire cable, an electric wire, or any other long object. Character information and the like are printed as identification information on the outer peripheral surface of the tube <NUM> during use. Therefore, by inserting these inserts through the tube <NUM>, it becomes possible to distinguish them from other inserts.

As shown in <FIG> and <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and three protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 12A of the body portion <NUM>, that is, a first protrusion 14A, a second protrusion 14B, and a third protrusion 14C (hereinafter, the first protrusion 14A, the second protrusion 14B, and the third protrusion 14C are collectively referred to as the "protrusions <NUM>"). Since the tube <NUM> is made of a synthetic resin such as polyvinyl chloride, both the body portion <NUM> and the protrusion <NUM> have flexibility.

The body portion <NUM> in the present embodiment is formed in a cylindrical shape with a central axis AX (<FIG>) as an axis. Therefore, in the cross section perpendicular to the extending direction of the tube <NUM>, the body portion <NUM> has an annular shape, and the inner wall surface 12A and an outer peripheral surface 12B each have a circular shape (<FIG>).

The three protrusions <NUM> in the present embodiment are provided to protrude from the inner wall surface 12A of the body portion <NUM>.

The first protrusion 14A includes a leading end portion 14A1 for contacting the outer peripheral surface of the cable CA in a state where the cable CA is inserted, and a base end portion 14A2 for connecting the leading end portion 14A1 and the inner wall surface 12A of the body portion <NUM>. Further, the first protrusion 14A is provided to extend in an axial direction substantially parallel to the central axis AX of the body portion <NUM>.

The first protrusion 14A is provided to be inclined toward a first portion 12A1 of the inner wall surface 12A connecting the first protrusion 14A and the second protrusion 14B so that it has an angle θ1 with respect to a straight line L1 connecting a center C1 of the body portion <NUM> and the inner wall surface 12A (connecting portion between the base end portion 14A2 of the first protrusion 14A and the inner wall surface 12A). Further, the first protrusion 14A according to the present embodiment is provided to be curved in an arc shape gradually separated from the inner wall surface 12A from the base end portion 14A2 to the leading end portion 14A1. Therefore, the distance between the first protrusion 14A and the first portion 12A1 is the largest at the tip of the leading end portion 14A1.

Similarly, in the cross sections of <FIG> and <FIG>, the leading end portion 14A1 of the first protrusion 14A is provided to have a thickness of at least a predetermined thickness (an example of the "first thickness") or more, and the base end portion 14A2 is provided to include at least a thin-walled portion (sometimes referred to as the "weakened portion") having a thickness smaller than this predetermined thickness. Therefore, when a force in an outer diameter direction acts on the leading end portion 14A1, the base end portion 14A2 is easily deformed in the outer diameter direction.

The thickness of the leading end portion (the "first thickness") is greater than a thickness of the base end portion. The thickness of the leading end portion (the "first thickness") is greater than a thickness of the weakened portion.

A length from the inner wall surface to the weakened portion may be shorter than a length from the weakened portion to the leading end portion.

In the present embodiment, the second protrusion 14B and the third protrusion 14C are provided in a rotational symmetry of <NUM> degrees with respect to the first protrusion 14A with reference to the center C1 of the body portion <NUM>. That is, the second protrusion 14B has a leading end portion 14B1 and a base end portion 14B2, and is provided to be inclined toward a second portion 12A2 of the inner wall surface 12A connecting the second protrusion 14B and the third protrusion 14C. The third protrusion 14C has a leading end portion 14C1 and a base end portion 14C2, and is provided to be inclined toward a third portion 12A3 of the inner wall surface 12A connecting the third protrusion 14C and the first protrusion 14A. Since the second protrusion 14B and the third protrusion 14C have the same configuration as the first protrusion 14A, detailed description thereof will be omitted. Note that the center C1 (<FIG>) of the body portion <NUM> in the cross section exists on the central axis AX (<FIG>) of the body portion <NUM>.

As a result of such a configuration, the first protrusion 14A, the second protrusion 14B, and the third protrusion 14C are provided non-parallel to each other to form an angle of approximately <NUM> degrees to each other in the cross section and are provided to be inclined in the same direction along a circumferential direction.

By providing the configuration in which the three protrusions <NUM> are provided in a rotational symmetry of <NUM> degrees in this manner, the cable CA can be supported from three directions by each of the three leading end portions 14A1 to 14C1 when the cable CA is inserted through the tube <NUM>. As shown in <FIG>, the leading end portions 14A1 to 14C1 of the respective protrusions <NUM> are deformed to the outer diameter side by the insertion of the cable CA and press the cable CA from the three directions toward the center C1, respectively. As a result, the tube <NUM> can exert a large holding force for the cable CA. However, as will be described later, only two protrusions <NUM> may be provided, or four or more protrusions <NUM> may be provided. Further, the protrusions <NUM> do not necessarily have to be provided in rotational symmetry.

Further, since each of the base end portions 14A2 to 14C2 of the protrusions <NUM> has a thin-walled portion having a thickness smaller than the thickness of each of the leading end portions 14A1 to 14C1, each base end portion is easily deformed when the cable CA is inserted into the tube <NUM>. Therefore, the cable CA can be easily inserted into the tube <NUM>. Further, since the protrusions <NUM> are provided in an arc shape gradually separated from the inner wall surface 12A from the base end portions 14A2 to 14C2 to the leading end portions 14A1 to 14C1, the cable CA typically comes into contact with the regions near the leading end portions 14A1 to 14C1 closer to the center C1 when the cable CA is inserted into the tube <NUM>. As a result, a large moment is applied to each of the base end portions 14A2 to 14C2, so that the base end portions 14A2 to 14C2 can be easily deformed. This also facilitates the insertion of the cable CA into the tube <NUM>. In addition, since the protrusions <NUM> are inclined in the same direction along the circumferential direction, it is also possible to prevent the protrusions <NUM> from interfering with the insertion of the cable CA into the tube <NUM>.

Furthermore, since the tube <NUM> has a structure that is easily crushed from any direction, it is possible to suitably print on the outer peripheral surface 12B at the time of printing. Hereinafter, the effect of the tube <NUM> according to the present embodiment, which is easily crushed from any direction, will be described.

The inventors of the present application have found that it is necessary to provide two or more protrusions on the tube in order to exert a large holding force for the cable CA, while the print quality on the outer peripheral surface of the tube may deteriorate and printing omissions may occur depending on the structure of the protrusions when two or more protrusions are provided. As a result of further studies, the inventors have found that the protrusions may hinder the tube from being crushed depending on the direction in which the tube is set when the tube is sandwiched between a platen roller and a thermal head and the like for printing. For example, assuming that two parallel protrusions are provided to face each other toward the center of the tube, when a force parallel to the protruding direction of the protrusions is applied to crush the tube, it is difficult to crush the tube flat because the protrusions protruding in the same direction hinder the tube from being crushed. Further, even when the tube can be crushed, one protrusion may be bent many times, and as a result, the outer peripheral surface of the tube when completely crushed may be greatly undulated and not flat. In such a case, since it becomes difficult to suitably press the ink ribbon pressed by the thermal head against the outer peripheral surface of the tube, the print quality deteriorates. On the other hand, when a force perpendicular to the protruding direction of the protrusions is applied to crush the tube, the protrusions do not hinder the crushing of the tube, so that the tube can be easily crushed. However, since a user does not always set the tube in the printer <NUM> in a direction in which the tube is easily crushed, in some cases, the protrusions may hinder the tube from being crushed, and further, suitable printing may be difficult.

On the other hand, although the tube <NUM> according to the present embodiment includes as many as three protrusions <NUM>, the deviation in the crushing difficulty depending on the direction is small as compared with the tube according to the above-described prior art. <FIG> are schematic views showing a process in which the tube <NUM> is crushed. <FIG> shows a state before the tube <NUM> is crushed, <FIG> shows a state in which the tube <NUM> is crushed, and <FIG> shows a state in the middle of being crushed. As shown in <FIG>, the plurality of protrusions <NUM> of the tube <NUM> are provided to be inclined in a direction approaching the inner wall surface 12A without going to the center C1 of the body portion <NUM>. Therefore, any straight line passing through the center C1 of the body portion <NUM> does not completely coincide with the extending directions of the protrusions <NUM>. Therefore, the deviation in the crushing difficulty depending on the direction is small, and the protrusions <NUM> do not significantly hinder the tube <NUM> from being crushed.

Further, the protrusions <NUM> are provided non-parallel to each other. Therefore, the extending directions of the plurality of protrusions are almost the same, so that it is possible to suppress the harmful effect of the plurality of protrusions hindering the tube from being crushed when the tube is crushed in that direction. This configuration also makes it possible to reduce the deviation in the crushing difficulty depending on the direction.

In addition, the protrusions <NUM> are inclined in the same direction along the circumferential direction. Therefore, unlike the prior art, it is possible to suppress a problem that one protrusion is bent many times, and as a result, the outer peripheral surface 12B when completely crushed is greatly undulated and not flat.

Hereinafter, a suitable numerical range in the configuration of the protrusions <NUM> of the tube <NUM> will be described. By prototyping and experimenting with protrusions of various shapes, the inventors of the present application have concluded that each numerical range described below is suitable.

First, the length of the protrusions <NUM> is preferably <NUM>% or less of the inner diameter of the inner wall surface 12A, respectively. In the state of <FIG> before being crushed, the distance from the base end portion 14A2 of the first protrusion 14Ato the base end portion 14B2 of the second protrusion 14B, which is apart from the base end portion 14A2 by approximately <NUM> degrees, is about <NUM>% of the inner diameter (the half value of the square root of <NUM> obtained from the base of an isosceles triangle whose apices are the center C1, the base end portion 14A2 and the base end portion 14B2 and in which the radius of the inner diameter of the inner wall surface 12A is two sides of equal length). If the length of the protrusions is set to about <NUM>% of the inner diameter, the protrusion may come into contact with the adjacent protrusion depending on the manufacturing error even in the state before being crushed, and the protrusion may collide with the adjacent protrusion in the middle of being crushed. When the protrusion collides with the adjacent protrusion in the middle of being crushed, the crushing of the tube may be hindered. Further, when the protrusion is bent due to collision with the adjacent protrusion, the protrusion may be bent many times, and as a result, the outer peripheral surface when crushed may not be flat, and it may be difficult to appropriately perform printing. However, when the length of the protrusion <NUM> is set to <NUM>% or less of the inner diameter, the occurrence of the problem as described above can be suppressed.

On the other hand, the length of the protrusions <NUM> is preferably <NUM>% or more of the inner diameter of the inner wall surface 12A, respectively. When the length of the protrusions <NUM> is set to <NUM>%, and the outer diameter of the cable CA is half the inner diameter of the inner wall surface 12A, three sides of a triangle where the position of the base end portion 14A2 of the first protrusion 14A contacting with the inner wall surface 12A is one apex (hereinafter, referred to as the "apex A"), the position near the tip of the leading end portion 14A1 contacting with the cable CA is one apex (hereinafter, referred to as the "apex B"), and the center C1 is one apex (hereinafter, referred to as the "apex C") are respectively defined such that the length between the apex A and the apex B is <NUM>% of the inner diameter of the inner wall surface 12A, the length between the apex B and the apex C is <NUM>% thereof, and the length between the apex C and the apex A is <NUM>% thereof (between the apex C and the apex A). Therefore, an apex angle of the apex B is about <NUM> degrees, which is close to a right angle of <NUM> degrees. Therefore, an elastic force acting on the cable CA from the elastically deformed first protrusion 14A can be suitably directed toward the center C1. By providing a plurality of such protrusions <NUM>, the cable CA can be stably supported, and a large holding force can be exerted for the cable CA due to a reaction force thereof.

Further, in the cross section perpendicular to the extending direction of the tube <NUM>, it is preferable that the protrusions <NUM> have a thickness of <NUM>% or more and <NUM>% or less of the length of the protrusions <NUM>, respectively. For example, the first protrusion 14A can be formed such that the leading end portion 14A1 of the first protrusion 14A has a thickness of <NUM>% or more and <NUM>% or less, and the base end portion 14A2 has a thickness of <NUM>% or more and <NUM>% or less. When the thickness of the protrusions <NUM> is too large with respect to their length, the protrusions <NUM> are less likely to bend, and thus, the tube <NUM> is less likely to be crushed. On the other hand, when the thickness of the protrusions <NUM> is too small with respect to their length, the elastic force acting on the cable CA from the protrusions <NUM> is insufficient. Therefore, by forming the protrusions <NUM> to have a thickness of <NUM>% or more and <NUM>% or less of the length of the protrusions <NUM>, it is possible to provide the tube <NUM> which is easily crushed and exerts a large holding force for the cable CA.

Further, in the cross section perpendicular to the extending direction of the tube <NUM>, it is preferable that a virtual inscribed circle C2 (<FIG>) circumscribing the protrusions <NUM> has a diameter of <NUM>% or more and <NUM>% or less of the inner diameter of the inner wall surface 12A.

When the protrusions <NUM> are formed such that the virtual inscribed circle C2 has a diameter of <NUM>% or less of the inner diameter of the inner wall surface 12A, the protrusions <NUM> can exert an elastic force on the cable CA having a diameter larger than <NUM>% of the inner diameter of the inner wall surface 12A. On the other hand, when the virtual inscribed circle C2 has a diameter of <NUM>% of the inner diameter of the inner wall surface 12A, two sides of a triangle where the position of the base end portion 14A2 of the first protrusion 14A contacting with the inner wall surface 12A is one apex (hereinafter, referred to as the "apex A", and an apex angle of the apex A is referred to as the "apex angle A"), the position near the tip of the leading end portion 14A1 contacting with the cable CA is one apex (hereinafter, referred to as the "apex B", and an apex angle of the apex B is referred to as the "apex angle B"), and the center C1 is one apex (hereinafter, referred to as the "apex C", and an apex angle of the apex C is referred to as the "apex angle C") are respectively defined such that the length between the apex B and the apex C is <NUM>% of the inner diameter of the inner wall surface 12A, and the length between the apex C and the apex A is <NUM>% thereof (between the apex C and the apex A). When the apex angle B is a right angle, the apex angle A is about <NUM> degrees. Since the tube approach a structure in which the protrusions protrude substantially in a vertical direction as the apex angle A becomes smaller than <NUM> degrees, the protrusions hinder the crushing of the tube, and it becomes difficult to crush the tube flat. Thus, by forming the protrusions <NUM> such that the virtual inscribed circle C2 has a diameter of <NUM>% or more and <NUM>% or less of the inner diameter of the inner wall surface 12A, it is possible to provide the tube <NUM> which can support the cable CA having a diameter larger than <NUM>% of the inner diameter of the inner wall surface 12A and can be easily crushed.

With the above configurations, according to the tube <NUM> of the present embodiment, it is possible to provide the tube which has a holding force and is easily crushed.

Note that the three protrusions <NUM> of the tube <NUM> are formed in a rotational symmetry of <NUM> degrees with reference to the center C1, but the present invention is not limited to this. For example, in the vertical cross section, the length of the first portion 12A1 of the inner wall surface 12A connecting the first protrusion 14A and the second protrusion 14B, the length of the second portion 12A2 of the inner wall surface 12A connecting the second protrusion 14B and the third protrusion 14C, and the length of the third portion 12A3 of the inner wall surface 12A connecting the third protrusion 14C and the first protrusion 14A may be different from each other.

Further, in the vertical cross section, the thickness of the leading end portion 14A1 of the first protrusion 14A, the thickness of the leading end portion 14B <NUM> of the second protrusion 14B, and the thickness of the leading end portion 14C1 of the third protrusion 14C may be different from each other.

Furthermore, in the vertical cross section, the length of the first protrusion 14A, the length of the second protrusion 14B, and the length of the third protrusion 14C may be different from each other.

Further, the shape and configuration of the thin-walled portion provided on the base end portion 14A2 and the like of the first protrusion 14A can be varied. For example, a notch may be provided in the base end portion 14A2. At this time, when a notch that opens to the first portion 12A1 of the inner wall surface 12A is provided, the protrusion 12A can be easily bent toward the first portion 12A1. Similarly, when notches that open to the inner wall surface 12A are provided in the base end portion 14B2 of the second protrusion 14B and the base end portion 14C2 of the third protrusion 14C, the protrusions 14B2, 14C2 can be easily bent toward the inner wall surface 12A.

Further, the diameter of the tube <NUM> can be appropriately designed according to the diameter of the cable CA to be inserted. For example, the inner diameter of the tube <NUM> may be, for example, either <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

Hereinafter, a tube <NUM> according to the second embodiment will be described. The tube <NUM> according to the present embodiment is different from the tube <NUM> having three protrusions in that two protrusions are provided. However, the parts that can be understood by those skilled in the art to have the same configuration as that of the tube <NUM> according to the first embodiment are denoted by the same name, and the description thereof is omitted or simplified.

<FIG> is a sectional view of the tube <NUM> in which the cable CA is inserted, taken along a direction perpendicular to the extending direction of the tube <NUM>. <FIG> is a perspective view of the tube <NUM> in a state where the cable CA is not inserted.

As shown in <FIG> and <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and two protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 22A of the body portion <NUM>, that is, a first protrusion 24A and a second protrusion 24B (hereinafter, these protrusions are collectively referred to as the "protrusions <NUM>").

The first protrusion 24A is provided to be inclined toward a first portion 22A1 of the inner wall surface 22A connecting the first protrusion 24A and the second protrusion 24B so that it has an angle θ2 with respect to the straight line L1 connecting the center C1 of the body portion <NUM> and the inner wall surface 22A (connecting portion between a base end portion 24A2 of the first protrusion 24A and the inner wall surface 22A) (here, in <FIG>, since the first protrusion 24A and the second protrusion 24B sandwich the cable CA, they are enlarged to form the angle θ2 larger than an angle in a state where the cable CAis not inserted). Similarly, the second protrusion 24B is provided to be inclined toward a second portion 22A2 of the inner wall surface 22A connecting the second protrusion 24B and the first protrusion 24A so that it has the angle θ2 with respect to the straight line L1.

Since the body portion <NUM> can have the same or similar configuration as the body portion <NUM>, the description thereof will be omitted. Further, the first protrusion 24A and the second protrusion 24B include a leading end portion 24A1 and the base end portion 24A2, and a leading end portion 24B1 and a base end portion 24B2, respectively, as in the case of the first protrusion 14A and the like.

Similar to the first embodiment, the thickness of the leading end portion (the "first thickness") may be greater than a thickness of the base end portion. The thickness of the leading end portion (the "first thickness") may be greater than a thickness of the weakened portion.

Similar to the first embodiment, a length from the inner wall surface to the weakened portion may be shorter than a length from the weakened portion to the leading end portion.

In the present embodiment, the first protrusion 24A and the second protrusion 24B are provided in a rotational symmetry of <NUM> degrees with reference to the center C1 of the body portion <NUM>. With such a configuration, when the cable CA is inserted through the tube <NUM>, the cable CA can be supported from two directions by each of the two leading end portions 24A1 and 24B <NUM>. As shown in <FIG>, the leading end portions 24A1 and 24B1 of respective protrusions <NUM> are deformed to the outer diameter side by the insertion of the cable CA, and therefore, press the cable CA from two directions toward the center C1 by the elastic force thereof. As a result, the tube <NUM> can exert a large holding force for the cable CA.

The plurality of protrusions <NUM> of the tube <NUM> are provided to be inclined in a direction approaching the inner wall surface 22A without going to the center C1 of the body portion <NUM>, respectively. Therefore, any straight line passing through the center C1 of the body portion <NUM> does not completely coincide with the extending directions of the protrusions <NUM>. Therefore, the deviation in the crushing difficulty depending on the direction is small, and the protrusions <NUM> do not significantly hinder the tube <NUM> from being crushed.

Since the protrusions <NUM> are inclined in the same direction along the circumferential direction, it is possible to suppress a problem that one protrusion is bent many times, and as a result, the outer peripheral surface 22B when completely crushed is greatly undulated and not flat, unlike the prior art.

Of the configuration of the tube <NUM>, the operational effect of the tube <NUM> based on the portion similar to the configuration of the tube <NUM> will be the same as in the first embodiment, and thus, the description thereof will be omitted.

Hereinafter, a tube <NUM> according to the third embodiment will be described. <FIG> are sectional views of the tube <NUM>, a tube <NUM> and a tube <NUM> taken along a direction perpendicular to the extending direction thereof, respectively.

The tubes according to the present embodiment are common in that the tubes include two protrusions protruding in a direction inclined with respect to an inner wall surface. Further, the two protrusions are provided so as not to be parallel to each other. The two protrusions are common in that, when an insert such as a cable is inserted, the protrusions sandwich the insert and press the insert in a direction toward the inner wall surface. Hereinafter, the configuration of each tube will be described. Note that the same or similar configurations as those of the tubes according to other embodiments and the parts that can be understood by those skilled in the art are denoted by the same name, and the description thereof is omitted or simplified.

As shown in <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and two protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 32A of the body portion <NUM>, that is, a first protrusion 34A and a second protrusion 34B.

The body portion <NUM> has a substantially quadrangular tubular shape in a cross section. Therefore, the inner wall surface 32A and an outer peripheral surface 32B each have four portions that are substantially perpendicular to each other, and form a substantially quadrangular shape with rounded corners in a vertical cross section.

From a first portion 32A1 that is one of the four portions of the inner wall surface 32A, the first protrusion 34A is provided to be inclined so that it has an angle θ3 with respect to the straight line L1 connecting the center C1 of the body portion <NUM> and the first portion 32A1 (connecting portion between the first protrusion 34A and the first portion 32A1).

From the same first portion 32A1, the second protrusion 34B is provided to be inclined so that it has an angle θ4 with respect to a straight line L2 connecting the center C1 of the body portion <NUM> and the first portion 32A1 (connecting portion between the second protrusion 34B and the first portion 32A1) (note that, in the present embodiment, the straight line L1 coincides with the straight line L2, and the angle θ3 and the angle θ4 are same value.

However, the first protrusion 34A and the second protrusion 34B are inclined in opposite directions along the circumferential direction and are provided such that a distance between them increases away from the first portion 32A1. As a result, the first protrusion 34A and the second protrusion 34B are provided non-parallel to each other.

According to the tube <NUM> having such a configuration, the first protrusion 34A and the second protrusion 34B are provided to be inclined with respect to the inner wall surface 32A, and any straight line passing through the center C1 of the body portion <NUM> does not completely coincide with the extending directions of the first protrusion 34A and the second protrusion 34B. Therefore, the deviation in the crushing difficulty depending on the direction is small, and the first protrusion 34A or the second protrusion 34B does not significantly hinder the tube <NUM> from being crushed.

Further, since the first protrusion 34A and the second protrusion 34B are provided so that the distance between them increases away from the first portion 32A1, the cable CA (an example of "a substantially tubular insert that has a substantially circular cross section perpendicular to the insertion direction into the tube <NUM>") can be sandwiched therebetween. At this time, the resultant force of the forces acting on the cable CA from the first protrusion 34A and the second protrusion 34B is directed toward a third portion 32A3 (not shown) facing the first portion 32A1 (to the right of the paper). Therefore, the first protrusion 34A and the second protrusion 34B are configured to sandwich the cable CA and to be able to press the cable CA in a direction toward the third portion 32A3. Thus, according to the tube <NUM> of the present embodiment, the cable CA can be supported at three points of the first protrusion 34A, the second protrusion 34B, and the third portion 32A3. At this time, the first protrusion 34A contacts a first fan-shaped portion F1 of an outer periphery of the cable CA having a central angle of <NUM> degrees, the second protrusion 34B contacts a second fan-shaped portion F2 having a central angle of <NUM> degrees, and the third portion 32A3 of the inner wall surface 32A contacts or faces a third fan-shaped portion F3 having a central angle of <NUM> degrees. Therefore, the tube <NUM> can stably support the cable CA, and can exert a large holding force for the cable CA due to a reaction force thereof.

Furthermore, even when the cable CA has a small diameter, the cable CA can be supported to be sandwiched between the first protrusion 34A and the second protrusion 34B because the first protrusion 34A and the second protrusion 34B are provided so that the distance between them increases away from the first portion 32A1. Note that the cable CA does not necessarily have to come into contact with the third portion 32A3 of the inner wall surface 32A.

As shown in <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and two protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 42A of the body portion <NUM>, that is, a first protrusion 44A and a second protrusion 44B. The tube <NUM> is different from the tube <NUM> in that the body portion <NUM> has a substantially annular tubular shape in the cross section. Since other configurations are the same or similar as those of the tube <NUM>, the same names are given and the description thereof is omitted or simplified.

Even in the tube <NUM> having such a configuration, the cable CA can be supported at three points of the first protrusion 44A, the second protrusion 44B, and the inner wall surface 42A because the first protrusion 44A and the second protrusion 44B can sandwich the cable CA therebetween and press the cable CA in a direction toward the inner wall surface 42A. At this time, the first protrusion 44A contacts the first fan-shaped portion F1 of the cross section of the cable CA having a central angle of <NUM> degrees, the second protrusion 44B contacts the second fan-shaped portion F2 having a central angle of <NUM> degrees, and the inner wall surface 42A contacts or faces the third fan-shaped portion F3 having a central angle of <NUM> degrees. Therefore, the tube <NUM> can stably support the cable CA, and can exert a large holding force for the cable CA due to a reaction force thereof.

As shown in <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and two protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 52A of the body portion <NUM>, that is, a first protrusion 54A and a second protrusion 54B. The first protrusion 54A and the second protrusion 54B are not provided in a rotational symmetry of <NUM> degrees. However, even in such a configuration, the cable CA can be supported at three points of the first protrusion 54A, the second protrusion 54B, and the inner wall surface 52A because the first protrusion 54A and the second protrusion 54B can sandwich the cable CA therebetween and press the cable CA in a direction toward the inner wall surface 52A. At this time, the first protrusion 54A contacts the first fan-shaped portion F1 of the cross section of the cable CA having a central angle of <NUM> degrees, the second protrusion 54B contacts the second fan-shaped portion F2 having a central angle of <NUM> degrees, and the inner wall surface 52A contacts or faces the third fan-shaped portion F3 having a central angle of <NUM> degrees. Therefore, the tube <NUM> can stably support the cable CA, and can exert a large holding force for the cable CA due to a reaction force thereof.

Of the configurations of the tube <NUM>, the tube <NUM>, and the tube <NUM>, the operational effect based on the portions similar to the configurations of the tube <NUM> and the like according to other embodiments will be the same as in the other embodiments, and thus, the description thereof will be omitted.

<FIG> show the cross sections of tubes <NUM> to <NUM> according to the modifications. These modifications can be applied to the tubes <NUM> to <NUM> according to each embodiment to the extent reasonably understood by those skilled in the art. Note that the parts that can be understood by those skilled in the art to have the same configurations as those of the tubes according to the respective embodiments are denoted by the same name, and the description thereof is omitted or simplified.

As shown in <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and three protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 62A of the body portion <NUM>, that is, a first protrusion <NUM> A, a second protrusion 64B, and a third protrusion 64C. As shown in <FIG>, each of the protrusions 64A to 64C is inclined with respect to the inner wall surface 62A and protrudes linearly in the cross section.

Furthermore, a leading end portion 64A1 and a base end portion 64A2 of the first protrusion 64A are provided to have a constant thickness. However, in an intermediate region of the base end portion 64A2, a thin-walled portion 64A21 (sometimes referred to as the "weakened portion") having a reduced thickness is provided.

Similarly, the second protrusion 64B is provided with a thin-walled portion 64B21 having a reduced thickness, and the third protrusion 64C is provided with a thin-walled portion 64C21 having a reduced thickness. Even with such a configuration, the cable CA can be easily inserted into the tube <NUM> because the thin-walled portions 64A21 to 64C21 are provided.

Note that each protrusion may have a linearly extending portion and a curved portion.

As shown in <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and three protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 72A of the body portion <NUM>, that is, a first protrusion 74A, a second protrusion 74B, and a third protrusion 74C. As shown in <FIG>, the protrusions 74A to 74C have different thicknesses and lengths, respectively. However, such a configuration also makes it possible to provide the tube which has a holding force and is easily crushed, as understood by those skilled in the art.

As shown in <FIG>, the tube <NUM> includes a long tubular body portion <NUM>, and three protrusions formed integrally with the body portion <NUM> and protruding from an inner wall surface 82A of the body portion <NUM>, that is, a first protrusion 84A, a second protrusion 84B, and a third protrusion 84C. The first protrusion 84A and the second protrusion 84B are inclined in opposite directions along the circumferential direction and are provided such that a distance between them increases away from the inner wall surface 82A. As a result, the first protrusion 84A and the second protrusion 84B are provided non-parallel to each other. However, unlike the tube <NUM>, the first protrusion 84A and the second protrusion 84B are provided to be curved in a direction away from each other such that the rate of increase in the distance between the first protrusion 84A and the second protrusion 84B increases away from the inner wall surface 82A (on the other hand, the first protrusion 34A and the second protrusion 34B are provided to be curved in a direction approaching each other such that the rate of increase in the distance between the first protrusion 34A and the second protrusion 34B of the tube <NUM> decreases away from the inner wall surface 32A. Therefore, when the first protrusion 84A and the second protrusion 84B sandwiches the cable therebetween, the force with which the first protrusion 84A and the second protrusion 84B push the cable toward the facing inner wall surface 82A can be increased. The third protrusion 84C supports such a cable. Therefore, the cable can be supported at three points. Such a configuration also makes it possible to provide the tube which has a holding force and is easily crushed, as understood by those skilled in the art.

Note that, in addition to the third protrusion 84C, a configuration may be adopted in which a fourth protrusion that is adjacent to the third protrusion 84C is provided to be inclined in a direction opposite to the third protrusion 84C, and the tube is supported at four points.

As shown in <FIG>, the tube <NUM> is characterized by the configuration of a body portion <NUM>. Unlike other embodiments, the thickness of the tubular body portion <NUM> is not constant in the circumferential direction. That is, the body portion <NUM> has a thin-walled portion 92A1 having a reduced thickness and a thick-walled portion 92A2 having an increased thickness, and a first protrusion 94A is provided to protrude at the boundary between the thin-walled portion 92A1 and the thick-walled portion 92A2. As a result, the first protrusion 94A is connected to the thin-walled portion 92A1 in a predetermined circumferential direction (counterclockwise direction on the paper), and is connected to the thick-walled portion 92A2 in the opposite direction (clockwise direction on the paper). With such a configuration, the first protrusion 94A can be easily bent toward the thin-walled portion 92A1.

Similarly, a second protrusion 94B is connected to a thin-walled portion 92B1 in the predetermined circumferential direction (counterclockwise direction on the paper), and is connected to a thick-walled portion 92B2 in the opposite direction (clockwise direction on the paper). A third protrusion 94C is connected to a thin-walled portion 92C1 in the predetermined circumferential direction (counterclockwise direction on the paper), and is connected to a thick-walled portion 92C2 in the opposite direction (clockwise direction on the paper). Further, like the other embodiments, the first protrusion 94A is provided to be inclined toward the portion of an inner wall surface 92A connecting the first protrusion 94A and the second protrusion 94B, the second protrusion 94B is provided to be inclined toward the portion of the inner wall surface 92A connecting the second protrusion 94B and the third protrusion 94C, and the third protrusion 94C is provided to be inclined toward the portion of the inner wall surface 92A connecting the third protrusion 94C and the first protrusion 94A.

Even with such a configuration, it is possible to provide the tube into which the cable CA can be easily inserted and which is easily crushed. Meanwhile, by providing the thick-walled portion 92A2 and the like, the elastic force toward the cable CA is increased, so that a large holding force can be exerted. However, it is not always necessary to provide the thick-walled portion 92A2 and the like. Further, when the thin-walled portion 92A1 and the like is provided, the first protrusion 94A and the like can be easily bent, but the shape, thickness, etc. of the thin-walled portion 92A1 and the like can be appropriately set according to the application. Furthermore, the first protrusion 94A and the like may be provided to be inclined in the opposite direction, that is, the first protrusion 94A and the like may be provided to be inclined toward the portion of the inner wall surface 92A connecting the first protrusion 94A and the like and the third protrusion 94C and the like. Additionally, the thickness and length of the first protrusion 94A and the like may be changed.

With the above configuration, according to these tubes, it is possible to provide the tube which has a holding force and is easily crushed. Note that these tubes can be manufactured, for example, by using extrusion molding using a mold.

Claim 1:
A cylindrical tube (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) into which an insert can be inserted, the tube comprising:
a plurality of protrusions (<NUM>, <NUM>, <NUM>, 44A, 44B, 54A, 54B, 64A, 64B, 64C, 74A, 74B, 74C, 84A, 84B, 84C, 94A, 94B, 94C) provided to protrude from an inner wall surface of the tube and to be inclined with respect to the inner wall surface, wherein each of the plurality of protrusions are provided non-parallel to each other, wherein each of the plurality of protrusions are inclined in a same direction along a circumferential direction of the tube, wherein at least one of the plurality of protrusions is provided in an arc shape gradually separated from the inner wall surface (12A, 22A, 32A, 42A, 52A, 62A, 72A, 82A) from a base end portion (14A2 to 14C2, 24A2, 64A2) to a leading end portion (14A1 to 14C1, 24B1, 24B1, 64A1).