JP2005022762A - Cable guide tube, and packing carton for cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact cable guide tube and a compact packing carton for a cable, for smoothly drawing out the cable. <P>SOLUTION: This cable guide tube has a truncated cylindrical shape for inserting a cable 12, and formed to satisfy the expression of R<SP>2</SP>=[(1.008×ln(k)-1.927×k)]<SP>2</SP>+D<SP>2</SP>, where the minimum inside diameter of a small diameter end part is D; the projection length on the small diameter end part is k; and the bending diameter of the cable 12 is R. The projection length k satisfies k≥7 mm, when calculated from conditions of 20≤D≤55 mm, and R≥8d×1/2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cable guide tube used for sequentially pulling out one end of a cable bundle bundled in a coil shape and accommodated in a packaging box outward from the side surface of the packaging box, and a cable package to which the cable guide tube is attached. Regarding the box.
[0002]
[Prior art]
The cable bundle 13 bundled in a coil shape as shown in FIG. 2 is housed in a cardboard packaging box 10 and transported to an arbitrary location. When used, the cable bundle is put into the packaging box 10 as shown in FIG. It has been conventionally known that the cables 12 are sequentially drawn out from the outlet 16 provided on the side surface of the packaging box 10 in the accommodated state.
[0003]
In order to smoothly pull out the cable 12 from the packaging box 10 as shown in FIG. 1, a cable guide tube 11 formed in a truncated conical cylindrical shape is used. The cable guide tube 11 is disposed so as to cross the cable bundle 13 and is attached so that one end is connected to an outlet 16 provided on a side surface of the packaging box 10 (see Patent Document 1).
[0004]
[Patent Document 1]
JP 2001-63784 A
[Problems to be solved by the invention]
By the way, the conventional techniques as described above have the following problems to be solved.
Recently, it has been studied to apply a pulp mold, which is free from environmental pollution problems and advantageous in terms of cost, to a cable guide tube.
The cable guide tube can smoothly pull out the cable when the inner diameter of the end portion on the cable entrance side is larger. However, since the cable guide tube is used by being embedded in the cable bundle, when the outer diameter increases, the cable bundle is lifted in the height direction, and a correspondingly high packaging box is required. become.
[0006]
On the other hand, in the case of a cable guide tube made of pulp mold, if the outer diameter is small, the tip of the tube is crushed into an oval due to the weight of the cable, etc. There is a risk that smooth pull-out work may be hindered. The optimum conditions when the cable guide tube is made of pulp mold are unknown and have few deterministic factors.
[0007]
In addition, the packaging box containing the cable bundle is stacked in multiple stages (4 to 5 stages) during transportation and storage, but a larger number can be stacked when the height of the packaging box itself is lower, Since work efficiency becomes good, the compactness of the cable guide tube is also demanded from this point.
[0008]
The present invention has been made paying attention to the above points, and an object of the present invention is to provide a more compact cable guide tube and cable packaging box that can smoothly draw out a cable.
[0009]
[Means for Solving the Problems]
The present invention adopts the following configuration in order to solve the above points.
<Configuration 1>
When the pulp mold is formed into a truncated conical cylindrical shape through which the cable can be inserted, the minimum inner diameter of the small diameter end is D, the protrusion length on the small diameter end is k, and the bending diameter of the cable is R. A cable guide tube configured to satisfy the following formula.
R ² = [(1.008 × ln (k) −1.927) × k] ² + D ² where 20 ≦ D ≦ 55 mm, and k calculated from the condition of R ≧ 8d × 1/2. K ≧ 7 mm.
[0010]
The protrusion length k on the small-diameter end side of the cable guide tube means that the cable guide tube is exposed outwardly from the inner peripheral surface of the cable bundle when it is embedded in the coil-wrapped cable bundle. The length of the tube tip.
A pulp mold is a well-known paper-made body in which paper fibers such as waste newspaper, waste magazine, and pulp are melted and made into a liquid state, and then made up with a metal net attached to a mold having a predetermined shape. For example, a metal mesh is attached to the surface of a metal mold with many holes, water and air are drawn from the back of the metal mesh, pulp slurry is attached to the surface of the metal mesh, dehydrated, and then molded into an arbitrary shape from the metal mesh. The pulp is removed and dried to obtain a product. The pulp mold can be easily recycled and can be remanufactured from a used cable guide tube. And no harmful substances are used in the manufacturing process, and even if incinerated, no hydrogen chloride or black smoke is emitted. Furthermore, even if the pulp mold is buried in the ground, it is easily decomposed by bacteria in the ground and returned to the soil, so that the environment is taken into consideration. In addition, a raw material such as a cardboard box can be used to improve the compression strength of the tube itself. Furthermore, it is possible to reduce the thickness of the tube by incorporating a paper strength enhancer (environmentally friendly chemicals).
The main object of the cable is a twisted pair cable for LAN. However, any flexible plastic cable having an outer diameter of about 3 to 7 mm is an object of the present invention.
Since the cable guide tube has a configuration that satisfies the above formula, it has an optimum outer diameter and length in accordance with the outer diameter of the cable to guide the cable through.
[0011]
<Configuration 2>
The cable guide tube according to Configuration 1, wherein the cable guide tube has a flange at a large-diameter end.
[0012]
By having a flange at the large-diameter end, it can be firmly installed in the cable packaging box during use.
[0013]
<Configuration 3>
A cable packaging box for storing a cable bundle bundled in a coil shape, wherein a minimum inner diameter of a small diameter end portion of a cable guide tube having a truncated cone shape through which a cable can be inserted by a pulp mold is D, the cable guide R ² = [(1.008 × ln (k) −1.927) × k] ² + D ² , where k is the protruding length of the small-diameter end of the tube and R is the allowable bending diameter of the cable. , 20 ≦ D ≦ 55 mm, and k calculated from the condition of R ≧ 8d × 1/2, and the cable guide tube configured so that the equation of k ≧ 7 mm is satisfied, A cable packaging box characterized by being arranged so as to cross the inside of the cable bundle toward the center of the cable bundle and the large-diameter end portion side toward an outlet provided on a side surface.
[0014]
In Configuration 3, the cable guide tube of Configuration 1 is arranged at a predetermined position in the cable packaging box. By attaching the cable guide tube of Configuration 1, the cable in the cable packing box can be pulled out smoothly without causing kinking, and the size of the packing box can be considerably reduced in size.
[0015]
<Configuration 4>
The cable packaging box according to Configuration 3, wherein the cable packaging box is a cardboard box.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described using specific examples.
FIG. 4 shows an embodiment of a cable guide tube (hereinafter referred to as a tube) of the present invention.
As shown in FIG. 4, the tube 11 is formed by a pulp mold so as to have a truncated conical cylindrical shape having a flange 15 at a large-diameter end.
The tube 11 is arranged and used in the packaging box as follows. That is, as shown in FIG. 1, the small diameter end side of the tube 11 faces the axial center of the cable bundle 13, and the large diameter end side faces the outlet 16 (FIG. 3) provided on the side surface of the packaging box. It is mounted so as to traverse the inside of the bundle 13. Then, as shown in FIG. 2, the flange 15 is disposed in the corrugated cardboard packaging box 10 so as to be firmly attached to the side surface of the corrugated cardboard packaging box 10. At this time, the small diameter end portion side of the tube 11 protrudes from the inner peripheral surface of the cable bundle 13 toward the axis of the cable bundle 13 by 20 to 30 mm. However, the tip of the small-diameter end of the tube 11 is prevented from protruding to the axial center of the cable bundle 13. This is because, if the protruding length is too long, the cable that will be described later cannot be pulled out smoothly.
In use, the cable end on the inner diameter side of the cable bundle 13 is inserted from the small diameter end portion of the tube, and as shown in FIG. 3, for sequentially pulling out continuously from the outlet 16 provided on the side surface of the packaging box. Do a guide.
[0017]
FIG. 7 is a schematic diagram of the tube 11, and a reference numeral indicating each dimension is attached.
As shown in FIG. 7, the tube 11 has a minimum inner diameter D of the small diameter end, a protruding length on the small diameter end side, that is, a portion on the small diameter end side of the tube 11, and the inner peripheral surface of the cable bundle 13. When the length of the portion protruding inward from the k is k and the allowable bending diameter of the cable 12 to be guided (FIG. 1) is R,
R ² = [(1.008 × ln (k) −1.927) × k] ² + D ²
However, k is calculated from the condition of 20 ≦ D ≦ 55 mm and R ≧ 8d × 1/2, and k ≧ 7 mm is satisfied.
[0018]
For example, in the case of the tube 11 shown in FIG. 4, the length (L) is 120 mm, the minimum outer diameter of the large diameter end is 65 mm, the minimum outer diameter of the small diameter end is 35 mm, and the minimum inner diameter (D ) Is 22 mm, and k is 20 to 30 mm. In order to provide a predetermined compression strength and the like, the wall thickness is set to 2.5 mm or more, and the total weight of the tube is set to 22 g (gram) or more.
[0019]
Next, an experiment comparing the tube according to the present invention and a conventional tube and the result thereof will be described. The experiment is a condition that the cable must not be kinked when the cable is pulled out of the box.
In the experiment, a twisted pair cable for LAN having an outer diameter of 5.4 mm was used. Two types of cables having a total length of 300 m and 100 m were prepared, and cable bundles were respectively configured. A plurality of sets of these cable bundles and the following various tubes accommodated in a predetermined packing box were prepared.
As the various tubes 11, tubes having different dimensions were prepared as shown in FIGS.
[0020]
Since all the tubes 11 are made of a pulp mold, the minimum inner diameter (D) is set to 22 mm or more as a limit of the diameter reduction. The reason for this is that the allowable bending diameter of the cable is specified to be 8 times or more of the cable outer diameter (5.4φ × 8 = 43.2 mm) according to LAN standards TIA / EIA-568B, JIS X 5150, etc. Therefore, it was decided that the inner diameter of about 1/2 of the standard was used as a guide, the bending diameter when pulling out the cable by the thickness and length of the tube, and that the pressure strength of the pulp mold was a problem. (It is an empirical value that the pulp mold with a minimum inner diameter (D) of 22 mm or less is uneasy in terms of strength).
<Experimental conditions>
[0021]
[Experiment 1] (Cable extraction experiment with different tube diameters)
FIG. 11 shows the conditions of Experiment 1.
The tube (1) is shown in FIG. 5, and the tube (2) is shown in FIG.
[0022]
[Experiment 2] (Cable extraction experiment based on tube length)
FIG. 12 shows the conditions of Experiment 2.
The tube (5) is as shown in FIG.
[0023]
[Experiment 3] (tube crushing experiment by tube length)
This experiment doubles as a test to check whether the tube is crushed by the cable weight due to shaking during product storage or transportation.
FIG. 13 shows the conditions of Experiment 3.
<Experimental result>
[0024]
[Experiment 1] (Cable extraction experiment with different tube diameters) FIG. 14 shows the results of Experiment 1. Both the tube (1) and the tube (2) show the results when all the cables of 300 m are drawn from three boxes.
In this experiment, the tube protrusion length k was set to 0 mm for both the tube (1) and the tube (2).
The cable minimum bending diameter is defined as 8 times the outer diameter of the cable (5.4φ × 8 = 43.2 mm) or more, and the tube (2) having a diameter smaller than this is defined as NG.
FIG. 8 shows the minimum bending condition of the cable 12 when the cable is pulled out from the packing box in the stage of Experiment 1, 11A in FIG. 8 (a) shows the tube (1), and 11B in FIG. 8 (b) Tube (2) is shown. It can be seen that the bending diameter of the cable 12 is larger in the tube (1) than in the tube (2), and kinks are less likely to occur.
[0025]
[Experiment 2] FIG. 15 shows the result of Experiment 2 (cable drawing experiment based on the length of the tube). Both the tube (2) to the tube (5) show the results when all the cables of 300 m are drawn from the three boxes.
In this experiment, the tube protrusion length k increases in the order of the tube (2) to the tube (5).
The cable minimum bending diameter was defined to be 8 times (5.4φ × 8 = 43.2 mm) or more than the cable outer diameter. Therefore, the tube (2) and the tube (3) having a diameter smaller than this were determined as NG.
11c of FIG.8 (c) has shown the tube (5). Since the tube (5) has a long tube protrusion length k, it can be seen that the cable has a large bending diameter and is unlikely to cause kinking.
[0026]
FIG. 16 shows the result of Experiment 3 for [Experiment 3] (tube crushing experiment based on the length of the tube). Both the tube (2) and the tube (5) show the result of observing the crushing condition when a load of about 1000 N (Newton) is applied to three boxes each containing a 300 m cable. The cable weight was about 100 N at 300 m, and was calculated to be 1000 N with a safety factor of 2 for 5 boxes.
<Experimental considerations>
[0027]
From the results of Experiment 1, it was found that the cable bending diameter (R) when pulling out the cable depends on the minimum inner diameter (D) of the tube.
Since the minimum inner diameter (D) of the tube (1) is 54 mm, the cable bending diameter (R) is 55 mm, and the minimum inner diameter (D) of the tube (2) is 22 mm, so the cable bending diameter (R) is 20 mm. . The cable bending diameter (R) is a diameter formed in a loop when a cable wound in a coil shape and twisted tries to return to a straight line.
FIG. 9 shows a change in the bending of the cable 12 inserted into the tube 11 in the stage of Experiment 1.
As shown in FIG. 9, the cable 12 is drawn while drawing a circle on the circumference of the inside of the tube, and therefore depends on the inner diameter of the tube. Therefore, if the inner diameter of the tube is 8 times or less than the outer diameter of the cable, the cable is likely to be kinked, and the transmission performance of the cable itself is likely to deteriorate.
[0028]
From the results of Experiment 2, it was found that the cable bending diameter (R) can be greatly corrected by increasing the tube protrusion length (k) even when the tube minimum inner diameter (D) is not more than 8 times the cable outer diameter. .
According to Experiments 1 and 2, according to the present invention, the tube small-diameter side tip is not crushed because it does not receive the cable weight, and the cables do not intersect in the vicinity of the tube small-diameter side tip. It was found that the cable can be pulled out smoothly.
[0029]
Calculations were made based on this experiment and formulated so that they could be applied to other packaging boxes. This will be described below.
FIG. 7 is an explanatory view showing dimensions of each part of the tube. In FIG. 7, D is the minimum inner diameter of the tube, k is the protruding length of the tube, R is the allowable bending diameter of the cable, and L is the total length of the tube.
An equivalent equation ignoring the change in distance due to the taper of the tube 11 and the tube thickness is expressed as equation (1).
R ² = k ² + D ² (1)
[0030]
FIG. 17 shows a comparison between the theoretical value obtained by equation (1) and the result of Experiment 2.
As shown in FIG. 17, with respect to the theoretical value and the experimental value, the error increases as the protrusion length k increases. This is thought to be due to the rigidity of the cable itself. Therefore, a correction coefficient y corresponding to the size of the protrusion length k as shown in FIG. 18 was calculated. FIG. 10 shows the correction coefficient graph.
[0031]
The correction coefficient y is expressed by Equation 2.
y = 1.0084 × ln (k) −1.927 Formula (2)
However, k is the tube projection length (mm), and k> = 7.
From Equation 1 and Equation 2, the following Equation 3 is obtained.
R ² = [(1.008 × ln (k) −1.927) × k] ² + D ² Formula (3)
[0032]
Moreover, from the above consideration, the tube 11 having a reduced diameter can be used for other packing boxes as long as the following application range is applied. That is,
K calculated from the condition of 20 ≦ D ≦ 55 mm and R ≧ 8d × 1/2. However, k ≧ 7 mm.
[0033]
FIG. 19 shows a usage example of the cable packing box.
Although the comparative example of FIG. 19 is a conventional tube and packing box, there is no problem such as a kink when pulling out the cable because the minimum inner diameter of the tube is large.
In Experimental Example 1, the entire packing box is reduced in size by reducing the tube minimum inner diameter (D). For the cable pull-out, the tube protrusion length (k) is 30 mm. Absent. From equation (3), the tube protrusion length (k) is 27.2 mm or more.
Since Experimental Example 2 has a short cable length, the tube protrusion length (k) can be ensured even if the tube length is short.
[0034]
FIG. 20 shows the merit when the present invention is applied to a packing box for a twisted pair cable for LAN having a total length of 300 m. The comparative example of FIG. 20 is a conventional packaging box using a tube.
As is clear from FIG. 20, the tube of the present invention shown in Experimental Example 1 can achieve a reduction in diameter of about 60 to 70% in the outer diameter ratio and about 88% in the volume ratio compared with the conventional tube. Was able to reduce the space. And by arranging the tube at a predetermined position in the packaging box, the volume of the packaging box was reduced by about 80%.
Many packaging boxes that store cable bundles are stacked at the time of transportation or storage, but as the packaging box volume is made compact, more transportation and storage can be performed, and the work efficiency is greatly affected. .
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which tubes are arranged in a cable bundle in a packaging box.
FIG. 2 is a perspective view showing a state when a cable bundle is stored in a packing box.
FIG. 3 is a perspective view showing a state in which the cables of the cable bundle are pulled out from the packing box.
FIG. 4 is a longitudinal sectional view showing an embodiment of the tube of the present invention.
FIG. 5 is a longitudinal sectional view showing an example of a conventional tube.
FIG. 6 is a longitudinal sectional view showing an example of a conventional tube.
FIG. 7 is an explanatory diagram of a tube.
FIGS. 8A and 8B are diagrams showing the minimum bending degree of the cable when the cable is pulled out from the packing box, wherein FIG. 8A is an explanatory view showing the bending state of the tube (1), and FIG. 8B is a drawing showing the bending state of the tube (2); Explanatory drawing which shows, (c) is explanatory drawing which shows the bending condition of a tube (5).
FIG. 9 is an explanatory diagram showing changes in the bending of a cable inserted into a tube.
FIG. 10 is a diagram showing a correction coefficient with respect to a tube protrusion length.
FIG. 11 is an explanatory diagram showing conditions for a cable drawing experiment based on a difference in tube diameter.
FIG. 12 is an explanatory diagram showing conditions for a cable drawing experiment according to the length of the tube.
FIG. 13 is an explanatory diagram showing conditions for a tube crushing experiment depending on the length of the tube.
FIG. 14 is an explanatory diagram showing a result of a cable drawing experiment based on a difference in tube diameter.
FIG. 15 is an explanatory diagram showing a result of a cable drawing experiment according to the length of the tube.
FIG. 16 is an explanatory diagram showing a result of a tube crushing experiment according to the length of the tube.
FIG. 17 is an explanatory diagram showing a comparison between a theoretical value and a result of an experimental value.
FIG. 18 is an explanatory diagram showing a correction coefficient for the tube protrusion length.
FIG. 19 is an explanatory view showing a usage example of the cable packing box.
FIG. 20 is an explanatory diagram showing the merit of using a tube.
[Explanation of symbols]
10 packing box 11 cable guide tube 12 cable 13 cable bundle 15 flange 16 outlet

Claims (4)

When the pulp mold is formed into a truncated conical cylindrical shape through which the cable can be inserted, the minimum inner diameter of the small-diameter end is D, the protrusion length on the small-diameter end is k, and the bending diameter of the cable is R. A cable guide tube configured to satisfy the following formula.
R ² = [(1.008 × ln (k) −1.927) × k] ² + D ²
However, k is calculated from the condition of 20 ≦ D ≦ 55 mm and R ≧ 8d × 1/2, and k ≧ 7 mm. The cable guide tube according to claim 1,
The cable guide tube has a flange at a large-diameter end portion. A cable packaging box for storing a bundle of cables bundled in a coil,
The minimum inner diameter of the small-diameter end of the cable guide tube that is made into a truncated cone shape through which the cable can be inserted by the pulp mold is D, the protrusion length on the small-diameter end side of the cable guide tube is k, and the allowable bending diameter of the cable Is R,
R ² = [(1.008 × ln (k) −1.927) × k] ² + D ² , where 20 ≦ D ≦ 55 mm,
And k calculated from the condition of R ≧ 8d × 1/2, and a cable guide tube configured so that an expression of k ≧ 7 mm is satisfied,
A cable packaging box characterized in that the small-diameter end portion faces the center of the cable bundle, and the large-diameter end portion crosses the cable bundle toward an outlet provided on a side surface. In the cable packaging box according to claim 3,
A cable packaging box comprising a cardboard box.

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