Silo temperature measurement cable

Abstract

To provide a silo temperature measuring cable in which even when resin case is fractured, the falling of the fractured resin case can be suppressed and the occurrence of such a problem that the silo temperature measuring cable cannot measure silo temperature can be suppressed.SOLUTION: A silo temperature measuring cable comprises: a wire rope; a plurality of conductors extending from the top to the bottom of the wire rope, and wound around an outer periphery of the wire rope; a sensing unit incorporated into at least one of the plurality of conductors; a resin sheath provided on the outside of the plurality of conductors, and covering the plurality of conductors and the sensing unit; and a sheath fall prevention stopper provided on the wire rope below the resin sheath.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a silo temperature measuring cable. [Background technology]

[0002] There has been a need to measure and monitor the temperature inside a silo and maintain it at a predetermined temperature. For example, a silo temperature measuring cable is used as a means for measuring the temperature inside a silo. The silo temperature measuring cable is attached to a hanging part provided at the top of the silo and supported inside the silo, allowing the temperature inside the silo to be measured.

[0003] For example, Patent Document 1 describes a conductor cable for transmitting temperature signals, which has multiple temperature signal transmission conductors in the center and a surrounding reinforcing part including a wire rope that is slidable longitudinally relative to the multiple conductors. The reinforcing part is a resin sheath made of polyethylene resin or the like.

[0004] However, in the conductor cable of Patent Document 1, if the resin sheath breaks, the broken and fallen resin sheath will be mixed into the stored goods stored in the silo. Therefore, the fallen resin sheath must be removed from the stored goods. Furthermore, if the resin sheath falls, the temperature signal transmission conductor will be exposed, and there is a risk that the exposed temperature signal transmission conductor will rub against the stored goods, making it impossible to measure the temperature. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Publication No. 01-089416 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present disclosure is to provide a silo temperature measuring cable that can prevent the broken resin sheath from falling even if the resin sheath breaks, and can prevent temperature measurement from becoming impossible. [Means for solving the problem]

[0007] [1] A silo temperature measuring cable comprising: a wire rope; a plurality of conductors extending from above to below the wire rope and wound around the outer periphery of the wire rope; a sensing unit incorporated in at least one of the plurality of conductors; a resin sheath provided on the outside of the plurality of conductors and covering the plurality of conductors and the sensing unit; and a stopper for preventing the sheath from falling, provided on the wire rope below the resin sheath. [2] The silo temperature measuring cable described in [1] above, wherein the stopper for preventing the sheath from falling is provided at the part of the wire rope where the part extending from above to below and the lower end part extending from below to above meet. [3] The silo temperature measuring cable described in [1] above, wherein the stopper for preventing the sheath from falling is provided at the lower end of the wire rope. [4] The silo temperature measuring cable according to any one of the above [1] to [3], wherein the resin sheath is made of polypropylene resin. [5] The silo temperature measuring cable according to any one of the above [1] to [4], wherein the resin sheath has a tensile strength of 25.0 MPa or more. [6] The silo temperature measuring cable according to any one of the above [1] to [5], wherein the resin sheath is made of a block polypropylene resin. [7] The silo temperature measuring cable according to any one of the above [1] to [6], wherein the resin sheath has a tensile strength of 700% or more. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a silo temperature measuring cable that can prevent the broken resin sheath from falling even if the resin sheath breaks, and can prevent temperature measurement from becoming impossible. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a front view showing an example of a silo temperature measuring cable according to the first embodiment. [Figure 2] FIG. 2 is a schematic diagram showing an example of a state in which the silo temperature measuring cable of the first embodiment is suspended from a silo. [Figure 3] FIG. 3 is a front view showing an example of a silo temperature measuring cable according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a detailed description will be given based on an embodiment.

[0011] The inventors analyzed why the resin sheath of a silo temperature measurement cable suspended in a silo breaks and falls inside the silo. As an example of the analysis results, they found that grain added from the top of the grain silo hits the resin sheath of the silo temperature measurement cable while suspended in the silo, causing the sheath to stretch and eventually break and fall into the stored materials inside the silo. The broken and fallen resin sheath becomes contaminated with the stored materials inside the silo as foreign matter, which requires the foreign resin sheath to be removed from the stored materials, resulting in additional costs. Furthermore, when the broken resin sheath falls, the wire core covered by the resin sheath is exposed. Grain hitting the exposed wire core may cause a break, or the conductor may be exposed, potentially making it impossible to measure temperature using the silo temperature measurement cable.

[0012] After extensive research, the inventors discovered that by providing a stopper below the resin sheath to prevent the sheath from falling, even if the resin sheath of a silo temperature measuring cable breaks, the broken resin sheath can be prevented from falling and temperature measurement can be prevented from becoming impossible.Based on this finding, the present disclosure has been completed.

[0013] The silo temperature measuring cable of the embodiment comprises a wire rope, a plurality of conductors extending from the top to the bottom of the wire rope and wound around the outer periphery of the wire rope, a sensing unit incorporated in at least one of the plurality of conductors, a resin sheath provided on the outside of the plurality of conductors and covering the plurality of conductors and the sensing unit, and a stopper for preventing the sheath from falling, provided on the portion of the wire rope below the resin sheath.

[0014] (First embodiment) Fig. 1 is a front view showing an example of a silo temperature measuring cable according to the first embodiment. In Fig. 1 and Fig. 3 described later, the resin sheath 5, the stopper 6 for preventing the sheath from falling, and the molded part 7 are shown in a see-through manner to make the configuration of the wire rope 2, the conductor 3, and the sensing part 4 easier to understand.

[0015] As shown in Figure 1, the silo temperature measuring cable 1 of this embodiment includes a wire rope 2, multiple conductors 3, a sensing unit 4, a resin sheath 5, and a stopper (hereinafter simply referred to as a stopper) 6 for preventing the sheath from falling. The silo temperature measuring cable 1 is a cable for measuring the temperature inside a silo.

[0016] As shown in FIG. 2, which will be described later, the wire rope 2 constituting the silo temperature measuring cable 1 is installed in a suspended state inside the silo 80, and supports from the center a plurality of conductors 3 wound around the outer periphery of the wire rope 2. The wire rope 2 is a stranded wire made by twisting together a plurality of metal wires. The outer periphery of the wire rope 2 may also be covered with a pressure tape (not shown).

[0017] As shown in Figure 1, the upper end of the silo temperature measuring cable 1 is provided with an upper loop portion 21 formed by folding back the wire rope 2 in a loop shape. A protective metal fitting 22 such as a thimble is attached to the inside of the upper loop portion 21. The portion of the wire rope 2 where the portion extending from below to above and the upper end portion extending from above to below are joined together is bound by a metal sleeve 23.

[0018] The plurality of conductor wires 3 extend from above to below the wire rope 2 and are wound around the outer periphery of the wire rope 2. The plurality of conductor wires 3 provided along the axial direction of the wire rope 2 are wound around the wire rope 2 in a spiral shape while contacting each other, as shown in FIG.

[0019] Here, an example is shown in which the silo temperature measuring cable 1 has 12 conductors 3, but the number of conductors 3 is not particularly limited as long as it is multiple, and is set appropriately depending on the use of the silo temperature measuring cable 1, etc.

[0020] The conductor wire 3 is a stranded wire made by twisting together copper wires, for example, and the outer periphery of the conductor wire 3 is covered with an insulator (not shown).

[0021] The sensing unit 4 is a component that senses temperature, and is incorporated into at least one of the plurality of conducting wires 3. One sensing unit 4 is incorporated into one conducting wire 3. For example, as shown in FIG. 1 , each of the plurality of sensing units 4 is incorporated into a different conducting wire 3 among the plurality of conducting wires 3.

[0022] The sensing unit 4 is not particularly limited as long as it is a member that senses temperature, and may be configured, for example, by a resistance temperature detector or a thermocouple.

[0023] When the silo temperature measuring cable 1 is equipped with multiple sensing units 4, each of the multiple sensing units 4 is provided at a different position along the axial direction of the wire rope 2 and senses the temperature at a predetermined height within the silo. In Figure 1, five sensing units 4 are incorporated into each of the five conductors 3, and each sensing unit 4 can sense the temperature at five heights within the silo.

[0024] Here, an example is shown in which the silo temperature measuring cable 1 has five sensing units 4, but the number of sensing units 4 is not particularly limited as long as it is one or more, and is set appropriately depending on the application of the silo temperature measuring cable 1, etc.

[0025] The resin sheath 5 is provided on the outside of the plurality of conducting wires 3 in the portion where the plurality of conducting wires 3 are wound around the outer periphery of the wire rope 2, and covers the plurality of conducting wires 3 and the sensing unit 4 from the outside. Inside the cylindrical resin sheath 5, the plurality of conducting wires 3 wound around the outer periphery of the wire rope 2 and one or more sensing units 4 incorporated into the plurality of conducting wires 3 are arranged.

[0026] The resin sheath 5 extending along the longitudinal direction of the silo temperature measuring cable 1 extends, for example, to the lower ends of the multiple conductors 3 extending from above to below the wire rope 2. The resin sheath 5 is made of polypropylene resin, polyethylene resin, or the like.

[0027] It is preferable that the resin sheath 5 satisfy at least one of the following requirements: that the resin sheath 5 be made of polypropylene resin, and that the tensile strength of the resin sheath 5 be 25.0 MPa or more. If the resin sheath 5 satisfies any one of these requirements, the mechanical strength of the resin sheath 5 is improved, and therefore partial damage or breakage of the resin sheath 5 caused by grains or the like poured from the top of the silo hitting the resin sheath 5 of the silo temperature measuring cable 1 can be suppressed, even if the thickness of the resin sheath is about the same as that of a resin sheath made of polyethylene resin or the like, i.e., even if the thickness of the resin sheath 5 is not increased, partial damage or breakage of the resin sheath 5 can be suppressed.

[0028] In this way, breakage of the resin sheath 5 can be suppressed without increasing the thickness, thereby substantially reducing the weight of the silo temperature measuring cable 1. Furthermore, breakage of the resin sheath 5 can be suppressed by controlling the material and mechanical properties of the resin sheath 5 without complicating the structure of the silo temperature measuring cable 1. As a result, the life of the silo temperature measuring cable 1 can be extended, thereby reducing the frequency of replacing the silo temperature measuring cable 1 for silos, which requires manual work at heights of several tens of meters.

[0029] From this perspective, it is preferable that the resin sheath 5 satisfy both the requirements that the resin sheath 5 be made of polypropylene resin and that the tensile strength of the resin sheath 5 be 25.0 MPa or more. In particular, it is more preferable that the resin sheath 5 be made of block polypropylene resin. Furthermore, the tensile strength of the resin sheath 5 is more preferably 35.0 MPa or more, and even more preferably 40.0 MPa or more.

[0030] The tensile strength of the resin sheath 5 is measured using a dumbbell-shaped test piece in accordance with 4.16.4.1 Tensile strength of JIS C 3005:2014.

[0031] Similarly to the above, from the viewpoint of preventing breakage of the resin sheath 5, the elongation force of the resin sheath 5 is preferably 700% or more, and more preferably 750% or more.

[0032] The tensile strength of the resin sheath 5 is measured using a dumbbell-shaped test piece in accordance with 4.16.4.2 Elongation of JIS C 3005:2014.

[0033] The resin sheath 5 may also contain additives such as antioxidants.

[0034] The stopper 6 is provided in a portion of the wire rope 2 below the resin sheath 5. In addition, a lower end loop portion 24 formed by folding back the wire rope 2 in a loop shape is provided at the lower end of the silo temperature measuring cable 1 below the stopper 6. The stopper 6 is provided at the joint of the portion of the wire rope 2 that extends from above downward and the lower end portion that extends from below upward.

[0035] The stopper 6 may be swaged to the wire rope 2 by, for example, compression or crimping, or may be joined to the wire rope 2 by welding such as laser welding. The stopper 6 is provided on the wire rope 2, but is not provided on the conductor 3 or the resin sheath 5.

[0036] The stopper 6 is preferably made of a copper-based material including copper and copper alloys, an aluminum-based material including aluminum and aluminum alloys, or stainless steel. From the viewpoint of oxidation resistance, an aluminum-based material or stainless steel is preferable.

[0037] The stopper 6 is provided on the wire rope portion below the resin sheath 5, and therefore can prevent the resin sheath 5 from falling. Furthermore, even if the resin sheath 5 breaks, the broken resin sheath 5 is supported from below by the stopper 6 provided on the wire rope 2, and therefore the broken resin sheath 5 can be prevented from falling. Furthermore, even if the resin sheath 5 breaks, the conductor portion incorporating the sensing unit 4 can remain covered with the resin sheath 5 for a long period of time, and therefore the silo temperature measuring cable 1 can be prevented from becoming unable to measure the temperature for a long period of time.

[0038] In order to further prevent the broken resin sheath 5 from falling, the outer shape of the stopper 6 is preferably larger than the outer shape of the resin sheath 5 .

[0039] Furthermore, it is preferable that a molded section 7 be provided above the stopper 6 and at the portion where the lower end of the resin sheath 5 and the wire rope 2 join together. The lower portions of the multiple conductors 3 are covered with the resin sheath 5 and further sealed from the outside by the molded section 7. The molded section 7 is made of resin.

[0040] If the silo temperature measuring cable 1 did not have the molded portion 7, static electricity would be generated when the conductor portion exposed downward from the lower end of the resin sheath 5 came into contact with grain or the like poured into the silo from the top, and grain powder or the like would adhere to the silo temperature measuring cable 1, which could make it impossible to measure the temperature with the silo temperature measuring cable 1. However, by providing the silo temperature measuring cable 1 with the molded portion 7, the generation of static electricity can be suppressed, further preventing the silo temperature measuring cable 1 from becoming unable to measure the temperature.

[0041] FIG. 2 is a schematic diagram showing an example of a state in which the silo temperature measuring cable of the first embodiment is suspended from a silo.

[0042] As shown in Figure 2, the silo temperature measuring cable 1 can be attached to the silo 80 by hooking the upper end loop portion 21 of the silo temperature measuring cable 1 onto a hanging portion 81 provided at the top of the silo 80. In this way, the silo temperature measuring cable 1 can be maintained in a suspended state from the top to the bottom within the silo 80. The multiple sensing units 4 provided on the silo temperature measuring cable 1 are arranged at different height positions within the silo 80.

[0043] The storage material S to be stored in the silo 80 is loaded into the silo 80 through an inlet 82 provided at the top of the silo 80. The storage material S stored in the silo 80 is discharged to the outside of the silo 80 through a discharge outlet 83 provided at the bottom of the silo 80.

[0044] The silo temperature measuring cable 1, which is installed while hanging from the top of the silo 80, senses the temperature at different height positions within the silo 80 using each sensing unit 4, and measures the temperature at different height positions within the silo 80 by sending the signals obtained by the sensing units 4 to a measuring instrument 84.

[0045] Such a silo temperature measuring cable 1 can be used in various silos 80 such as agricultural silos like grain silos and coal silos.

[0046] According to the first embodiment described above, by providing a stopper below the resin sheath, the silo temperature measuring cable can prevent the broken resin sheath from falling even if the resin sheath breaks, and can also prevent temperature measurement from becoming impossible.

[0047] (Second embodiment) FIG. 3 is a front view showing an example of a silo temperature measuring cable according to the second embodiment.

[0048] In the following embodiments, the same components as those in the silo temperature measuring cable 1 of the first embodiment are denoted by the same reference numerals, and redundant explanations will be omitted or simplified.

[0049] In the second embodiment, the configuration of the silo temperature measuring cable 1a is basically the same as that of the silo temperature measuring cable 1 in the first embodiment, except that the configuration of the lower part is different. Therefore, the different configuration will be mainly described here.

[0050] As shown in Figure 3, in the silo temperature measuring cable 1a of the second embodiment, the stopper 6 is provided at the lower end of the wire rope 2, which is the lower end of the silo temperature measuring cable 1a. In the silo temperature measuring cable 1, the lower end of the wire rope 2 faces upward, but in the silo temperature measuring cable 1a, the lower end of the wire rope 2 faces downward.

[0051] Unlike the silo temperature measuring cable 1, the lower end of the silo temperature measuring cable 1a does not have the lower end loop portion 24 of the wire rope 2, but has a linear stopper 6. Therefore, compared to the silo temperature measuring cable 1, twisting of the silo temperature measuring cable 1a caused by grains or the like put in from the top of the silo hitting the lower end of the silo temperature measuring cable 1a can be suppressed, which further reduces the possibility of temperature measurement being impossible for a long period of time.

[0052] According to the second embodiment described above, by providing a stopper at the lower end of the wire rope, which is the lower end of the silo temperature measuring cable, twisting of the silo temperature measuring cable can be suppressed, thereby further preventing temperature measurement from becoming impossible.

[0053] Although the embodiments have been described above, the present invention is not limited to the above embodiments, but includes all aspects encompassed by the concept and scope of the claims of the present disclosure, and can be modified in various ways within the scope of the present disclosure. [Explanation of symbols]

[0054] 1, 1a Silo temperature measuring cable 2 wire rope 21 Upper loop 22 Protective fittings 23 Metal sleeve 24 Lower loop 3 conductors 4. Sensing section 5 Resin sheath 6 Sheath drop prevention stopper 7 Mold section 80 Silo 81 Hanging part 82 Inlet 83 Outlet 84 Measuring instruments S Storage

Claims

1. Wire rope and a plurality of conductors extending from above to below the wire rope and wound around the outer periphery of the wire rope; a sensing unit incorporated in at least one of the plurality of conductors; a resin sheath provided on the outer side of the plurality of conducting wires and covering the plurality of conducting wires and the sensing unit; a sheath drop prevention stopper provided in a portion of the wire rope below the resin sheath; A silo temperature measuring cable.

2. The silo temperature measuring cable according to claim 1, wherein the sheath fall prevention stopper is provided at the joint of the part of the wire rope that extends from above downward and the lower end part that extends from below upward.

3. The silo temperature measuring cable according to claim 1 , wherein the sheath drop prevention stopper is provided at a lower end of the wire rope.

4. The silo temperature measuring cable according to any one of claims 1 to 3, wherein the resin sheath is made of polypropylene resin.

5. The silo temperature measuring cable according to any one of claims 1 to 3, wherein the resin sheath has a tensile strength of 25.0 MPa or more.

6. The silo temperature measuring cable according to any one of claims 1 to 3, wherein the resin sheath is made of a block polypropylene resin.

7. The silo temperature measuring cable according to any one of claims 1 to 3, wherein the resin sheath has a tensile strength of 700% or more.

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