JP3982120B2 - Low temperature flexible cable - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a low-temperature flexible cable used for a mobile device in a freezer at −50 ° C. or lower.
[0002]
[Prior art]
Conventional freezers are generally within −50 ° C., and low temperature flexible cables that can be bent even at low temperatures are used in automatic transfer equipment such as stacker cranes and traversing carts for work in the warehouse.
[0003]
As the low-temperature flexible cable, 2PNCT (ethylene-propylene rubber (EPR) insulated chloroprene sheath cab tire cable) and 2CT (natural rubber insulated natural rubber sheath cab tire cable) having excellent cold resistance are generally used.
[0004]
In a freezer having a temperature of −50 ° C. or less that has recently started to be built, a conventional natural rubber, ethylene-propylene rubber (EPR) or chloroprene sheath is insufficient in cold resistance and may cause brittle fracture.
[0005]
For this reason, it is used by the method of always energizing the wire core of the low-temperature flexible cable to keep the cable warm (substitute for the heater wire).
[0006]
[Problems to be solved by the invention]
However, in this case, there are problems such that the cable cannot be replaced and that the refrigerator capacity needs to be increased in consideration of heat radiation from the cable.
[0007]
Further, as shown in FIG. 4, a bare conductor 30 is twisted to form a core 31, and an extruded insulating layer 32 made of resin is provided on the outer periphery of the core 31, and a metal is formed on the extruded insulating layer 32. Although there is a technique (Japanese Utility Model Publication No. 53-33804) for increasing the cold resistance of the cable 34 by forming the braid 33, there is a problem that sufficient flexibility cannot be obtained.
[0008]
Therefore, an object of the present invention is to provide a low-temperature flexible cable that solves the above-described problems, has low heat dissipation in the freezer, and can maintain sufficient flexibility even at a low temperature of −50 ° C. or lower.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a low-temperature flexible cable that can be bent at a low temperature of −50 ° C. or less to form a plurality of insulation-coated conductors by applying insulation coating to the conductive wires. A core is formed by bundling, and a sheath having a structure in which a cold resistant material made of any of metal, Tetron (registered trademark), and carbon fiber is braided is formed on the outer periphery of the core .
[0010]
In this low-temperature flexible cable, when the insulation-coated conductor freely moves in the sheath when bent, the resistance to bending is small, and sufficient flexibility can be maintained even at a low temperature of −50 ° C. or lower. . Moreover, since it is not necessary to energize all the time, heat dissipation in the freezer can be minimized.
[0011]
Further, the sheath is formed in two layers, one layer of metal wire, Tetron yarn consisting of (R), thereby forming either a carbon fiber, the other layer polyamide textiles or Ranaru cold fibers It is good to form with.
[0012]
Alternatively, the sheath is a metal wire, Tetron yarn consisting of (R), and any of carbon fibers, may be formed by blend polyamide textiles or Ranaru cold fibers.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0014]
As shown in FIG. 1, a low-temperature flexible cable 1 includes a plurality of insulation-coated conductors 3 formed by applying insulation coating to a conductor 2 and a braid formed on the outer periphery of a bundle of these insulation-coated conductors 3. A sheath 4 having a structure.
[0015]
The insulating coated conductor 3 has a coating layer 5 made of polyethylene (PE). Since polyethylene becomes hard at a low temperature of −50 ° C. or lower, it is not suitable for the sheath 4 that predominantly determines the flexibility of the low-temperature flexible cable 1, but compared to the diameter of the low-temperature flexible cable 1. It is sufficiently thin and can be sufficiently used as an insulator for the conductor 2 that does not significantly affect the flexibility of the low-temperature flexible cable 1.
[0016]
The insulated conductor 3 is twisted so as to open the center of the low-temperature flexible cable 1 to form the core 6. When the cable 1 is bent, the insulated conductors 3 are mutually connected in the sheath 4. Each can move freely without interference.
[0017]
The sheath 4 is made of metal, and is formed by braiding a particularly soft annealed copper wire.
[0018]
The sheath 4 is covered with a core 6 with a slight margin so that the inner insulation conductor 3 can be freely moved when bent.
[0019]
Describe the action.
[0020]
When a force in the bending direction acts on the low-temperature flexible cable 1 at a low temperature of −50 ° C. or lower, each insulation-coated conductor 3 forming the core 6 of the low-temperature flexible cable 1 is loosely moved while moving apart. It is easily bent with the sheath 4. This becomes more significant as the diameter of the low-temperature flexible cable 1 increases.
[0021]
At this time, since the sheath 4 is formed by braiding an annealed copper wire, the sheath 4 is bent without difficulty while changing the interval between the braided annealed copper wires.
[0022]
In this way, the conductor 2 is coated with insulation to form a plurality of insulation-coated conductors 3, and the insulation-coated conductors 3 are bundled to form a core 6, and a braid made of annealed copper wire on the outer periphery of the core 6 Since the sheath 4 having the structure is formed to form the low-temperature flexible cable 1, heat radiation in the freezer can be stopped to the minimum necessary, and sufficient flexibility is maintained even at a low temperature of −50 ° C. or lower. be able to.
[0023]
Moreover, since the sheath 4 is formed by braiding an annealed copper wire, the core 6 can be shielded from the outside, and further, electric shock can be prevented.
[0024]
In addition, although polyethylene was used as an insulation coating body, it is not restricted to this, You may use other resin materials, such as Teflon (trademark) and a polyurethane which have the same flexibility as polyethylene.
[0025]
The sheath 4 may be made of Tetron (registered trademark) yarn or carbon fiber instead of the annealed copper wire. The flexibility of the low-temperature flexible cable 1 can be further increased and can be manufactured at low cost.
[0026]
And although the insulation coating conductor 3 shall be twisted and bundled, it may be simply assembled and bundled.
[0027]
Another embodiment will be described.
[0028]
The low temperature flexible cable 10 shown in FIG. 2 is obtained by changing the sheath 4 of the low temperature flexible cable 1 shown in FIG.
[0029]
The sheath 11 of the low-temperature flexible cable 10 is composed of an inner layer 12 formed directly on the outer periphery of the core 6 and an outer layer 13 formed on the outer periphery of the inner layer 12. Yes.
[0030]
The inner layer 12 is formed by braiding polyamide fibers (nylon yarns), which are cold resistant fibers, and protects the core 6 against impact force applied from the outside.
[0031]
The outer layer 13 is formed by braiding an annealed copper wire as a metal, and shields the inner layer 12 and the core 6 from the outside.
[0032]
Describe the action.
[0033]
When the low-temperature flexible cable 10 is bent, the insulated conductor 3 forming the core 6 is bent while freely moving in the inner layer 12, and the polyamide fiber forming the inner layer 12 is bent while moving the distance between the fibers, The outer layer 13 is bent while moving the interval between the annealed copper wires. At this time, the core 6 and the inner layer 12, and the inner layer 12 and the outer layer 13 are bent while being displaced, and are easily bent.
[0034]
In this way, the sheath 11 is formed in two layers, and one layer (outer layer 13) is formed of soft copper wire, and the other layer (inner layer 12) is formed of polyamide fiber. Can have a function as a shielding layer, and a layer braided with polyamide fibers can have a function as a protective layer.
[0035]
Further, by forming a layer (inner layer 12) of polyamide fiber, a heat insulating layer that hardly circulates air can be formed inside the low temperature flexible cable 10, and slight heat generated from the core 6 is kept inside when energized. In addition, heat dissipation into the freezer can be prevented, and the insulation coated conductor 3 can be kept warm to further increase the flexibility of the low temperature flexible cable 10.
[0036]
The inner layer 12 is provided with a braid made of polyamide fiber and the outer layer 13 is provided with a braid made of annealed copper wire. However, the present invention is not limited to this, and conversely, the inner layer 12 is provided with a braid made of annealed copper wire. The outer layer 13 may be provided with a braid made of polyamide fiber.
[0037]
The annealed copper wire may be replaced with Tetoron (registered trademark) yarn or carbon fiber.
[0038]
Another embodiment will be described.
[0039]
A low temperature flexible cable 20 shown in FIG. 3 is obtained by changing the sheath 4 of the low temperature flexible cable 1 shown in FIG.
[0040]
The sheath 21 of the low-temperature flexible cable 20 is braided (woven and knitted) by blending a soft copper wire as a metal wire and a polyamide fiber.
[0041]
Since the sheath 21 is formed by blending an annealed copper wire and a polyamide fiber, it is possible to obtain good flexibility, obtain a shielding property, and manufacture the sheath 21 at low cost. .
[0042]
The annealed copper wire may be replaced with Tetron (registered trademark) yarn or carbon fiber.
[0043]
【The invention's effect】
In short, according to the present invention, the following excellent effects can be obtained.
[0044]
(1) Heat dissipation in the freezer is small, and sufficient flexibility can be maintained even at a low temperature of −50 ° C. or lower.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a low-temperature flexible cable showing a preferred embodiment of the present invention.
FIG. 2 is a cross-sectional view of a low-temperature flexible cable showing another embodiment.
FIG. 3 is a cross-sectional view of a low-temperature flexible cable showing another embodiment.
FIG. 4 is a cross-sectional view of a conventional low-temperature flexible cable.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Low temperature flexible cable 2 Conductor 3 Insulation coated conductor 4 Sheath 6 Core 10 Low temperature flexible cable 11 Sheath 12 Inner layer (the other layer)
13 Outer layer (one layer)
20 Low temperature flexible cable 21 Sheath

Claims (3)

In a low-temperature flexible cable that can be bent at a low temperature of −50 ° C. or lower, a conductor is coated with an insulation coating to form a plurality of insulation-coated conductors, and these insulation-coated conductors are bundled to form a core to form a metal, tetron (registered trademark), low temperature flexibility cable sheath of braided structure cold material consisting of either carbon fiber, characterized in that formed on the outer periphery of the core. The sheath is formed in two layers, a layer of one metal wire, yarn made of Tetron (registered trademark), and forming in one of carbon fiber, the other layer of polyamide textiles or Ranaru cold fibers The low-temperature flexible cable according to claim 1. It said sheath, metal wire, Tetron yarn consisting of (R), and any one of carbon fiber, low temperature flexibility cable according to claim 1 which is formed by blend polyamide textiles or Ranaru cold fibers .

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