Cable and cable manufacturing method

Abstract

To provide a technique that can protect a cable, and can maintain flexibility of the cable.SOLUTION: A cable comprises: a resin coated cable body 1; a glass fiber braided layer 2 which coats the cable body in a closely adhered manner; and a metal bellows case 4 which includes the glass fiber braided layer via a space 3. The cable body 1 coated by the glass fiber braided layer 2 is freely movable in an axial direction of the metal bellows case 4. Both ends of the glass fiber braided layer 2 are bound by a metal binding band 21.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to cables, such as power cables, and in particular to cables with protective coatings. [Background technology]

[0002] Generally, cables such as power cables are made up of a metal conductive core and a resin coating layer which is an insulating material.

[0003] Power cables are used in factories and other places, and are often pulled around when changing power sources, etc. In this case, the resin coating may be damaged by wear, etc. Damage to the resin coating may lead to electrical leakage, etc.

[0004] In response to this, the resin coating layer can be protected by further applying a metal coating (for example, Patent Document 1). Generally, metal is harder than resin and has excellent abrasion resistance. Therefore, even if the cable is routed when changing the power source, there is no risk of the resin coating being damaged. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 6-349365 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the cable body is metal-coated, but in many cases the cable is inserted into a hollow metal sheath. Generally, the resin-coated surface is not smooth, making it difficult to insert the cable into the metal sheath.

[0007] Furthermore, although the flexibility of the resin-coated cable itself is not an issue and there is no problem in running the cable, the flexibility of the cable as a whole is significantly reduced by the metal coating. Furthermore, the resin-coated surface is less slippery, further reducing the flexibility of the cable.

[0008] The present invention is intended to solve the above problems, and has an object to protect a cable and maintain the flexibility of the cable. [Means for solving the problem]

[0009] In order to achieve the above object, the cable of the present invention comprises a resin-coated cable body, a glass fiber braided layer that tightly covers the cable body, and a metal bellows case that encloses the glass fiber braided layer with a space between them.

[0010] Glass fiber has superior slipperiness compared to resin, which allows the cable body covered with the glass fiber braided layer to move easily inside the metal bellows case.

[0011] On the other hand, the unevenness of the glass fiber braid and the unevenness of the bellows engage appropriately to suppress excessive movement.

[0012] In other words, the metal bellows case can protect the cable body while allowing it to move freely and restricting movement.

[0013] More preferably, in the above cable, the cable main body covered with the glass fiber braided layer is movable in the axial direction of the metal bellows case.

[0014] This means that the cable body and the metal bellows case are not constrained by each other, reducing the risk of damage.

[0015] More preferably, in the cable, both ends of the glass fiber braided layer are bound together by metal binding bands.

[0016] This prevents the glass fibers from fraying, and the cable body and the metal bellows case remain free from any constraints.

[0017] More preferably, in the above cable, the diameter of the cable main body covered with the glass fiber braided layer is 1.2 to 1.6 times the diameter of the cable main body, and the inner diameter of the metal bellows case is 1.5 to 3.0 times the diameter of the cable main body.

[0018] This creates an appropriate space, allowing for both freedom of movement and engagement between the recesses and protrusions.

[0019] More preferably, in the above cable, the metal bellows case is formed by spiraling a long plate and engaging a first L-shaped portion provided at one end of the short axis of the long plate with a second L-shaped portion provided at the other end of the short axis of the long plate.

[0020] This improves the flexibility of the metal bellows case.

[0021] More preferably, the angle formed by the first L-shaped portion is different from the angle formed by the second L-shaped portion.

[0022] This further improves the flexibility of the metal bellows case.

[0023] To achieve the above object, in the method for manufacturing a cable, the glass fiber braided layer is formed while covering the cable body.

[0024] This improves the adhesion between the cable body and the glass fiber braided layer. [Effects of the Invention]

[0025] According to the present invention, the cable can be protected and the flexibility of the cable can be maintained. [Brief explanation of the drawings]

[0026] [Figure 1]Schematic diagram [Figure 2] Schematic diagram [Figure 3] Metal bellows case configuration diagram [Figure 4] Metal bellows case configuration diagram [Figure 5] Another working example [Figure 6] Variations [Figure 7] Modified example of use [Figure 8] Variations DETAILED DESCRIPTION OF THE INVENTION

[0027] ~Configuration~ Fig. 1 shows a schematic configuration of a cable according to an embodiment of the present invention, and Fig. 2 is a schematic cross-sectional view of the cable.

[0028] The cable comprises a cable body 1, a glass fiber braided layer 2, and a metal bellows case 4.

[0029] The cable body 1 is made of a core material covered with resin. There are no particular restrictions on the type of resin. Generally, PVC (polyvinyl chloride), PE (polyethylene), FEP (Teflon (registered trademark)), etc. are often used.

[0030] Terminals 11 are provided on both ends of the cable body 1 for connection to a power source or the like.

[0031] The glass fiber braided layer 2 is in close contact with the cable body 1 to cover the cable body 1. The glass fiber covering may be achieved by forming a glass fiber braided tube and inserting the cable body 1 into the tube to integrate the cable body 1, or by braiding the glass fibers around the cable body 1 to integrate the cable body 1. The latter method provides better adhesion and is more suitable for the purpose of the present application.

[0032] Both ends of the glass fiber braided layer 2 are bound with metal binding bands 21. This prevents the glass fibers from fraying and ensures that the layer is integrated with the cable body. However, if heat resistance is not required, the layer does not have to be made of metal.

[0033] The surface of the glass fiber braided layer 2 has superior slipperiness compared to the resin of the cable body 1 .

[0034] The metal bellows case 4 contains the cable covered with the glass fiber braided layer 2 with a space 3 therebetween.

[0035] The material of the metal bellows case 4 is not particularly limited, but in the prototype model it was made of SUS.

[0036] The detailed shape of the metal bellows case 4 will be described separately later.

[0037] 2 is a schematic cross-sectional view of the case. The dimensions shown in the drawings are examples to aid in understanding the present invention, and are not limited to these dimensions.

[0038] The diameter of the cable body 1 is φ7 mm, the thickness of the glass fiber braided layer 2 is 1.5 mm, and a glass fiber coated cable with a diameter of φ10 mm is formed.

[0039] The inner diameter of the metal bellows case 4 is set to φ16 mm and the outer diameter is set to φ22 mm, thereby ensuring a space 3 of 3 mm on each side.

[0040] The diameter of the cable main body covered with the glass fiber braided layer 2 is preferably 1.2 to 1.6 times (e.g., approximately 1.4 times) the diameter of the cable main body 1. The inner diameter of the metal bellows case 4 is preferably 1.5 to 3.0 times (e.g., approximately 2.3 times) the diameter of the cable main body 1. This ensures that the space 3 is 0.1 to 0.5 times (e.g., approximately 0.4 times) the diameter of the cable main body 1.

[0041] In the present embodiment, the cable main body 1 and the glass fiber braided layer 2 are integrated by braiding, whereas the cable main body 1 covered with the glass fiber braided layer 2 and the metal bellows case 4 are not constrained by each other, and the cable main body 1 covered with the glass fiber braided layer 2 is free to move in the axial direction of the metal bellows case 4. The slipperiness of the glass fiber braided layer 2 does not hinder movement.

[0042] However, the surface of the glass fiber braided layer 2 is uneven due to the braiding, and the inner wall of the metal bellows case 4 is uneven due to the bellows, so while they can move freely, slight friction occurs when the uneven surfaces come into contact with each other.

[0043] Furthermore, the above dimensional relationship ensures both freedom of movement and engagement between the recesses and protrusions.

[0044] In this embodiment, the length of the cable main body 1 covered with the glass fiber braided layer 2 is slightly longer than the length of the metal bellows case 4. At both ends of the metal bellows case 4, the cable main body 1 covered with the glass fiber braided layer 2 is exposed.

[0045] The detailed configuration of the metal bellows case 4 is not particularly limited, but in order to maintain the flexibility of the cable main body, it is preferable that the flexibility of the metal bellows case 4 be as high as possible.

[0046] In general, metal bellows cases are often formed by arranging metal rings in the axial direction and engaging adjacent metal rings to form an integrated unit. In the embodiment of the present application, such a metal bellows case may be used, but a configuration that further improves flexibility may also be used.

[0047] 3 and 4 are diagrams showing an example of the structure of a metal bellows case. For example, a long plate has an end face that is roughly S-shaped, and both ends of the S shape are L-shaped. That is, an L-shaped portion 41, which is one end of the S shape, and an L-shaped portion 42, which is the other end of the S shape, are formed on the short axis of the long plate. The long plate is bent in the longitudinal direction into a spiral shape, and one L-shaped portion 41 engages with the other L-shaped portion 42, thereby forming the long plate into a case shape.

[0048] In this case, it is preferable that the angle formed by L-shaped portion 41 is different from the angle formed by L-shaped portion 42. In the example shown in the figure, the angle formed by L-shaped portion 41 is an obtuse angle (for example, 120 degrees), while the angle formed by L-shaped portion 42 is approximately 90 degrees. As a result, L-shaped portion 41 and L-shaped portion 42 do not come into surface contact with each other, ensuring an appropriate degree of freedom and improving flexibility.

[0049] Furthermore, when the metal bellows case is bent significantly, the inside contracts, but the spiral acts as an elastic element, preventing the outside from expanding excessively, maintaining the engagement. This allows for both improved flexibility and heat resistance.

[0050] ~Actions and Effects~ The operation when the cable of this embodiment is routed for the purpose of changing the power supply or the like will be described.

[0051] The metal bellows case 4 and the cable main body 1 covered with the glass fiber braided layer 2 are not constrained by each other and are free to move in the axial direction. The metal bellows case 4 is also highly flexible.

[0052] With this configuration, when the cable main body 1 is pulled around, the surface of the cable main body 1 covered with the glass fiber braided layer 2 comes into contact with the inner wall of the metal bellows case 4. The metal bellows case 4 follows the movement of the cable main body 1 as appropriate. In particular, by increasing the flexibility of the metal bellows case 4, the metal bellows case 4 can follow the movement of the cable main body 1.

[0053] Furthermore, the flexibility of the metal bellows case 4 and the cable main body 1 covered with the glass fiber braided layer 2 is not hindered by each other, thereby maintaining the flexibility of the cable as a whole.

[0054] At this time, the unevenness on the surface of the glass fiber braided layer 2 and the unevenness on the bellows of the metal bellows case 4 engage appropriately, transmitting movement, and the uneven engagement is released when excessive stress is applied due to movement. In addition, the glass fiber braided layer 2 has minute gaps that absorb impacts caused by contact.

[0055] Furthermore, the engagement between the braided irregularities and the bellows irregularities can suppress excessive movement.

[0056] Furthermore, if there is a risk of excessive movement, the metal binding band 21 engages with the bellows unevenness to suppress excessive movement.

[0057] As a result, the cable moves as a unit while maintaining sufficient flexibility, and the cable body 1 is protected from damage such as abrasion.

[0058] When pulling the cable of this embodiment, the bellows outer wall of the metal bellows case 4 may get caught on an obstacle on the floor. In this case, the impact on the metal bellows case 4 is not transmitted to the cable main body 1, and the risk of disconnection is reduced. In this respect, the cable main body 1 is also protected.

[0059] Furthermore, the glass fiber braided layer 2 has minute gaps, which together with the space 3 form a heat insulating layer, thereby providing the cable of this embodiment with both fire resistance and heat resistance.

[0060] 5 is an explanatory diagram of another operation. In a factory, the cable of this embodiment is often wired in a suspended state.

[0061] The metal bellows case 4 and the cable main body 1 covered with the glass fiber braided layer 2 are not constrained by each other and can move freely in the axial direction, but the metal bellows case 4 can maintain its proper positioning due to the loose engagement between the surface irregularities of the glass fiber braided layer 2 and the bellows irregularities of the metal bellows case 4.

[0062] If the metal bellows case 4 is not properly positioned, it can be easily moved and repositioned to an appropriate position since it is axially movable.

[0063] In the present application, the cable is not limited to a power cable, but it is more effective if it can accommodate the high flexibility of a power cable.

[0064] ~Variations~

[0065] Fig. 6 shows one modified example. In this embodiment, the length of the cable main body 1 covered with the glass fiber braided layer 2 and the length of the metal bellows case 4 are approximately the same (the glass fiber braided layer 2 is slightly exposed at both ends of the metal bellows case 4), whereas in the modified example, the length of the metal bellows case 4 is extremely short.

[0066] For example, the length of the metal bellows case 4 is set to be less than half, one-fourth, or one-tenth of the length of the cable body 1 covered with the glass fiber braided layer 2 .

[0067] Figure 7 shows an example of how to use this modified example. Suppose that there is a significant risk of damage to a specific location when unwinding a cable (for example, due to an obstacle such as a protrusion). A metal bellows case 4 is placed at that location and easily fixed in place.

[0068] When the end of the cable body 1 covered with the glass fiber braided layer 2 is pulled, the cable body 1 covered with the glass fiber braided layer 2 smoothly passes through the metal bellows case 4. While the cable is being unwound, the metal bellows case 4 protects the cable body 1 from abrasion and impact.

[0069] It also protects the cable in place once it is in place, with the tongue and groove engagement helping to maintain proper position.

[0070] 8 shows another modified example, which has a plurality of extremely short metal bellows cases 4. The metal bellows cases 4 are arranged according to the number of risk locations. [Explanation of symbols]

[0071] 1 Cable body 2. Glass fiber braided layer 3 space 4 Metal bellows case 11 Cable terminal 21 Cable ties 41,42 L-shaped part

Claims

1. A cable that is laid to change power sources in a location including a factory, a resin-coated cable body; a glass fiber braided layer that covers the cable body in close contact with the cable body; a metal bellows case that encloses the glass fiber braided layer with a space therebetween; Equipped with the cable main body covered with the glass fiber braided layer is movable in the axial direction of the metal bellows case, Both ends of the glass fiber braided layer are bound by metal binding bands, At both ends, the cable body is exposed from the glass fiber braid layer. A cable characterized by:

2. the diameter of the cable main body covered with the glass fiber braided layer is 1.2 to 1.6 times the diameter of the cable main body; The inner diameter of the metal bellows case is 1.5 to 3.0 times the diameter of the cable main body; A space is formed between the metal bellows case and the cable body covered with the glass fiber braided layer on both sides thereof, and one side of the space is 0.1 to 0.5 times the diameter of the cable body.

2. The cable according to claim 1.

3. The metal bellows case is formed by forming a long plate into a spiral shape, and engaging a first L-shaped portion provided at one end of a short shaft of the long plate with a second L-shaped portion provided at the other end of the short shaft of the long plate.

2. The cable according to claim 1.

4. The angle formed by the first L-shaped portion is different from the angle formed by the second L-shaped portion.

4. The cable according to claim 3.

5. The glass fiber braided layer is formed while covering the cable body.

2. The method for manufacturing a cable according to claim 1.

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