JP2010033755A - Non-halogen flame-retardant wire for pressure contact and its connecting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the possibility of conduction failure by restraining insulation coating of non-halogen wires from deforming due to external force added at pressure-contact connection, and therefore, restraining degradation of wire-retention force by a connector, and preventing the wire from easily coming off, by insertion-coupling the non-halogen wire into and with the connector, in a wire terminal processing. <P>SOLUTION: For the non-halogen flame-retardant wire for pressure contact made by insulation-coating a conductor with a plurality of strands coaxially twisted, and used by being insertion-coupled with and connected with the connector in pressure contact, an outer diameter of the center strand is formed larger than that of others around the center strand, and gaps are formed between each two adjacent strands. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pressure-free non-halogen flame retardant electric wire excellent in terminal processability and a connection method thereof.

  Conventionally, polyvinyl chloride (PVC) has been mainly used for insulation coating of electric wires for equipment. Since PVC has rubber-like elasticity and excellent mechanical properties, it is strong against deformation due to external force applied when the wire is inserted and fitted into the connector and press-contacted in the end processing of the wire, In addition, it is resistant to trauma during wiring. However, since PVC releases harmful halogen gas during combustion, the transition to non-halogenation is in progress. Non-halogen materials have poor rubbery elasticity and poor mechanical properties compared to PVC. For this reason, when using a non-halogen material for the insulation coating of an electric wire, the modification | change, such as devising the mixing | blending of material, is performed. However, this modification is not easy. For example, when the strength is improved, there is a problem that elongation and flexibility are lowered.

  On the other hand, there are several wire connection methods that are adopted as terminal processing for equipment wires, but in the case of equipment wires with a thin diameter of several millimeters, they are usually called pressure connection or crimp connection. A connection method is adopted. Among these, the press contact connection is a method in which an electric wire is inserted and fitted into a connector formed of a resin frame, and the conductor of the electric wire is press connected to a contact in the connector. This method can eliminate the strip work that exposes the conductor end of the wire for connection, and when using a batch connection type connector, multiple wires can be connected together by pressure contact. It is often used as an excellent method.

  However, in the non-halogen wire using a non-halogen material for the insulation coating, since the rubber-like elasticity and mechanical characteristics of the insulation coating are not sufficient, the external force applied when inserting and fitting the wire into the connector and press-connecting, Deformation tends to occur in the insulation coating of the electric wire. When the insulation coating is deformed, the electric wire holding force by the connector is reduced, and the electric wire is easily pulled out from the connector, which may cause poor conduction. In particular, in a connector having a narrow hook for preventing disconnection at the electric wire insertion portion of the connector, a large external force is applied to the insulating coating of the electric wire when passing through the hook, and the insulating coating is often deformed.

  On the other hand, as a prior art document, in Patent Document 1, an outer layer composed of a plurality of strands is provided on the outer periphery of an inner layer that is composed of two or more layers of wires and is further coated with an insulator on the outer periphery. In the insulating coated conductor, the inner layer is composed of a strand having a diameter larger than that of the outer layer, a gap is formed between the adjacent strands of the outer layer, and a resin serving as an insulator is formed in the gap. A filled insulated wire is disclosed. In this insulation-coated electric wire, the gap is filled with the resin to increase the adhesion strength between the conductor and the insulator.

JP 2003-51214 A

  As described above, in the non-halogen electric wire using a non-halogen material for the insulation coating, since the rubber-like elasticity and mechanical properties of the insulation coating are not sufficient, in the end processing of the electric wire, the electric wire is inserted and fitted into the connector, When the pressure connection is made, the insulation coating of the electric wire is likely to be deformed by an external force applied. When the insulation coating is deformed, the electric wire holding force by the connector is reduced, and the electric wire is easily pulled out from the connector, which may cause poor conduction.

  Further, although Patent Document 1 does not refer to a non-halogen electric wire, even if it refers to a non-halogen electric wire, the insulation-coated electric wire described in Patent Document 1 is formed between adjacent strands of the outer layer. When the gap is filled with a resin that becomes an insulator, and the movement of the wire is constrained by the resin filled in the gap, when inserting and fitting the wire into the connector, and press-connecting In addition, it is considered inevitable that the insulation coating is deformed by the applied external force. As a result, similar to the above-described conventional technology, the electric wire holding force by the connector is reduced, the electric wire is likely to be pulled out from the connector, and there is a risk of causing a conduction failure.

  Therefore, the object of the present invention is to solve the problems of the prior art, and in the end processing of the electric wire, the external force applied when inserting and fitting the electric wire into the connector and press-connecting causes deformation in the insulation coating of the non-halogen electric wire. Non-halogen flame retardant wire for pressure welding with excellent terminal processability, which eliminates the possibility of poor electrical conduction by suppressing the decrease in wire holding force by the connector and preventing the wire from coming out of the connector. And providing a connection method thereof.

  In order to achieve the above object, the invention of claim 1 is a non-halogen for pressure welding which is used by providing an insulation coating on a conductor in which a plurality of strands are concentrically twisted, inserted into a connector, and pressure-bonded. In the flame-retardant electric wire, the outer diameter of the central strand is formed larger than the outer diameter of other strands around the central strand, and a gap is formed between other adjacent strands. Providing non-halogen flame retardant electric wires for use.

  According to the non-halogen flame retardant electric wire for pressure welding according to claim 1, the outer diameter of the central strand is formed larger than the outer diameters of other strands around the central strand, and a gap is formed between other adjacent strands. In the end processing of electric wires, when the wire is inserted and fitted into the connector and press-contacted, the conductor cross section is first easily deformed by the applied external force, and the external force is absorbed by the deformation of the conductor cross section. Therefore, the deformation of the insulation coating is effectively suppressed. As a result, the decrease in the electric wire holding force by the connector is suppressed, the electric wire is prevented from being easily pulled out from the connector, and the possibility of poor conduction is eliminated. .

In the invention of claim 2, when the outer diameter of the central strand is R and the outer diameter of the other strand is R ₀ , the relationship value between the two expressed by the following formula is in the range of 0.05 to 0.15. 2. The non-halogen flame retardant electric wire for pressure welding according to claim 1, wherein the non-halogen flame retardant electric wire is provided.

[Equation 1]
(R−R ₀ ) / R
According to the non-halogen flame retardant electric wire for pressure welding according to claim 2, the above-mentioned effect is ensured by setting the outer diameter (R) of the central strand and the outer diameter (R ₀ ) of the other strand to a specific relationship value Obtainable. When this relation value is less than 0.05, the gap formed between other adjacent wires is too small, the conductor cross section is less deformed, and the effect of suppressing deformation of the insulation coating is sufficiently obtained. I can't. On the other hand, if this relationship value exceeds 0.15, the gap formed between the other adjacent wires is too large, making the twisting operation difficult, and the workability deteriorates.

  The invention according to claim 3 is characterized in that the conductor cross section is configured to be easily deformable when inserted and fitted into the connector and connected by pressure welding. Provide non-halogen flame retardant wire.

  According to the non-halogen flame retardant electric wire for pressure welding according to the third aspect, since the conductor cross section is configured to be easily deformable, the above effect can be obtained with certainty.

  The invention according to claim 4 is configured such that the conductor cross-section can be easily deformed by moving other strands in a direction parallel to the conductor cross-section when being inserted and fitted into the connector and press-contact connected. The non-halogen flame retardant electric wire for pressure welding according to claim 3 is provided.

  According to the non-halogen flame retardant electric wire for pressure welding according to claim 4, the conductor cross-section can be easily obtained by moving the other wire in a direction parallel to the conductor cross-section using the gap formed between the other adjacent wires. Therefore, the above-described effects can be obtained with certainty.

  According to a fifth aspect of the present invention, there is provided a non-halogen flame retardant electric wire connection method for press contact, in which an insulation coating is provided on a conductor in which a plurality of strands are concentrically twisted, inserted into a connector, and press-connected. As the conductor, a conductor in which the outer diameter of the central strand is formed larger than the outer diameter of other strands around the central strand and a gap is formed between other adjacent strands is used. A method of connecting a non-halogen flame retardant electric wire for pressure welding characterized by the above.

  According to the connection method of the non-halogen flame retardant wire for pressure welding according to claim 5, the conductor is formed such that the outer diameter of the central strand is larger than the outer diameter of other strands around the central strand, and the other adjacent By using a conductor in which a gap is formed between these strands, the same effect as in the case of claim 1 can be obtained as a method for connecting a halogen-free flame retardant wire.

In the invention of claim 6, when the outer diameter of the central strand is R and the outer diameter of the other strand is R ₀ , the relationship value between the two expressed by the following formula is in the range of 0.05 to 0.15. The method for connecting a non-halogen flame retardant electric wire for pressure welding according to claim 5 is provided.

[Equation 2]
(R−R ₀ ) / R
According to the connection method of the non-halogen flame retardant electric wire for pressure welding according to claim 6, the above-mentioned effect can be obtained with certainty as the connection method of the non-halogen flame retardant electric wire.

  The invention of claim 7 is configured such that the conductor cross-section can be easily deformed by moving other strands in a direction parallel to the conductor cross-section when being inserted and fitted into the connector and press-contact connected. The connection method of the non-halogen flame retardant electric wire for pressure welding according to claim 5 or 6, characterized in that.

  According to the connection method of the non-halogen flame retardant electric wire for pressure welding according to claim 7, the above-mentioned effect can be surely obtained as the connection method of the non-halogen flame retardant electric wire.

  The present invention is limited to a case where a plurality of strands are concentrically twisted. However, when a plurality of strands are gathered and twisted, it is difficult to deform the conductor cross section due to the structure, and the present invention is applicable. Can not.

  According to the non-halogen flame retardant electric wire for pressure welding and its connection method of the present invention, in the end processing of the wire, the insulation force of the non-halogen wire is deformed by an external force applied when the wire is inserted and fitted into the connector and pressure-welded. Therefore, it is possible to eliminate the possibility of poor conduction by suppressing the decrease of the electric wire holding force by the connector and preventing the electric wire from easily coming out of the connector.

  A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

In FIG. 1, an insulating coating 4 is provided on a conductor 3 in which six other strands 2 are concentrically twisted around a central strand 1, inserted into a connector (not shown), and press-contacted for use. The non-halogen flame retardant electric wire 5 for pressure welding is shown. This conductor 3 structure of the electric wire 5 is called a six-way close-packed structure in which six strands are arranged around the central strand, and when all the strands are ordinary wires of the same diameter, external force is applied. On the other hand, it is the strongest structure that is difficult to deform. In this electric wire 5, the outer diameter of the central strand 1 is formed larger than the outer diameter of other strands 2 around the central strand 1, and a gap 6 is formed between other adjacent strands 2. ing. Regarding the degree of the gap 6, when the outer diameter of the central strand 1 is R and the outer diameter of the other strand 2 is R ₀ , the relationship value between the two expressed by the following equation is 0.05-0. It is comprised so that it may become the range of 15. If the relationship value between the two is in the range of 0.05 to 0.15, the cross section of the conductor is easily deformed by the external force applied when the wire is inserted and fitted into the connector and press-contacted in the end processing of the wire. The effect of suppressing the deformation of the insulating coating 4 due to the deformation of the conductor cross section can be sufficiently obtained.

[Equation 3]
(R−R ₀ ) / R
Incidentally, when this relational value is less than 0.05, as already described, the gap 6 formed between the other adjacent wires 2 is too small, and there is little deformation of the conductor cross section described above, and insulation The deformation suppressing effect of the coating 4 cannot be sufficiently obtained. On the other hand, if this relationship value exceeds 0.15, the gap 6 formed between other adjacent strands 2 is too large, making the twisting operation difficult, and the workability deteriorates.

  The insulating coating 4 is formed by extruding and covering a flame retardant non-halogen material on the conductor 3 in a ring shape. As this non-halogen material, for example, a polyolefin polymer such as polyethylene, ethylene-ethyl acrylate (EEA), or ethylene-vinyl acetate copolymer is used as a base polymer, and a metal hydroxide or the like mixed as a non-halogen flame retardant into these base polymers is used. Use.

  As the central strand 1 and other strands 2 shown in FIG. 1, the surface of a copper wire having a circular cross section is used, and the central strand 1 and the other strands 2 are concentrically twisted, A conductor 3 having a diameter of 0.48 mm is formed. On this conductor 3, a non-halogen flame retardant material in which 20 parts by weight of magnesium hydroxide is mixed with 100 parts by weight of low-density polyethylene having a density of 0.92 is extruded and coated, and an insulating coating 4 having an outer diameter of 0.88 ± 0.02 mm. Form. Evaluation of the pressure-weldability of the non-halogen flame-retardant electric wire thus manufactured was performed using an automatic pressure welding machine (AMP DN-J) manufactured by AMP and a connector with 15 poles (Mini-CT). The results are shown in Table 1.

  In Table 1, the evaluation of the pressure-weldability of the non-halogen flame retardant electric wire is based on FIG. 2, and the deformation of the insulating coating 4 seen when the non-halogen flame retardant electric wire 5 is driven between the strain reliefs 8 of the connector 7 is Even if one of the 15 poles extends out of the auxiliary line 9 of the strain relief 8, similarly, if the deformation of the insulating coating 4 falls within the auxiliary line 9 of the strain relief 7 in the same way, ○ It was.

  According to Table 1, in the case of the non-halogen flame retardant electric wires described in Examples 1 to 4, the conductor is effectively deformed, so that the deformation of the insulating coating is suppressed, and the press contact connectivity is good. confirmed. On the other hand, in the case of the non-halogen flame retardant electric wires described in Comparative Examples 1 to 3, it was confirmed that the conductor was hardly deformed, so that the insulation coating was greatly deformed and the press contact connectivity was inferior. Further, in the case of the non-halogen flame retardant electric wire of Comparative Example 4, the outer diameter of the central strand is formed larger than the outer diameter of the other strands, and the press contact connectivity is good. Is too large, making the twisting work difficult and confirming that workability is poor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view illustrating a structure of a non-halogen flame retardant electric wire according to an embodiment of the present invention. It concerns on one embodiment of this invention and is explanatory drawing which shows the condition when an electric wire is inserted and fitted to the connector.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Center strand 2 Other strand 3 Conductor 4 Insulation coating 5 Non-halogen flame retardant electric wire 6 Air gap 7 Connector 8 Strain relief 9 Auxiliary wire

Claims (7)

  In a non-halogen flame retardant wire for press contact, which is formed by providing an insulation coating on a conductor in which a plurality of strands are concentrically twisted, inserted into a connector, and press-connected, the outer diameter of the center strand is A non-halogen flame-retardant electric wire for pressure welding, wherein the non-halogen flame retardant electric wire is formed larger than the outer diameter of other strands around the wire and a gap is formed between other adjacent strands. When the outer diameter of the central strand is R and the outer diameter of the other strand is R ₀ , the relationship value between the two expressed by the following formula is in the range of 0.05 to 0.15. 2. The non-halogen flame retardant electric wire for pressure welding according to claim 1.
[Equation 1]
(R−R ₀ ) / R   The non-halogen flame retardant electric wire for press contact according to claim 1 or 2, wherein the conductor cross section is configured to be easily deformable when inserted and fitted into the connector and connected by press contact.   4. The conductor cross-section is configured to be easily deformable by moving another wire in a direction parallel to the conductor cross-section when inserted and fitted into the connector and press-fit. Non-halogen flame retardant wire for pressure welding as described in 1.   In the connection method of the non-halogen flame retardant wire for press contact, which is formed by providing an insulation coating on a conductor in which a plurality of strands are concentrically twisted, inserted into a connector, and press-connected, the center element is used as the conductor. Non-halogen for pressure welding, characterized in that the outer diameter of the wire is formed larger than the outer diameter of other strands around the central strand, and a conductor is used in which a gap is formed between other adjacent strands. How to connect flame retardant wires. When the outer diameter of the central strand is R and the outer diameter of the other strand is R ₀ , the relationship value between the two expressed by the following formula is in the range of 0.05 to 0.15. The connection method of the non-halogen flame-retardant electric wire for pressure welding according to claim 5.
[Equation 2]
(R−R ₀ ) / R   6. The conductor cross-section is configured to be easily deformable by moving another wire in a direction parallel to the conductor cross-section when inserted and fitted into the connector and press-fitted and connected. Or the connection method of the non-halogen flame-retardant electric wire for pressure welding of Claim 6.

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