JP5566772B2 - Conductor connection method and conductor connection structure - Google Patents

Description

  The present invention relates to a conductor connection method and a conductor connection structure.

  As a technique for connecting a conductor connector such as a terminal to a conductor such as a power cable or a power insulated wire, a technique using a compression connection and a technique using a crimp connection are known.

For compression connection, after inserting the conductor into the thick-walled hollow cylindrical connecting pipe part in the conductor connector, the connecting pipe part is sandwiched between a pair of hexagonal dies and compressed until the dies come into contact with each other to compress the connecting pipe part. It is a connection method for plastic working. According to this compression connection, the connecting pipe portion compressed by the hexagonal die is distorted toward the center, and the inner peripheral surface contracts in a similar manner while maintaining a circular shape. The conductor connector and the conductor are fixed in a state of being in close contact with each other. The compression connection is defined in, for example, the JIS standard (for example, see Non-Patent Document 1).
With this compression connection, the conductor connector and the conductor are firmly fixed and uniform, so that stable energization performance can be obtained. However, in order to compress the connecting pipe portion until the dies come into contact with each other, for example, a compressive force of 40 MPa is required, and a hydraulic press of 40 to 200 tons is required. Therefore, it is said that the construction of the compression connection is easy. hard.

As shown in FIG. 8, the crimping connection is performed so that the conductor 30 is inserted into the thin-walled / hollow cylindrical connecting tube portion 11 in the conductor connector 10, and then sandwiched with dies so that a part of the connecting tube portion 11 is crushed. This is a technique for fixing the conductor connector 10 and the conductor 30 by performing plastic working for forming a depression, causing the connecting pipe portion 11 to bite into the conductor 30 and crimping. The crimp connection is defined in, for example, the JIS standard (for example, see Non-Patent Documents 2 to 4).
In this crimping connection, it is not required to plastically deform the crimping connection part to a region where the dies come into contact with each other and cannot be further deformed, and it is allowed to complete the crimping process in the middle of plastic deformation. For example, in the case of an electric wire having a conductor size of 60 sqmm (mm ² ) or more, the tool manufacturer determines the height (crimp height) of the crimping portion from the reaction force of the crimping portion and the oil pressure limit value of the wire connecting tool. Connection processing is performed so that the height is less than or equal to the height (for example, see Non-Patent Document 4).
In such a crimping connection method, the crimp height tends to vary, and the connection strength and the reliability of the current-carrying performance may be inferior compared to the compression connection.
In addition, since the JIS standard for crimping connection is defined for a circular twisted wire conductor, when the conductor is a circular compression strand, if the crimping connection is made, the conductor strand is likely to break, and the conductor is a flexible twisted wire. In such a case, the close contact between the strands is likely to be insufficient, and even in these aspects, the crimp connection may be inferior in the connection strength and the reliability of the energization performance compared to the compression connection.

JIS C2804 “compression terminal” JIS C2805 "Crimping terminal for copper wire" JIS C2806 "Nude crimping sleeve for copper wire" JIS C9711 "Wire connection tool for indoor wiring"

By the way, in recent years, electric power facilities have also diversified, and there are cases in which power generation / transformation / transmission is operated outside of an electric power company. Examples include private cogeneration, solar systems, wind power generation, and biomass power generation. Both are facilities that secure energy for companies and local governments on a private profit basis.
Until now, facilities managed and operated by electric power companies have adopted highly reliable compression connection technology in order to achieve stable and high-current power transmission. Economically superior technology tends to be prioritized.
As a result, there have been attempts to use crimp terminals instead of compression terminals for the connection of large current cables such as the nominal cross-sectional area of conductors of 325 sqmm (mm ² ), which has been rarely used in the private sector, and compression connection even for crimp terminals. There is a demand for technology to connect as firmly as possible.

  An object of the present invention is to satisfactorily connect a conductor connector for crimp connection to a conductor.

In order to solve the above problems, one aspect of the present invention provides:
A conductor connection method for compressively connecting a conductor and a conductor connector for crimping connection having a connecting pipe portion into which the conductor is inserted , using a tubular member ,
The conductor connector includes a substantially flat terminal portion having an outer peripheral side plane continuous with the outer peripheral surface of the connection pipe portion, and the tubular member has an outer diameter 4/3 times the outer diameter of the connection pipe portion. Have
A tubular member for compression connection that covers the outer periphery of the connecting tube portion is attached to the outside of the connecting tube portion, and the conductor is inserted inside the connecting tube portion, and then the tubular member is formed into a hexagonal cross section at least twice. Comprising a compression step to compress ,
The compression step includes
A first compression process for sandwiching the tubular member in a direction inclined by 60 degrees with respect to the outer peripheral side plane, with a first hexagonal die having an outer diameter of the tubular member as a diagonal dimension of a regular hexagon;
And a second compression process of sandwiching the tubular member in a direction perpendicular to the outer peripheral side plane with a second hexagonal die having a diagonal dimension of a regular hexagon as the opposite dimension of the first hexagonal die. And

A tubular member for compression connection that can be attached to the outer periphery of the connection pipe part of the conductor connection tool for crimp connection is used, and the connection pipe part of the conductor connection tool is compressed to a hexagonal cross section several times. The surroundings can be compressed uniformly, and the conductor connector can be well compressed and connected to the conductor.
The order of attaching the tubular member to the outside of the connecting pipe part and inserting the conductor to the inside of the connecting pipe part may be any order.
Moreover, by making the outer diameter dimension of the tubular member 4/3 or less, it becomes possible to process into a shape that can be easily connected to a bus bar or the like with a small number of compression processes.
Further, for example, when the outer diameter dimension of the connection pipe portion of the conductor connector is designed to be “D” and the outer diameter dimension of the tubular member is “(4/3) × D”, the first compression treatment and the second compression treatment are performed. By performing the compression process, the outer diameter dimension (opposite side dimension) of the tubular member after the compression process can be reduced to “D”, and the compression connection portion can be compactly compressed to form a good conductor connection. .
Further, in the first compression process, the tubular member is compressed with a first hexagonal die in a direction inclined by 60 degrees with respect to the outer peripheral side plane of the terminal portion of the conductor connector, and on the outer peripheral side plane in the second compression process. By compressing the tubular member in the direction perpendicular to the second hexagonal die, the outer peripheral side plane of the terminal portion after compression connection and one of the six surfaces of the outer peripheral surface of the tubular member are substantially planes. Become one.
If one of the six surfaces of the outer peripheral surface of the tubular member is substantially flush with or recessed from the outer peripheral plane of the terminal portion after compression connection, the terminal portion is connected to an external conductor such as a bus bar, for example. When arranging and connecting, the tubular member does not interfere with the bus bar, and the outer peripheral side plane of the terminal portion can be brought into close contact with the bus bar to achieve a good conductor connection. And the connection part of the terminal part with respect to a bus bar can be made compact.

  Preferably, the tubular member is made of a material having a larger coefficient of thermal expansion than the conductor connector.

  If the tubular member is a material having a coefficient of thermal expansion greater than that of the conductor connector, the tubular member and the conductor are connected even when the tubular member and the conductor connector formed by compression connection repeatedly generate heat upon energization and subsequent cooling. The problem that a gap is generated at the interface with the connector is unlikely to occur, and product stability is maintained.

Another aspect of the present invention is as follows:
A conductor connector for crimping connection having a conductor of a cable, a connecting pipe part into which the conductor is inserted, and a substantially flat terminal part having an outer peripheral side plane continuous from the outer peripheral surface of the connecting pipe part, and the connecting pipe part A compression connecting tubular member mounted on the outside of
From the periphery of the tubular member having an outer diameter 4/3 times the outer diameter of the connecting pipe portion, a first hexagonal die having a diagonal dimension of a regular hexagon as the outer diameter of the tubular member is formed on the outer peripheral side plane. After sandwiching the tubular member in a direction inclined by 60 degrees, a second hexagonal die having the opposite side dimension of the first hexagonal die as a diagonal dimension of a regular hexagon, and the tubular member in a direction perpendicular to the outer peripheral side plane A conductor connection structure characterized by sandwiching a member and compressing the tubular member and the connection pipe portion into a regular hexagon, and one surface of the regular hexagon is substantially flush with an outer peripheral side plane of the terminal portion. Is the body.

In this conductor connection structure, since the compression connection tubular member is put on the outer periphery of the connection pipe portion of the conductor connection tool for crimp connection, the conductor connection tool for crimp connection is electrically connected to the conductor. Can be connected well.
In addition, since one of the six surfaces of the outer peripheral surface of the tubular member is deeper than the outer peripheral side plane of the terminal portion after compression connection, the terminal is connected to an external conductor such as a bus bar, for example. When the portion is disposed and connected, the tubular member does not interfere with the bus bar, so that the outer peripheral side plane of the terminal portion can be connected in close contact with the bus bar. And the connection part of the terminal part with respect to a bus bar can be made compact.

According to the present invention, by using a tubular member for compression connection that can be mounted on the outer periphery of the connection pipe portion of the conductor connection tool for crimping connection, the connection pipe portion of the conductor connection tool is connected to the cable in the entire circumferential direction. It can be crimped (contacted) to the conductor, and the conductor connector and the conductor can be securely connected both electrically and mechanically.
For example, when the outer diameter of the tubular member is set to 4/3 times or less than the outer diameter of the connecting pipe portion, it can be processed into a shape that can be easily connected to a bus bar or the like with a small number of compression processes. .

It is a top view which shows the crimp terminal and compression collar which comprise a part of conductor connection structure. FIG. 2A is a plan view showing a state where the compression collar is assembled to the crimp terminal, FIG. 2A is a cross-sectional view taken along the line bb in FIG. 2A, and FIG. It is a figure (c). It is explanatory drawing which shows the arrangement | positioning which connects the conductor which comprises a conductor connection structure, a crimp terminal, and a compression collar in cross section. It is explanatory drawing which shows the 1st compression process in a compression process. It is explanatory drawing which shows the 2nd compression process in a compression process. It is explanatory drawing which shows the conductor connection structure formed by compressing and connecting a conductor, a crimp terminal, and the compression collar. It is a table | surface which shows the measured value (calculated value) of the compressibility in various conductor connection structures. It is explanatory drawing which shows the conventional crimping connection.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. However, the embodiments described below are given various technically preferable limitations for carrying out the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

  FIG. 1 is a plan view showing a crimp terminal and a compression collar forming a part of the conductor connection structure. 2A, 2B, and 2C are explanatory views showing a state in which a compression collar is assembled to a crimp terminal. FIG. 3 is an explanatory view showing an arrangement for connecting a conductor, a crimp terminal, and a compression collar constituting the conductor connection structure.

As shown in FIGS. 1 to 3, the crimp terminal 10 includes a connection pipe part 11 into which the conductor 30 is inserted and a terminal part 12 integrally formed with the connection pipe part 11. It is.
The connecting pipe portion 11 has a substantially cylindrical shape, and has an insertion hole 11 a that houses a conductor 30 of a cable or an electric wire.
The terminal portion 12 has a substantially flat plate shape and has an outer peripheral side plane 13 that is continuous with the outer peripheral surface of the connecting pipe portion 11. Moreover, the terminal part 12 has the circular small hole 14 formed in the approximate center side.

The crimp terminal 10 conforms to the standard of JIS C2805 “Copper Wire Crimp Terminal”, and the thin-walled tubular connecting pipe portion 11 has a relatively large size of, for example, 100 to 325 sqmm (mm ² ).
The crimp terminal 10 is made of, for example, an oxygen-free copper plate conforming to the standard of JIS H3100 C1020P. An oxygen-free copper plate is excellent in electrical conductivity (conductivity) among copper and is excellent in extensibility for processing, and is therefore suitable as a material for a conductor connector (crimp terminal 10). In particular, brazing is performed to form a thin-walled cylindrical connecting pipe portion 11 by forming a copper plate, and therefore, it is appropriately annealed to increase the spreadability. Therefore, it is extremely suitable as a material for a conductor connector for crimping connection.
The crimp terminal 10 may be a commercially available ready-made product.

As shown in FIGS. 1 to 3, the compression collar 20 has a substantially cylindrical shape, and is a compression connection tubular member having an insertion hole 20 a that houses the connection tube portion 11 of the crimp terminal 10. is there. The compression collar 20 is a thick cylindrical body having substantially the same length as that of the connecting pipe portion 11, and has tapered portions 21 and 21 whose outer diameters become smaller toward the end portions at both ends thereof. .
The inner diameter dimension of the compression collar 20 corresponds to the outer diameter dimension of the connecting tube portion 11, and the connecting tube portion 11 of the crimp terminal 10 is as small as possible regardless of whether the crimp terminal 10 is an off-the-shelf product. The size is such that the compression collar 20 can be properly inserted to the outer periphery of the connecting pipe portion 11 without being inserted.
In particular, the outer diameter of the compression collar 20 is not less than 7/6 times (about 1.17 times) and not more than 4/3 times (about 1.33 times) the outer diameter of the connecting pipe portion 11 of the crimp terminal 10. It is preferable.
In this embodiment, when the outer diameter of the connecting pipe portion 11 is “D”, the compression collar 20 has an outer diameter of “(4/3) × D” that is 4/3 times that. . The outer diameter of the compression collar 20 referred to here is the maximum outer diameter dimension corresponding to the thickest part of the compression collar 20.

  The compression collar 20 is made of, for example, C2600 brass (7.3 brass) defined in JIS H3250 “Copper and copper alloy rod”. Thus, the compression collar 20 is made of a material (brass) having a larger thermal expansion coefficient than that of the copper crimp terminal 10.

  Next, a conductor connection method for compressing and connecting the conductor 30 and the crimp terminal 10 using the compression collar 20 will be described.

First, as shown in FIG. 3, the conductor 30 is inserted inside the connection tube portion 11 in the crimp terminal 10, and the compression collar 20 is attached to the outside of the connection tube portion 11.
As described above, the outer diameter of the connecting tube portion 11 of the crimp terminal 10 is “D”, and the outer diameter of the compression collar 20 is “(4/3) × D”.
In addition, the conductor 30 peels off the insulation layer of a cable or an electric wire, and the center conductor is exposed, This conductor 30 is a circular twisted conductor formed by twisting together several conductor strands.

Next, as shown in FIG. 4, the compression collar 20 attached to the connecting tube portion 11 of the crimp terminal 10 is the outer diameter “(4/3) × D” of the compression collar 20 and is a regular hexagonal diagonal dimension. A first compression process is performed in which the first hexagonal die 50 is sandwiched and compressed. The first hexagonal die 50 is composed of a pair of dice 51 and 51 divided into two at regular hexagonal corners.
In this first compression treatment, the compression collar 20 is sandwiched between a pair of dies 51, 51 from a direction inclined by 60 degrees with respect to the outer peripheral side plane 13 of the terminal portion 12 of the crimp terminal 10, and in the direction inclined by 60 degrees. The compression collar 20 is compressed with a first hexagonal die 50.
In FIG. 4, the dies 51, 51 are drawn at an angle, but the outer peripheral side plane 13 of the terminal portion 12 may be tilted so that the compression direction of the dies 51, 51 is vertical.
Thus, by the first compression process, the compression collar 20 is compressed into a regular hexagonal cross section having a diagonal dimension of “(4/3) × D” and an opposite dimension of “(2/3) × √3 × D”. Has been.
Here, the opposite side dimension “(2/3) × √3 × D” of the compression collar 20 after the first compression processing is √3 / 2 times the diagonal dimension “(4/3) × D”. It has become. This is because the compression collar 20 having an outer diameter of “(4/3) × D” is compression-deformed into a regular hexagon with a first hexagonal die 50 having a diagonal dimension of “(4/3) × D”. It depends.

Next, as shown in FIG. 5, the compression collar 20 portion after the first compression processing is set so that the opposite side dimension “(2/3) × √3 × D” of the first hexagonal die 50 is a regular hexagonal diagonal dimension. A second compression process is performed in which the second hexagonal die 60 is inserted and compressed. In addition, the 2nd hexagon die 60 consists of a pair of dice | dies 61 and 61 divided into 2 by the corner | angular part of the regular hexagon.
In the second compression process, the compression collar 20 is sandwiched between a pair of dies 61 and 61 in a direction perpendicular to the outer peripheral side plane 13 of the terminal portion 12 of the crimp terminal 10, and the compression collar 20 is inserted in the vertical direction. Is compressed with a second hexagonal die 60.
Thus, by the second compression process, the compression collar 20 is compressed into a regular hexagonal cross section having a diagonal dimension of “(2/3) × √3 × D” and an opposite side dimension of “D”.
Here, the opposite side dimension “D” of the compression collar 20 after the second compression processing is √3 / 2 times the diagonal dimension “(2/3) × √3 × D”. This is because the compression hexagon 20 whose opposite dimension of the regular hexagon is “(2/3) × √3 × D” is the second hexagon whose diagonal dimension is “(2/3) × √3 × D”. This is because the die 60 is compressed into a regular hexagon.

Then, as shown in FIGS. 5 and 6, the compression collar 20 is subjected to a compression process in which a first compression process and a second compression process are performed, and the conductor 30 is pressure-bonded using the compression collar 20. The conductor connection structure 100 in which the terminals 10 are compression-connected can be formed.
As described above, by using the compression collar 20, the connection tube portion 11 of the crimp terminal 10 can be uniformly compressed around the conductor 30, and the crimp terminal 10 can be compressed and connected to the conductor 30 in a favorable manner. .

As shown in FIG. 6, one of the six surfaces forming the outer peripheral surface of the compression collar 20 in the conductor connection structure 100 coincides with the outer peripheral side plane 13 of the terminal portion 12 of the crimp terminal 10.
This is because two regular hexagonal compression processes (first compression process and second compression process) are performed on the compression collar 20 whose outer diameter dimension is “(4/3) × D” shown in FIG. The outer diameter of the compression collar 20 is compressed twice to √3 / 2 and reduced to 3/4 times (√3 / 2) × (√3 / 2), and the opposite side dimension of the compression collar 20 is reduced. This is because it was reduced to “D”.
That is, the outer diameter of the compression collar 20 is designed to be 4/3 times the outer diameter “D” of the connecting pipe portion 11 in advance, so that it continues to the outer peripheral surface of the original connecting pipe portion 11. The outer peripheral side plane 13 of the terminal portion 12 in the arrangement is substantially flush with a part of the outer peripheral surface of the compression collar 20 after compression processing (one of the six surfaces).
Thus, if the outer peripheral side plane 13 of the terminal part 12 in the conductor connection structure 100 and the outer peripheral surface (one of the six surfaces) of the compression collar 20 are substantially flush, the conductor connection structure When connecting the 100 terminal portions 12 to, for example, a bus bar, the outer peripheral side plane 13 of the terminal portion 12 can be screwed in close contact with the bus bar without the compression collar 20 portion interfering with the bus bar. Become.

The length dimension of the first hexagonal die 50 used for the first compression process in the compression process and the second hexagonal die 60 used for the second compression process along the axial direction of the conductor 30 is a compression collar. The size is equal to or larger than the length dimension of 20 and enables compression processing in close contact with the entire outer periphery of the compression collar 20.
Since both end portions of the compression collar 20 have taper portions 21, the contact pressure due to the compression process becomes weaker toward the end portion of the compression collar 20, so that the end opening of the compression collar 20 (connecting tube portion 11) is opened. The nearby conductor 30 is only slightly pressurized, and the conductor 30 is hardly compressed.
Since the compression collar 20 having the taper portion 21 compresses the connection pipe portion 11 with respect to the conductor 30 relatively gently, the edge of the opening of the compression collar 20 (connection pipe portion 11) is the conductor. 30 is not pressed. The wire of the conductor 30 is not cut by the compression of the compression collar 20, and the conductor 30 in the conductor connection structure 100 is prevented from being disconnected.

  Next, a preferable outer diameter dimension of the compression collar 20 used when the conductor 30 and the crimp terminal 10 are compression-connected will be described.

The compression ratio is used as an evaluation standard for the degree of compression in the compression connection, and the compression ratio of the conductor cross-sectional area is 6% or more, which is a condition for forming a strong compression connection and obtaining a stable long-term conduction characteristic. It has been known. For example, JIS C2804 “compression terminal” satisfies a compression rate of 6% or more.
The compression rate here is the change rate (decrease rate) of the cross-sectional area obtained by reducing the sum of the cross-sectional areas of the connecting pipe portion 11 before compression processing and the conductor 30 inserted into the connecting pipe portion 11 after the compression processing. It is. In addition, the state where the gap between the conductor strands of the conductor 30 and the gap between the inner diameter of the connecting pipe portion 11 and the outer diameter of the conductor 30 is filled by compression processing, and the cross-sectional area of the conductor 30 and the connecting pipe portion 11 is not changed. The compression rate is 0%. Moreover, if the compression rate is a negative numerical value, it can be said that the state before these gaps are filled.

The compression ratio table relating to the conductor connection structure shown in FIG. 7 is a correspondence relationship between the crimp terminals 10 (connection pipe portions 11) of various sizes, the conductors 30 of various sizes, and the compression collars 20 of various sizes, and combinations thereof. It is the result of investigating the correspondence with the compression rate in the conductor connection structure 100 compressed and connected. From this table, as long as the outer diameter magnification of the compression collar 20 with respect to the outer diameter of the crimp terminal 10 (connecting tube portion 11) is 7/6 times (about 1.17 times) or more, the compression ratio is any size. It can be seen that 6% is satisfied.
Further, when the opposite side dimension of the compression collar 20 after the second compression process in the compression process is a value exceeding the outer diameter dimension of the crimp terminal 10, the outer peripheral side plane 13 of the terminal portion 12 in the conductor connection structure 100 and There is a problem that the outer peripheral surface (one of the six surfaces) of the compression collar 20 is not substantially flush. Therefore, the opposite side dimension of the compression collar 20 after the second compression process is such that the outer peripheral surface (one of the six surfaces) of the compression collar 20 does not protrude from the outer peripheral side plane 13 of the terminal portion 12. In order to satisfy that the outer diameter of the crimp terminal 10 is smaller than the outer diameter, the outer diameter magnification of the compression collar 20 with respect to the outer diameter of the crimp terminal 10 (connection tube portion 11) is 4/3 times as described above. Must be less than (approximately 1.33 times). As can be seen from the compression ratio table for the conductor connection structure shown in FIG. 7, the compression collar 20 up to an outer diameter magnification of 4/3 times (about 1.33 times) has a good compression ratio after the second compression treatment. The value is shown.

  In this way, the outer diameter of the compression collar 20 is 7/6 times (about 1.17 times) or more and 4/3 times (about 1.33 times) or less of the outer diameter of the connecting tube portion 11 of the crimp terminal 10. By doing so, it is possible to form a conductor connection structure 100 having a strong compression connection satisfying a compression ratio of 6% or more and having a stable long-term conduction characteristic.

  Next, the material will be considered. When the material of the crimp terminal 10 used for the conductor connection structure 100 is oxygen-free copper or tough pitch copper, the material of the compression collar 20 is preferably brass. The reason will be described below.

  When forming the conductor connection structure 100, the compression collar 20 and the crimp terminal 10 (connection pipe part 11) are attached to the connection pipe part 11 and subjected to two regular hexagonal compression treatments. However, the metal atoms are simply compressed and no intermetallic bonds are formed, so that they can be separated when disassembled.

When the conductor connection structure 100 is connected to an external conductor (for example, a bus bar) to conduct current, the current flows from the conductor 30 to the connecting tube portion 11 and the terminal portion 12, and the external conductor (to which the terminal portion 12 is connected) ( Flows to (Busper). At this time, the current is diverted to the compression collar 20 to some extent, but the current is very small, and the compression collar 20 does not generate heat when energized. Rather, the compression collar 20 effectively functions as a heat dissipation element. Under such circumstances, the temperature of the compression collar 20 is lower than that of the connecting pipe portion 11.
When the connecting pipe portion 11 that has generated heat due to energization is thermally expanded, the adhesion to the compression collar 20 is increased. Since the thermal expansion of the connecting pipe portion 11 is limited by the compression collar 20, the connecting tube portion 11 expands in the axial direction because it cannot expand in the outer diameter direction. Although it seems that there is no inconvenience at first glance, the outer diameter of the connecting pipe portion 11 that is elongated in the axial direction is maintained even after the temperature is lowered, and the interface between the connecting pipe portion 11 and the compression collar 20 is cooled after cooling. It becomes easy to produce a gap in.
Thus, when the temperature rise and fall are repeated, a gap is formed at the interface between the connecting pipe portion 11 and the compression collar 20 that are in close contact with each other, and there is a concern about adverse effects such as corrosion caused by moisture entering the gap. The
This is the first situation (situation relating to thermal expansion) in which brass is selected as the material of the compression collar 20.

The compression collar 20 is preferably made of a nonmagnetic material.
Since the compression collar 20 wraps the conductor 30 in a circle, if the compression collar 20 is made of a magnetic material, heat is generated due to induction by current conduction. If the heat generated by the compression collar 20 causes the temperature of the crimping terminal 10 to rise, it causes power loss.
For example, since austenitic stainless steel is a material with extremely weak magnetism, it has a track record of use where induction can occur. Not suitable for 20 materials.
This is the second situation (the situation as a non-magnetic material) in which brass is selected as the material of the compression collar 20.

In consideration of such circumstances, C2600 brass (7.3 brass) specified in JIS H3250 “Copper and copper alloy rod” is used as the material of the compression collar 20.
When the material of the compression collar 20 is brass, there are the following merits.
(1) The thermal expansion coefficient of brass is 20 × 10 ⁻⁶ / ° C., which is larger than the oxygen-free copper or tough pitch copper of the crimp terminal 10, so that there is a gap at the interface between the connecting pipe portion 11 and the compression collar 20 due to thermal expansion. There is no fear of it occurring.
(2) Brass is an alloy containing 70% copper, and since the potential gradient of oxygen-free copper and tough pitch copper of the crimp terminal 10 is substantially the same, moisture adheres to the connecting pipe portion 11 and the compression collar 20. There is no risk of electric corrosion.
(3) Since brass is excellent in cold workability (expandability), there is no fear of breakage or the like during compression processing.
(4) Since brass is a general-purpose copper alloy, it is easily available and is cheaper than copper.
(5) The electrical conductivity (conductivity) of brass is as low as 28 with copper as 100, but the compression collar 20 does not bear the current-carrying function, so there is no need to consider it as a problem.
(6) Brass is a complete non-magnetic material.
These eight items are the reasons for selecting brass as the material of the compression collar 20.

As described above, by using the compression collar 20 for the conductor connection structure 100, the connection tube portion 11 of the crimp terminal 10 can be uniformly compressed around the conductor 30, and the crimp terminal 10 is good for the conductor 30. Can be compressed and connected.
In particular, the outer diameter of the compression collar 20 is 7/6 times (about 1.17 times) or more and 4/3 times (about 1.33 times) or less of the outer diameter of the connecting pipe portion 11 of the crimp terminal 10. By doing so, it is possible to form a strong connection that satisfies a compression ratio of 6% or more, and to form the conductor connection structure 100 having stable long-term current-carrying characteristics, and a shape that can be easily connected with a small number of compression processes. In other words, it is possible to process into a shape that can be connected to a bus bar or the like with a screw. That is, by using the compression collar 20 having an outer diameter in this range, a connection structure having good electrical and mechanical connectivity can be obtained.

As described above, the thick cylindrical compression collar 20 is attached to the connecting pipe portion 11 of the crimp terminal 10 defined by JIS C2805 “Copper wire crimp terminal” and JIS C2806 “Copper wire bare crimp sleeve”. It was installed to enable conductor connection equivalent to the hexagonal compression connection specified in JIS C2804 “compression terminal”.
For example, when a crimping connection is made to a large conductor exceeding 100 sqmm (mm ² ), especially 150 sqmm (mm ² ) by the conventional crimping connection method, the conductor wire is broken, the contact pressure is insufficient, the influence of crimping tool error, etc. However, by applying the compression collar 20, even if the crimp terminal 10 for crimp connection is used, the conductor connection having high reliability obtained by the compression connection is required. Made possible.
The conductor connection method according to the present invention can be said to be a technique relating to conductor connection particularly effective for a large conductor exceeding 100 sqmm (mm ² ).

  In the above embodiment, the compression collar 20 is attached to the crimp terminal 10 and they are compression-connected. However, the present invention is not limited to this, and the compression collar is crimped in advance. The conductor connector having a shape attached to the terminal may be formed by forging or casting. By doing so, it is possible to save the effort of mounting the compression collar and to eliminate the gap between the compression collar and the crimp terminal and to improve the connectivity.

  In addition, it is needless to say that other specific detailed structures can be appropriately changed.

10 Crimp terminal (conductor connector)
DESCRIPTION OF SYMBOLS 11 Connection pipe part 11a Insertion hole 12 Terminal part 13 Outer peripheral side plane 20 Collar for compression (tubular member)
20a Insertion hole 21 Tapered portion 30 Conductor 50 First hexagon die 60 Second hexagon die 100 Conductor connection structure

Claims (3)

A conductor connection method for compressively connecting a conductor and a conductor connector for crimping connection having a connecting pipe portion into which the conductor is inserted , using a tubular member ,
The conductor connector includes a substantially flat terminal portion having an outer peripheral side plane continuous with the outer peripheral surface of the connection pipe portion, and the tubular member has an outer diameter 4/3 times the outer diameter of the connection pipe portion. Have
A tubular member for compression connection that covers the outer periphery of the connecting tube portion is attached to the outside of the connecting tube portion, and the conductor is inserted inside the connecting tube portion, and then the tubular member is formed into a hexagonal cross section at least twice. Comprising a compression step to compress ,
The compression step includes
A first compression process for sandwiching the tubular member in a direction inclined by 60 degrees with respect to the outer peripheral side plane, with a first hexagonal die having an outer diameter of the tubular member as a diagonal dimension of a regular hexagon;
And a second compression process of sandwiching the tubular member in a direction perpendicular to the outer peripheral side plane with a second hexagonal die having a diagonal dimension of a regular hexagon as the opposite dimension of the first hexagonal die. Conductor connection method. The conductor connection method according to claim 1 , wherein the tubular member is made of a material having a thermal expansion coefficient larger than that of the conductor connector. A conductor connector for crimping connection having a conductor of a cable, a connecting pipe part into which the conductor is inserted, and a substantially flat terminal part having an outer peripheral side plane continuous from the outer peripheral surface of the connecting pipe part, and the connecting pipe part A compression connecting tubular member mounted on the outside of
From the periphery of the tubular member having an outer diameter 4/3 times the outer diameter of the connecting pipe portion, a first hexagonal die having a diagonal dimension of a regular hexagon as the outer diameter of the tubular member is formed on the outer peripheral side plane. After sandwiching the tubular member in a direction inclined by 60 degrees, a second hexagonal die having the opposite side dimension of the first hexagonal die as a diagonal dimension of a regular hexagon, and the tubular member in a direction perpendicular to the outer peripheral side plane A conductor connection structure characterized by sandwiching a member and compressing the tubular member and the connection pipe portion into a regular hexagon, and one surface of the regular hexagon is substantially flush with an outer peripheral side plane of the terminal portion. body.

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