JP2015153688A - connection terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection terminal in which contact resistance can be reduced with a simple structure. while suppressing up-sizing.SOLUTION: In a connection terminal 1 including an elastic piece 7 having a biasing force toward the connection of a mating terminal, and a contact 9 projecting from the elastic piece 7 toward the connection side of a mating terminal, and is brought into contact with the surface of the connection of a mating terminal by the biasing force of the elastic piece 7, the contact 9 is formed in semi-cylindrical shape along the width direction of the elastic piece 7, and the central portion of the elastic piece 7 in the length direction has a groove-like hollow section 11 projecting in a direction separating from the connection of a mating terminal, and strip contact parts 13, 13 formed on the opposite sides of the hollow section 11 in the length direction of the elastic piece 7.

Description

  The present invention relates to a connection terminal. Specifically, the present invention relates to a female connection terminal having a contact portion provided on an elastically deformable elastic piece connected to a tab-shaped connection portion of a male terminal.

  Conventionally, as a connection terminal, an elastic piece having an urging force toward the connection portion of the mating terminal, and a connection portion of the mating terminal projecting from the elastic piece toward the connection portion side of the mating terminal by the urging force of the elastic piece There is known a device provided with a contact portion that is brought into contact with the surface of the material (for example, see Patent Document 1).

  In this connection terminal, the connection portion of the mating terminal is formed in a tab shape, and the elastic piece is provided in the box-shaped main body portion. By inserting the connection portion of the mating terminal into the main body portion, the contact portion is elastic piece. Due to the urging force, the mating terminal is brought into contact with the connecting portion of the mating terminal, and the mating terminal and the connecting terminal are electrically connected.

JP 2008-210755 A

  By the way, in the connection terminal like the said patent document 1, in order to reduce the contact resistance of a contact part and the connection part of a counterpart terminal, it is effective to enlarge the contact area of the contact part with respect to the connection part of a counterpart terminal. It was supposed to be.

  In order to increase the contact area of the contact portion, it is conceivable to improve the contact load of the contact portion with respect to the connection portion of the mating terminal, or to enlarge the contact portion. However, an urging force is applied to the elastic piece. It was necessary to make the spring structure complicated and to increase the size of the connection terminal.

  In view of this, an object of the present invention is to provide a connection terminal capable of suppressing the increase in size and reducing the contact resistance with a simple structure.

  Here, the present inventor has found that the current flowing through the contact portion does not flow on the average with respect to the contact area, but there are places where the current easily flows and places where it is difficult to flow. In particular, it has been found that the current flowing through the contact portion concentrates on the outer peripheral portion in contact when the contact portion has a single circular shape. Therefore, the present invention is characterized by the following configuration.

  The invention according to claim 1 is an elastic piece having an urging force toward the connection portion of the mating terminal, and projects from the elastic piece toward the connection portion side of the mating terminal and is urged by the urging force of the elastic piece. A contact terminal that is in contact with the surface of the connection part of the terminal, wherein the contact part is formed in a semi-cylindrical shape along the width direction of the elastic piece, and the length direction of the elastic piece A groove-shaped hollow portion projecting in a direction away from the connection portion of the mating terminal, and strip-shaped contact portions formed on both sides of the length of the elastic piece of the hollow portion, respectively It is characterized by having.

  In this connection terminal, the contact portion is formed in a semi-cylindrical shape along the width direction of the elastic piece, and the groove in which the central portion in the length direction of the elastic piece protrudes in a direction away from the connection portion of the mating terminal. A hollow portion and strip-shaped contact portions formed on both sides of the elastic piece in the length direction of the hollow portion, so that the contact portion is prevented from being enlarged and spaced apart through the hollow portion. It is possible to facilitate the flow of current through the contacted portion.

  For this reason, while not complicating the spring structure which gives urging | biasing force to an elastic piece, the contact resistance of a contact part and the connection part of an other party terminal can be reduced, without enlarging a connection terminal. .

  Therefore, in such a connection terminal, since the contact portion has a hollow portion and a contact portion with a simple structure, an increase in size can be suppressed and a contact resistance can be reduced with a simple structure.

  According to the present invention, it is possible to provide a connection terminal that can suppress an increase in size and can reduce contact resistance with a simple structure.

It is sectional drawing of the connecting terminal which concerns on embodiment of this invention. (A) is a perspective view of the elastic piece of the connection terminal which concerns on embodiment of this invention. FIG. 2B is a side view of FIG. (A) is sectional drawing of the contact part of the connecting terminal which concerns on embodiment of this invention. FIG. 3B is a front view of FIG. (A) is sectional drawing of the contact part of a prior art example. FIG. 4B is a front view of FIG. It is a schematic diagram which shows the numerical value of Formula 1. It is a schematic diagram when a contact part is made into a square. It is a figure which shows the change of the electrical conductivity ratio with respect to thickness ratio t / L of a contact part.

  A connection terminal according to an embodiment of the present invention will be described with reference to FIGS.

  The connection terminal 1 according to the present embodiment is elastically provided with an elastic piece 7 having a biasing force toward the connection portion 5 of the mating terminal 3 and protruding from the elastic piece 7 toward the connection portion 5 side of the mating terminal 3. And a contact portion 9 that is brought into contact with the surface of the connection portion 5 of the mating terminal 3 by the biasing force of the piece 7.

  The contact portion 9 is formed in a semi-cylindrical shape along the width direction of the elastic piece 7, and the center portion in the length direction of the elastic piece 7 is provided so as to project away from the connection portion 5 of the mating terminal 3. The groove-shaped hollow portion 11 and strip-shaped contact portions 13, 13 formed on both sides of the elastic piece 7 in the length direction of the hollow portion 11, respectively.

  As shown in FIGS. 1 to 3, the connection terminal 1 is a female terminal having a box-shaped electrical connection portion 15, and is a terminal portion of an electric wire (not shown) connected to a power source or equipment, or a power source or the like. It is electrically connected to a circuit board (not shown) or the like arranged in the device.

  In the electrical connection portion 15 of the connection terminal 1, the connection portion 5 of the mating terminal 3, which is a male terminal having a tab-like connection portion 5 connected to a power source or a device as in the connection terminal 1, is inserted, The connection terminal 1 and the counterpart terminal 3 are electrically connected. An elastic piece 7 is provided in the electrical connection portion 15 of the connection terminal 1.

  The elastic piece 7 is provided by bending the upper wall portion of the electrical connection portion 15 toward the inner side. The elastic piece 7 has a predetermined biasing force toward the connection portion 5 side of the counterpart terminal 3 with respect to the connection portion 5 of the counterpart terminal 3 inserted into the electrical connection portion 15.

  Such an elastic piece 7 is provided with a contact portion 9, and by inserting the connection portion 5 of the mating terminal 3 into the electrical connection portion 15, the contact portion 9 is directed toward the connection portion 5 of the mating terminal 3. The contact portion 9 and the connection portion 5 of the mating terminal 3 are brought into contact with each other by energizing the contact load.

  The contact portion 9 is formed so that the central portion in the width direction of the elastic piece 7 faces the connection portion 5 side of the mating terminal 3 inserted into the electric connection portion 15 (the lower wall portion side of the electric connection portion 15). And projecting in a semicircular shape in a side view, and has a groove-like hollow portion 11 and strip-shaped contact portions 13 and 13.

  The hollow portion 11 has a width of the elastic piece 7 with the center portion in the length direction of the semi-cylindrical contact portion 9 facing away from the connection portion 5 of the mating terminal 3 (in the direction of the upper wall portion of the electrical connection portion 15). It protrudes along the direction and is formed in a groove shape so that the surface of the mating terminal 3 on the connection portion 5 side is hollow. Both side portions of the hollow portion 11 in the length direction of the elastic piece 7 are band-shaped contact portions 13 and 13, respectively.

  The contact portions 13 and 13 are formed on the surface of the mating terminal 3 on the connection portion 5 side, are both side portions in the length direction of the elastic piece 7 of the hollow portion 11, and are formed in a band shape. The contact portions 13 and 13 are brought into contact with the surface of the connection portion 5 of the mating terminal 3 inserted into the electrical connection portion 15 by the urging force of the elastic piece 7, and the connection terminal 1 and the mating terminal 3 are electrically connected. Connect.

  Here, the contact resistance can be obtained by the following theoretical formula.

Rc = (ρ / D) + (ρ / 2na)
Here, Rc is the contact resistance, ρ is the volume resistivity of the metal, D is the apparent contact surface diameter, 2a is the true contact surface diameter, and n is the true contact, as shown in FIG. The number of faces.

  As is clear from this theoretical formula, in order to lower the contact resistance (Rc), at least one of the apparent contact surface diameter (D), the true contact surface diameter (2a), and the number of the true contact surfaces (n) is required. One needs to be larger.

  For this reason, it is very difficult to accurately design the true contact surface diameter (2a) and the number of true contact surfaces (n), so the apparent contact surface diameter (D) is increased. It is effective to design as follows.

  Therefore, as shown in FIGS. 3 and 4, the distance to the outer diameter of each of the contact portions 13 and 13 in the contact portion 9, that is, the apparent contact surface diameter D <b> 1 is the same as that of the conventional hollow portion 11 or contact portion. 13 and 13 is set larger than the apparent contact surface diameter D2 which is the outer diameter (length) of the contact portion 13a in the semi-cylindrical contact portion 9a.

  On the other hand, in order to verify the current flow in the contact portion 9, the behavior of the concentrated resistance (conductivity ratio) with respect to the apparent contact area was verified using a model as shown in FIG.

  The result is shown in FIG. The horizontal axis is the value obtained by dividing the width t of the energized region by the length L from the center of the contact point to the outer diameter, and the vertical axis is the conductivity ratio with the contact resistance when the entire surface is the energized region ( Reciprocal of contact resistance ratio).

  As is apparent from FIG. 7, about 90% of the entire contact resistance is defined in the contact region of about 20% from the outer periphery of the contact portion. For this reason, it turns out that the electric current which flows through a contact part flows predominantly in the outer peripheral part of a contact part.

  Therefore, the actual current flows only in a small part like the outer peripheral part that easily flows, and even if the contact area of the contact portion 9 is increased unnecessarily, it is not very effective.

  For this reason, in the contact portion 9 of the connection terminal 1, the apparent contact surface diameter D is obtained by making the both side portions in the length direction of the elastic piece 7, which is the outer peripheral portion of the hollow portion 11, into contact portions 13 and 13. Can be increased, current can be easily passed through the contact portions 13, 13, and the contact resistance between the contact portion 9 and the connection portion 5 of the mating terminal 3 can be reduced. In addition, the contact portion 9 does not become unnecessarily large, and the enlargement of the connection terminal 1 can be suppressed.

  In such a connection terminal 1, the contact portion 9 is formed in a semi-cylindrical shape along the width direction of the elastic piece 7, and the central portion in the length direction of the elastic piece 7 is away from the connection portion 5 of the mating terminal 3. Groove-shaped hollow portion 11 projecting toward the surface and strip-shaped contact portions 13, 13 formed on both sides of the elastic piece 7 in the length direction of the hollow portion 11, respectively. The current can be easily passed through the contact portions 13 and 13 that are spaced apart via the hollow portion 11 while suppressing the increase in size.

  For this reason, while not complicating the spring structure which gives urging | biasing force to the elastic piece 7, contact resistance of the contact part 9 and the connection part 5 of the other party terminal 3 is made without enlarging the connection terminal 1. Can be reduced.

  Therefore, in such a connection terminal 1, since the contact part 9 has the hollow part 11 and the contact parts 13 and 13 of a simple structure, enlargement can be suppressed and contact resistance can be reduced with a simple structure. it can.

  In addition, in the connection terminal which concerns on embodiment of this invention, a contact part is formed in a semi-cylinder shape, for example, you may form a contact part in a half-square column shape.

  In addition, the hollow portion is formed in a semicircular shape in a side view, but is not limited to this, and both sides of the hollow portion such as a concave shape like a semi-rectangular shape in a side view are used as contact portions, and an apparent contact surface The shape of the hollow part may be such as long as the diameter can be increased and the tendency of current flow can be utilized.

DESCRIPTION OF SYMBOLS 1 ... Connection terminal 3 ... Mating terminal 5 ... Connection part 7 ... Elastic piece 9 ... Contact part 11 ... Hollow part 13 ... Contact part

Claims (1)

An elastic piece having an urging force toward the connection portion of the mating terminal, and a surface protruding from the elastic piece toward the connection portion side of the mating terminal and contacting the surface of the connection portion of the mating terminal by the urging force of the elastic piece A connection terminal provided with a contact portion,
The contact portion is formed in a semi-cylindrical shape along the width direction of the elastic piece, and a groove shape projecting in a direction in which a central portion in the length direction of the elastic piece is away from the connection portion of the mating terminal. And a belt-like contact portion formed on each side of the hollow portion in the length direction of the elastic piece.

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