JP3433670B2 - Female terminal fitting - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a female terminal fitting.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open No. 10-409 discloses a female terminal fitting.
No. 88 is disclosed. The female terminal fitting has a box-shaped fitting portion having an open front surface, and an elastically flexible elastic contact piece folded back from the lower edge of the front end of the fitting portion. An embossed portion that is raised in an arc shape when viewed from the front is formed. A tab of the male terminal fitting is fitted into the fitting portion of the female terminal fitting, and the tab makes line contact with the embossed portion at a predetermined contact pressure while elastically bending the elastic contact piece, and thus the male and female terminal fittings are provided. Can be conducted.

[0003]

In recent years, there has been a demand for miniaturization of the terminal fittings. However, when the tabs of the male terminal fittings are formed by folding both side edges inward, the tabs should be miniaturized. As shown in FIG. 5, the lower surface 1a of the tab 1 opposite to the folded back has a generally curved shape, and the lowermost end point 1p of the lower surface 1a of the tab 1 and the uppermost end point 2p of the embossed portion 2 are aligned. Line contact (point contact when viewed from the front) comes to occur in the state. However, the tab 1 and the embossed portion 2
Since the curved surfaces are in contact with each other, the tab 1 is easily displaced in the width direction with respect to the elastic contact piece 3. When the lateral displacement occurs, the tab 1 and the embossed portion 2 come into contact with each other on the inclined surfaces as shown in FIG. 6, but in this state, the elastic deflection amount of the elastic contact piece 3 is smaller than the regular deflection amount, The predetermined contact pressure cannot be secured. The present invention has been made in view of the above circumstances, and an object thereof is to ensure a predetermined contact pressure even when the tab and the elastic contact piece are laterally displaced.

[0004]

The invention according to claim 1 is the front
In a female terminal fitting provided with an elastic contact piece that comes into elastic contact with a tab of a male terminal fitting inserted from above, the elastic contact piece is bent in a chevron shape when viewed from the side.
Shape forms a, before the top portion of the resilient contact piece
The contact area with the tabs is
A contact protrusion that is in the form of an inclined flat slope is formed,
The tops of the contact protrusions are continuous at a constant height in the width direction.
Is a top edge that is in contact with the tab
It has a structure. The invention of claim 2 is characterized in that, in the invention of claim 1, the contact portion of the contact projection with the tab is formed in a mountain shape capable of point contact with the tab in a side view. .

The invention of claim 3 relates to claim 1 or claim 2.
The invention is characterized in that the contact projection is formed by partially knocking out the elastic contact piece.

[0006]

<Advantages and effects of the invention><Invention1> Since the elastic contact piece is formed with a contact projection having a constant height, the contact surface of the tab with the elastic contact piece is curved and the tab is formed. Even if is displaced relative to the elastic contact piece in the width direction, the amount of elastic deflection of the elastic contact piece is kept constant, and a regular contact pressure is secured between the tab and the elastic contact piece. It

<Invention of Claim 2> Since the elastic contact piece is adapted to make point contact with the tab at its top edge portion when viewed from the side, the contact form with the tab is point contact or line contact. Therefore, a higher contact pressure can be secured as compared with the case of surface contact. <Invention of Claim 3> Since the contacting protrusion is formed by partially striking out, the elastic contact piece is unlikely to be deformed. Therefore, it is possible to prevent the contact pressure from deviating due to the deformation of the elastic contact piece.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment> A first embodiment of the present invention will be described below with reference to FIGS. In the female terminal fitting 10 of the present embodiment, a barrel portion 11 for crimping an electric wire (not shown) is formed at a rear end portion thereof, and a square tubular fitting portion 12 is formed at a front end portion thereof. There is. The fitting portion 12 is open to the front, and the tab T of the male terminal fitting is inserted into the fitting portion 12 from the front (left side in FIG. 2) from this opening. The fitting portion 12 is composed of a bottom plate portion 13, side wall portions 14 raised from the left and right side edges of the bottom plate portion 13, and a top plate portion 15 in which upper end edges of both side wall portions 14 are horizontally bent and closely stacked. Become.

From the front edge of the bottom plate portion 13, an elastic contact piece 16 which is folded back into the fitting portion 12 is formed. The elastic contact piece 16 is bent in a mountain shape when viewed from the side, and its extending end (folding end) is elastically contacted with the upper surface of the bottom plate portion 13. The elastic contact piece 16 elastically bends so as to be crushed while expanding and deforming the top of the mountain. Further, at a position slightly forward of the top of the elastic contact piece 16, a part of the bottom plate portion 13 is cut and raised upward and bent to bend the excessive deflection restricting protrusion 17.
When the elastic contact piece 16 abuts against the excessive bending restriction protrusion 17 from above, the elastic contact piece 16 is restricted from excessive bending exceeding its elastic limit. In addition, the opening portion of the bottom plate portion 13 formed by the formation of the excessive bending restriction protrusion 17 has a retaining lance (not shown) provided in the housing when the female terminal fitting 10 is inserted into the housing (not shown). The retaining hole 18 is engaged.
Further, a flat pressing portion 19 that faces the elastic contact piece 16 is formed on the lower plate portion of the two-layered upper surface plate portion 15 by tapping a part thereof downward. The tab T is elastically clamped between them.

A contact projection 20 is formed on the elastic contact piece 16 by partially knocking it out from the top of the elastic contact piece 16 to the front thereof. The contact projection 20 has a trapezoidal shape when viewed from the front side, and the upper surface of the contact projection 20 has a flat slope shape that is inclined forward and downward. And
When the contact protrusion 20 is viewed from the side, the top of the mountain-shaped portion at the rear end (the portion corresponding to the top of the elastic contact piece 16) has a constant height in the width direction when viewed from the front. And is formed as a top edge portion 20A having a chevron cross section that linearly extends in the width direction (the left-right direction in FIGS. 1 and 4). The uppermost portion of the top edge portion 20A comes into point contact with the lower surface Ta of the tab T when viewed from the side. Top edge portion 2 in a state where the tab T is not fitted
The distance between 0A and the pressing portion 19 is set smaller than the thickness of the tab T by a predetermined dimension. By properly setting this interval, the elastic deflection amount of the elastic contact piece 16 when the tab T is fitted becomes an appropriate amount, and by extension, the elastic contact piece 16 (contact projection 20) and the tab T are separated. The contact pressure becomes appropriate.

The tab T is formed by bending an elongated plate member inwardly symmetrically at both side edges toward the upper surface side. When the width dimension is made sufficiently large with respect to the plate thickness, a flat region is secured on the lower surface of the tab T after molding, but the tab T of the present embodiment is downsized. Therefore, the width dimension is set to be relatively small with respect to the plate thickness, and as a result, as shown in FIG.
Has a curved shape. In addition, the above-mentioned top edge portion 20
The distance between A and the pressing portion 19 is set in consideration of this curved shape. That is, the height from the lowermost position of the curved lower surface Ta of the tab T to the uppermost position of the folding end Tb of the tab T is defined as the thickness dimension of the tab T, and an interval smaller than this dimension is the top edge portion 20A and the pressing portion. It is set as a space dimension with respect to 19.

Regarding the width dimension of the tab T and the inner width dimension of the fitting portion 12, when the tab T and the side wall portion 14 of the fitting portion 12 come into contact with each other, the fitting resistance increases. It is made smaller than the inner width of the joint portion 12 so that a gap in the width direction is formed between them. Also, in order to share the parts, without using a female terminal fitting of a size compatible with the tab T,
A female terminal fitting that is one size larger than the fitting size may be combined, and in such a case, the gap in the width direction between the tab T and the fitting portion 12 is further increased.

In such a case, due to an error in assembling the terminal fitting and the housing, the tab T extends in the width direction from the center position, which is a regular contact position with the fitting portion 12 (elastic contact piece 16). There is a risk of slipping. However, in the present embodiment, since the top edge portion 20A with which the tab T contacts has a constant height in the width direction, the distance between the top edge portion 20A and the holding portion 19 is constant in the width direction. Therefore, the elastic deflection amount of the elastic contact piece 16 when the tab T is laterally displaced is the same as that when the tab T is in contact with the top edge portion 20A at the regular center position. Thus, according to the present embodiment,
Since the contact area of the tab T in the elastic contact piece 16 is the top edge portion 20A having a constant height in the width direction, the tab T
Does not change even if the width fluctuates in the width direction, and thus the contact pressure between the elastic contact piece 16 and the tab T is kept constant. Further, since the elastic contact piece 16 is adapted to contact the tab T at the highest point 20A at one point when viewed from the side thereof, the contact form with the tab T is point contact or line contact, and Compared with the case of contact,
A high contact pressure can be secured. Further, in the present embodiment, the contact projection 20 is formed by partially knocking out the elastic contact piece 16, so that the elastic contact piece 16 is formed.
Is less likely to occur, which prevents the contact pressure from deviating due to the deformation of the elastic contact piece 16.

<Other Embodiments> The present invention is not limited to the embodiments described above and illustrated in the drawings, and various modifications can be made without departing from the scope of the invention.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view of a female terminal fitting according to a first embodiment.

FIG. 2 is a partial horizontal sectional view of the female terminal fitting of the first embodiment.

FIG. 3 is a front view of the female terminal fitting of the first embodiment.

FIG. 4 is a partially cutaway front view showing a state in which a tab is fitted to the female terminal fitting of the first embodiment.

FIG. 5 is a front view of a conventional example.

FIG. 6 is a front view showing a state in which a tab is laterally displaced in a conventional example.

[Explanation of symbols]

10 ... Female terminal fitting 16 ... Elastic contact piece 20 ... Contact protrusion 20A ... Top edge T ... tab

Claims (3)

(57) [Claims] 1.Inserted from the frontOn the tab of the male terminal fitting
An elastic contact piece is provided that contacts elastically while flexing.
In the female terminal fittingThe elastic contact piece is bent in a chevron shape when viewed from the side.
The The elastic contact pieceOf the area from the top to the front of the
Is a flat slope where the contact surface with the tab is inclined forward and downward.
A contact protrusion that is formed into a shape is formed, The tops of the contact protrusions are continuous at a constant height in the width direction.
Is a top edge that is in contact with the tab
ing Female terminal fittings characterized by the above. 2. The female terminal fitting according to claim 1, wherein a contact portion of the contact projection with the tab has a chevron shape capable of point contact with the tab in a side view. 3. The female terminal fitting according to claim 1, wherein the contact projection is formed by partially knocking out the elastic contact piece.