Bulb socket terminal

Abstract

A bulb socket terminal to be accommodated in a socket body of a connector bulb socket. The terminal includes a base, an elastic contact portion adapted to contact a filament or an earth of a bulb on one side of the base, and a connecting portion adapted to be connected to a connector on the other side thereof. The bulb socket terminal is integrally formed intermediate of the elastic contact portion and the connecting portion with a resin flow blocking wail which contacts an insert-molding metal mold to seal an area of the elastic contact portion at the time of insert-molding. Accordingly, the area where the elastic contact portion extends is sealed by the rein flow blocking wall at the time of insert-molding with use of the metal mold to thereby prevent the resin from flowing into this area. Therefore, the spring elasticity of the elastic contact portion will not be restricted.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a bulb socket terminal in an automotive lamp, and more particularly to a terminal having a structure which may be insert-molded in a socket body.

2. Description of the Relevant Art

Conventionally, a technique of insert-molding a terminal in a housing body of a connector is known, but a technique of insert-molding a bulb socket terminal in a bulb socket with a connector has not yet been established.

Japanese Utility Model Laid-open Publication No. 59-79990 discloses a connector bulb socket as shown in FIGS. 8 to 12. Referring to FIGS. 8 to 12, the bulb socket is constructed of a socket body A, a terminal C adapted to contact a filament end B.sub.1 of a bulb B, and a ground terminal D adapted to contact a ground end B.sub.2 of the bulb B. The socket body A, the terminal C and the ground terminal D are independently manufactured before both the terminals C and D are received through a bulb insert hole a and secured in said socket body A.

Referring to FIGS. 13A and 13B, if the terminal C to contact the filament end B.sub.1 is insert-molded in the socket body A, a metal mold E.sub.1 may be used for enclosing a contact portion b adapted to elastically contact the filament end B.sub.1. In this case, if resin is filled in a hatched area G (corresponding to the socket body A) alone to secure the terminal C, there will be no problem. However, the resin actually flows also into a hatched area H because there is no wall or the like for inhibiting intrusion of the resin. (Although another metal mold to be coupled with the metal mold E.sub.1 is actually provided on the opposite side of the metal mold E.sub.1 with respect to the hatched area G, such a metal mold is not shown for the simplicity of the drawing.) For the above-mentioned reason, an amount of elastic displacement of the contact portion b is restricted to cause insufficient electric contact with the filament B.sub.1. To prevent the intrusion of the resin into the hatched area H, it may be considered to form the contact portion b into an S-shaped contact portion c as shown in FIGS. 14A and 14B. However, there remains a problem such that the resin still flows into an area of the contact portion c as shown by the arrows through a necessary clearance between the terminal C and a metal mold E.sub.2 or a gap therebetween due to lack of uniformity in finished sizes of the terminal C.

In case of insert-molding the ground terminal D, it may be considered to enclose a contact portion d adapted to contact the ground end by means of a metal mold F as shown in FIGS. 15A and 15B. However, the resin will flow into not only the hatched area G but also a hatched area J for the same reason as the above. As a result, the contact portion d is secured by the resin molded in said hatched area J, thus causing a problem that the bulb cannot be inserted.

SUMMARY OF THE INVENTION

It is accordingly an object of the present invention to provide a bulb socket terminal having a structure which can be insert-molded in a socket body of a connector bulb socket.

According to the present invention, there is provided a bulb socket terminal to be accommodated in a socket body of a connector bulb socket, the terminal including a base plate, an elastic contact portion adapted to contact a filament or a ground of a bulb on one side of the base plate, and a connecting portion adapted to be connected to a connector on the other side thereof. The bulb socket terminal is integrally formed intermediate of the elastic contact portion and the connecting portion with a resin flow blocking wall which contacts an insert-molding metal mold to seal an area of the elastic contact portion at the time of insert-molding.

As mentioned above, the resin flow blocking wall is formed at an intermediate between the elastic contact portion adapted to contact the bulb and the connecting portion adapted to be connected to a connector, so that the area of the elastic contact portion may be sealed by the resin flow blocking wall upon insert-molding with use of a metal mold to thereby inhibit the resin flow into this area. Therefore, the spring elasticity of the elastic contact portion will not be restricted.

Other objects and features of the invention will be more fully understood from the following detailed description and appended claims when taken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevational view of the bulb socket terminal of the present invention as fixedly accommodated in the socket body by insert-molding;

FIG. 2 is a cross section taken along the line II--II in FIG. 1;

FIG. 3 is a cross section taken along the line III--III in FIG. 1;

FIG. 4A is an enlarged perspective view of the terminal 5 shown in FIG. 1;

FIG. 4B is an enlarged perspective view of a modified form of the terminal 5;

FIG. 5 is an enlarged perspective view of the earth terminal 6 shown in FIG. 1;

FIG. 6A is a sectional front view of the terminal 5 upon insert-molding with a metal mold shown in section;

FIG. 6B is a sectional side view of FIG. 6A;

FIG. 6C is a plan view of FIG. 6A;

FIG. 7A is a sectional front view of the earth terminal 6 upon insert-molding with a metal mold shown in section;

FIG. 7B is a sectional side view of FIG. 7A;

FIG. 8 is a vertical sectional view of the bulb socket in the prior art;

FIG. 9 is a cross section taken along the line IX--IX in FIG. 8;

FIG. 10 is a cross section taken along the line X--X in FIG. 9;

FIG. 11 is an enlarged perspective view of the terminal C shown in FIG. 8;

FIG. 12 is an enlarged perspective view of the ground terminal D shown in FIG. 8;

FIG. 13A is an elevational view of the terminal C of the prior art upon insert-molding with a metal mold shown in section;

FIG. 13B is a side view of FIG. 13A;

FIG. 14A is an elevational view of an improved form of the terminal C of the prior art upon insert-molding with a metal mold shown in section;

FIG. 14B is a side view of FIG. 14A;

FIG. 15A is an elevational view of the ground terminal D of the prior art upon insert-molding with a metal mold shown in section; and

FIG. 15B is a side view of FIG. 15A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

There will now be described a preferred embodiment of the present invention with reference to the drawings.

Referring to FIGS. 1 to 3, reference numeral 1 designates a socket body integrally formed of a synthetic resin. The socket body 1 has a bulb insertion hole 2 at one end thereof and a connector insertion hole 3 at the other end. The socket body 1 is formed with a central partition wall 4, in which a pair of terminals 5 to contact a filament end of a bulb (see FIG. 8) and a ground terminal 6 to contact a ground end of the bulb are fixedly received by insert-molding in the socket body 1.

Referring to FIG. 4A, the terminal 5 is integrally formed from a single thin sheet metal by press-bending. An L-shaped base portion 5a of the terminal 5 is bent in an S-shaped configuration at one end thereof to form an elastic contact portion 5b adapted to contact the filament end of the bulb. Further, the base portion 5a is bent vertically downwardly at the other end to form a tab portion 5c. The tab portion 5c is folded at its free end to form a connecting portion 5d adapted to be connected to a connector (not shown). Thus, the terminal 5 is insert-molded under the condition where the elastic contact portion 5b extends in the bulb insertion hole 2 while the connecting portion 5d extends in the connector insertion hole 3.

More specifically, the elastic contact portion 5b of the terminal 5 is formed through a first bent portion 5b.sub.1 continued to the base portion 5a, a slant portion 5b.sub.2 continued to the first bent portion 5b.sub.1, and a second bent portion 5b.sub.3 formed at a free end of the slant portion 5b.sub.2. Thus, the formation of the first bent portion 5b.sub.1 and the second bent portion 5b.sub.3 provides a double spring-elasticity. Further, the first bent portion 5b.sub.1 is formed at its opposite side edges with a pair of shoulders 5b.sub.4, so that the elastic contact portion 5b and the slant portion 5b.sub.2 are made narrower than the base portion 5a as shown by dotted lines P. Further, a free end Q of the elastic contact portion 5b is positioned sufficiently inside of a bent edge Q' of the first bent portion 5b.sub.1, preferably inside the shoulders 5b.sub.4. As will be hereinafter described, opposite side edge portions R formed laterally outside the dotted lines P serve as a resin flow blocking wall at the time of insert-molding.

FIG. 4B shows an improvement of the terminal 5 shown in FIG. 4A. In the terminal 5 there is a possibility that a molding pressure of resin will be applied to the base portion 5a at the time of insert-molding by a metal mold, causing bending of the base portion 5a toward the elastic contact portion 5b as will be hereinafter described. Referring to FIG. 4B, the base portion 5a of an improved terminal 5' is integrally formed with a reinforcing plate 5e as formed by folding the base portion 5a from the side remote from the elastic contact portion 5b. The reinforcing plate 5e projects slightly from the bent edge Q' of the first bent portion 5b.sub.1 which also serves as the resin flow blocking wall as well as opposite side edge portion R' formed laterally outside a pair of dotted lines P' . In this case, the opposite side edge portions R' may be omitted.

Referring to FIG. 5, a base portion 6a of the ground terminal 6 is partially cut to be inwardly bent so as to form an elastic contact portion 6b adapted to contact the ground of the bulb. Further, the base portion 6a is formed at its lower end with an L-shaped bent portion 6c consisting of a horizontal portion 6c.sub.1 and a vertical portion 6c.sub.2. A horizontal tab 6d extends from the vertical portion 6c.sub.2 in perpendicular relationship to the base portion 6a, and a connecting portion 6e to be connected to a connector (not shown) is foldedly formed at a free end of the horizontal tab 6d. Thus, the ground terminal 6 is insert-molded under the condition where the elastic contact portion 6b extends in the bulb insertion hole 2 while the connecting portion 6e extends in the connector insertion hole 3.

As will be hereinafter described, the horizontal portion 6c.sub.1 and the vertical portion 6c.sub.2 of the L-shaped bent portion 6c serve as the resin flow blocking wall.

In the case that the connector insertion hole 3 in FIGS. 2 and 3 is bent in an L-shaped configuration with respect to the bulb insertion hole 2, the connecting portions 5d of the terminals 5 or 5' and the connecting portion 6e of the terminal 6 may be similarly bent in an L-shaped configuration at the respective end portions.

The operation of the preferred embodiment will now be described. As shown in FIGS. 5A to 5C, the elastic contact portion 5b of the terminal 5 is enclosed by a metal mold E' and the opposite side edge portions R formed from the base portion 5a to the first bent portion 5b.sub.1. Accordingly, resin is filled in a hatched area G which corresponds to an area where the partition wall 4 shown in FIGS. 2 and 3 is to be formed. That is, the resin is prevented from flowing into a space where the elastic contact portion 5b is allowed to be elastically displaced, by the opposite side edge portions R. Therefore, the spring elasticity of the elastic contact portion 5b will not be restricted by the resin molded, thus ensuring good contact with the filament of the bulb.

Similarly, the elastic contact portion 5b of the terminal 5' is enclosed by a metal mold (not shown) and the opposite side edge portions R' formed at the opposite side edges of the base portion 5a as well as the reinforcing portion 5e. In this case, a resin sealing effect can be doubled by the opposite side edge portions R' defined by dotted line P' and the reinforcing portion 5e. Furthermore, it is more advantageous that the base portion 5a is reinforced by the reinforcing portion 5e.

In a like manner, as shown in FIGS. 7A and 7B, a displacement space S of the elastic contact portion 6b of the ground terminal 6 is enclosed by a metal mold F' and the L-shaped bent portion 6c formed between the base portion 6a (inclusive of the elastic contact portion 6b) and the connecting portion 6e at an outside peripheral portion R' of the base portion 6a and the bent portion 6c. Accordingly, the resin is filled in a hatched area G only.

While the invention has been described with reference to specific embodiments, the description is illustrative and is not to be construed as limiting the scope of the invention. Various modifications and changes may occur to those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A bulb socket terminal insertable into a metal mold prior to insert-molding of a socket body of a connector bulb socket for accommodating a bulb having a filament and a ground end, said terminal comprising:

a base;

an elastic contact portion connected to said base and for contacting with at least one of said filament end and said ground end of said bulb on one side of said base;

a connecting portion connectable to a connector on another side of said base;

a resin flow blocking wall integral to said base for sealing and blocking entry of resin into an area behind said elastic contact portion during insert-molding of said socket body of said connector bulb socket, said resin flow blocking wall being formed between said elastic contact portion and said connecting portion and adapted to contact an insert-molding metal mold for said socket body during insert-molding of said socket body of said connector bulb socket, wherein said resin flow blocking wall includes a substantially L-shaped bent portion (6c) which comprises a substantially horizontal portion (6c.sub.1) and a substantially vertical portion (6c.sub.2), said substantially horizontal portion being connected to a lower end portion of said base; and

a substantially horizontal tab portion (6d) which is, at one end thereof, connected to and perpendicularly extended from said substantially vertical portion, and is, at an opposing end thereof, connected to said connecting portion,

wherein a horizontally projected dimension of said elastic contact portion is smaller than a horizontally projected dimension of said substantially horizontal portion 6c.sub.1.

2. The bulb socket terminal as in claim 1, wherein a maximum width of said elastic contact portion is smaller than the width of said substantially horizontal portion 6c.sub.1, and

wherein a horizontally projected length of said elastic contact portion is smaller than a horizontally projected length of said substantially horizontal portion 6c.sub.1.