Electric connector assembly

Abstract: A connector assembly including a first connector having female terminals which are short-circuited through a short-circuiting terminal while the first connector is not connected to a second one. When the second connector is plugged into the first connector, an insulating piece of the second connector breaks the short-circuit connection between the female terminals. The short-circuiting terminal has contact portions. At least one of the short-circuiting terminal contact portions has a side extension. The second connector has a rib adapted to press down the contact portions to form a gap between the short-circuiting terminals and the female terminals. The insulating piece is inserted between the gap thus formed, so that it encounters practically no resistance. This makes it possible to reduce the thickness of the insulating piece and thus to improve the long-term reliability of the connector assembly.

Description: This invention relates to a plug-in electric connector assembly including a first connector having terminals connected to a load and a means for keeping the terminals short-circuited while the first connector is not connected to the second one to prevent electrostatic failure of IC's and erroneous explosion of a detonating circuit for an air bag and to break the short-circuit connection when the first and second connectors are connected together, according to the preamble of claim 1. A conventional connector assembly is disclosed in Unexamined Japanese Patent Publication 60-232674 and a connector assembly according to the preamble of claim 1 is disclosed in Examined Japanese Utility Model Publication 3-29896. These connectors have a first connector having connector terminals connected to a load through signal wires and a short-circuiting terminal pressed against the connector terminals for short-circuiting the connector terminals while the first connector is not connected to the second one. Since the connector terminals are short-circuited, their potentials are kept equal. The second connector has an insulating piece adapted to be inserted between the connector terminals and the short-circuiting terminal of the first connector when the second connector is plugged into the first one to separate the short-circuiting terminal from the connector terminals, thereby breaking the short-circuit between the connector terminals. When the insulating piece is inserted, the short -circuiting terminal is resiliently deformed. Thus, in order to minimize the stress relaxation of the short-circuiting terminal (buckling at its spring portion), the insulating piece has to be as thin as possible. But since the insulating piece is directly pressed against the short-circuiting terminal to deform and separate it from the connector terminals, it will easily break or chip if it is not sufficiently thick. The insulating piece disclosed in either of the above-mentioned publications is provided with a guide taper to reduce the resistance when it is inserted. But still, it is impossible to sufficiently reduce the possibility of breakage or chipping of the insulating piece. In an arrangement according to a further prior art (US-A-4,978,311), protrusions are arranged vertically. The connector of the arrangement is thus inevitably very thick. The protrusion as the rib pushes up an intermediate portion of the short-circuiting terminal, so that the spring force of the short-circuiting terminal inevitably acts on the other protrusion as the insulating piece. This makes it difficult to use a sufficiently thin insulating piece or protrusion. The document US-A-5,263-872 describes a contact element having a mid-portion with an inclined portion at the face thereof. In order to ensure good function, the leg must have a specifically curved shape. In this prior art, especially from the Figures, it is apparent that the male terminals are inserted into the female terminals well before the short-circuiting terminal is pushed down by the rib. This means that the short-circuiting terminal remains in contact with the female terminals for a long time after the male terminals have been inserted into the female terminals. This increases the possibility of a large current flowing between the female terminals through the short-circuiting terminal. The document US-A-4,850,888 relates to a connector element comprising an insulating part which has an entirely different configuration than the insulating piece and the rib of the embodiment of the present invention. The object of this invention is to improve the long-term reliability of a connector assembly by providing a means which makes it possible to reduce the thickness of the insulating piece without increasing the possibility of breakage and chipping. According to this invention, there is provided a connector assembly according to claim 1. The short-circuiting terminal is separated from the terminals of the first connector by a sufficiently thick and strong rib. The insulating piece itself encounters no significant resistance when inserted. It is thus possible to use a sufficiently thin insulating piece. Other features and objects of the present invention will become apparent from the following description made with reference to the accompanying drawings. Fig. 1A is a vertical sectional view of the connector assembly embodying this invention; Fig. 1B is a perspective view of the same showing its inner structure; Fig. 2A-2C show how the rib is inserted; Fig. 3 is a perspective view of a rib provided between the pair of connector terminals; Fig. 4A is a side view of a rib having a step protruding from the insulating piece; and Figs. 4B and 4C show how the rib is inserted. Fig. 1 shows the connector assembly embodying this invention. As shown in Fig. 1A, it comprises a first connector 1 and a second connector 5 into which the first connector can be plugged. The first connector 1 has a housing 2 in which are mounted a pair of female terminals 3 connected to signal wires 10 connected to a load, and a short-circuit terminal 4 for short-circuiting the female terminals 3. The second connector 5 has a housing 6 in which are mounted a pair of male terminals 7 corresponding to the female terminals 3 of the first connector 1 and connected to signal wires 11 connected to a power source. An insulating piece 8 and a rib 9 are received in a hood 6a of the housing 6 in which the housing 2 of the first connector 1 is inserted. This connector assembly may be optionally provided with a simple locking mechanism 12 for keeping the connectors locked in position. It comprises e.g. a resilient arm 12a having a barb 12b adapted to engage in a recess 12c. As shown in Fig. 1B, the short-circuiting terminal 4 has two contact portions 4a formed by bending. When the two connectors are not connected together, the contact portions 4a are pressed in the housing 2 against the female terminals 3 in a resiliently deformed state, so that the female terminals 3 are short-circuited through the short-circuiting terminal 4. One of the contact portions 4a has an extension 4b protruding sideways from one of the female terminals 3. The rib 9 is provided at a position opposite to the extension 4b and has a tapered guide surface at its front end. The front end of the insulating piece 8 is located near the rear end of the tapered guide surface. The insulating piece 8 is adapted to be inserted between the female terminals 3 and the contact portions 4a of the short-circuiting terminal 4. When the first connector 1 is pushed into the second connector 5, the rib 9 is inserted into the space on the outer side of one of the female terminals 3. Preferably, the male terminals 7 are positioned so that their tips are slightly inserted in the female terminals 3 when the tapered guide surface of the rib 9 abuts the contact portion 4a as shown in Fig. 2B. By further pushing in the second connector 5 into the first connector 1 from the state of Fig. 2B, the rib 9 advances while gradually deforming the contact portion 4a to create a gap between the contact portion 4a and the female terminal 3, so that the insulating piece 8, which follows the rib 9, can be smoothly inserted into the gap thus formed without encountering any major resistance. Thus, no high strength is needed for the insulating piece 8, so that it is possible to reduce the fatigue of the contact portion 4a by using a thin insulating piece 8. The insulating piece 8 as shown in Fig. 1, which can insulate only one of the female terminals 3 from the short-circuiting terminal 4, would be sufficient. But instead, an insulating piece which can insulate both female terminals from the short-circuiting terminal may be used. Preferably, the insulating piece 8 and the rib 9 are formed as an integral member as shown, because the rib 9 integral with the insulating piece 8 serves to reinforce the insulating piece 8, making it possible to further reduce its thickness. In order to reduce the width of the entire connector assembly, the extension 4b may be provided not on the outer side of one of the contact portions 4a as shown in Fig. 1 but on its inner side, i.e. between the female terminals 3. In this case, as shown in Fig. 3, two insulating pieces 8 reinforced with a single rib 9 may be used. Also, ribs 9 and extensions 4b may be provided on both sides of the female terminals 3 to improve the balance of pressure by the contact portions 4a and to more stably reinforce the insulating pieces 8 with the ribs. It is also preferable to provide a step h as shown in Fig. 4. By providing the step, the contact portions 4a are deformed by a distance equal to the sum of the thickness of the insulating piece 8 and the height of the step h, whereas in the arrangement of Fig. 1, having no such step, the contact portions 4a are deformed only by a distance equal to the thickness of the insulating piece 8. Thus, in the arrangement of Fig. 4, it is possible to prevent the insulating piece 8 from coming into contact with the contact portions 4a when the insulating piece is inserted. The contact portion 4a is deformed to the maximum by step h only while the insulating piece 8 is being inserted. Once the insulating piece 8 is fully inserted, the contact portion 4a clears the step h and is pressed against the thin insulating piece 8 as shown in Fig. 4C. According to this invention, the rib provided on the second connector presses and deforms the short-circuiting terminal, forming a gap between the connector terminals and the short-circuiting terminal. The insulating piece is then inserted into the gap thus formed, encountering practically no resistance. It is thus possible to use a sufficiently thin insulating piece. Such a thin insulating piece can retard stress relaxation at the spring portion of the short-circuiting terminal, thus improving the long-term reliability of the connector assembly.

Claims: Connector assembly comprising a first connector (1) having a housing (2), a pair of first connector terminals (3) provided in said housing (2), and a short-circuiting terminal (4) mounted in said first connector (1) and pressed against said pair of first connector terminals (3) for short-circuiting said pair of first connector terminals (3), and a second connector (5) adapted to be inserted into said first connector (1) and having a pair of second connector terminals (7) and an insulating piece (8) adapted to be inserted between at least one of said pair of first connector terminals (3) and said short-circuiting terminal (4) to break the short circuiting between said pair of first connector terminals (3) when said first and second connectors (1; 5) are connected together, characterized in that the short-circuiting terminal (4) has an extension (4b) protruding to one side of at least one of said first connector terminals (3), that the second connector (5) is provided with a rib (9) adapted to press up said extension (4b) of said short-circuiting terminal (4) to separate it from said first connector terminals (3) when said second connector (5) is inserted into said first connector (1) and before said insulating piece (8) is inserted into between said short-circuiting terminal (4) and at least one of said pair of first connector terminals (3) provided in the housing (2) of said first connector (1), said insulating piece (8) having its top surface not above the top surface of said rib (9), that said rib (9) has its tip protruding ahead of the tip of said insulating piece (8) and the tip of said second connector terminals (7) in the direction of insertion into said first connector terminals (3), and that said first and second connector terminals (3 ; 7), said short-circuiting terminal (4) and said rib (9) are arranged such that said short-circuiting terminal (4) is pushed up by said rib (9) substantially simultaneously when said first and second connector terminals (3 ; 7) are connected together. Connector assembly as claimed in claim 1, characterized in that said insulating piece (8) is integral with said rib (9). Connector assembly as claimed in claim 1, characterized in that the top surface of said insulating piece (8) is below the top surface of said rib (9). Connector assembly as claimed in claim 1, characterized in that the rib (9) has a tapered guide portion at the tip thereof and said insulating piece (8) has its tip disposed near the rear end of said tapered guide portion. Connector assembly as claimed in claim 1, characterized in that the short-circuit terminal (4) has two contact portions (4a). Connector assembly as claimed in claim 1, characterized in that the rib (9) and the insulating piece (8) are arranged side by side in the width direction of the short-circuiting terminal (4).

Inventors: ITOU MITSURU, OKUMURA HITOSHI, SUZUKI MASAJI, TAKANO SATOSHI, TAKATA KENSAKU, ITOU, MITSURU, OKUMURA, HITOSHI, SUZUKI, MASAJI, TAKANO, SATOSHI, TAKATA, KENSAKU, TAKANO, SATOSHI, C/O OSAKA WORKS, TAKATA, KENSAKU, C/O OSAKA WORKS
Applicants: SUMITOMO ELECTRIC INDUSTRIES, SUMITOMO WIRING SYSTEMS, SUMITOMO ELECTRIC INDUSTRIES, LTD., SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1996
Main classification: H01R13
IPC codes: H01R13