The invention relates to a connector mounted on a surface of a circuit board using surface mount technology (SMT) that has a housing with a metal fitting having a soldering section for securing the connector to the circuit board.
In recent years, connectors mounted using SMT have gained popularity for interconnecting circuit boards because they easily make electrical connections to elements on the circuit board, they have high packaging contact densities, and other advantages. The connector is electrically connected to the circuit board by soldering a lead end of each of the contacts provided inside a housing of the connector to a pad on a surface of the circuit board. When the circuit board mounted with the connector is used, for example, in an automobile, however, the circuit board is subjected to vibrations, which can cause the connector to become disconnected from the circuit board. In order to securely connect the connector to the circuit board, Japanese Patent Laid-Open Nos. 2000-294324 and H8-45579 teach attaching metal fittings having soldering sections to the connector. The soldering sections of the metal fittings are soldered to the pads on the surface of the circuit board to securely connect the connector to the circuit board.
Due to the demand for smaller connectors, it is necessary to minimize the total length of the connector including the soldering section which protrudes from a sidewall of the housing of the connector. However, if the soldering sections of the metal fittings are arranged as close as possible to the housing, in order to minimize the total length of the connector, it becomes difficult to visually inspect whether the soldering sections are soldered to the pad on the circuit board due to the presence of the housing. In addition, due to sudden changes in ambient temperature, for example, in an automobile, the circuit board and the housing of the connector are subject to thermal expansion and contraction. As the circuit board and the housing are respectively formed of different materials, there is a difference in the amount of thermal expansion and contraction between them. In a case where the connector is securely fixed to the circuit board by soldering the metal fittings thereof to the circuit board, the difference in thermal expansion and contraction causes stress on the soldering section of the metal fittings and may eventually disconnect the soldering section from the circuit board. If the soldering section of the connector is removed from the circuit board, it is more likely to be electrically disconnected from the circuit board.
It is therefore an object of the invention to provide a connector mounted on a surface of a circuit board using SMT that has a housing with a metal fitting having a soldering section for securing the connector to the circuit board wherein visual inspection of the solder is possible, the mounting area of the connector is minimized, and stress applied to the soldering section of the metal fitting is alleviated.
This and other objects are achieved by a surface mount technology connector comprising a housing provided with a plurality of contacts. At least one metal fitting is fixed to a sidewall of the housing. The metal fitting has a base and a soldering section for soldering to a circuit board. The base has a smaller width than the soldering section. The soldering section extends from a substantial center of the base with respect to the width thereof. The soldering section and a portion of the base extend approximately perpendicular to and away from a bottom of the sidewall of the housing. The sidewall of the housing has a solder viewing section at each side of the base. The solder viewing section retracts inward as the solder viewing section approaches the soldering section to expose the soldering section at the bottom of the sidewall of the housing.
This and other objects are further achieved by s surface mount technology connector, comprising a housing provided with a plurality of contacts. At least one metal fitting is fixed to a sidewall of the housing. The metal fitting has a base extending substantially parallel to the sidewall and a soldering section for soldering to a circuit board. The soldering section extends from a substantial center of the base with respect to a width thereof approximately perpendicular to and away from a bottom of the sidewall of the housing such that a gap is formed between the base and the bottom of the sidewall of the housing.
As shown in
As shown in
The metal fittings 30 are fixed to the housing 10, for example, by press-fitting each end of the fitting section 33 in a direction of width in a press-fit section 1201 provided at ends of the housing 10 with respect to a longitudinal direction of the sidewall 120, as shown in
The soldering section 31 is soldered to the surface of the circuit board, as shown in
As shown in
As shown in
In the connector 1 according to the invention, the solder viewing sections 1203, which are positioned at each side of the base 32, retract inward and thereby enable the solder to easily enter across the perimeter of the soldering section 31 including the inner edge 31b of the soldering section 31. As a result, the metal fitting 30 is securely soldered to the circuit board and visual inspection of the solder from above is possible, even if the inner edge 31b of the soldering section 31 is near the bottom 120L of the sidewall 120. Thus, the connector 1 is configured such that the metal fitting 30 can be securely soldered to the circuit board and visual inspection of the solder is capable of being performed while minimizing the mounting area of the connector 1. In addition, the mounting area of the connector 1 can be minimized because the inner edge 31b of the soldering section 31 is close to the bottom 120L of the sidewall 120 of the housing 10.
The housing 10 of the connector 1 of the present invention may be formed, for example, from a heat-resistant engineering plastic such as polyphenylene sulfide (PPS). The circuit board may be made, for example, from glass epoxy resin-system materials. Accordingly, there is a difference in the amount of thermal expansion and contraction between the housing 10 and the circuit board. When the thermal expansion of the housing 10 is larger than that of the circuit board, the gap S in
Because the height h of the base 32 is slightly longer than the width w of the base 32, the base 32 has some flexibility. Therefore, tension applied to the metal fitting 30 is absorbed by the flexibility of the base 32 even if thermal expansion of the circuit board is larger than that of the housing 10 and the expanded circuit board tries to pull the metal fitting 30. In addition, if the thermal contraction of the housing 10 is larger than that of the circuit board, and the contracted housing 10 tries to pull the metal fitting 30, tension applied to the metal fitting 30 is absorbed by the flexibility of the base 32. In both cases, stress applied to the soldering section 31 of the metal fitting 30 is alleviated, which can prevent removal of the metal fitting 30 from the circuit board, even if the housing 10 or the circuit board contracts after it has expanded. Consequently, the connector 1 can be securely mounted, for example, on a circuit board in an automobile where it is subjected to sudden changes in ambient temperature or, for example, on a circuit board loaded with a heat-producing component.
The foregoing illustrates some of the possibilities for practicing the invention. Many other embodiments are possible within the scope and spirit of the invention. It is, therefore, intended that the foregoing description be regarded as illustrative rather than limiting, and that the scope of the invention is given by the appended claims together with their full range of equivalents.
Number | Date | Country | Kind |
---|---|---|---|
2004-316347 | Oct 2004 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
5449297 | Bellomo et al. | Sep 1995 | A |
5533908 | Henry et al. | Jul 1996 | A |
5639248 | Yagi | Jun 1997 | A |
5735696 | Niitsu et al. | Apr 1998 | A |
5876217 | Ito et al. | Mar 1999 | A |
5931689 | Patel | Aug 1999 | A |
5971809 | Ho | Oct 1999 | A |
6129589 | Simmel et al. | Oct 2000 | A |
6254429 | Morita | Jul 2001 | B1 |
6338630 | Dong | Jan 2002 | B1 |
6338633 | Dong | Jan 2002 | B1 |
6923659 | Zhang et al. | Aug 2005 | B2 |
20030100211 | Wu | May 2003 | A1 |
Number | Date | Country |
---|---|---|
08-045579 | Feb 1996 | JP |
2000-294324 | Oct 2000 | JP |
Number | Date | Country | |
---|---|---|---|
20060094298 A1 | May 2006 | US |