Connector for circuit board

Abstract: To prevent the deformation of base end portions of L-shaped lead terminals. A restricting projection (displacement restricting means) 13 projects on the rear surface of the connector housing 10 so as to surround substantially the half of a base end portion 24U of each lead terminal 20U near a connector housing 10. Accordingly, even if an external bending force acts on the base end portions 24U, the deformation of the base end portion 24U is prevented by the restricting projection 13.

Description: The present invention relates to an electrical connector for mounting on a circuit board. A connector for a circuit board is, as shown in FIG. 5, constructed such that a plurality of lead terminals 2A, 2B are pressed into a connector housing 1. Projecting portions of the lead terminals 2A, 2B are bent in L-shape behind the rear surface of the connector housing 1, and the leading ends thereof serve as board mount portions 5A, 5B to be fitted into through holes 4 formed in a circuit board 4. In the above connector, the lead terminals 2A, 2B are arranged on upper and lower levels. In the lead terminals 2B on the lower level, base end portions 6B of the projected portions extending from the rear surface of the connector housing 1 to the bent portions are short. On the other hand, base end portions 6A of the lead terminals 2A on the upper level are made longer in order to avoid the interference with the lead terminals 2B on the lower level. Accordingly, there is a likelihood that the base end portions 6A of the lead terminals 2A on the upper level are deformed due to the interference from the outside. US-A-4 767 350 discloses an electrical connector according to the preamble of claim 1, for interconnecting a plurality of signals comprising a plurality of contacts. The contacts are bent downwardly around a ledge extending from the back wall of the connector and are then inserted into the terminal slots of a printed circuit board. US-A-5 032 085 discloses an electrical connector with three rows of contacts undergoing right angle bends from two columns suitable for joining to a printed circuit board. In this connector the contacts are bent around bend anvils provided on the lower surface of the connector housing. It is the object of the invention to provide a connector which prevents the deformation of base end portions of preferably L-shaped lead terminals and enables an easy bending of the terminals. This object is fulfilled by a connector having the features disclosed in claim 1 and a connector having the features disclosed in claim 6. Preferred embodiments are defined in the dependent subclaims. According to the invention, there is provided an electrical connector for mounting on a circuit board, according to claim 1. Furthermore, the displacement restricting means extends along a distance corresponding at least to about half of the length of the base end portions of the lead terminals. According to a preferred embodiment, there is provided a connector for a circuit board, in which lead terminals are so mounted in a connector housing as to project and the projecting portions of the lead terminals are bent to be connected with a circuit board, comprising: displacement restricting means for engaging base end portions of the lead terminals extending from the bent portions thereof to the connector housing to restrict the displacement of the base end portions. By providing the displacement restricting means, the deformation of the base end portions of the lead terminals can be prevented. Preferably, the displacement restricting means is so provided as to substantially project from or be rigidly fixed on the outer surface of the connector housing or is in a fixed disposition or relationship with respect to a surface of the connector housing at a position adjacent or neighbouring to the base end portions of the lead terminals. Further preferably, the displacement restricting means project from the connector housing in a direction away from engaging projections of the lead terminals for the engagement with a mating connector. Most preferably, the displacement restricting means substantially surround the base end portions of the lead terminals. According to a further preferred embodiment, the displacement restricting means is so provided as to project from the outer surface of the connector housing and surround the base end portions of the lead terminals. The base end portions of the lead terminals are protected from an external bending force by being surrounded by the displacement restricting means. Thus, the deformation of the base end portions can be prevented. Preferably, the connector housing comprises an alignment plate for aligning the leading ends of the lead terminals, preferably by passing or inserting them in positioning holes formed therein. Further preferably, the alignment plate is integrally mounted or mountable on the housing by means of holding means, preferably comprising one or more arms. According to the invention, there is furthermore provided an electrical connector for mounting on a circuit board comprising: a housing, a plurality of lead terminals comprising projecting portions which at least partially project from the rear end of the housing, whereby the projecting portions comprise bent portions at a distance from the housing in which the terminals are and bent at an angle different from 0° or 180°, preferably substantially at right angles, in the direction of and to be connected with the circuit board and base end portions extending substantially from the bent portions to the connector housing, an alignment plate for aligning the leading ends of the lead terminals, preferably by passing or inserting them in positioning holes formed therein, characterized by displacement restricting means being so provided as to project from the alignment plate and the projecting end thereof engaging the base end portions of the lead terminals at a distance from the bent portions. Preferably, the alignment plate is integrally mounted or mountable on the housing by means of holding means, preferably comprising one or more arms. The deformation of the base end portions of the lead terminals can be prevented by the engagement with the displacement restricting means projecting from the alignment plate. Preferably, the base end portions of the lead terminals are fitted into corresponding recesses formed in the displacement restricting means. Most preferably, the lead terminals are fitted into corresponding recesses such that frictional forces between inner walls of the recesses are high enough to substantially prevent the base end portions of the lead terminals from displacement in the corresponding recesses. These and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawings in which: FIG. 1 is a section of a first embodiment, FIG. 2 is a rear view of the first embodiment, FIG. 3 is a section of a second embodiment, FIG. 4 is a partial enlarged perspective view of the second embodiment, and FIG. 5 is a section of a prior art connector. <First Embodiment> Hereafter, a first embodiment of the invention is described with reference to FIGS. 1 and 2. A connector for a circuit board according to the invention is comprised of a connector housing 10 and a plurality of lead terminals 20U, 20L. The connector housing 10 has a receptacle 11 in the form of a rectangular tube projecting forward for the engagement with an unillustrated mating connector housing and a plurality of press holes 12U, 12L extending from the back end surface of the receptacle 11 to the rear surface of the connector housing 10. The press holes 12U, 12L are arranged on upper and lower levels, and e.g. five press holes 12U or 12L are arranged preferably substantially side by side preferably on each level. Narrow lead terminals 20U, 20L are pressed or inserted or mounted into the press holes 12U, 12L, respectively. The lead terminals 20U to be mounted in the press holes 12U on the upper level are substantially longer than the lead terminals 20L to be mounted in the press holes 12L on the lower level. The front ends of the respective mounted lead terminals 20U, 20L substantially horizontally projecting into the receptacle 11 substantially in parallel with each other and by the substantially same length serve as engaging portions 21 to be brought into contact with unillustrated mating terminal fittings. On the other hand, the portions of the lead terminals 20U, 20L projecting from the rear surface of the connector housing 10 at angles different from 0° or 180°, preferably at substantially right angles are bent preferably in L-shape. Leading ends of the lead terminals 20U, 20L extending downward from bent portions 22 serve as mount portions 23 which are to be fitted or inserted into through holes H formed in a circuit board P and secured by unillustrated solder, clamps or the like fixing device. The portions of the lead terminals 20U, 20L between the bent portions 22 and the rear surface of the connector housing 10 serve as base end portions 24U, 24L. The length of the base end portions 24U of the lead terminals 20U on the upper level are preferably substantially longer than that of the base end portions 24L of the lead terminals 20L on the lower level in order to avoid the interference with the lower lead terminals 20L. The connector housing 10 of this embodiment is provided with a means for preventing the deformation of the base end portions 24U of the lead terminals 20U. Specifically, a restricting projection (displacement restricting means) 13 is formed on a surface of the connector housing 10 from which the lead terminals 20U, 20L project, preferably on the substantially rear surface of the connector housing 10 by projecting a portion of the connector housing 10, preferably the opening edge of the upper press holes 12U in a direction A of extension of at least a portion of the lead terminals 20U, 20L, preferably substantially backward. A plurality of communication holes 14 (five in this embodiment) substantially coaxial with the respective press holes 12U are formed in the restricting projection 13. Accordingly, a portion, preferably substantially the half of the base end portion 24U of each upper lead terminal 20U near the connector housing 10 is accommodated in the corresponding communication hole 14. In other words, the restricting projection 13 reinforces and protects the base end portions 24U against an external force acting in such a direction to bend the base end portions 24U by substantially surrounding the base end portions 24U and/or by supporting the base end portion 24U in a direction against a bending force. Next, the action of this embodiment is described. The portions of the base end portions 24U of the upper lead terminals 20U surrounded by the restricting projection 13 have their strength against bending enhanced by the rigidity of the restricting projection 13. Further, the exposed portions of the base end portions 24U have an enhanced strength against bending because they are shortened by a portion, preferably substantially to half as compared to the case where the restricting projection 13 is not provided. Accordingly, the deformation of the base end portions 24U can securely be prevented even if an external bending force in an upward, downward, leftward and/or rightward direction acts on the outer surface of the restricting projection 13 or directly on the base end portions 24U. The lead terminals 20U are bent after being inserted through the connector housing 10. At this time, jigs (not shown) are placed on the inner and outer sides of the leading terminals 20U with respect to the bent portions. Since the projecting length of the restricting projection 13 is preferably substantially half the length of the base end portions 24U in this embodiment, there is no likelihood that the restricting projection 13 interferes the bending by interfering the jigs. <Second Embodiment> Next, a second embodiment of the invention is described with reference to FIGS. 3 and 4. This embodiment differs from the first embodiment in the construction of the displacement restricting means. Since the other construction is same or similar as the first embodiment, no description is given on the structure, action and effects of the same construction by identifying it by the same or similar reference numerals. In the second embodiment, the connector housing 10 is provided with an alignment or support plate 30 for aligning or supporting the mount portions 23 of the lead terminals 20U, 20L. The alignment plate 30 preferably has a substantially platelike shape as a whole. The opposite lateral ends of the alignment plate 30 are engaged or engageable with arms 16 projecting at a bottom portion of the rear surface of the connector housing 10 preferably from below and held engaged by an unillustrated locking means. This alignment plate 30 is formed with positioning holes 31 corresponding to the mount portions 23 of the respective lead terminals 20U, 20L. The mount portions 23 are so aligned as to substantially conform to the through holes H of the circuit board P by being inserted or insertable through the positioning holes 31. On the upper surface of the alignment plate 30, a preferably wall-shaped restricting rib 32 (displacement restricting means) stands. In the upper edge of the restricting rib 32 are formed recesses 33 which are engaged or engageable with the respective base end portions 24U on the upper level. With the base end portions 24U at least partially fitted or inserted or positioned in the recesses 33, the loose movement thereof in a downward, leftward and/or rightward direction can securely be restricted. The loose movement of the base end portions 24U in an upward direction can also be restricted or an extent thereof reduced by the frictional resistance with the inner walls 33A of the recesses 33. Accordingly, even if an external bending force acts on the base end portions 24U, the deformation of the base end portions 24U can securely be prevented. The alignment plate 30 is mounted on the connector housing 10 by being brought closer to the connector housing 10 to thereby fit the mount portions 23 into the respective positioning holes 31 and fit the base end portions 24U in the respective recesses 33. < Other Embodiments > The present invention is not limited to the described and illustrated embodiments. For example, the following embodiments are embraced by the technical scope of the present invention as defined in the claims. (1) Although the lead terminals 20U, 20L are arranged on the upper and lower levels in the connector housing 10 in the foregoing embodiments, the present invention is also applicable to connectors for a circuit board in which lead terminals are arranged on one level or on three or more levels. (2) Although the displacement of the base end portions 24U of the lead terminals 20U arranged substantially side by side is restricted by the single restricting projection 13 in the foregoing embodiments, the restricting projections may independently be formed and/or formed in groups for the respective lead terminals according to the invention. (3) Although the restricting projection 13 entirely surrounds the base end portions 24U of the lead terminals 20U in the foregoing embodiments, it may be engaged only with the upper and lower surfaces, opposite lateral surface, or any one of the surfaces of each base end portion according to the invention. LIST OF REFERENCE NUMERALS 10 Connector Housing 13 Restricting Projection (Displacement Restricting Means) 20U Lead Terminal 24U Base End Portion 30 Alignment Plate 32 Restricting Rib (Displacement Restricting Means) P Circuit Board

Claims: An electrical connector for mounting on a circuit board (P), comprising: a housing (10), a plurality of lead terminals (20U) comprising projecting portions which at least partially project from the rear end of the housing (10), whereby the projecting portions comprise bent portions (22) at a distance from the housing (10) in which the lead terminals (20U) are and bent at an angle different from 0° or 180°, preferably substantially at right angles, in the direction of and to be connected with the circuit board (P) and base end portions (24U) extending substantially from the bent portions (22) to the connector housing (10), characterized by displacement restricting means (13) extending from the rear end of the housing (10) for engaging at least partially the base end portions (24U) of the lead terminals (20U) to restrict in one or more directions the displacement of at least the base end portions (24), wherein the displacement restricting means (13) extends along a distance substantially equal to the half of the length of the base end portions (24U) of the respective lead terminal (20). A connector according to claim 1, wherein the displacement restricting means (13) is in a fixed disposition or relationship with respect to a surface of the connector housing (10) at a position adjacent to the base end portions (24U) of the lead terminals (20U). A connector according to claim 2, wherein the displacement restricting means (13) project from the connector housing (10) in a direction away from engaging projections (21) of the lead terminals (20U) for the engagement with a mating connector. A connector according to one or more of the preceding claims, wherein the displacement restricting means (13) substantially surround the base end portions (24) of the lead terminals (20U). A connector according to one or more of the preceding claims, wherein the connector housing (10) comprises an alignment plate (30) for aligning the leading ends (23) of the lead terminals (20U), preferably by passing or inserting them in positioning holes (31) formed therein. A connector according to claims 5, wherein the alignment plate (30) is integrally mounted or mountable on the housing (10) by means of holding means (16), preferably comprising one or more arms (16). An electrical connector for mounting on a circuit board (P) comprising: a housing (10), a plurality of lead terminals (20U) comprising projecting portions which at least partially project from the rear end of the housing (10), whereby the projecting portions comprise bent portions (22) at a distance from the housing (10) in which the lead terminals (20U) are and bent at an angle different from 0° or 180°, preferably substantially at right angles, in the direction of and to be connected with the circuit board (P) and base end portions (24U) extending substantially from the bent portions (22) to the connector housing (10), an alignment plate (30) for aligning the leading ends (23) of the lead terminals (20U), preferably by passing or inserting them in positioning holes (31) formed therein, characterized by displacement restricting means (32) being so provided as to project from the alignment plate (30) and the projecting end thereof engaging the base end portions (24U) of the lead terminals (20U) at a distance from the bent portions (22). A connector according to claim 7, wherein the alignment plate (30) is integrally mounted or mountable on the housing (10) by means of holding means (16), preferably comprising one or more arms (16). A connector according to claim 7 or 8, wherein the base end portions (24U) of the lead terminals (20U) are fitted into corresponding recesses (33) formed in the displacement restricting means (32). A connector according to claim 9, wherein the lead terminals (20U) are fitted into the corresponding recesses (33) such that frictional forces between inner walls (33A) of the recesses (33) are high enough to substantially prevent the base end portions (24) of the lead terminals (20U) from displacement in the corresponding recesses (33).

Inventors: ICHIDA KIYOFUMI, TOKUWA KOICHIRO, ICHIDA, KIYOFUMI, TOKUWA, KOICHIRO
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1998
Main classification: H01R12
IPC codes: H01R12, H01R13