Connector for a circuit board

Abstract: The invention is designed to assemble a connector with circuit board(s) with an improved degree of freedom. Directly connectable terminal fittings 12 and housing side terminals 13 are mounted on a housing 11. The housing 11 is mounted on a main circuit board 40, and the directly connectable terminal fittings 12 are inserted into through holes formed in the main circuit board 40 and soldered. An auxiliary circuit board 50 is disposed above the main circuit board 40 with the housing 11 therebetween. Board side terminals 14 mounted on the auxiliary circuit board 50 are connected with housing side terminals 13.

Description: The present invention relates to a connector to be assembled with a main circuit board and an auxiliary circuit board. The connector of this type includes a housing and terminal fittings pressed into the housing to be retained therein. One end of the terminal fittings projects into the housing and is brought into contact with mating terminals when the connector is engaged with a mating connector, and the other end of the terminal fittings is bent in L-shape. The other end is inserted into a terminal insertion hole formed in a circuit board when the housing is mounted on the circuit board, and then soldered with the circuit board. With the prior art connector, the terminal fittings carried by the housing are directly soldered with the circuit board on which the housing is mounted. Accordingly, it is impossible to detach the housing from the circuit board while leaving the portions soldered with the circuit board and/or to connect the terminals of the connector with another circuit board which is different from the one on which the housing is mounted. Thus, this connector can be used with a low degree of freedom. For example, when an electronic device is fabricated by mounting the connector of this type on a printed circuit board, another printed circuit board may be disposed above the printed circuit board mounted with the connector so that the connector is located between two printed circuit boards. In such a case, the terminals carried by the housing cannot be directly connected with the upper circuit board with the prior art connector. Accordingly, the terminals of the connector have to be connected with the upper circuit board by connecting the upper and lower circuit boards by means of a flat cables, a flexible printed circuit or like jumpers. This leads to an undesired increase in the number of circuits established by jumpers and an increased probability of picking up noises. US-A-4 475 781 discloses a bussing system for interconnecting pairs of circuit boards in closely spaced array of parallel spaced circuit boards and a pair of blade headers on each circuit board. The bussing system comprises a cabinet or chassis having a plurality of parallel spaced circuit board receiving channels and/ or grooves, and a series of plates or panels are mounted in the grooves intermediate the channels. Each plate has a bussing member on the free end thereof. Each circuit board has a first, low profile blade header and a second, high profile blade header mounted aligned on opposite sides of the same portion of a circuit board. The circuit board further has an IO connector at an edge portion thereof. Each header is provided with a plurality of terminals having one end in electrical contact with the circuitry of the circuit board and an opposite end projecting from the respective header. Each bussing connector will receive a header from a circuit board with the blades engaging the blade of the first profile header and the tine engaging the blade of the second profiled blade header. ADAMS G L: "Connectors for use with multiple PCBs" Motorola Technical Developments, vol. 11, 1. October 1990, pages 43-45, XP 000178615, discloses for a 2 and 3 PCB (printed circuit board) stack a construction of connectors consisting of one part containing the pins for each individual PCB plus one window to hold the assembly together. In view of the above problems, it is the object of the invention to provide a connector for being assembled with a main circuit board and an auxiliary circuit board which can be mounted on the circuit boards with an improved degree of freedom. This object is achieved by a connector according to claim 1. Preferred embodiments of the invention are subject of the dependent claims. According to a preferred embodiment of the invention, the housing side terminal and the board side terminal is provided with engaging means for the detachable connection, wherein the engaging means preferably comprises male and female connection portions and/or a connecting portion having a blade-shape and a connecting portion comprising a slot. Preferably the holding plate is at least partially fitted or arranged in a recess of the housing in an assembled state of the connector and wherein. the holding plate most preferably comprises at least one positioning slot and/or at least one positioning hole. According to a further preferred embodiment, the housing comprising preferably two or more, in particular similar housing parts. Preferably, the board side terminal and/or the terminal fitting is/are engagingly fitted in or integrally formed with the housing. According to a preferred embodiment of the invention there are provided terminal fittings mounted on the housing which are connectable with the main circuit board. Before the above connector is assembled with the main circuit board, the board side terminals are mounted on the main circuit board. As the housing carrying the housing side terminals is assembled with the main circuit board, the board side terminals and the housing side terminals are electrically connected. As described above, as the housing is assembled with the main circuit board, the board side terminals and the housing side terminals are electrically connected. Accordingly, the housing can be easily detached from the main circuit board, leaving the soldered portions, or the terminals of the connector can be easily connected with another circuit board different from the one on which the housing is mounted. Thus, the connector can be used with an improved degree of freedom. The connector further comprises a holder or holding plate for holding the board side terminals in such an alignment as they are mounted on the auxiliary circuit board. Accordingly , the board side terminals are held in advance by the holder in such an alignment as they are to be mounted on the auxiliary circuit board. The connector is assembled with the auxiliary circuit board in this state. Particularly, since the board side terminals are positioned by the holder, they can be easily and securely mounted on the auxiliary circuit board. Preferably, the holder plate is held between the auxiliary circuit board and the connector in an assembled state of the connector and the auxiliary circuit board. Accordingly, the holder is held between the auxiliary circuit board and the connector when the auxiliary circuit board and the connector are assembled, with the result that the auxiliary circuit board and the connector are made integral to each other via the holder. Further, since the auxiliary circuit board and the connector are made integral to each other via the holder, they can stably remain assembled. Hereafter, several embodiments of the invention are described with reference to FIGS. 1 to 8, wherein same reference numerals denote identical or similar parts. FIG. 1 is a partly exploded perspective view showing a state where a connector according to one embodiment of the invention is separated from one circuit board, FIG. 2 is a perspective view showing a state where the connector is mounted on a main circuit board, FIG. 3 is a section of an assembly of the connector and the circuit boards, FIG. 4 (a) is a perspective view of a second embodiment showing a state where the connector is mounted on a main circuit board, FIG. 4 (b) is a section of an assembly of the connector shown in FIG. 4 (a), FIG. 5 is a perspective view of a third embodiment of the invention, FIG. 6 is an exploded view of a fourth embodiment of the present invention. FIGS. 7 and 8 are perspectives view of the fourth embodiment shown in FIG. 6. A connector 10 for being assembled with a main circuit board and an auxiliary circuit board according to the invention is connected both with a main circuit board (lower circuit board in FIGS. 1 to 3) 40 and with an auxiliary circuit board (upper circuit board in FIGS. 1 to 3) 50. The connector 10 includes a housing 11 secured on the main circuit board 40, terminal fittings 12 directly connected with the main circuit board 40, housing side terminals 13 and board side terminals 14 to be connected with the auxiliary circuit board 50, and a holder or holding means or holding plate or positioning means 15 disposed between the housing 11 and the auxiliary circuit board 50. The housing 11 includes a pair of mount portions 16 each projecting outward from the bottom ends of its lateral side walls and formed with a positioning hole (not shown). The mount portions 16 are in flush with the bottom surface of the housing 11. The housing 11 is secured on the main circuit board 40 by a known means, e.g. by spirally fitting screws 17 inserted into the positioning holes into screw holes (not shown) formed in the main circuit board 40. The housing 11 is formed with a hood 18 having an opening at its front. A mating female housing is fittable into the hood 18. A plurality of terminal fitting mount holes 19 (6 in this embodiment) are formed side by side in the lateral direction of the housing 11, in particular in positions below the middle height thereof. The mount holes 19 extend from the rear end surface of the hood 18 to the rear end surface of the housing 11. Directly connectable terminal fittings 12 are pressed into the respective mount holes 19 to be secured in the housing 11. Each terminal fitting 12 has a known L-shaped structure including a tab 20 extending toward the opening of the hood 18 and a board connection portion 21 extending downward from the rear end of the tab 20 behind the housing 11. The tab 20 is engageable with a female terminal fitting (not shown) of a mating connector. When the housing 11 is mounted on the main circuit board 40, the leading end of the board connection portion 21 is inserted into a corresponding through hole 41 formed in the main circuit board 40 and then connected, e.g. soldered. The housing 11 is also formed with a plurality of cavities 23 (4 in this embodiment) opening and extending over the upper and rear surfaces of the housing 11 above the terminal fitting mount holes 19, and terminal fitting mount holes 24 extending from the front end surface of the respective cavities 23 to the rear end surface of the hood 18. A housing side terminal 13 used to connect the auxiliary circuit board 50 is mounted in each cavity 23. The housing side terminal 13 is formed by bending a metal plate of a specified shape, and includes a horizontally extending tab 25 and a connection portion 26 continuous or integrally connected with the rear end of the tab 25. The connection portion 26 includes a front plate 27, a rear plate 28 and a side plate 29 connecting the front and rear plates 27 and 28, and is U-shaped when viewed from above. The front and rear plates 27 and 28 of the connection portion 26 are formed with guide portions 30 defined by opposite walls which widen toward their upper ends, and engaging slots 32 continuous with the lower ends of the corresponding guide portions 30. The width of the slots 32 is set slightly smaller than the thickness of a connection portion 33 of a board side terminal 14. The housing side terminals 13 are integrally mounted on the housing 11 by pressing the tabs 25 into the mount holes 24. The front portions of the tabs 25 of the terminals 13 mounted on the housing 11 extend into the hood 18 in parallel with the tabs 20 of the terminal fittings 12 so as to be engageable with female terminal fittings (not shown) of the mating connector. The connection portions 26 are positioned in the corresponding cavities 23, and the guide portions 30 are aligned with the openings of the cavities 23 in the upper surface of the housing 11 so as to be ready to receive the board side terminals 14 to be described later. The board side terminals 14 are adapted to connect the housing side terminals 13 and the auxiliary circuit board 50. Each board side terminal 14 is made of a metal plate having a specified thickness, and includes a rectangular connection portion 33 engageable with the connection portion 26 of the housing side terminal 13, and a mount pin 34 projecting upward from the upper rear edge of the connection portion 33. The lower end of the connection portion 33 can be pressed into the engaging slots 31 of the connection portion 26 of the housing side terminal 13. Similar to the terminal fittings 12, the mount pins 34 are inserted into corresponding through holes 51 formed in the auxiliary circuit board 50 and e.g. soldered to be connected with a circuit (not shown) of the auxiliary circuit board 50. The board side terminals 14 are mounted on the auxiliary circuit board 50 before the connector 10 is assembled with the auxiliary circuit board 50. The holder 15 disposed between the housing 11 and the auxiliary circuit board 50 is made of a nonconductive material and has a width substantially same as that of the housing 11 and a specified thickness. The holder 15 is formed with a plurality of positioning slots 35 and a plurality of positioning holes 36 (four each in this embodiment). The positioning slots 35 are formed by cutting away the lower surface of the holder 15 so as to be engageable with the upper edges of the connection portions 33 of the corresponding board side terminals 14. The positioning holes 36 are through holes vertically extending at the rear ends of the positioning slots 35. The mount pins 34 of the housing side terminals 13 are inserted into the positioning holes 36. The positioning slots and holes 35 and 36 are aligned with the housing side terminals 13 mounted in the housing 11. Further, the alignment of the positioning holes 36 are same as that of the through holes 51 formed in the auxiliary circuit board 50. The board side terminals 14 are mounted on the holder 15 before being mounted on the auxiliary circuit board 50. The board side terminals 14 are mounted on the holder 15 by pressing the mount pins 34 into the positioning holes 36 from below and pressing the upper edges of the connection portions 33 into the positioning slots 35. With the board side terminals 14 mounted on the holder 15, the upper ends of the mount pins 34 project upward from the holder 15 by a distance longer than the thickness of the auxiliary circuit board 50, and the connection portions 33 project downward therefrom by a distance sufficient to be fitted into the engaging slots 31 of the housing side terminals 13. Next, it is described how the connector 10 of this embodiment is mounted on the main and auxiliary circuit boards 40 and 50. After the board side terminals 14 are integrally or unitarily mounted on the holder 15, this integral assembly is assembled with the auxiliary circuit board 50. With the board side terminals 14 mounted on the holder 15, the four mount pins 34 project from the holder 15 in parallel to one another and are so positioned as to be in alignment with the through holes 51 of the auxiliary circuit board 50. Accordingly, when the integral assembly is mounted on the auxiliary circuit board 50, the four mount pins 34 are simultaneously insertable into the through holes 51. This facilitates the assembling operation. The mount pins 34 are deeply inserted into the through holes 51 until their upper ends project upward from the auxiliary circuit board 50, thereby bringing the holder 15 into close contact with the lower surface of the auxiliary circuit board 50. In this state, the mount pins 34 are secured and/or connected on the auxiliary circuit board 50 e.g. by means of soldering (not shown), with the result that the holder 15, board side terminals 14 and auxiliary circuit board 50 are integrally assembled. After the terminal fittings 12 and the housing side terminals 13 are mounted on the housing 11, the housing 11 is assembled with the main circuit board 40 in advance. When the connector 10 is mounted on the main circuit board 40, the leading ends of the terminal fittings 12 are positioned and inserted into the through hole 41 of the main circuit board 40, and the housing 11 is secured on the main circuit board 40 by the screws 17. In this way, the connector 10 is completely mounted on the main circuit board 40, with the result that the terminal fittings 12 arranged at the lower stage of the housing 11 are connected with the main circuit board 40. Thereafter, the connector 10 is assembled with the auxiliary circuit board 50. During assembling, the auxiliary circuit board 50 is pressed against the connector 10 from above while the board and housing side terminals 14 and 13 are positioned with respect to each other. Then, the lower edges of the connection portions 33 of the board side terminals 14 are pressed into the engaging slots 31 by being guided by the tapered guide portions 30 of the housing side terminals 13, thereby completing the assembling. At this stage, the lower and upper surfaces of the holder 15 are in close contact with the upper surface of the housing 11 and the lower surface of the auxiliary circuit board 50, respectively. In this way, the housing 11 is assembled with the auxiliary circuit board 50 and the housing side terminals 13 arranged at the upper stage of the housing 11 are connected with the auxiliary circuit board 50 via the board side terminals 14. It should be appreciated that the main circuit board 40 is secured by screws on a mount portion formed in a unit box (not shown) for housing the connector 10 and the main and auxiliary circuit boards 40 and 50, and that the auxiliary circuit board 50 is also secured on another mount portion in the unit box. Since tapered guide portions are formed in the housing side terminals 13, it is unnecessary or not indispensable to accurately position the connection portions 26, 33 with respect to each other in the lateral direction. Further, since the connection portions 26 of the housing side terminals 13 are hollow in their forward/backward direction, it is unnecessary to accurately position the connection portions 26, 33 with respect to each other in the forward/backward direction. Thus, the connection can be easily and securely made even if the engagement of the connection portions 26, 33 cannot be visually confirmed. The terminal fittings 12 mounted on the connector 10 are directly connected with the circuit of the auxiliary circuit board 50 without using a flat cable. This obviates the need for an operation of connecting a flat cable with the both circuit boards. In other words, a working efficiency is improved by reducing the number of necessary operations. If necessary, the main and auxiliary circuit boards 40 and 50 may be connected using a flat cable and a flexible printed circuit board as jumpers. Since the connector 10 is directly connected with the auxiliary circuit board 50 even in such a case, the number of circuits established by the jumpers can be reduced. Accordingly, by eliminating the jumper connection or reducing the number of circuits established thereby, a space for arranging the flat cable or flexible printed circuit board can be reduced. Consequently, the final assembly can be made smaller. Since the connector 10 and the auxiliary circuit board 50 are connected by engagement of the connection portions 26 of the housing side terminals 13 and the connection portions 33 of the board side terminals 14, they can be easily separated. Accordingly, if either one of the connector 10 and the auxiliary circuit board 50 experiences an abnormality, these two elements are separated, and only the element experiencing an abnormality is replaced while the remaining normal element still remains in use. Thus, a maintenance cost can be reduced. Further, if there are prepared, e.g. a plurality of kinds of auxiliary circuit boards 50 having different functions, the function of the device can be changed only by changing the auxiliary circuit board 50. Thus, a multitude of kinds of devices can be manufactured while using as many parts as possible in common. Further, in this embodiment, since the holder 15 is closely held between the connector 10 and the auxiliary circuit board 50, the connector 10 and the auxiliary circuit board 50 do not move toward each other even if an upward or downward acting external force is exerted on them. Accordingly, the connected portions of the board side terminals 14 with the auxiliary circuit board 50 and the engaged portions of the housing side terminals 13 and the board side terminals 14 are not damaged due to the movement of the connector 10 and the auxiliary circuit board 50 with respect to each other. Therefore, these elements can remain properly connected and engaged. The holder 15 also acts to position and align the mount pins 34 of the board side terminals 14 with respect to the through holes 51 of the auxiliary circuit board 50. Thus, the board side terminals 14 can be easily and securely connected with the auxiliary circuit board 50. The invention is not limited to the described and illustrated embodiment. For example, the following embodiments are embraced by a technical scope of the invention. Besides the following embodiments, the invention can be embodied in a variety of manners without departing from the scope of the invention as defined in the claims. (1) In the foregoing embodiment, the main circuit board 40 is connected with the connector 10 using the directly connectable terminal fittings 12 while the auxiliary circuit board 50 is connected therewith using the board side terminals 14 and the housing side terminals 13. However, according to the invention, both circuit boards 40, 50 may be connected with the connector 10 using the board side terminals 14 and the housing side terminals 13. (2) In the foregoing embodiment, the board side terminals 14 and the housing side terminals 13 are pressingly engaged. However, a spring member may be provided in one or both of the terminals, and the terminals may be engaged taking advantage of an elastic force of the spring member. (3) In the foregoing embodiment, the board side terminals 14 and the housing side terminals 13 have male and female connection portions, respectively. However, the shapes of the connection portions are not limited to the above. For example, the board side terminals 14 may have female connection portions while the housing side terminals 13 have male connection portions. Alternatively, the terminals 14 and 13 may have connection portions of other shapes. (4) Although the connector 10 is assembled with two circuit boards 40, 50 in the foregoing embodiment, the invention is applicable to an assembly in which a connector is assembled with more than two circuit boards. (5) The numbers of the terminal fittings 12, 13 mounted on the connector 10 are not limited to those described in the foregoing embodiment. The invention is applicable to any connector for a circuit board on which any desired number of terminal fittings are mountable. A second embodiment of the invention is described with reference to FIGS. 4 (a) and (b). The second embodiment is similar to the first embodiment with the exception that the housing 11 is provided with a housing recess 11r for accommodating or fitting the holder 15 in or into the housing 11. Thus the auxiliary board 50 can be located more closely to the housing 11 whereby the volume of the whole connector can be reduced. The holder 15 may be preferably provided with a holder recess 15r on the front portion thereof. When the holder 15 is located in or inside the housing recess 11r of the housing 11 as shown in FIG. 4 (b), the holder recess 15r flushes with the hood 18 thus allowing a good insertion of mating connectors into the connector 10. A third embodiment of the invention is described with reference to FIG. 5. Board side terminals 14 are in particular fixedly mounted via holders 15 on the first or auxiliary board 40 and on the second or main board 50. The housing 11 of the connector is provided with housing side terminals 13 being similar in construction to those of the preceding embodiments and allowing for an insertion of the connection portions of the mating board side terminals 14 from a longitudinal direction (i.e. the direction along the horizontally extending tab 25) and/or a lateral direction. The housing 11 can be in particular laterally inserted between the main board 40 and the auxiliary board 50, thereby connecting the board side terminals 14 and the housing side terminals 13 and creating an electrical contact between them. The housing is preferably provided with two housing recesses 11r on the surfaces facing the holders 15 and the holders 15 are provided with holder recesses 15r in the front portion thereof in a similar way as in the second embodiment. A fourth embodiment of the invention is described with reference to FIGS. 6 and 7. The connector according to the fourth embodiment is similar to the connector according to the first embodiment shown in FIG. 1 with the exception that the housing 11 of the connector is divided in a first, in particular upper housing part 11a and a second, in particular lower housing part 11b. The first housing part 11a and the second housing part 11b are provided with housing/side terminals 13, wherein the housing-side terminals 13 of the first housing part 11a and the housing-side terminals 13 of the second housing part 11b are oriented in a symmetric way with respect to the dividing line or plane of the two housing parts 11a and 11b. The housing parts 11a and 11b are in particular similar and can be provided with locking means (not shown) which may lock the two parts 11a and 11b together or joined. When the two housing parts 11a and 11b are joined the horizontally extending tabs 25 of the housing-side terminals 13 of the housing parts 11a and 11b are spaced such, that female terminal fittings of a single mating connector (not shown) can be inserted or connected contemporarily from a front portion thereof. Furthermore the housing parts 11a and 11b are formed such that a hood 18 (see FIG. 7) similar to that of the preceding embodiments is formed between the in a joined state. The housing parts 11a and 11b may be first joined and then connected with the respective auxiliary and main boards 50 and 40 (FIG. 7) or first connected to the respective auxiliary and main boards 50 and 40 and then joined together (FIG. 8).

Claims: A connector for being assembled with a main circuit board (40) and an auxiliary circuit board (50), comprising: a housing (11) mountable on the main circuit board (40), and at least one board side terminal (14) connectable with the auxiliary circuit board (50), characterized in that , a holding plate (15) is arranged between the auxiliary circuit board (50) and the housing (11) and having a first surface engaged against the auxiliary circuit board (50) and an opposed second surface against the housing (11) for holding the board side terminals (14) in a predetermined orientation, wherein the housing (11) is formed with at least one cavity (23) for receiving a connection portion (33) of the board side terminal (14) and wherein at least one housing side terminal (13) is secured to the housing (11) and detachably connected to the connection portion (33) of said board side terminal (14) A connector according to claim 1, wherein the housing side terminal (13) and/or the board side terminal (14) is provided with engaging means (27, 28, 30, 33) for the detachable connection. A connector according to claim 2, wherein the engaging means (27, 28, 30, 33) comprises male and female connection portionsand/or a connecting portion (33) having a blade-shape and a connecting portion (27, 28) comprising a slot (30). A connector according to one or more of the preceding claims, wherein a terminal fitting (12) is fixedly connectable with the main circuit board (40), and in particular the terminal fitting (12) is engagingly fitted in or integrally formed with the housing (11). A connector according to one or more of the preceding claims, wherein the holding plate (15) is at least partially fitted in a recess (11r) of the housing (11) in an assembled state of the connector (10). A connector according to one or more of the preceding claims, wherein the holding plate (15) comprises at least one positioning slot (35) and/or at least one positioning hole (36). A connector according to claim 6, wherein the board side terminal (14) having a mount portion (34) extending through the positioning hole (36) of the holding plate (15). A connector according to one or more of the preceding claims, wherein the housing (11) comprising two or more, in particular similar housing parts (11a, 11b). A connector according to one or more of the preceding claims, wherein. the board side terminal (13) is engagingly fitted in or integrally formed with the housing (11). A connector according to one or more of the preceding claims, wherein said connection portion (33) of said board side terminal (14) projecting from the surface of the holding plate (15).

Inventors: AOYAMA MASAHIKO, AOYAMA, MASAHIKO, AOYAMA, MASAHIKO, C/O SUMITOMO WIRING SYSTEMS, LTD
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1996
Main classification: H01R12
IPC codes: H01R13, H01R12