The present invention relates to a surface mount connector. In particular, the present invention relates to a surface mount connector capable of suitably doing with flux when the surface mount connector is attached to a circuit board with solder.
A conventional apparatus such as a cellar phone includes a coaxial connector with a switch. A coaxial connector with a switch can inspect circuit characteristics of a device by switching a signal path in the device with the switch.
Patent Reference has disclosed an example of the conventional coaxial connector of this type. The coaxial connector disclosed therein is mounted on an inner circuit board of a device with solder through a reflow treatment. In the process of soldering, flux contained in cream solder may enter the coaxial connecter upon soldering through a capillary phenomenon in some cases. In order to prevent flux from entering, the conventional coaxial connector has a groove in a direction orthogonal to a direction that flux enters, thereby preventing flux from entering and a contact failure of a terminal of the coaxial connector.
Patent Reference: Japanese Patent Publication No. 2001-176612
In the conventional coaxial connector described above, the groove is provided in a housing in the direction orthogonal to the direction that flux enters. Accordingly, it is difficult to completely guide flux into the groove, thereby making it difficult to fully prevent flux from entering into an inappropriate section such as a contact section. In addition, the groove has a size large enough so as not to cause a capillary phenomenon. Accordingly, it is difficult to securely hold flux.
In view of the problems described above, an object of the present invention is to provide a surface mount connector capable of solving the problems of the conventional connector. In the surface mount connector, it is possible to properly guide flux, thereby securely preventing flux from entering an undesired portion. Further, it is possible to hold flux upon generation thereof, thereby securely preventing flux from entering.
In the specification, flux is not limited to flux itself, and may include a substance such as a mixture of flux and solder that may enter upon soldering and cause contact failure.
Further objects and advantages of the invention will be apparent from the following description of the invention.
In order to attain the objects described above, according to the present invention, a surface mount connector includes a housing and a movable terminal attached to the housing. The movable terminal includes a movable section to be movable relative to the housing; an adhering section connected to the movable section for forming an adhering surface relative to the housing; and a connecting section connected to the adhering section via a joining section and to be connected with soldering.
The adhering surface has a groove extending toward the movable section. The movable terminal has an opening portion connected to the groove provided in a crossing direction crossing a direction that the adhering section is connected to the movable section and having a width larger than that of the groove.
In the surface mount connector of the invention, the opening portion may extend toward the movable section in the direction that the adhering section is connected to the movable section.
In the surface mount connector of the invention, the groove may have a width on a side of the joining section in the crossing direction larger than that of the joining section near the groove.
In the surface mount connector of the invention, the opening portion may be provided at one of a rear end of the groove and a middle portion of the groove.
In the surface mount connector of the invention, a plurality of the grooves may be provided and connected to each other via the opening portion. It may be possible to reduce a depth of the grooves, thereby reducing the number of the grooves.
In the surface mount connector of the invention, a space may be provided above the opening portion provided in the movable terminal.
The surface mount connector of the invention may be a coaxial connector with a switch. The surface mount connector may include a stationary terminal secured in the housing and the movable terminal paired with the stationary terminal.
According to the invention, the groove securely guides flux generated due to reflow upon soldering, so that it is possible to prevent flux from entering beyond a specified position.
Hereunder, embodiments of the present invention will be described referring to the accompanying drawings.
In the embodiment, the coaxial connector 1 with a switch includes an insulating housing 2 made of a resin; a set of a stationary terminal 3 and a movable terminal 4 attached to the housing 2; and an outer conductor 7 made of a metal to cover the housing 2 from outside. The coaxial connector 1 is used for inspecting circuit characteristics of an electronic device such as a cellular phone by switching a signal path in the electronic device using a terminal switch formed of the stationary terminal 3 and the movable terminal 4.
In an actual use, the coaxial connector 1 is mounted on a board (not illustrated) in the electronic device by soldering. When the coaxial connector 1 is used for inspection, an inspection needle (not illustrated) is inserted from thereabove, and the stationary terminal 3 and the movable terminal 4 are switched between a contacted state and a non-contacted state.
In the embodiment, the insulating housing 2 includes a substantially circular cylindrical main body 8; a relatively thin protruding section 9 and a relatively thick protruding section 10, which respectively protrude outward under the main body 8; and a bottom plate 15. In order to easily insert the inspection needle, the main body 8 may have an inverted conical recess 11 at a center part of an upper surface thereof.
In the embodiment, a hollow section 14 is formed between the thin protruding section 9 and the thick protruding section 10, and the bottom plate 15. A connecting hole 16 is provided along the axial direction between the recess 11 and the hallow section 14. The hallow section 14 is provided so as to connect to outside through a lateral hole 18 for inserting the stationary terminal 3 provided in the protruding section 9 and a lateral hole 20 for inserting the movable terminal 4 provided in the protruding section 10.
Further, a lower groove 19 that extends parallel to the lateral hole 18 and has a narrower width than that of the lateral hole 18 is formed in a side face of the bottom plate 15 on a side of the protruding section 9. A lower groove 21 that extends parallel to the lateral hole 20 and has a narrower width is provided in a side face of the bottom plate on a side of the protruding section 10.
As shown in
In the embodiment, the joining section 24 is a curved section having a smaller width than that of the securing section 23 for joining the securing section 23 and the connecting section 25, and is provided while having a space against a side face of the bottom plate 15. The connecting section 25 is a flat section that extends horizontally in the same direction and has the same width as that of the joining section 24. The connecting section 25 is provided on the bottom plate 15 while being received in the lower groove 19. In an actual use, the connecting section 25 is secured on a specified circuit (not illustrated) by soldering.
In the embodiment, the movable terminal 4 includes a movable section 26; securing sections (adhering sections) 27; a joining section 28; and a connecting section 29 in this order while being formed continuously to each other. The movable section 26 is a narrower flat section that is slightly biased upward, and has a slightly sharp end 39. The movable section 26 can move relative to the insulating housing 2 and the stationary terminal 3.
Upon insertion into the lateral hole 20, the movable section 26 is inserted in the lateral hole 20, more specifically, in a narrow upper hole 20′ thereof. Upon insertion in the upper hole 20′, the sharp end 39 of the movable section 26 elastically contacts with the lower contact point 30 provided on the securing section 23 of the stationary terminal 3.
When the sharp end 39 is displaced downward (in an arrow direction a in
In the embodiment, the stationary section 27 is a wide flat section that extends horizontally, and is pressed in the lateral hole 20, more specifically, a wide lower hole 20″ thereof, using the protrusion 32 (refer to
In the embodiment, the joining section 28 is a curved section having a smaller width than that of the movable terminal 26 for joining between the securing section 27 and the connecting section 29. The joining section 28 is attached while having a relatively large space 42 against the side face 83 of the bottom plate 15. The connecting section 29 is a flat section that extends horizontally in the same direction as that of the securing section 27 and has the same width as that of the joining section 28. The connecting section 29 is attached onto the bottom plate 15 while being received in the lower groove 21. In an actual use, the connecting section 29 is connected to a specific circuit (not illustrated) on a board by soldering.
In the embodiment, the outer conductor 7 is formed of a sheet metal. The outer conductor 7 essentially includes a circumferential wall 49 and legs 57 and 58 having the same shape. The circumferential wall 49 is a cylindrical section that covers the main body 8 of the insulating housing 2 from the outside. In order to maintain the contact with the inspection needle, the circumferential wall may have an annular grove 59 therearound. The legs 57 partially cover the upper sections 33 and 34 of the protruding sections 9 and 10 and a side face 37 of the insulating housing 2, and are bent to fit step-like section 45 at the end section 47 and secured thereon. The legs 57 are formed being cut at a center part thereof so as to be divided.
Similarly to the legs 57, the legs 58 partially cover the upper sections 33 and 34 of the protruding sections 9 and 10 and side face 37 of the insulating housing 2, and are bent to fit the step-like section 45 at the end section 47 and secured thereon. The outer conductor 7 is connected to a ground circuit on the board (not illustrated) by soldering at the bottom face of the edges 47 and 48.
Referring to
When the flux reaches the movable section 26, the movable section 26 may have a problem in spring characteristics. Further, an electrical contact between the movable section 26 and the stationary terminal 3 may be failed. Accordingly, it is necessary to prevent the flux from reaching the movable section 26 through the capillary phenomenon.
While the problems due to the capillary phenomenon may be related to the movable terminal 4, there is no such problem related to the stationary terminal 3. This is because, even when the flux crawls up through the space 41, the flux would not reach the securing section 23 due to the space 70 under the securing section 23.
In order to solve the problem related to the flux crawling up through the capillary phenomenon, the housing 2 has grooves 60 to guide the flux toward the movable section 26 through the capillary phenomenon. Each of the grooves 60 extends along an adhering surface between the securing section 27 and the upper surface 36 of the bottom plate 15 in a direction connecting the securing section 27 and the movable section 26 (in an arrow direction b in
In the embodiment, the housing 2 has two grooves 60A and 60B having the same shape and size. The grooves 60A and 60B are also fully illustrated in
In the embodiment, the flux can be guided (controlled) toward the movable section 26 along the grooves 60. Accordingly, it is possible to prevent the flux from flowing through the capillary phenomenon along the adhering surface between the securing section 27 and the upper face 36 of the bottom plate 15 except the grooves 60. Further, when the lateral hole 20 is formed in the insulating housing 2, a rod-like section having a semicircular section corresponding to a sectional shape of the grooves 60 is disposed in a mold (not illustrated), thereby making it possible to easily form the grooves 60. The rod-like section may be also useful for increasing the strength of the mold.
In the embodiment, the movable terminal 4 has a hole 61 being connected to the grooves 60 along a direction (an arrow direction c in
In the embodiment, the hole 61 is provided at the respective rear end positions of the grooves 60A and 60B while joining the grooves 60A and 60B to each other. It is not necessary to provide the holes 61 at the rear end positions. For example, grooves 60′ shown with a hidden line may be provided. In the grooves 60′, a length thereof in the direction b increases, and the hole 61 is provided in the middle of the grooves 60′.
Further, it is not necessary to provide the hole 61 so as to join the grooves 60A and 60B to each other, and the hole 61 can be independently provided in the grooves 60A and 60B. With the hole 61, the groove 60 is opened, so that it is possible to stop the flux and securely hold the flux or solder in the hole 61 when an amount of the flux, the solder, etc. is too large.
In the embodiment, the hole 61 may have an extended section 62 with a T character shape relative to the groove 60, and the extended section 62 extends toward the movable section 26. With the extended section 62, it is possible to increase a volume of the opened portion of the groove 60 and also to improve the spring characteristics of the movable terminal 4.
Furthermore, with the extended section 62, the plate width is changed, so that a stress applied on the movable terminal 4 near a boundary between the movable section 26 and the securing section 27 is dispersed, thereby reducing stress concentration.
As shown in
Furthermore, a space 66 (refer to
In the embodiment described above, the coaxial connector with a switch is explained as an example. In addition to the coaxial connector, the present invention can be widely applied to various types of connectors having movable terminals. Therefore, the invention shall not be limited to the application in the coaxial connector with a switch.
In the embodiment described above, the movable terminal 4 has the grooves 60, and the housing 2 may have similar groove. Two grooves 60 are provided, and the number of the grooves 60 can be adjusted as far as the grooves 60 have enough capacity to guide the flux. For example, when the depth of the groove 60 (the width j shown in
The disclosure of Japanese Patent Application No. 2007-208136, filed on Aug. 9, 2007, is incorporated in the application by reference.
While the invention has been explained with reference to the specific embodiments of the invention, the explanation is illustrative and the invention is limited only by the appended claims.
Number | Date | Country | Kind |
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2007-208136 | Aug 2007 | JP | national |