BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a vertical cross section showing a low profile connector according to one embodiment of the present invention;
FIG. 1B is a vertical cross section showing a connector plug according to one embodiment of the invention;
FIG. 2A is a side elevation showing two kinds of contacts of the low profile connector;
FIG. 2B is an explanatory view showing an arrangement of pads on a printed circuit board;
FIG. 3 is a fragmentary vertical cross section showing a state in which the low profile connector and the connector plug are fitted together;
FIG. 4 is a vertical cross section showing a state in which the low profile connector is used;
FIG. 5 is a vertical cross section showing deformation of contacts caused when the low profile connector is being withdrawn in a case where reinforcing protrusions of the connector are soldered to a printed circuit board;
FIG. 6 is a vertical cross section similar to FIG. 5 but in which the reinforcing protrusions are not soldered to the printed circuit board;
FIG. 7A is a vertical cross section of a connector receptacle over which a connector plug is fitted, the plug and receptacle being designed by one prior art technique;
FIG. 7B is a perspective view showing the manner in which the connector receptacle and the connector plug shown in FIG. 7A are fitted together;
FIG. 8 is a vertical cross section showing the manner in which the connector receptacle and the connector plug shown in FIGS. 7A and 7B are in an incompletely locked state; and
FIG. 9 is a vertical cross section showing deformation of the neck portion of each contact when the connector plug shown in FIGS. 7A, 7B, and 8 is withdrawn from the connector receptacle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1A, a low profile connector according to the present invention is generally indicated by reference numeral 1 and is a low profile connector receptacle mounted on a printed circuit board 4. The connector receptacle 1 has plural contacts 2 juxtaposed with each other. The contacts 2 come into contact with the surface of the printed circuit board 4 on which the receptacle 1 is mounted.
Each of the contacts 2 is composed of a base portion 2a1 or 2a2 firmly fixed to an insulating housing 3 of the connector receptacle 1 and electrically connected with the printed circuit board 4, a neck portion 2b extending from the base portion 2a1 or 2a2 along the surface 4a of the printed circuit board, and a touch portion 2c raised from the neck portion 2b relative to the surface 4a of the printed circuit board. The touch portion 2c is in resilient contact with a contact 5 of a connector plug 6 shown in FIG. 1B and electrically connected with the contact 5.
As shown in FIG. 2A, the neck portion 2b of each contact 2 located between the base portion 2a1 or 2a2 and a touch portion 2c has a reinforcing protrusion 2d1 or 2d2 that is abutted against the surface 4a of the printed circuit board. Because a distance L3 between the base portion 2a1 and the touch portion 2c is smaller than a distance L1 between the touch portion 2c and the base portion 2a2, the reinforcing protrusion 2d1 of the base portion 2a1 is mechanically strong. Therefore, during withdrawal, if the contact is pulled upward, it is less deformed. Consequently, the contact is not bonded to the printed circuit board 4 by soldering.
On the other hand, the reinforcing protrusion 2d2 of the base portion 2a2 is easily bendable because the distance L1 between the base portion 2a2 and the touch portion 2c is very large. During withdrawal, when the contact is pulled upward, it is deformed greatly. Therefore, as shown in FIG. 2B, pads “c” are mounted on the printed circuit board 4 and the contact is firmly mounted by soldering.
The contacts 2 are arranged at a reduced pitch in the direction of array as indicated by the arrows in FIG. 2B. Therefore, pads “a” and “b” are arranged in a zigzag pattern in the direction of array of the contacts 2, and the base portions 2a1 and 2a2 are arranged in a zigzag pattern, to prevent the pads on the printed circuit board 4 to which the base portions 2a1 and 2a2 are soldered from being located too closely; otherwise, the solder would bridge between the adjacent pads. The pads “a” correspond to the base portion 2a2. The pads “b” correspond to the base portion 2a1.
In this way, with respect to the reinforcing protrusions 2d1 and 2d2, alternate ones of the reinforcing protrusions 2d2 of the adjacent contacts 2 of the profile connector 1 where the plural contacts 2 are arranged parallel to each other as shown in FIG. 2A are firmly bonded to the printed circuit board. As shown in FIG. 3, indicated by 2e in the contact 2 is fixing portions to be mounted with a press fit into the housing 3. The connector plug 6 has a touch portion 5c that makes contact with the contact 5. The plug 6 also has a stationary portion 5e.
Where the low profile connector 1 constructed as described so far is used, as shown in FIG. 4, when the connector plug 6 is mounted, for example, to the low profile connector 1 mounted on the printed circuit board 4, the touch portions 2c of the contacts 2 make sliding contact with the touch portions 5c of the mating contact 5 and are pushed downward. The reinforcing protrusions 2d1 and 2d2 bear against the surface 4a of the printed circuit board, and a reaction force can be obtained. The intensity of resistance to deformation of the contacts 2 is increased. The amount of deformation is reduced. The state of fitting is improved. Furthermore, the protrusions 2f and 5f with which the contacts 2 and 5 come into contact pass over each other in the direction of movement for achieving fitting. Consequently, a good feeling of clicking is obtained.
In addition, as shown in FIG. 5, the protrusions 2f and 5f of the connector receptacle 1 and connector plug 6 are in abutment with each other in the direction of withdrawal. Since the strength of the neck portions 2b of the contacts 2 are reinforced, the contacts 2 and 5 are less likely to be disengaged from each other even when dropped.
Where the connector plug 6 is withdrawn, as shown in FIG. 5, with respect to the contact 2 whose reinforcing protrusion 2d2 is soldered to the printed circuit board 4, the distance to the touch portion 2c is small. The strength of the resistance to deformation is large. Accordingly, the amount of upward flexure is small and the amount of deformation is small. On the other hand, as shown in FIG. 6, with respect to the contact 2 whose reinforcing protrusion 2d1 is not soldered to the printed circuit board 4, if the protrusions 2f and 5f of the touch portions 2c and 5c bear against their mating members during withdrawal, the neck portion 2b is raised upward. Since the distance L6 between the base portion 2a1 and the touch portion 2c is relatively small, excessive deformation does not take place. Also, in this case, the protrusions 2f and 5f pass over each other in the direction of withdrawal, and a feeling of clicking is obtained.
Patent Application
20080026609
