Cap and connector unit

A cap which is made difficult to come off a connector by suppressing deformation of the cap. The cap includes an insertion portion that has a hollow cylindrical shape and is inserted in a shell body of a shell of a receptacle connector, and a cover portion which is continuous with the insertion portion and covers an opening of the shell body. Ribs are formed inside the insertion portion, for suppressing deformation of the insertion portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a cap and a connector unit including the cap.

2. Description of the Related Art

As a conventional cap which is mounted on a connector, there has been proposed one disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2002-124339. A receptacle connector is disposed on a printed circuit board in a state in which an opening of a fitting portion thereof is directed up, and hence it is not possible to attract the receptacle connector by a mounter. To make it possible to attract the receptacle connector by the mounter, a cap is removably mounted on the fitting portion.

The cap disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2002-124339 is mounted on an outer periphery of an upper portion of the fitting portion in a manner covering the opening of the fitting portion.

As another conventional cap, there has been proposed a cap which is comprised of an insertion portion having a hollow cylindrical shape, which is inserted in a fitting portion of a receptacle connector, and a cover portion which covers an opening of the fitting portion. The insertion portion and the cover portion are integrally formed of a resin.

Further, a receptacle connector of a certain type includes a locking spring for preventing a plug connector from coming off. A front portion of the locking spring protrudes into a fitting portion of the receptacle connector. When the plug connector is fitted to the receptacle connector including the locking spring, the locking spring of the receptacle connector is engaged with a hole of the plug connector, whereby the plug connector is locked to the receptacle connector.

If the cap is mounted on the receptacle connector, it is possible to attract the receptacle connector by the mounter via the cap, to thereby dispose the receptacle connector on a predetermined position on the printed circuit board. It should be noted that when the cap is mounted on the receptacle connector, the locking spring of the receptacle connector presses the outer peripheral surface of the insertion portion of the cap, whereby the cap is positively held by the receptacle connector.

The printed circuit board on which the receptacle connector is disposed is conveyed to a reflow furnace, and the receptacle connector is soldered to the printed circuit board.

However, since the cap is made of a resin, if the cap is heated in the reflow furnace, the cap is liable to be deformed, and further, in a case of a connector provided with a locking mechanism, the stress of the locking spring is applied to the outer peripheral surface of the insertion portion of the cap, and hence the cap is further deformed.

As a consequence, for example, when the printed circuit board is conveyed after the receptacle connector is soldered thereto, or when the printed circuit board is inverted upside down to mount other electronic components on a surface opposite to a surface on which the receptacle connector is mounted, there is a case where the cap falls off the receptacle connector.

SUMMARY OF THE INVENTION

The present invention has been made in view of these circumstances, and an object thereof is to provide a cap which is made difficult to come off a connector by suppressing deformation of the cap, and a connector unit including the cap.

To attain the above object, in a first aspect of the present invention, there is provided a cap for being removably mounted on a fitting portion of a connector that receives a mating connector, comprising an insertion portion that has a hollow cylindrical shape, and is inserted into the fitting portion, a cover portion that is continuous with the insertion portion, and covers an opening of the fitting portion, and a reinforcing portion that suppresses deformation of the insertion portion.

With the arrangement of the cap according to the first aspect of the present invention, deformation of the insertion portion is suppressed by the reinforcing portion, whereby the cap is made difficult to come off the connector.

Preferably, the reinforcing portion is formed on an inner peripheral surface of the insertion portion at a location corresponding to a location on an outer peripheral surface of the insertion portion where a spring piece formed on the fitting portion is engaged.

Preferably, the spring piece is a locking spring piece for locking the mating connector.

To attain the above object, in a second aspect of the present invention, there is provided a connector unit, comprising a connector including a fitting portion that receives a mating connector, and a cap removably mounted on the fitting portion, the cap including an insertion portion that has a hollow cylindrical shape, and is inserted into the fitting portion, a cover portion that is continuous with the insertion portion, and covers an opening of the fitting portion, and a reinforcing portion that suppresses deformation of the insertion portion, the fitting portion having a spring piece for being engaged with an outer peripheral surface of the insertion portion, the reinforcing portion being formed on an inner peripheral surface of the insertion portion at a location corresponding to a location on the outer peripheral surface of the insertion portion where the spring piece is engaged.

With the arrangement of the connector unit according to the second aspect of the present invention, the fitting portion includes the spring piece which is engaged with the outer peripheral surface of the insertion portion, and hence the urging force of the spring piece acts on the outer peripheral surface of the insertion portion, whereby the cap is positively held by the connector. Further, since the reinforcing portion is formed on the inner peripheral surface of the insertion portion at a location corresponding to a location on the outer peripheral surface of the insertion portion where the spring piece is engaged, as described above, the reinforcing portion receives the returning force of the spring piece, whereby deformation of the cap is positively suppressed.

Preferably, the spring piece extends in a connector fitting direction, and a front end portion of the spring piece is located in the vicinity of the opening of the fitting portion.

Preferably, the spring piece is a locking spring piece for locking the mating connector.

According to these preferred embodiments, deformation of the cap is suppressed, whereby the cap is made difficult to come off the connector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described in detail with reference to the drawings showing preferred embodiments thereof.

Referring toFIGS. 1,2,3, and6, a connector unit1is comprised of a receptacle connector3and a cap9.

Referring toFIGS. 4,5, and7, the receptacle connector3includes a housing4, contacts5and5′, and a shell6. The receptacle connector3is a connector of the standard of HDMI (High-Definition Multimedia Interface).

The housing4is integrally formed of a synthetic resin, and includes a bottom board portion41, a contact-arranging portion42. The bottom board portion41is substantially plate-shaped. The contact-arranging portion42is substantially plate-shaped, and is perpendicularly continuous with the bottom board portion41. The contact arranging portion42has a front surface (surface on the left side of the contact arranging portion42as viewed inFIG. 5) and a rear surface (surface on the right side of the contact arranging portion42as viewed inFIG. 5) both formed with grooves42aat equally-spaced intervals. The grooves42ain the front surface of the contact arranging portion42and the grooves42ain the rear surface of the contact arranging portion42are displaced by half a pitch in the direction of arrangement of the grooves42a.

Each of the contacts5includes a contact portion51, a terminal portion52, and a connecting portion (not shown). Each contact5is formed by blanking and bending a metal plate having conductivity and elasticity. The contact portion51is accommodated in an associated one of the grooves42ain the front surface of the contact arranging portion42. The surface of the contact portion51protrudes from the associated groove42a. The contact portion51is brought into contact with a contact portion of an associated one of contacts of a mating connector, not shown. The terminal portion52is bent at a substantially right angle, and a front end portion thereof protrudes forward (leftward as viewed in FIG.5) from the housing4. The terminal portion52is soldered to a pad on a printed circuit board, not shown. The connecting portion connects between the contact portion51and the terminal portion52. The connecting portion is press-fitted into an associated one of holes41aformed in the bottom board portion41of the housing4.

Each of the contacts5′ includes the contact portion51, the terminal portion52, and the connecting portion, not shown, and has substantially the same shape and size as those of each contact5. A difference between each contact5′ and each contact5is that the connecting portion of the contact5′ is longer than that of the contact5. The terminal portion52of the contact5′ protrudes forward from the housing4, similarly to the terminal portion52of the contact5. Therefore, the terminal portions52of the contacts5and the terminal portions52of the contacts5′ are arranged in an alternating manner on a front side of the receptacle connector3(left side of the receptacle connector3as viewed inFIG. 5). The contact portion51of each contact5′ is accommodated in an associated one of the grooves42aof the rear surface of the contact arranging portion42. The surface of the contact portion51of each contact5′ protrudes from the associated groove42a. The connecting portion is press-fitted in an associated one of the holes41aformed in the bottom board portion41of the housing4.

As shown inFIGS. 1,2,3,5, and7, the shell6includes a shell main body (fitting portion)61, and through hole terminals62. The shell main body61has a substantially hollow cylindrical shape, and a transverse cross-section (cross-section along a direction orthogonal to a fitting/removing direction D1(seeFIG. 7) to/from the mating connector) has a substantially D shape. The shell6is formed by blanking and bending a metal plate having conductivity and elasticity.

The shell main body61has a rear surface formed with two locking spring pieces (spring piece)611. The locking spring pieces611extend in the fitting/removing direction D1. Each locking spring piece611is capable of being elastically deformed in a direction of a thickness thereof. A front end portion611aof each locking spring piece611is bent into a substantially L-shape. The front end portion611aprotrudes into the shell main body61, and is engaged with an associated one of holes (not shown) of a shell of the mating connector which is inserted into the shell main body61, to thereby lock a fitting portion of the mating connector.

The shell main body61has a front surface formed with two contact spring pieces612. The contact spring pieces612extend in the fitting/removing direction D1(seeFIGS. 1 and 7). Each contact spring piece612is capable of being elastically deformed in a direction of a thickness thereof. A front end portion612aof each contact spring piece612is bent into a substantially L-shape. The front end portion612aof each contact spring piece612protrudes into the shell main body61, and is brought into contact with the shell of the mating connector which is inserted into the shell main body61.

The through hole terminals62are continuous with a lower end of the shell main body61, and extend in the fitting/removing direction D1. Each of the through hole terminals62is soldered to an associated one of through holes in the printed circuit board. As a result, the shell6is mechanically fixed to the printed circuit board, and at the same time, is electrically grounded to the printed circuit board.

Referring toFIGS. 4,5,8,9,10, and11, the cap9includes an insertion portion91, a cover portion92, and ribs (reinforcing portion)93. The cap9is integrally formed of a synthetic resin. The cap9is mounted on the receptacle connector3to make it possible to attract the receptacle connector3by an attracting pad of a mounter, not shown, and further also serves to prevent dust, flux liquid or the like from entering the receptacle connector3.

The insertion portion91has a substantially hollow cylindrical shape, and a transverse cross-section thereof has substantially the same shape as that of the shell main body61, and is slightly smaller than the transverse cross-section of the shell main body61. The insertion portion91is inserted in the shell main body61. The insertion portion91has a rear surface (seeFIG. 10) formed with two grooves91a. The grooves91aextend in an inserting/removing direction D2(seeFIG. 10). When the insertion portion91is inserted in the shell main body61, the grooves91arelatively receive the front end portions611aof the locking spring pieces611, to thereby weaken contact pressure of the front end portions611ato the insertion portion91. The insertion portion91has a front surface (seeFIG. 8) formed with two grooves91b. The grooves91bextend in the inserting/removing direction D2(seeFIG. 8). When the insertion portion91is inserted into the shell main body61, the grooves91brelatively receive the front end portions612aof the contact spring pieces612, to thereby weaken contact pressure of the front end portions612ato the insertion portion91.

The cover portion92is substantially plate-shaped, and is continuous with an upper end of the insertion portion91. When the insertion portion91is inserted in the shell main body61, the cover portion92covers an opening of the shell main body61.

As shown inFIGS. 4 and 5, each of the ribs93is substantially plate-shaped, and extends from a portion of the insertion portion91on a front side (left side as viewed inFIG. 5, lower side as viewed inFIG. 4) to a portion of the same on a rear side (right side as viewed inFIG. 5, upper side as viewed inFIG. 4). Each rib93is continuous with the insertion portion91and the cover portion92. A portion of each rib93toward the housing (lower portion as viewed inFIG. 5) has a recess for avoiding interference of the contact arranging portion42. The ribs93are on an inner peripheral surface of the insertion portion91at locations corresponding respectively to the grooves91aof the insertion portion91. That is, the ribs93are each located at the back of the associated one of the grooves91aof the insertion portion91, which are pushed by the front end portions611aof the locking spring pieces61, respectively, when the insertion portion91is inserted into the shell main body61.

Next, a description will be given of an operation for mounting the connector unit1on the printed circuit board.

First, the cover portion92of the cap9mounted on the receptacle connector3is attracted by the attracting pad of the mounter, and the receptacle connector3is disposed at a predetermined location on the printed circuit board. At this time, the through hole terminals62of the shell6are inserted in the through holes in the printed circuit board, and the terminal portions52of the contacts5and5′ are disposed on the pad of the printed circuit board.

Next, the printed circuit board is conveyed to the reflow furnace, and the temperature of the inside of the reflow furnace is raised to a predetermined temperature to solder the receptacle connector3to the printed circuit board. At this time, the cap9is softened by heat, causing the portions of the insertion portion91pressed by the locking spring pieces611are about to be dented. However, the pressed portions are in a state reinforced by the ribs93, and hence deformation of the cap9is suppressed. Further, the contact pressure of the locking spring pieces611becomes small due to the grooves91a, and hence the deformation of the cap9is further suppressed.

Through the above-mentioned processing flow, electronic components including the receptacle connector3are mounted on one surface of the printed circuit board. If electronic components are also mounted on the other surface of the printed circuit board, it is necessary to invert the printed circuit board upside down. Since the cap9is hardly deformed, even if the printed circuit board is inverted upside down, the cap9does not come off the receptacle connector3. Therefore, it is possible to prevent the cap9from falling off.

According to the present embodiment, the ribs93are formed on the inner peripheral surface of the insertion portion91at the locations corresponding respectively to the grooves91ain the outer peripheral surface of the insertion portion91, with which the locking spring pieces611are engaged. This causes the ribs93to receive the returning force of the locking spring pieces611. As a consequence, the deformation of the cap9due to heating during a reflow soldering operation is positively suppressed. Therefore, when the printed circuit board on which the connector unit1is mounted is inverted upside down, or when the printed circuit board on which the connector unit1is mounted is conveyed, it is possible to prevent the cap9from falling off.

Further, the shell main body61of the shell6has the locking spring pieces611which are engaged with the grooves91aof the insertion portion91of the cap9, and hence the urging force of the locking spring pieces611acts on the outer peripheral surface of the insertion portion91, whereby the cap9is positively held by the receptacle connector3.

Further, once the cap9is mounted on the receptacle connector3, it is possible not only to attract the receptacle connector3by the mounter but also to prevent liquid or dust from entering the receptacle connector3during the operation of mounting the connector unit1or during the conveying of the printed circuit board on which the connector unit1is mounted.

In the present embodiment, the ribs93as the reinforcing portion are formed on the inner peripheral surface of the insertion portion91at the locations corresponding respectively to the positions on the outer peripheral surface of the insertion portion91, with which the locking spring pieces611are engaged. However, even if the locking spring piece611is located between the two ribs93in an arranging direction of the grooves42, it is possible to suppress deformation of the cap9, and hence it is not necessarily required to provide the reinforcing portions at the above-mentioned locations.

Further, although the connector unit1according to the present embodiment includes the locking spring pieces611, the connector unit1may not have the locking spring pieces.

Although in the present embodiment, the two plate-shaped ribs93are employed as the reinforcing portion, the reinforcing portion is not limited to the two plate-shaped ribs93, but may be prism-shaped or block-shaped reinforcing portion(s). That is, the shape of the reinforcing portion(s) is not limited to a plate-like shape, and the number of reinforcing portions is not limited, but may be one, or three or more.

Further, although in the present embodiment, the locking spring pieces611and the contact spring pieces612are formed at respective locations displaced from each other (locations displaced in the arranging direction of the grooves42), the locking spring pieces611and the contact spring pieces612may be disposed in a manner opposed to each other via the insertion portion91in a manner sandwiching the ribs93as the reinforcing portion. Further, the shape and the number of the spring pieces are not limited to those of the spring pieces in the present embodiment.

It is further understood by those skilled in the art that the foregoing are the preferred embodiments of the present invention, and that various changes and modification may be made thereto without departing from the spirit and scope thereof.