WO2012042332A1

WO2012042332A1 - Receptacle

Info

Publication number: WO2012042332A1
Application number: PCT/IB2011/002217
Authority: WO
Inventors: Hideaki Ujihara; Syunji Nishigaki; Hirohisa Okuno; Yoko Fujiwara
Original assignee: Panasonic Corporation
Priority date: 2010-09-27
Filing date: 2011-09-23
Publication date: 2012-04-05
Also published as: JP2012074163A; JP5584572B2

Abstract

A receptacle includes a body including contactor catchers for making contact and electrical connection with contactors; a cover attached to a front side of the body and provided with insertion holes for reception of the contactors; and a door member slidable between an opening position in which the door member opens the insertion holes and a closing position in which the door member closes the insertion holes. The body includes a rail along which the door member is slid in a specified sliding direction, a return spring for biasing the door member toward the closing position and holder portions for keeping the door member slidably held in the body.

Description

RECEPTACLE

Field of the Invention The present invention relates to a receptacle.

Background of the Invention

There are conventionally known receptacles that include contactor catchers for making contact and electrical connection with contactors such as plug pins or conductor pins. One example of such receptacles is disclosed in Japanese Patent Application Publication No. 2005-032596. The conventional receptacle disclosed in Japanese Patent Application Publication No. 2005-032596 is provided with a receptacle casing including a generally box-shaped body formed to have such a size that it can be attached to a standardized embedment box and a cover formed in a size greater than the size of the body and combined with the body at the open surface side. On the front surface of the cover, there are formed receptacle holes composed of a pair of contactor insertion holes for the reception of plural kinds of contactors such as plug pins and conductor pins and three-electrode-type receptacle holes composed of three plug pin insertion holes for the reception of flat plug pins including a grounding-electrode plug pin. Arranged within the receptacle casing are contactor catchers and plug pin catchers for making contact and electrical connection with the contactors and the plug pins inserted into the contactor insertion holes and the plug pin insertion holes. The conventional receptacle is further provided with a first door (door member) for openably closing the contactor insertion holes and a second door (door member) for openably closing the plug pin insertion holes that make up the three- electrode-type receptacle holes. The conventional receptacle is additionally provided with a middle frame arranged between the body and the cover to slidably support the first and second door members stored inside the cover.

In the conventional receptacle referred to above, the respective door members are just placed on the middle frame in the assembling process of the receptacle until they are gripped between the middle frame and the cover. There is no way to hold the respective door members in place. For this reason, it is necessary to perform an assembling work while caution is taken not to drop the door members from the middle frame in the assembling process. This makes it difficult to perform the assembling work with ease.

Summary of the Invention In view of the above, the present invention provides a receptacle capable of making it easy to perform an assembling work with no need to pay attention to a door member .

In accordance with the present invention, there is provided a receptacle includes a body including contactor catchers for making contact and electrical connection with contactors; a cover attached to a front side of the body and provided with insertion holes for reception of the contactors; and a door member slidable between an opening position in which the door member opens the insertion holes and a closing position in which the door member closes the insertion holes. The body includes a rail along which the door member is slid in a specified sliding direction, a return spring for biasing the door member toward the closing position and holder portions for keeping the door member slidably held in the body.

The holder portions may be arranged to interpose the rail therebetween and are formed to extend along the sliding direction.

Preferably, the contactor catchers may be arranged in the body to interpose the rail therebetween, each of the holder portions including a restraint rib for, when the door member is tilted to one side about the rail, coming into engagement with a lifted portion of the door member to restrain sliding movement of the door member.

Each of the holder portions may include a groove portion into which one end portion of the door member is fitted and a locator rib for locating the door member in the sliding direction when the door member is forcibly pushed into each holder portion and fitted into the groove portion.

Further, each of the holder portions may include a groove portion into which one end portion of the door member is fitted and a taper portion formed to make contact with the door member and inclined in such a direction as to guide the door member into the groove portion when the door member is forcibly pushed into each holder portion and fitted into the groove portion.

Each of the holder portions may include a groove portion into which one end portion of the door member is fitted, the door member including a taper portion formed to make contact with each holder portion and inclined in such a direction as to guide the door member into the groove portion when the door member is forcibly pushed into the holder portion and fitted into the groove portion.

According to the present invention, the holder portions can hold the door member in the body, thereby preventing the door member from dropping from the body. Accordingly, an assembling work can be easily carried out with no need to pay attention to the door member in the assembling process. Brief Description of the Drawings The objects and features of the present invention will become apparent from the following description of embodiments, given in conjunction with the accompanying drawings, in which:

Fig. 1 is an exploded perspective view showing a receptacle according to one embodiment of the present invention;

Figs. 2A and 2B are perspective and section views showing an upper body and a lower body of the receptacle combined together;

Figs. 3A through 3C are plan, bottom and side views for explaining a door member employed in the receptacle;

Fig. 4A is a partially exploded perspective view showing a voltage-electrode contactor catcher and a voltage- electrode terminal plate, and Fig. 4B is a partially exploded perspective view showing a grounding-electrode contactor catcher and a grounding-electrode terminal plate;

Figs. 5A and 5B are plan and section views for explaining how to keep the door member held in the upper body;

Figs . 6A through 6C are views for explaining how window holes are closed by the door member, Fig. 6A being a plan view illustrating a normal state, Fig. 6B being a plan view illustrating a state in which the contactors of a plug are inserted into first insertion holes and Fig. 6C being a plan view in which the contactors of a plug are inserted into second insertion holes;

Figs . 7A and 7B are views for explaining holder portions employed in the receptacle, Fig. 7A being a perspective view of the receptacle with a cover removed for clarity and Fig. 7B being an enlarged view of the area surrounded by a broken line in Fig. 7A;

Figs. 8A through 8C are views for explaining how to prevent insertion of only one of the contactors, Fig. 8A being a rear view illustrating the door member and a portion of the upper body, Fig. 8B being an enlarged view of the door member and the upper body shown in Fig. 8A, and Fig. 8C being a rear section view illustrating a portion of the door member and a portion of the upper body;

Fig. 9A is a bottom view of the cover of the receptacle and Fig. 9B being a bottom view of a cover provided with ribs;

Figs. 10A and 10B are front and side views showing the receptacle in an assembled state;

Fig. 11 is a front view illustrating the receptacle attached to a fixing frame and a decoration plate; and

Fig. 12 is an exploded perspective view of the receptacle provided with pillar terminals.

Detailed Description of the Preferred Embodiments

A receptacle according to one embodiment of the present invention will now be described with reference to the accompanying drawings which form a part hereof .. In the following description, the up-down direction and the left- right direction will be defined on the basis of Fig. 1. The direction orthogonal to the up-down direction and the left- right direction is referred to as front-rear direction. The upper side in the following description denotes the front side in the claims.

Referring to Fig. 1, the receptacle of the present embodiment includes an upper body 4 and a lower body 2 for holding a pair of voltage-electrode contactor catchers 6 and a grounding-electrode contactor catcher 7. Contactors (not shown) of a plug (not shown) can make contact and electrical connection with the voltage-electrode contactor catchers 6 and the grounding-electrode contactor catcher 7. The receptacle of the present embodiment further includes a cover 3 attached to the upper surface of the upper body 4 and provided with insertion holes 30, 31 and 32 for reception of the contactors and a door member 5 slidable between an opening position where the door member 5 opens the insertion holes 30, 31 and 32 and a closing position where the door member 5 closes the insertion holes 30, 31 and 32. When combined together, the upper body 4, the cover 3 and the lower body 2 make up a housing 1.

The lower body 2 is made of, e.g., a thermosetting resin such as a urea resin. As can be seen in Fig. 1, a generally T-like partition wall 20 is formed within the lower body 2. Three storage compartments 21 in total, including two front storage compartments and one rear storage compartment, are defined within the lower body 2 by the partition wall 20. Voltage-electrode terminal plates 8 to which the voltage-electrode contactor catchers 6 are fixed by caulking are stored within the two front storage compartments 21. Grounding-electrode terminal plates 9 to which the grounding-electrode contactor catcher 7 is fixed by caulking are stored within the rear storage compartment 21. As shown in Fig. 2B, a pair of circular wire insertion holes 21A for introducing electric wires (not shown) into the lower body 2 therethrough is formed on the lower surface of each storage compartment 21. Two pairs of engagement lugs 22 (only the right pair shown in Fig. 1) protruding outwards and engaging with engagement recesses 44A of the upper body 4 to be set forth later are integrally formed on the left and right surfaces of the lower body 2, respectively.

The cover 3 is made of, e.g., a thermosetting resin such as a urea resin. As can be seen in Fig. 1, the cover 3 has a pair of first insertion holes 30, a pair of second insertion holes 31 and a third insertion hole 32, all of which are formed on the upper surface of the cover 3. Voltage-electrode contactors of a plug can be inserted into the first insertion holes 30 and the second insertion holes 31. A grounding-electrode contactor of a plug can be inserted into the third insertion hole 32. Each first insertion holes 30 is formed of a so-called universal type receptacle hole obtained by combining a rectangular hole for reception of a flat contactor (plug pin) and a circular hole for reception of a round bar type contactor. Each of the second insertion hole 31 and the third insertion hole 32 are formed of a circular hole for reception of a round bar type contactor. The first insertion holes 30 and the third insertion hole 32 serve as three-electrode receptacle holes to which a three-electrode plug is connected. The second insertion holes 31 serve as two-electrode receptacle holes to which a two-electrode plug is connected. Accordingly, different kinds of plugs can be connected to the receptacle of the present embodiment.

The upper body 4 is made of, e.g., a thermosetting resin such as a urea resin. As can be seen in Fig. 1, the upper body 4 is formed into a rectangular parallelepiped shape with an open lower surface . The upper body 4 has a pair of first window holes 40 and a pair of second window holes 41 formed in alignment with the first insertion holes 30 and the second insertion holes 31 of the cover 3, respectively. The first window holes 40 and the second window holes 41 allow the voltage-electrode contactor catchers 6 to be exposed to the outside through the first insertion holes 30 and the second insertion holes 31, respectively. The upper body 4 further has a third window hole 42 formed in alignment with the third insertion hole 32 of the cover 3. The third window hole 42 allows the grounding-electrode contactor catcher 7 to be exposed to the outside through the third insertion hole 32. The window holes 40, 41 and 42 are formed in a substantially equal size to that of the insertion holes 30, 31 and 32, respectively.

As shown in Fig. 1, an upwardly-protruding rail 43 extending in the front-rear direction is formed in the front area of the upper surface of the upper body 4 between the first window holes 40 and between the second window holes 41. The rail 43 is fitted into a guide groove 52A of the door member 5 to be described later, whereby the door member 5 is held in place so that it can move in the front-rear direction. A first storage recess 44 is formed in the middle portion of the rail 43 so that the rail 43 is divided into a front section and a rear section. The lower portion of a return spring 55 is stored in the first storage recess 44 so that the front end portion of the return spring 55 can be supported by the rear end of the front section of the rail 43 and the rear end portion of the return spring 55 can be supported by the front end of the rear section of the rail 43 (see Fig. 2A) .

Referring again to Fig. 1, holder portions 45 for slidably holding the door member 5 are provided on the upper surface of the upper body 4 at the left and right side of the first window holes 40, the second window holes 41 and the rail 43. Each of the holder portions 45 includes a rectangular base piece 45A extending in the front-rear direction and protruding upwards and an side piece 45B protruding inwards from the upper end portion of the base piece 45A. The base piece 45A and the side piece 45B are integrally formed with each other. The base piece 45A, the side piece 45B and the upper surface of the upper body 4 cooperate to define a groove portion 45C into which the left or right end portion of the door member 5 is fitted.

An upwardly-protruding locator rib 45D is integrally formed in the front area of the upper surface of the side piece 45B (see Fig. 2A) . A taper portion 45E inclined inwards and downwards is formed on the upper surface of the side piece 45B at the rear side of the locator rib 45D (see Fig. 7B) . Downwardly-protruding restraint ribs 45F are integrally formed in the front and rear end areas of the lower surface of the side piece 45B (see Fig. 2B and 7B) .

Two pairs of locking pieces 46 (only the front pair shown in Fig. 1) are formed on the front and rear surfaces of the upper body 4. The receptacle of the present embodiment can be attached to a fixing frame (not shown) by bringing the locking pieces 46 into engagement with the fixing frame. Downwardly-protruding rectangular engagement pieces 47 (only the right one shown in Fig. 1) are integrally formed on the left and right surfaces of the upper body 4. Each engagement piece 47 has a pair of rectangular engagement holes 47A. The upper body 4 and the lower body 2 are combined together by bringing the engagement lugs 22 of the lower body 2 into engagement with the engagement holes 47A of the upper body 4. The receptacle of the present embodiment in an assembled state is shown in Figs. 10A and 10B. Fig. 11 shows the receptacle of the present embodiment attached to the fixing frame with a decoration plate 10 mounted to the front surface of the fixing frame. In Fig. 11, a switch 11 is attached to the fixing frame together with the receptacle of the present embodiment .

Referring to Fig. 3A, the door member 5 includes a pair of wing pieces 50 and 51 arranged in an opposing relationship with the insertion holes 30 and 31 corresponding to the voltage-electrode and an middle portion 52 positioned between the wing pieces 50 and 51 to interconnect the wing pieces 50 and 51. Slant surfaces 50A and 51A inclined with respect to the insertion direction of the contactors are formed in the front areas of the upper surfaces of the respective wing pieces 50 and 51. If the contactors are pressed against the slant surfaces 50A and 51A, the door member 5 is slid rearwards, thereby opening the first window holes 40. First circular through-holes 53 for reception of the voltage-electrode contactors of a two- electrode plug are formed in the rear areas of the wing pieces 50. Slant surfaces 53A inclined with respect to the insertion direction of the contactors are formed on the upper surfaces of the wing pieces 50 at the front side of the first through-holes 53. If the contactors are pressed against the slant surfaces 53A, the door member 5 is slid frontwards, thereby opening the second window holes 41 of the upper body 4. A second circular through-hole 54 for reception of the grounding-electrode contactor of a three- electrode plug is formed in the rear area of the middle portion 52. A slant surface 54A inclined with respect to the insertion direction of the contactor is formed on the upper surface of the middle portion 52 at the rear side of the second through-hole 54. If the contactor is pressed against the slant surface 54A, the door member 5 is slid rearwards, thereby opening the third window hole 42 of the upper body 4.

As shown in Fig. 3B, a guide groove 52A into which the rail 43 of the upper body 4 is fitted is formed on the rear surface of the middle portion 52 of the door member 5 to extend in the front-rear direction. If the rail 43 is fitted into the guide groove 52A, the door member 5 can slide along the rail 43. A second storage recess 52B having a width greater than the width of the guide groove 52A is formed in the middle portion of the guide groove 52A. The upper portion of the return spring 55 is stored in the second storage recess 52B. If the door member 5 is slid rearwards, the front end portion of the return spring 55 is pressed by the front inner wall of the second storage recess 52B, causing the return spring 55 to be compressed rearwards Thus, the return spring 55 biases the door member 5 frontwards. If the door member 5 is slid frontwards, the rear end portion of the return spring 55 is pressed by the rear inner wall of the second storage recess 52B, causing the return spring 55 to be compressed forwards. Thus, the return spring 55 biases the door member 5 rearwards. This means that, when slid either frontwards or rearwards, the door member 5 can be returned to the original position by the biasing force of the return spring 55.

As shown in Fig. 3A, upwardly-protruding step portions 50B and 51B are integrally formed in the left and right front areas of the upper surface of the door member 5. As illustrated in Figs. 3B and 3C, taper portions 50C and 51C slanting outwards and upwards are formed in the left and right front areas of the lower surface of the door member 5.

Referring to Fig. 4A, the voltage-electrode contactor catcher 6 includes a first contactor catcher 60 for making contact and electrical connection with the voltage-electrode contactor of a two-electrode plug and a second contactor catcher 61 for making contact and electrical connection with the voltage-electrode contactor of a three-electrode plug. The first contactor catcher 60 is made of a resilient metallic material (e.g., brass) and includes a pair of first mutually-opposing spring pieces 60A and a second spring piece 6OB arranged at a right angle with respect to the first spring pieces 60A. The first spring pieces 60A and the second spring piece 60B are integrally formed with each other. The first spring pieces 60A serve to elastically grip a round bar type contactor. The second spring piece 60B serves to elastically grip a flat contactor (plug pin) in cooperation with the first spring pieces 60A. The lower end portions of the respective spring pieces 60A and 60B are integrally interconnected by a connector piece 60C. The connector piece 60C has a square attachment hole 60D for use in attaching the voltage-electrode terminal plate 8 thereto. The second contactor catcher 61 is made of a resilient metallic material (e.g., brass) and includes a pair of mutually-opposing spring pieces 61A and a connector piece 61B for interconnecting the lower end portions of the respective spring pieces 61A. The spring pieces 61A and the connector piece 61B are integrally formed with each other. The connector piece 6IB has a square attachment hole 61C for use in attaching the voltage-electrode terminal plate 8 thereto.

Referring to Fig. 4A, the voltage-electrode terminal plate 8 is made of an electrically conductive material and includes a pair of strip-shaped base pieces 80 and 11 arranged side by side with a specified gap left therebetween and a connector piece 82 interconnecting the middle portions of the base pieces 80 and 81. Downwardly-protruding contact pieces 8OA extend from the left and right areas of the front edge portion of the base piece 80. Downwardly-protruding extension pieces 81A extend from the left and right areas of the rear edge portion of the base piece 81. The connector piece 82 has a generally square caulking hole 82A formed in the central portion thereof. The first contactor catcher 60 and the terminal plate 8 can be combined together by overlapping the caulking hole 82A and the attachment hole 60D of the first contactor catcher 60, inserting a caulking rivet 6A into the caulking hole 82A and the attachment hole 60D and then caulking the caulking rivet 6A. An auxiliary base piece 83 protruding rearwards extends from the transverse center portion of the base piece 81. A generally rectangular caulking hole 83A is formed in the rear end portion of the auxiliary base piece 83. The second contactor catcher 61 and the terminal plate 8 can be combined together by overlapping the caulking hole 83A and the attachment hole 61C of the second contactor catcher 61, inserting a caulking rivet 6A into the caulking hole 83A and the attachment hole 61C and then caulking the caulking rivet 6A.

The grounding-electrode contactor catcher 7 is made of a resilient metallic material (e.g., brass). As shown in Fig. 4B, the grounding-electrode contactor catcher 7 includes a pair of mutually-opposing spring pieces 70 and a connector piece 71 for interconnecting the lower end - - ■ /

portions of the respective spring pieces 70. The spring pieces 70 and the connector piece 71 are integrally formed with each other. The spring pieces 70 serve to elastically grip a round bar type contactor of a three-electrode plug. Generally L-like attachment pieces 72 protruding outwards are integrally formed in the left and right end portions of the connector piece 71. Each of the attachment pieces 72 has a generally square attachment hole 72A (only the right one shown in Fig. 4B) for use in attaching the grounding- electrode terminal plates 9 to the grounding-electrode contactor catcher 7.

As shown in Fig. 4B, each of the grounding-electrode terminal plates 9 is made of an electrically conductive material and includes strip- shaped base pieces 90 and 91 arranged side by side with a specified gap left therebetween and a connector piece 92 interconnecting the transverse end portions of the base pieces 90 and 91. A downwardly- protruding contact piece 90A extends from one transverse end area of the rear edge portion of the base piece 90. A downwardly-protruding extension piece 91A extends from one transverse end area of the front edge portion of the base piece 91. The connector piece 92 has a generally square caulking hole 92A formed in the central portion thereof. The grounding-electrode contactor catcher 7 and the grounding-electrode terminal plates 9 can be combined together by overlapping the caulking holes 92A of the connector pieces 92 of the grounding-electrode terminal plates 9 and the attachment holes 72A of the grounding- electrode contactor catcher 7, inserting caulking rivets 7A into the caulking holes 92A and the attachment holes 72A and then caulking the caulking rivets 7A.

Each terminal plate 8 has cutouts 84 formed at the left and right sides of the connector piece 82 (Fig. 4A) . Likewise, each terminal plate 9 has a cutout 93 formed in one transverse end portion of the connector piece 92 (see Fig. 4B) . Lock springs 23 each formed by bending an elastic metal plate into a generally C-like shape are inserted into the cutouts 84 and 89. The lock springs 23 serve to perform removal prevention of electric wires introduced into the storage compartments 21 through the wire insertion holes 21A of the lower body 2. Each of the lock springs 23 includes a middle piece 23A opposing to each of the contact pieces 80A and 90A across a wire insertion space. Moreover, each of the lock springs 23 includes a lock piece 23B extending obliquely upwards from the lower end of the middle piece 23A The lock piece 23B locks an electric wire as the tip end portion thereof makes contact with the electric wire inserted through the corresponding wire insertion hole 21A. When the electric wire is locked by the lock piece 23B, the electric wire is brought into elastic contact with corresponding one of the contact pieces 80A and 90A under the restoring force of the lock piece 23B. As a result, the electric wire can make contact and electrical connection with the corresponding one of the contact pieces 8OA and 9OA Referring again to Fig. 1, a pair of release levers 24 each for releasing the locking of the corresponding electric wire by the corresponding lock spring 23 are arranged in each storage compartment 21 of the lower body 2. Each release lever 24 is molded from, e.g., a synthetic resin, and includes a rectangular plate-like operation portion 24A and a pair of leg portions 24B extending from the left and right ends of the operation portion 24A in the front-rear direction. As shown in Fig. 1, a pair of support stands 25 for supporting the release levers 24 in such a fashion that the operation portions 24A are exposed to the outside is arranged in the wall portion of each storage compartment 21 facing outwards. Each release lever 24 is stored within the storage compartment 21 so that the corresponding contact pieces 80A and 90A and the corresponding lock spring 23 can be arranged between the leg portions 24B. Bearing stands (not shown) each having a semicircular arc-shaped slide surface are provided within each storage compartment 21. The end portions of the leg portions 24B of the release lever 24 are placed on the bearing stands, whereby each release lever 24 can rotate about the end portions of the leg portions 24B.

In order to remove the electric wire connected to the contactor catcher 6 or 7 , the operation portion 24A of the release levers 24 is pulled upwards by a finger. This causes rotation of the release lever 24, as a result of which the leg portions 24B press the lock piece 23B of the lock springs 23 downwards. Thus, the lock piece 23B remaining in contact with the electric wires is displaced away from the electric wire, eventually making it possible to remove the electric wire.

Next, description will be made on how to keep the door member 5 held in the upper body 4. Referring to Figs . 5A and 5B, one of the left and right end portions of the door member 5 (the left end portion in Fig. 5B) is first brought into contact with the upper surface of the side piece 45B of one of the holder portions 45 and is forcibly pushed inwards from above, whereby one end portion of the door member 5 is fitted into the groove portion 45C of one of the holder portions 45. Thereafter, the other end of the door member 5 is brought into contact with the upper surface of the side piece 45B of the other holder portion 45 and is forcibly pushed inwards from above, whereby the other end portion of the door member 5 is fitted into the groove portion 45C of the other holder portion 45. By fitting the door member 5 into the groove portions 45C of the respective holder portions 45, it becomes possible to keep the door member 5 slidably held in the upper body 4.

When fitting the door member 5 into the groove portions 45C, the door member 5 is forcibly pushed into the groove portions 45C from above while bringing the corner portions of the door member 5 into contact with the locator ribs 45D. The locator ribs 45D serve to locate the door member 5 in the sliding direction of the door member 5. By bringing the corner portions of the door member 5 into contact with the locator ribs 45D, it is possible to adjust the positional relationship between the first storage recess 44 of the upper body 4 and the second storage recess 52B of the door member 5. If the locator rib 45D would be absent, the door member 5 will be caught by the return spring 55 unless the first storage recess 44 and the second storage recess 52B are accurately overlapped with each other. This makes it impossible to keep the door member 5 held in the holder portions 45. In the present embodiment, the first storage recess 44 and the second storage recess 52B can be accurately overlapped with each other by bringing the corner portions of the door member 5 into contact with the locator ribs 45D. This saves the time otherwise required to align the door member 5.

When fitting the door member 5 into the groove portions 45C, the door member 5 is forcibly pushed into the groove portions 45C from above while bringing the taper portions 50C and 51C into contact with the taper portions 45E of the holder portions 45 as shown in Figs. 5A and 5B . The taper portions 45E of the holder portions 45 are inclined in such a direction as to guide the door member 5 into the groove portions 45C. Therefore, when forcibly- pushing the door member 5 into the groove portions 5C, the end portions of the door member 5 are slid along the taper portions 45E and guided into the groove portions 45C. This makes it possible to easily fit the door member 5 into the groove portions 45C. The taper portions 50C and 51C of the door member 5 are inclined in such a direction as to guide the door member 5 into the groove portions 45C. Accordingly, when forcibly pushing the door member 5 into the groove portions 45C, the side pieces 45B of the holder portions 45 are slid on the taper portions 50C and 51C and, therefore, the end portions of the door member 5 are guided into the groove portions 45C. This makes it possible to easily fit the door member 5 into the groove portions 45C.

While the taper portions 45E, 50C and 51C are formed in both the holder portions 45 and the door member 5 in the present embodiment, the same effects as stated above can be obtained even if the taper portions are formed in at least one of the holder portions 45 and the door member 5. It goes without saying that the formation of the taper portions in both the holder portions 45 and the door member 5 is more advantageous than the formation of the taper portions in only one of the holder portions 45 and the door member 5.

Next, description will be given on how to close the respective insertion holes 30, 31 and 32 by the door member 5. If the contactors of a plug are not inserted into the insertion holes 30, 31 and 32, the first window holes 40 and the second window holes 41 for reception of the voltage- electrode contactors are all closed by the door member 5 as illustrated in Fig. 6A. Since the contactor catchers 6 and 7 as current supplying portions are closed by the door member 5, it is possible to, when the receptacle of the present embodiment is not in use, prevent occurrence of an electric shock which may otherwise be caused by the touch with the power supplying portions inside the housing 1.

If the contactors of a three-electrode plug are inserted into the first insertion holes 30 and the third insertion hole 32, the slant surfaces 50A, 51A and 54A of the door member 5 are pressed by the respective contactors and slid rearwards as shown in Fig. 6B. In this case, the first window holes 40 and the third window hole 42 are opened to expose the first contactor catchers 60 and the grounding-electrode contactor catcher 7 to the outside. This enables the contactors of the three-electrode plug to make contact and electrical connection with the first contactor catchers 60 and the grounding-electrode contactor catcher 7. At this time, the second window holes 41 remain closed by the door member 5. Accordingly, it is possible to prevent someone to touch the second contactor catchers 61.

If the contactors of a two-electrode plug are inserted into the second insertion holes 31, the slant surfaces 53A of the door member 5 are pressed by the respective contactors and slid frontwards as shown in Fig. 6C. In this case, the second window holes 41 are opened to expose the second contactor catchers 61 to the outside. This enables the contactors of the two-electrode plug to make contact and electrical connection with the second contactor catchers 61. At this time, the first window holes 40 remain closed by the door member 5. Accordingly, it is possible to prevent someone to touch the first contactor catchers 60. If the contactors of the plug are removed from the insertion holes 30, 31 and 32, the door member 5 is returned to the original position by the biasing force of the return spring 55. Thus, the first window holes 40 and the second window holes 41 for reception of the voltage-electrode contactors are all closed by the door member 5.

The receptacle of the present embodiment includes a unit for restraining the sliding movement of the door member 5 when one attempts to insert one of the contactors into only one of the first insertion holes 30 or only one of the second insertion holes 31. The unit for restraining the sliding movement of the door member 5 is made up of restraint ribs 45F formed in each of the holder portions 45 as shown in Figs. 7A and 7B and step portions 50B and 51B (only the step portion 51B shown in Fig. 7B) formed in the respective wing pieces 50 and 51. Referring to Figs. 8A through 8C, if one attempts to insert one of the contactors into only one of the first insertion holes 30 or only one of the second insertion holes 31, the door member 5 is pressed by one of the contactors and swung about the rail 43. Thus, the door member 5 is tilted to one of the left and right sides (to the left side in Figs. 8A through 8C) . At this time, one of the step portions 50B and 51B (the step portion 51B in Figs. 8A through 8C) formed in the lifted end portion of the door member 5 is positioned between the restraint ribs 45F. Accordingly, if one attempts to cause the door member 5 to slide in the front-rear direction, one of the step portions 50B and 51B is stopped by the restraint ribs 45F. This restrains the sliding movement of the door member 5. As a consequence, it is possible to prevent one of the voltage-electrode contactors of the plug from being inserted into only one of the first insertion holes 30 or only one of the second insertion holes 31.

As described above, the receptacle of the present embodiment is capable of keeping the door member 5 held in the upper body 4 through the use of the holder portions 45. This makes it possible to prevent the door member 5 from being dropped from the upper body 4. Accordingly, an assembling work can be easily carried out with no need to pay attention to the door member 5 in the assembling process In a conventional receptacle in which the holder portions 45 are not provided in the upper body 4, a pair of holder ribs 33 is formed on the lower surface of the cover 3 as shown in Fig. 9B . Movement of the door member 5 in a direction other than the sliding direction is restrained by- gripping the left and right surfaces of the door member 5 with the holder ribs 33. In case where the holder ribs 33 are formed in the cover 3, however, there is no way to hold the door member 5 in an assembling process. Therefore, an assembling work needs to be carefully performed so that the door member 5 should not be dropped in the assembling process. Moreover, if the holder ribs 33 are formed in the cover 3, there is a possibility that, when the cover 3 is seen from above, a sink mark is generated in the process of molding the cover 3. In the receptacle of the present embodiment, the holder portions 45 are formed in the upper body 4. This eliminates the possibility that the door member 5 is dropped in the assembling process. In addition, there is no need to form the holder ribs 33 on the lower surface of the cover 3 as in Fig. 9A. This is advantageous in that no sink mark is generated when the cover 3 is seen from above .

In the receptacle of the present embodiment, the lock springs 23 are arranged in the respective terminal plates 8 and 9 to lock the electric wires. Instead of using the terminal plates 8 and 9, it may be possible to employ pillar terminals 100A for fastening electric wires with screws as illustrated in Fig. 12. In this case, a main body 100 having the pillar terminals 100A may be used in place of the lower body 2. The voltage-electrode contactor catchers 6 and the grounding-electrode contactor catcher 7 may be stored within the main body 100. Moreover, a flat middle frame 101 may be used in place of the upper body 4. The middle frame 101 may be placed to cover the upper open surface of the main body 100. The configuration of the middle frame 101 is essentially the same as the configuration of the upper body 4.

While the invention has been shown and described with respect to the embodiments, it will be understood by those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.

Claims

What is claimed is:

1. A receptacle, comprising:

a body including contactor catchers for making contact and electrical connection with contactors;

a cover attached to a front side of the body and provided with insertion holes for reception of the contactors; and

a door member slidable between an opening position in which the door member opens the insertion holes and a closing position in which the door member closes the insertion holes,

wherein the body includes a rail along which the door member is slid in a specified sliding direction, a return spring for biasing the door member toward the closing position and holder portions for keeping the door member slidably held in the body.

2. The receptacle of claim 1, wherein the holder portions are arranged to interpose the rail therebetween and are formed to extend along the sliding direction.

3. The receptacle of claim 1 or 2, wherein the contactor catchers are arranged in the body to interpose the rail therebetween, each of the holder portions including a restraint rib for, when the door member is tilted to one side about the rail, coming into engagement with a lifted portion of the door member to restrain sliding movement of the door member.

4. The receptacle of any one of claims 1 to 3 , wherein each of the holder portions includes a groove portion into which one end portion of the door member is fitted and a locator rib for locating the door member in the sliding direction when the door member is forcibly pushed into each holder portion and fitted into the groove portion.

5. The receptacle of any one of claims 1 to 3 , wherein each of the holder portions includes a groove portion into which one end portion of the door member is fitted and a taper portion formed to make contact with the door member and inclined in such a direction as to guide the door member into the groove portion when the door member is forcibly pushed into each holder portion and fitted into the groove portion.

6. The receptacle of any one of claims 1 to 3 , wherein each of the holder portions includes a groove portion into which one end portion of the door member is fitted, the door member including a taper portion formed to make contact with each holder portion and inclined in such a direction as to guide the door member into the groove portion when the door member is forcibly pushed into the holder portion and fitted into the groove portion.