WO2010038125A1

WO2010038125A1 - Electric outlet

Info

Publication number: WO2010038125A1
Application number: PCT/IB2009/006937
Authority: WO
Inventors: Noboru Hashimoto; Takashi Kawamoto; Maki Kondou; Toshiyuki Takii; Satoru Ueno
Original assignee: Panasonic Electric Works Co., Ltd.
Priority date: 2008-09-30
Filing date: 2009-09-25
Publication date: 2010-04-08
Also published as: TW201021331A; TWI407651B; WO2010038125A4; CN102165648A; CN102165648B

Abstract

An outlet includes an outlet body for supplying electric power to a plug. The outlet body has an insertion surface in which plug blade insertion slots for inserting the plug blades of the plug including a plug case having a front surface from which plug blades are protruded and a rear surface opposite to the front surface in an insertion direction of the plug blades. The outlet includes a door body provided in the outlet body. The door body is movable between a closed state in which it covers the plug blade insertion slots and an open state in which it is separated from the plug blade insertion slots. And the door body has a holding portion for keeping the plug blades inserted into the plug blade insertion slots when the plug blades of the plug are inserted into the plug blade insertion slots.

Description

ELECTRIC OUTLET

Field of the Invention

The present invention relates to an electric outlet and an outlet device having an outlet body having a plug blade insertion slot for inserting plug blades of a plug and for supplying electric power to the plug.

Background of the Invention

In general, as outlets, outlets having a structure of supplying electric power to a plug while electrically connecting to the plug by cramping plug blades of the plug to a blade rest installed in the outlet are known. In such a structure, because the plug is easily unplugged from an outdoor outlet by an external force, due to unplugging of the plug, an operation of an electrical device is unexpectedly stopped, or due to decrease of a contact area between the plug blades of the plug and the blade rest, contact resistance increases and thus a high heat may occur. Accordingly, in order to suppress a problem that the plug is unplugged from the outlet, an unplugging prevention structure of the plug is suggested. For example, in Japanese Patent Laid-open Publication No. 2001-185289, by rotating the plug by a predetermined angle after connecting

-1-

CQMRKIAAπON COPf , the plug to the outlet, a protrusion provided in the blade rest of the outlet is inserted into a transmitting hole formed in the plug blades of the plug, and thus a structure of preventing the plug from being unplugged from the outlet is proposed.

Further, for example, in Japanese Patent Laid-open Publication No. 2004-63164, an outlet includes a main body, a blade receiving portion for receiving plug blades of a plug introduced to the main body by passing though plug blade insertion slots formed in a front surface of the main body, a terminal plate (terminal) for contacting with an electric wire introduced to the main body by passing through an electric wire insertion hole formed in the main body, and a connection unit for connecting the electric wire and the terminal plate, wherein the blade receiving portion and the connection unit are integrally formed with the terminal plate.

Summary of the Invention

Nowadays, an outlet is used as an outdoor outlet attached to an outer wall of a building such as a house, and an electrical device such as an outdoor lighting device attached to the building, or a cleaner for cleaning the inside of a vehicle is connected to the outlet. Further, recently, the outdoor outlet may be used for charging electrical vehicles . Because the outdoor outlet is frequently used for charging electrical vehicles, the number of times of inserting a plug into the outdoor outlet and extracting a plug from the outdoor outlet increases. However, the outlet in Japanese Patent Laid-open Publication No. 2001-185289 describes an outlet in which the number of times of inserting a plug into the outdoor outlet and extracting a plug from the outdoor outlet is few, for example about 100 times. Specifically, by inserting the plug blades into the outlet, a blade rest is elastically deformed and a protrusion of the blade rest is inserted into a transmitting hole of the plug blade. If elastic deformation of the blade rest is repeated, elasticity of the blade rest is deteriorated and thus the protrusion of the blade rest is not inserted into the transmitting hole of the plug blade. As a result, while repeating to insert the plug into the outlet and to extract the plug from the outlet, a function of preventing the plug from being unplugged from the outlet (hereinafter, an unplugging prevention function) may not be operated. Therefore, the outlet has an inappropriate structure for the above-described use in which the number of times of inserting the plug into the outlet and extracting the plug from the outlet is many and thus improvement of the structure is necessary. Further, in the above-described conventional outlet device, a blade receiving portion and a terminal are always electrically connected. Accordingly, when inserting the plug into the outlet device and extracting the plug from the outlet device, an arc discharge may occur and a spark may occur between the plug blades of the plug and the blade receiving portion.

Therefore, when the conventional outlet device is used at a gasoline stand, or a place using a combustible gas, such as a kitchen within a house, a combustible gas may ignite by a spark due to an arc discharge and thus there is a problem in a safety aspect.

In view of the above, the present invention provides an outlet that can suppress deterioration of an unplugging prevention function when the number of times of inserting the plug into the outlet and extracting the plug from the outlet increases .

In view of the above, the present invention also provides an outlet device that can safely use even at a place using a combustible gas, etc.

Hereinafter, means and operation for achieving the purpose of the present invention will be described.

In accordance with a first aspect of the invention, there is provided an outlet including an outlet body for supplying electric power to a plug, the outlet body having an insertion surface in which plug blade insertion slots for inserting the plug blades of the plug including a plug case having a front surface from which plug blades are protruded and a rear surface opposite to the front surface in an insertion direction of the plug blades, the outlet including: a door body provided in the outlet body, the door body being movable between a closed state in which it covers the plug blade insertion slots and an open state in which it is separated from the plug blade insertion slots, and the door body having a holding portion for keeping the plug blades inserted into the plug blade insertion slots when the plug blades of the plug are inserted into the plug blade insertion slots.

With such configuration, as a holding portion is installed in a door body, a blade rest is not excessively elastically deformed, compared with a structure in which an unplugging prevention device is installed between conventional plug blades and blade rest, as in Japanese Patent Laid-open Publication No. 2001-18528, and thus even if the number of times of inserting the plug blades of a plug into plug blade insertion slots and extracting the plug blades of the plug from the plug blade insertion slots increases, deterioration of elasticity of the blade rest can be suppressed. Therefore, even if the number of times of inserting the plug into the outlet and extracting the plug from the outlet increases, when inserting the plug into the outlet, the plug blades can maintain a state inserted into the plug blade insertion slot. That is, deterioration of an unplugging prevention function can be suppressed. In the outlet, a bias unit for biasing the door body toward the plug blade insertion slots, wherein the bias unit may bias the door body to keep the holding portion in contact with the plug while the plug blades of the plug are inserted into the plug blade insertion slots, and the bias unit may bias the door body to cover the plug blade insertion slots while the plug blades of the plug are not inserted into the plug blade insertion slots.

With such configuration, because the holding portion maintains a contact state with the plug by the bias means, even if the holding portion is trying to be separated from the plug due to an external impact, etc., the holding portion is biased toward the plug by the bias means. Therefore, deterioration of an unplugging prevention function that may be caused when the holding portion is separated from the plug can be suppressed.

Because a closed state of the door body can be maintained by an operation of the bias means, after the door body is opened, it can be avoided to forget to close the door body. Therefore, in a state where the plug is not inserted into the outlet, a case where water, etc. penetrates into the plug blade insertion slot can be reduced. Thereby, according to a structure of the present invention, both suppression of deterioration of an unplugging prevention function caused as the holding portion is separated from the plug and penetration of water, etc. into the plug blade insertion slot can be reduced.

In the outlet, the holding portion may have a contact portion adapted to contact with the rear surface of the plug case . With such configuration, as a contact portion contacts with a rear surface of the plug case, the plug is regulated to move toward the immediate front of an insertion direction, i.e. in a direction in which the plug blades of the plug are unplugged from the plug blade insertion slot. Therefore, deterioration of an unplugging prevention function can be further suppressed.

In the outlet, the door body may have a door main body for covering the entire plug blade insertion slots, and the holding portion has an inclined portion in which a protruding amount thereof from the door main body increases in the insertion direction of the plug and when the plug blades of the plug are being inserted into the plug blade insertion slots, the door body is moved in a direction of being separated from the plug blade insertion slots by the plug contacting with the inclined portion.

With such configuration, as an inclined portion formed in an inclined shape is installed in the holding portion, when the plug and the inclined portion contact, by inserting the plug, the door body moves in a direction of being separated from the plug blade insertion slot. Therefore, it can be suppressed that the inclined portion obstructs the plug from being inserted into the outlet. As a result, when inserting the plug blades of the plug into the plug blade insertion slot, it can be smoothly executed to move an insertion direction of the plug to the holding portion and an operation of inserting the plug into the outlet can be easily performed.

In the outlet, the contact portion may be provided in a substantially ^λL' shape contacting with the plug, the contact portion being extended from the inclined portion in the plug insertion direction.

With such configuration, as the contact portion is formed in an approximately ^ΛL' shape, when a rear surface of the plug case of the plug is moved to a position corresponding to the contact portion, the door body rotates by the bias means and thus the rear surface of the plug case contacts with the contact portion. Therefore, only when the plug is inserted into the outlet by an operation of the bias means, an unplugging prevention function of suppressing the plug blades of the plug from being unplugged from the plug blade insertion slot can be performed. As a result, it can be avoided to forget to perform an operation of preventing the plug from being unplugged from the outlet.

In the outlet, the door body may have a door main body of a substantially flat plate shape for covering the plug blade insertion slots, the holding portion may have an inclined portion in which a protruding amount thereof from the door main body increases in the insertion direction of the plug, and when the plug blades of the plug are inserted into the plug blade insertion slots, the plug blades are kept inserted into the plug blade insertion slots by the inclined portion contacting with the plug.

With such configuration, the inclined portion has a force pressing the plug toward an insertion direction by the bias means. Accordingly, in a state where the inclined portion contacts with plug, the plug is biased toward the inside of the insertion direction. Therefore, deterioration of an unplugging prevention function can be suppressed.

In the outlet, when the plug blades of the plug are inserted into the plug blade insertion slots, the door body may cover at least a part of a side surface of the plug. With such configuration, in a state where the plug blades of the plug are inserted into the plug blade insertion slot, because the door body covers at least a part of a side surface of the plug, penetration of water from a part thereof can be suppressed. Therefore, waterproof performance of the plug and the outlet can be improved.

In the outlet, the insertion surface of the outlet body may have a recess portion depressed in the insertion direction of the plug, the recess portion having a bottom surface in which the plug blade insertion slots are provided and a side surface enclosing the bottom surface, the plug is located adjacent to the side surface when the plug blades of the plug are inserted into the plug blade insertion slots, and the holding portion is received in the recess portion when the door body is in the closed state.

With such configuration, as the plug approaches a side surface of the recess portion, when the plug blades of the plug are inserted into the plug blade insertion slots, it can be suppressed that a user's finger contacts with the plug blade. Therefore, an electric shock accident that may occur when the user's hand contacts with the plug blades can be suppressed. Here, an 'approaching' distance indicates a distance in which the user's finger cannot be inserted into space between a side surface of the recess portion and the plug.

Further, when space for receiving the holding portion is not installed in the outlet body, as the holding portion contacts with the outlet body, when the door body is in a closed state, space is formed between the door body and the outlet body and thus water may penetrate into the space. Further, when space for receiving the holding portion is installed in the outlet body separately from the recess portion, a structure of the outlet body becomes complicated, and a size of the outlet increases. In this connection, in the present invention, because the holding portion is received in the recess portion, it can be suppressed that space forms between the door body and the outlet body. In addition, because the recess portion also performs a function of space for receiving the holding portion, space for receiving a separate holding portion may be omitted in the outlet body, and increase in size of the outlet can be suppressed. In the outlet, an elastic member may be provided in at least one of the door body and the outlet body to surround the plug blade insertion slots, wherein when the door body is in the closed state, the elastic member contacts in a compressed state with a peripheral portion surrounding the plug blade insertion slots in the outlet body.

With such configuration, when the door body is in a closed state, because the elastic member and the outlet body closely contact, the plug blade insertion slot can be well sealed by the door body. Therefore, when the plug is not inserted into the outlet, waterproof performance of the outlet can be improved.

In the outlet, when the door body is in the closed state, the holding portion may block the plug blade insertion slots by contacting with entire peripheral portions around the plug blade insertion slots.

With such configuration, when the door body is in a closed state, as the holding portion contacts with a circumferential edge of the plug blade insertion slot, a claw performs a function as a lid of the plug blade insertion slot. Therefore, when the plug is not inserted into the outlet, waterproof performance of the outlet can be improved .

In accordance with a second aspect of the invention, there is provided an outlet device including: a main body- having at a surface thereof a plug blade insertion holes for inserting plug blades of a plug; a blade receiving portion for contacting with and maintaining the plug blades inserted into the plug blade insertion holes; a terminal for contacting with a power source; a switch arranged in an electric circuit between the blade receiving portion and the terminal; a position detection unit for detecting a position of the plug; and a controller for controlling the switch according to a detection result of the position detection unit, wherein the controller includes: a determination unit for determining, based on the detection result of the position detection unit, whether the plug blades of the plug contact with the blade receiving portion and the plug is positioned within a prescribed range in which a distance between the surface of the main body and the plug is less than a predetermined distance; and a switching control unit for closing the switch when it is determined that the plug is positioned within the prescribed range, and for opening the switch when it is determined that the plug is not positioned within the prescribed range.

With such configuration, when the plug blades of the plug contact with the blade receiving portion and when the plug is positioned within a prescribed range in which a distance between one surface of the main body and the plug is less than a predetermined distance, a current flows between the blade receiving portion and the terminal, and when the plug is positioned outside a prescribed range, a current flow between the blade receiving portion and the terminal is intercepted. Accordingly, when the plug blades of the plug contact with the blade receiving portion, or when the plug blades of the plug are separated from the blade receiving portion, power is not supplied to the blade receiving portion and thus when inserting the plug blades of the plug into the blade receiving portion and when extracting the plug blades of the plug from the blade receiving portion, an arc discharge does not occur between the plug blades and the blade receiving portion. Therefore, when inserting the plug blades of the plug into the blade receiving portion and when extracting the plug blades of the plug from the blade receiving portion, occurrence of an arc discharge can be prevented and thus even at a place using a combustible gas, etc., the outlet device can be safely used. Further, because damage of the blade receiving portion due to an arc discharge can be prevented, a lifetime of the blade receiving portion can be extended.

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 of an outlet according to an embodiment of the present invention;

Fig. 2 is a cross-sectional view illustrating a sectional structure of the outlet taken along a vertical direction in the outlet according to an embodiment of the present invention; Fig. 3A is a perspective view illustrating a perspective structure of a door body in the outlet according to an embodiment of the present invention, Fig. 3B is a front view illustrating a front structure of a door body in the outlet according to an embodiment of the present invention, and Fig. 3C is a side view illustrating a side structure of a door body in the outlet according to an embodiment of the present invention;

Fig. 4 is a perspective view illustrating a perspective structure of the outlet viewed from the downside of a vertical direction in the outlet according to an embodiment of the present invention;

Fig. 5A is a perspective view illustrating a perspective structure of the outlet according to an embodiment of the present invention, and Fig. 5B is a side view illustrating a side structure of the outlet according to an embodiment of the present invention; Fig. 6 is a perspective view illustrating a perspective structure of the outlet viewed from the downside of a vertical direction of the outlet according to an embodiment of the present invention; Figs. 7A and 7B are side views illustrating a side structure of a contact state between a door body and a plug in the outlet according to an embodiment of the present invention;

Fig. 8A is a perspective view illustrating a perspective structure of a state in which a plug is inserted into the outlet according to an embodiment of the present invention, and Fig. 8B is an enlarged view illustrating a relationship between a holding portion of a door body and a rear surface of a plug case in the outlet according to an embodiment of the present invention,-

Fig. 9 is a cross-sectional view illustrating a sectional structure of the outlet taken along a vertical direction in a state where a plug is inserted into the outlet according to an embodiment of the present invention; Fig. 1OA is a perspective view illustrating a perspective structure of a state in which a plug is inserted into an outlet according to a second embodiment of the present invention, and Fig. 1OB is an enlarged view illustrating a relationship between a holding portion of a door body and a rear surface of a plug case according to a second embodiment of the present invention; Fig. HA is a perspective view illustrating a perspective structure of an outlet viewed from the downside of a vertical direction according to a third embodiment of the present invention, and Fig. HB is a cross-sectional view illustrating a sectional structure of an outlet taken along a vertical direction according to a third embodiment of the present invention;

Fig. 12A is a perspective view illustrating a perspective structure of an outlet viewed from the downside of a vertical direction according to another embodiment of the present invention, and Fig. 12B is a cross-sectional view illustrating a sectional structure of an outlet taken along a vertical direction according to another embodiment of the present invention; Fig. 13 is a block diagram of an outlet device according to a first embodiment of the present invention;

Fig. 14 is a front view of an outlet device according to a first embodiment of the present invention;

Fig. 15 is an explanatory diagram illustrating operation of an outlet device according to a first embodiment of the present invention;

Fig. 16 is a block diagram of an outlet device according to a second embodiment of the present invention;

Fig. 17 is a side view of an outlet device according to a second embodiment of the present invention;

Fig. 18 is an explanatory diagram illustrating use of an outlet device according to a second embodiment of the present invention; and

Fig. 19 is a side view of an outlet device according to another embodiment of the present invention.

Detailed Description of the Preferred Embodiments

(First Embodiment)

An outlet according to a first embodiment of the present invention is an outdoor outlet attached to an outer wall of a building such as a house and will be described hereinafter in detail with reference to Figs. 1 to 8B.

As shown in Fig. 1, an outdoor outlet 1 is attached to a wall surface of the outer wall and includes an outlet body 2 having a plug blade insertion slot 21a (see Fig. 2) for inserting plug blades 5a of a plug 5 (see Figs. 7A and 7B), a door body 3 for opening and closing the plug blade insertion slot, and a rotation device 4 installed in the door body 3 and for executing an opening and closing operation of the door body 3.

Hereinafter, a direction perpendicular to the wall surface is referred to as a ^λ front-rear direction', a direction receding from the wall surface is referred to as ^λthe front', and a direction advancing toward the wall surface is referred to as ^λthe rear' . Further, a direction in which the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a is referred to as an λ insertion direction' .

A body 10 to be a base is installed in the outlet body 2. An outlet block 20 having the plug blade insertion slot 21a is attached to the body 10. At the rear of a front-rear direction of the outlet block 20, a waterproof packing 30 is attached to the body 10. At the rear of a front-rear direction of the waterproof packing 30, an attaching body 40 for fixing the outdoor outlet 1 to the wall surface as attached to the wall surface is installed. Further, a cover body 50 is installed at the front of a front-rear direction of the body 10.

A frame body 11 of a frame shape for attaching the waterproof packing 30 is installed in the body 10. At the upside of a vertical direction of the frame body 11, a cover 12 protruding toward the front of the front-rear direction and having a circular arc shape from a side view is installed. A lower end portion 12b of a vertical direction of a side surface of the cover 12 is inclined downward of a vertical direction as advancing toward the rear of the front-rear direction.

An outlet case 21 for forming an outer frame of the outlet block 20 is installed in the outlet block 20. Within the outlet case 21, a blade rest 22 (see Fig. 2) for receiving the plug blades 5a of the plug 5, a lock spring (not shown) for maintaining an electric wire taken out from the wall surface, and a release button (not shown) for releasing the lock spring are received.

In the outlet case 21, a plug blade insertion slot 21a formed in an insertion surface 21g of the plug blades 5a of the plug 5 and an electric wire insertion slot for inserting the electric wire into the lock spring are installed. Further, a body attaching portion 21c attached to the body 10 by a volt is installed in the outlet case 21.

As described above, the waterproof packing 30 is an elastic member attached to the rear of the front-rear direction of the frame body 11. The waterproof packing 30 allows the wall surface and the body 10 to closely contact and thus suppresses penetration of water such as rainwater into the outdoor outlet 1 through space between the waterproof packing 30 and the wall surface. In the waterproof packing 30, a fitting portion 31 of a step shape for fitting to the frame body 11 of the body 10 and a front insertion portion 32, which is a penetration hole for inserting the electric wire taken out from the wall surface toward the outlet block 20 are installed.

An attaching body 40 is received within the waterproof packing 30. In the attaching body 40, an attaching portion 41 to be attached to the wall surface by a volt (not shown) and a rear insertion portion 42 for inserting the electric wire toward the front insertion portion 32 and the outlet block 20 are installed. The door body 3 includes a door main body 60 of a substantially flat plate shape and a holding portion 70 installed in the door main body 60. The door main body 60 is disposed downward of a vertical direction of the cover 12 and opens and closes some of the cover 12 at the downside of a vertical direction thereof.

The rotation device 4 contacts with a lower part of the waterproof packing 30 in a vertical direction thereof. The rotation device 4 includes a shaft 80 serves as a rotation center of the door body 3, a spring member 81 inserted into and for passing through the shaft 80, and a holding member 90 for holding the shaft 80 and the spring member 81. The spring member 81 of the present embodiment uses a torsion spring. Next, an internal structure of the outdoor outlet 1 will be described with reference to Fig. 2.

As shown in Fig. 2, the outlet block 20 is disposed at the front of the front-rear direction further than the frame body 11 of the body 10 and is received within the cover 12. A portion of the outlet block 20 is inserted into an insertion port 12a, which is a penetration hole installed downward of a vertical direction of the cover 12. Specifically, in a state where an engaging portion 21d of a projection shape installed over an entire circumference of a side surface of the outlet case 21 of the outlet block 20 contacts with a circumferential edge of the insertion port 12a, as an insertion portion 21e of the front end side thereof is inserted into the insertion port 12a in the engaging portion 21d of the outlet case 21, the outlet block 20 is disposed at the cover 12. Further, the insertion port 12a has an inclined shape upward of a vertical direction as advancing toward the front of the front-rear direction. Therefore, the outlet block 20 has a shape inclined toward the front of the front-rear direction as advancing downward of a vertical direction and is attached to the cover 12. In the outlet case 21, a plug blade insertion slot 21a is formed in a bottom surface 21fl, which is a surface corresponding to the insertion port 12a. The plug blade insertion slot 21a is inclined upward of a vertical direction as advancing toward the front of the front-rear direction, as in the insertion port 12a.

Further, at the downside of a vertical direction of the insertion port 12a, the rotation device 4 is installed to be adjacent to the insertion port 12a. The door body 3 is attached to the rotation device 4. When the plug 5 (see Figs. 7A and 7B) is not inserted into the plug blade insertion slot 21a, the door body 3 is operated by the rotation device 4 to cover the insertion port 12a (insertion surface 2Ig) from downward of a vertical direction (hereinafter, a form in which the door body 3 covers the insertion port 12a from downward of a vertical direction is referred to as a ^λ closed state' .) . Specifically, when the door body 3 is in a closed state, the door body 3 covers the plug blade insertion slot 21a at a front surface 12A side (i.e. a surface side of the insertion surface 2Ig) of an insertion direction in which the plug 5 in the insertion port 12a (insertion surface 2Ig) is inserted into the outdoor outlet 1.

When the plug 5 is inserted into the plug blade insertion slot 21a, in the closed state, the door body 3 is operated by the rotation device 4 to be separated from the insertion port 12a (the plug blade insertion slot 21a) downward of a vertical direction from the insertion port 12a (insertion surface 2Ig) (hereinafter, a state in which the door body 3 is separated from the insertion port 12a is referred to as an ^λopen state' .) . The frame body 11 of the body 10 contacts with the waterproof packing 30 at the rear of the front-rear direction thereof. An outer size of the waterproof packing 30 is formed to be almost equal to that of the frame body 11. The attaching body 40 contacts with the waterproof packing 30 from the rear of the front-rear direction thereof. An outer size of the attaching body 40 is formed small than that of the waterproof packing 30, and the attaching body 40 is received within a circumferential wall 33 installed at the rear of the front-rear direction of the waterproof packing 30.

A volt insertion portion 11a, which is a penetration hole for inserting a volt for fixing to the wall surface is installed in the frame body 11 of the body 10. In the waterproof packing 30, an insertion portion 34, which is a penetration hole inserted into and for passing through the volt insertion portion 11a is installed at a location corresponding to the volt insertion portion 11a. In the attaching body 40, a volt insertion portion 43, which is a penetration hole communicating with a penetration hole of the volt insertion portion 11a is installed at a location corresponding to each of the volt insertion portion 11a and the insertion portion 34. Thereby, the waterproof packing 30 and the attaching body 40 maintain positions thereof with inserted between the body 10 and the wall surface in the front-rear direction. Further, the cover body 50 is formed to cover the cover 12 from the cover 12 to the downside of a vertical direction. Specifically, a front surface 51 of the front- rear direction of the cover body 50 is formed to extend downward of a vertical direction rather than the front surface 12A of the front-rear direction of the cover 12. A side surface 52 of the cover body 50 is formed to extend downward of a vertical direction as advancing toward the rear of the front-rear direction. More specifically, the cover 12 is formed so that an amount of extending downward of a vertical direction of the side surface 52 increases as advancing toward the rear of the front-rear direction. The side surface 52 is formed to have almost the same size as that of a vertical direction of the frame body 11 while contacting with the frame body 11 of the body 10.

Next, a detailed structure of the door body 3 will be described with reference to Figs. 3A to 3C. In Pigs. 3A to

3C, in a state where the door body 3 is attached to the body

10, a direction perpendicular to the front-rear direction is referred to as a 'length direction'.

As shown in Fig. 3A, in the door main body 60 of the door body 3, a shaft insertion portion 61 of a substantially cylindrical shape for inserting the shaft 80 of the rotation device 4 is installed at the rear of the front-rear direction, and a grasp portion 62 for rotating the door body 3 by a user's hand is installed at the front of the front- rear direction. Further, a circumferential wall 63 protruding toward the insertion port 12a (see Fig. 2), i.e. upward of a vertical direction is installed at a circumferential edge of the door main body 60. The circumferential wall 63 is installed over an entire length of each side at two sides of both side portions of a length direction of the door main body 60 and at one side of the front of the front-rear direction.

As shown in Fig. 3C, the grasp portion 62 is formed to protrude downward of a vertical direction from the door main body 60. Specifically, in the grasp portion 62, a protruded portion 62a protruding downward of a vertical direction as advancing toward the front of the front-rear direction from the door main body 60, and a rib 62b installed at both side portions of a length direction of the protruded portion 62a and for reinforcing the protruded portion 62a are installed. The rib 62b is formed in an entire vertical direction of the protruded portion 62a and has an increasing width in the front-rear direction from the protruded portion 62a as advancing toward the door main body 60 from an end portion of the downside of a vertical direction of the protruded portion 62a.

Further, in the end portion of the downside of a vertical direction of the protruded portion 62a, a projection 62c protruding toward the front of the front-rear direction from the end portion is formed. The projection 62c is formed in an entire length direction of the protruded portion 62a. The user's finger is easily latched by the projection 62c.

As shown in Fig. 3B, the holding portion 70 is integrally formed at the front of the front-rear direction in the door main body 60. The holding portion 70 includes three claws 71 disposed at a predetermined distance in a length direction and a connection portion 72 for connecting the claws 71.

In the claw 71, at the front of the front-rear direction thereof, an inclined portion 71a inclined upward of a vertical direction as advancing toward the rear of the front-rear direction is formed, and at the rear of the front-rear direction thereof, an end portion 71b having a step shape downward of a vertical direction from a top portion of the inclined portion 71a is formed. In the end portion 71b, a first surface 71bl, which is a surface extended downward of a vertical direction from the top portion of the inclined portion 71a and a second surface 71b2, which is a surface extending toward the rear of the front-rear direction from a lower end portion of a vertical direction of the first surface 71bl are formed. Further, the connection portion 72 is connected to end portions of the rear of the front-rear direction of the claw 71 as extending in a length direction.

Next, a state of the door body 3 according to whether the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a is described with reference to Fig. 2 and Figs. 4 to 7B.

First, when the plug blades 5a of the plug 5 are not inserted into the plug blade insertion slot 21a, i.e., when the door body 3 is in a closed state, the door body 3 is described with reference to Fig. 2 and Figs. 4 to 5B .

As shown in Fig. 4, the door main body 60 of the door body 3 covers an entire surface of the plug blade insertion slot 21a from the downside of a vertical direction. That is, the outer side of the door main body 60 has a size greater than the plug blade insertion slot 21a. Specifically, as shown in Fig. 2, in the circumferential wall 63 of the door main body 60, an entire surface of a surface opposite to the insertion port 12a of the cover 12 contacts with a circumferential edge of the insertion port 12a. In this state, the spring member 81 (see Fig. 1) exerts a force for biasing the circumferential wall 63 toward a circumferential edge of the insertion port 12a. Accordingly, for example, as the door body 3 rotates downward of a vertical direction by a self-weight of the door body 3, it is suppressed that space is formed between the circumferential wall 63 and a circumferential edge of the insertion port 12a.

Further, in an insertion surface 21g of the outlet case 21, a recess 2If having a circular plane while being inwardly recessed in an insertion direction of the plug blades 5a of the plug 5, i.e. while being inwardly recessed upward of a vertical direction in Fig. 2 is formed. The recess 21f includes a bottom surface 21fl for forming the plug blade insertion slot 21a and a side surface 21f2 extending to the immediate front (i.e. downward of a vertical direction) of the insertion direction while enclosing a circumferential edge of the bottom surface 21fl. A part of the plug case 5b (see Fig. 7B) of the plug 5 is inserted into the recess 21f.

However, as described above, when the holding portion 70 is installed in the door main body 60 of the door body 3, it is necessary to install a receiving portion of the holding portion 70 at the outlet body 2 side. That is, if a receiving portion of the holding portion 70 is not installed at the outlet body 2 side, the holding portion 70 and the outlet case 21 contact before the circumferential wall 63 and a circumferential edge of the insertion port 12a contact and thus space is formed between the circumferential wall 63 and the insertion port 12a. As a result, waterproof performance of the outdoor outlet 1 may be deteriorated. When installing the receiving portion of the holding portion 70 at the outlet body 2 side, if an exclusive structure for receiving only the holding portion 70 is formed, a shape of the outlet body 2 becomes complex and a size of the outlet body 2 increases .

In this connection, in the present embodiment, the holding portion 70 is received in the recess 21f provided in the outlet case 21. Specifically, as space is formed between the holding portion 70 and the bottom surface 21fl, the holding portion 70 is received in the recess 21f so as to avoid a contact between the holding portion 70 and the bottom surface 2 IfI. Therefore, the circumferential wall 63 and a circumferential edge of the insertion port 12a can maintain a good contact state .

Further, because the recess 2If allows both insertion of a part of the plug case 5b of the plug 5 and reception of the holding portion 70, the outlet body 2 can be formed in a simple shape and it can be suppressed to increase a size of the outlet body 2, compared with a structure having an exclusive portion for receiving only the holding portion 70, as described above.

However, in general, when a door body for covering a plug blade insertion slot is formed to open and close, a user opens the door body in order to insert a plug and may forget to close the door body after extracting the plug. In this case, for example when washing a vehicle near an outdoor outlet, water washing the vehicle may be penetrated into the plug blade insertion slot.

In this connection, in the present embodiment, by installing the spring member 81 in the rotation device 4, the door body 3 is always biased toward the insertion port 12a, and thus it can be avoided that the user forgets to close the door body 3.

Further, as shown in Figs. 5A and 5B, when the door body 3 is in a contact state with the insertion port 12a, the projection 62c and a lower portion of a vertical direction of the protruded portion 62a of the door body 3 protrude downward of a vertical direction from the cover body 50. Accordingly, even when the door body 3 is in a contact state with the insertion port 12a, the user's finger can be latched to the projection 62c and thus the door body 3 can be easily opened. Next, when the plug blades 5a of the plug 5 are being inserted into the plug blade insertion slot 21a, the door body 3 will be described with reference to Figs. 6 to 7B.

As shown in Fig. 6, when inserting the plug blades 5a of the plug 5 into the plug blade insertion slot 21a, in a state where the circumferential wall 63 and a circumferential edge of the insertion port 12a contact, as shown in Figs. 4 to 5B, the door body 3 separates the circumferential wall 63 from the circumferential edge of the insertion port 12a. Specifically, the projection 62c is latched by the user's finger (not shown), and the door body 3 moves downward of a vertical direction. At this time, the door body 3 rotates downward of a vertical direction about the shaft 80. Here, the plug blade insertion slot 21a includes a power terminal insertion slot 21a2 of a substantially rectangular shape for inserting a pair of power terminals 5al (see Figs. 7A and 7B) of the plug blades 5a of the plug 5 and a ground terminal insertion slot 21a3 of a substantially half-circle shape for inserting a ground terminal 5a2 (see Figs. 7A and 7B) of the plug blades 5a of the plug 5. However, in such a rotating door body, a structure of installing a rotation device at a cover side can be considered. In this structure, because a protrusion formed in the door body is disposed at the rear of the front-rear direction, the door body rotates downward of a vertical direction while advancing toward the front from the rear of the front-rear direction. In such an operation of the door body, because a plug should be inserted from the rear of the front-rear direction further than a position of the door body, it is difficult to insert the plug while maintaining a rotation state of the door body. In this connection, in the present embodiment, because the rotation device 4 is installed in the frame body 11 and the projection 62c of the door main body 60 is formed at the front of the front-rear direction, the door body 3 rotates downward of a vertical direction while advancing toward the rear from the front of the front-rear direction. Accordingly, because the plug 5 can be inserted into the plug blade insertion slot 21a from the front of the front- rear direction in the door body 3, the plug 5 can be easily inserted into the plug blade insertion slot 21a. Further, as shown in Fig. 7A, when the door main body 60 and the plug case 5b for forming an external frame of the plug 5 overlap, a finger (specifically, a finger latched to the projection 62c) maintaining a position of the door main body 60 may be removed. In this case, the door main body 60 rotates toward the insertion port 12a (see Fig. 2) by an operation of a restoring force of the spring member 81 (see Fig. 1) . That is, the door main body 60 rotates upward of a vertical direction while advancing toward the front from the rear of the front-rear direction. Particularly, in Fig. 7A, a contact state of the holding portion 70 (or the door main body 60) and the plug case 5b is maintained. Further, in the present embodiment, the plug case 5b of the plug 5 is formed in a substantially cylindrical shape.

In the above state, when inserting the plug 5 toward the inside of an insertion direction, the door main body 60 rotate downward of a vertical direction while advancing toward the rear of the front-rear direction by a protruding amount from the door main body 60 of the inclined portion 71a by the inclined portion 71a of the holding portion 70. As shown in Fig. 7B, when a top surface 71al of the inclined portion 71a and the plug case 5b contact, the door main body 60 does not rotate in a case other than the change in the front-rear direction of the plug case 5b.

Finally, when the plug blades 5a of the plug 5 are completely inserted into the plug blade insertion slot 21a, the door body 3 will be described with reference to Figs . 8A to 9.

The blade rest 22 received in the outlet block 20 is installed to correspond to each of the plug blades 5a of the plug 5. Specifically, the blade rest 22 includes a blade rest of a power source side for inserting each of a pair of power terminals 5al in the plug blades 5a from both sides of the power terminal 5al, and a blade rest of a ground side for inserting the ground terminal 5a2 in the plug blades 5a from both sides of the ground terminal 5a2. Each of the blade rest of a power source side and the blade rest of a ground side is elastically deformed when inserting the power terminal 5al and the ground terminal 5a2. The blade rest of a power source side and the blade rest of a ground side maintain each of the power source terminal 5al and the ground terminal 5a2 by a restoring force due to such elastic deformation.

However, by rotating the plug shown in Japanese Patent Laid-open Publication No. 2001-185289 by a predetermined angle after connecting the plug to the outlet, in a structure of inserting a projection formed in the blade rest of the outlet into a transmitting hole formed in the plug blade of the plug and of preventing the plug from being unplugged from the outlet, an elastic deformation amount of the blade rest increases, and if elastic deformation of the blade rest repeats, elasticity of the blade rest is deteriorated, and thus a projection of the blade rest is no longer inserted into the transmitting hole of the plug blade . As a result, while repeating insertion and extraction of the plug, as an unplugging prevention function of the plug is deteriorated, an unplugging prevention function may not be performed.

In this connection, in the present embodiment, because a structure in which an unplugging prevention device is not installed between the plug and the blade rest, i.e. a structure of opening and closing the entire plug blade insertion slot 21a by a rotation of the door body 3 is provided, elastic deformation of the blade rest 22 by the plug blades 5a of the plug 5 is suppressed and thus deterioration of an unplugging prevention function can be suppressed, as in Japanese Patent Laid-open publication No. 2001-185289. By rotating the plug shown in Japanese Patent Laid- open Publication No. 2001-185289 by a predetermined angle after connecting the plug to the outlet, in a structure of inserting the projection provided in the blade rest of the outlet into the transmitting hole provided in the plug blades of the plug and of extracting the plug from the outlet, a user may forget an operation of rotating the plug by a predetermined angle. As a result, as the plug is unplugged, an operation of an electric device may be unexpectedly stopped, or as a contact area between the plug blades of the plug and the blade rest decreases, contact resistance increases and thus a high heat may occur.

In this connection, in the present embodiment, when the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a by the spring member 81, the plug 5 is automatically fixed by the holding portion 70 and thus a problem that the plug is unplugged can be suppressed.

Specifically, as shown in Fig. 8A, when the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a, an end portion 71b of the holding portion 70 contacts with a front surface 5d (see Fig. 7B) in which the plug blades 5a are installed in the plug case 5b and a rear surface 5c to be a surface of an opposite side in an insertion direction. Accordingly, it is restricted that the plug 5 moves to the immediate front of the insertion direction. More specifically, as shown in Fig. 8B, the rear surface 5c of the plug case 5b contacts with the first surface 71bl of the end portion 71b. Further, in a central claw 71 among three claws, the rear surface 5c of the plug case 5b contacts with the first surface 71bl thereof, and a side surface 5e of the plug case 5b contacts with the second surface 71b2 thereof.

However, at a time point at which the plug blades 5a of the plug 5 and the blade rest of the outlet case 21 contact, electric power is supplied to the plug blades 5a via the blade rest. At that time, if a user's hand contacts with the plug blades 5a, the user may receive an electric shock. Further, when the plug blades 5a are incompletely inserted into the plug blade insertion slot 21a, the plug blades 5a are exposed to the outside, and thus the user's hand may contact with the plug blades 5a.

In this connection, in the present embodiment, the recess 21f is formed in the outlet case 21, and the plug case 5b is inserted into the recess 21f. Therefore, when inserting the plug blades 5a of the plug 5 into the plug blade insertion slot 21a, the plug blades 5a are inserted into the recess 21f and space communicating from the outside of the plug 5 to the plug blades 5a can be formed small by the plug case 5b and a circumferential edge of the recess 21f. As a result, it can be suppressed that the user's finger contacts with the plug blades 5a through such space. Specifically, as shown in Fig. 9, when the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a, the side surface 5e for connecting the front surface 5d and the rear surface 5c of the plug case 5b and the side surface 21f2 of the recess 21f approach. Due to such a structure, it is suppressed that the user's finger contacts with the plug blades 5a through space between the side surface 5e of the plug case 5b and the side surface 21f2 of the recess 21f. Further, even if the plug blades 5a are incompletely inserted into the plug blade insertion slot 21a, the side surface 21f2 of the recess 21f and the side surface 5e of the plug case 5b are partially overlapped and thus the plug blades 5a are suppressed to expose to the outside. Therefore, it is suppressed that the user's finger contacts with the plug blades 5a. Further, when unplugging the plug 5 in which the plug blades 5a are inserted into the plug blade insertion slot 21a, by rotating the door body 3 downward of a vertical direction while advancing toward the rear of the front-rear direction, in a state where the end portion 71b and the rear surface 5c of the plug case 5b are separated, the plug 5 is pulled toward the immediate front of an insertion direction thereof. Accordingly, the end portion 71b and the rear surface 5c of the plug case 5b can be easily separated, and an unplugging operation of the plug 5 can be easily performed. According to an outlet of the present embodiment, the following advantages can be obtained.

(1) According to the present embodiment, when the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a, the holding portion 70 of the door body 3 keeps the plug blades 5a inserted into the plug blade insertion slot 21a. Therefore, compared with a structure in which a unplugging prevention device is installed between a conventional plug blade and blade rest, as in Japanese Patent Laid-open Publication No. 2001-185289, in the present embodiment, because the blade rest is not excessively elastically deformed, even if the number of times of inserting and extracting the plug blades 5a of the plug 5 into and from the plug blade insertion slot 21a increases, deterioration of elasticity of the blade rest 4 can be suppressed. Therefore, the number of times of inserting the plug 5 into the outdoor outlet 1 and extracting the plug 5 from the outdoor outlet 1 increases, a state in which the plug blades 5a are inserted into the plug blade insertion slot 21a can be maintained. Further, because the door body 3 performs an operation of opening and closing the entire plug blade insertion slot 21a, when the plug 5 is not inserted into the outdoor outlet 1, the door body 3 maintains a closed state and thus penetration of water into the plug blade insertion slot 21a can be suppressed. That is, the door body 3 has both a function of maintaining a state in which the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a and a function of suppressing penetration of water into the plug blade insertion slot 21a. Therefore, compared with a structure of forming a holding portion using the door body 3 and another member, the number of components of the outdoor outlet 1 can be reduced and increase in size of the outdoor outlet 1 can be suppressed.

(2) According to an embodiment of the present invention, an end portion 71b, which is a contact portion contacting with the rear surface 5c of the plug case 5b is installed in the holding portion 70. Therefore, the plug 5 is suppressed to move to the immediate front of an insertion direction thereof, i.e. the plug blades 5a of the plug 5 are suppressed to move in a direction to be unplugged from the plug blade insertion slot 21a. Therefore, the plug 5 can be suppressed to be unplugged from the outdoor outlet 1.

Further, because the end portion 71b contacts with the rear surface 5c of the plug case 5b, it is unnecessary to form a portion for allowing to contact with the end portion 71b in the plug case 5b. Therefore, a shape of the plug case 5b can be simply formed. Further, when forming a portion for allowing to contact with the end portion 71b in the plug case 5b, an exclusive shape of the plug case 5b is necessary. That is, it is necessary that the plug 5 is an exclusive part for the outdoor outlet 1. In this connection, in the present embodiment, even if the plug 5 is a general purpose part, the end portion 71b performs a function of preventing from being unplugged the plug 5 from the outdoor outlet 1.

Further, when a portion for allowing to contact with the end portion 71b is formed in the plug case 5b, particularly, when a projection for contacting with the end portion 71b is formed, if a vehicle runs over the plug case 5b or a user steps on the plug case 5b, the projection may be damaged. As a result, a function of preventing from being unplugged the plug 5 from the outdoor outlet 1 cannot be performed. In this connection, in the present embodiment, because the holding portion 70 is installed in the door body 3 , even if a vehicle runs over the plug 5 or a user steps on the plug 5, a function of preventing from being unplugged the plug 5 from the outdoor outlet 1 can be performed.

(3) According to the present embodiment, as advancing toward the rear from the front of the front-rear direction, the inclined portion 71a in which a protruding amount from the door main body 60 increases is formed in the holding portion 70. Therefore, as the inclined portion 71a is formed in an inclined shape, when the door body 3 and the inclined portion 71a contact, the plug 5 is inserted and thus the door body 3 rotates. Therefore, the inclined portion 71a can suppress obstruction of insertion of the plug blades 5a into the plug 5. As a result, when inserting the plug blades 5a of the plug 5 into the plug blade insertion slot 21a, movement of an insertion direction of the plug 5 to the holding portion 70 can be smoothly performed. Therefore, the plug 5 can be easily inserted into the outdoor outlet 1. (4) According to the present embodiment, the spring member 81, which is a bias unit for biasing the door body 3 toward the plug blade insertion slot 21a is installed in the rotation device 4, and the spring member 81 biases the holding portion 70 to maintain a contact state with the plug case 5b. Therefore, in a state where the plug 5 is inserted into the outdoor outlet 1, even if the holding portion 70 is trying to be separated from the plug case 5b due to an external impact, the holding portion 70 is biased toward the plug case 5b by the spring member 81. Therefore, as the holding portion 70 is separated from the plug case 5b, the plug blades 5a of the plug 5 can be suppressed from being unplugged from the plug blade insertion slot 21a.

(5) According to the present embodiment, when the plug blades 5a of the plug 5 are not inserted into the plug blade insertion slot 21a, the door body 3 has a structure in which the spring member 81 biases to maintain a closed state of the plug blade insertion slot 21a. Therefore, because the door body 3 maintains a closed state by an operation of the spring member 81, after the door body 3 is opened, it can be escaped to forget to close the door body 3. Therefore, in a state where the plug 5 is not inserted into the outdoor outlet 1, it can be reduced that water, etc. penetrates into the plug blade insertion slot 21a.

(6) According to the present embodiment, the end portion 71b has an approximately ^λL' shape contacting with the plug 5 while continuing with the inclined portion 71a at the inside of an insertion direction further than the inclined portion 71. Therefore, as the end portion 71b is formed in an substantially 'L' shape, when the rear surface 5c of the plug case 5b of the plug 5 guided by the inclined portion 71 moves to a position corresponding to the end portion 71b, the door body 3 rotates by the spring member 81 and thus the end portion 71b and the rear surface 5c of the plug case 5b contact. Therefore, by inserting the plug 5 into the outdoor outlet 1 by an operation of the spring member 81, the plug blades 5a of the plug 5 can be suppressed from being unplugged from the plug blade insertion slot 21a.

(7) According to the present embodiment, when the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a, the door body 3 covers the downside of a vertical direction of a side surface of the plug case 5b of the plug 5. Therefore, in a state where the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a, penetration of water from downward of a vertical direction of a side surface of the plug case 5b can be suppressed. Therefore, waterproof performance of the plug 5 and the outdoor outlet 1 can be improved.

(8) According to the present embodiment, the door body 3 rotates downward of a vertical direction as advancing toward the rear from the front of the front-rear direction about the shaft 80. Therefore, the plug 5 is inserted into the outdoor outlet 1 from the front of the front-rear direction of the door body 3. Therefore, the door body 3 can easily insert the plug 5 into the outdoor outlet 1 while maintaining an open state . (9) According to the present embodiment, when the plug blades 5a of the plug 5 are inserted into the plug blade insertion slot 21a, the plug 5 approaches the side surface 2If2 of the recess 2If. Therefore, when inserting the plug blades 5a of the plug 5 into the plug blade insertion slot 21a, it is suppressed that a user's finger contacts with the plug blades 5a. Therefore, an electric shock accident that may occur when the user's finger contacts with the plug blades 5a can be suppressed.

Further, because the gap between the plug case 5b and the side surface 21f2 of the recess 21f is small, when inserting the plug blades 5a of the plug 5 into the plug blade insertion slot 21a, even if the plug 5 is trying to be inclined, the plug case 5b and the recess 21f contact and thus a posture of the plug 5 is maintained. Therefore, an operation of inserting the plug 5 into the outdoor outlet 1 can be easily performed.

In addition, in a state where the plug 5 is inserted into the outdoor outlet 1, even if the plug 5 is trying to be inclined due to an external impact, the plug case 5b contacts with the side surface 21f2 of the recess 21f and thus a posture of the plug 5 is maintained. Therefore, as the plug case 5b is inclined, the end portion 71b and the plug case 5b can be suppressed from being separated from each other, i.e. a function of an unplugging prevention device can be suppressed from being deteriorated. (10) According to the present embodiment, when the door body 3 is in a closed state, the holding portion 70 is received in the recess 21f . Therefore, it can be suppressed to form space between the door body 3 and a circumferential edge of the insertion port 12a of the outlet body 2. In addition, because the recess 21f further performs a function as space for receiving the holding portion 70, it is unnecessary to install separate space for receiving the holding portion 70 in the outlet body 2 and increase in size of the outdoor outlet 1 can be suppressed. (11) According to the present embodiment, the protruded portion 62a is formed in the door main body 60. Therefore, by latching a user's finger to the protruded portion 62a, the door body 3 can rotate.

Further, when the door body 3 is in a closed state, the projection 62c has a structure of protruding downward of a vertical direction from the cover body 50. Therefore, even when the door body 3 is in a closed state, because the projection 62c can be easily latched by a finger, the door body 3 can easily rotate.

(12) According to the present embodiment, the cover body 50 has a structure of covering a circumferential edge thereof so as to enclose the plug blade insertion slot 21a and of extending a lower end portion of a vertical direction of the cover body 50 from the plug blade insertion slot 21a to the downside of a vertical direction. Therefore, because water from the upside of a vertical direction in the outdoor outlet 1 due to rainwater, etc. falls downward of a vertical direction of the outdoor outlet 1 along a surface of the cover body 50, water can be suppressed from penetrating into the plug blade insertion slot 21a. (13) According to the present embodiment, the circumferential wall 63 is installed in the door main body 60, and in a state where the door body 3 is closed, the circumferential wall 63 contacts with a circumferential edge of the insertion port 12a. Therefore, compared with a structure of contacting with one surface of the door main body 60, the door body 3 can more surely contact with a circumferential edge of the insertion port 12a. As a result, in a state where the plug 5 is not inserted into the outdoor outlet 1, waterproof performance of the outdoor outlet 1 can be improved . (Second Embodiment)

An outlet according to a second embodiment of the present invention is an outdoor outlet attached to an outer wall of a building such as a house and will be described hereinafter in detail with reference to Figs. 1OA and 1OB. In the present embodiment, because only a shape of the holding portion of the door body 3 is different, compared with the first embodiment, like reference numerals designate like elements and therefore a detailed description thereof will be omitted. As shown in Fig. 1OA, a holding portion 91 installed in a door main body 60 of a door body 3 in an outdoor outlet IA is integrally formed at a front position of the front- rear direction in the door main body 60, as in the first embodiment. The holding portion 91 includes three claws 92 disposed at a predetermined distance in a length direction and a connection portion (not shown) for connecting the claws 92. Further, an arrangement of three claws 92 is the same as that of the first embodiment.

In the claw 92, a front inclined portion 93 having a shape in which a protruding amount from the door main body 60 as advancing toward the rear from the front of the front- rear direction increases and a rear inclined portion 94 connected to the front inclined portion 93 and having a shape in which a protruding amount from the door main body 60 as advancing toward the rear from the front of the front- rear direction decreases are installed. When the plug 5 is inserted into the outdoor outlet IA, the front inclined portion 93 performs a function of guiding the plug 5. When the plug 5 is inserted into the outdoor outlet IA, the rear inclined portion 94 performs a function of suppressing from being unplugged the plug 5 from the outdoor outlet IA.

Specifically, when inserting the plug 5 into the outdoor outlet IA, the plug case 5b of the plug 5 contacts with the front inclined portion 93. In this state, when moving the plug 5 toward the inside of an insertion direction, the door main body 60 rotates downward of a vertical direction and thus the front inclined portion 93 moves downward of a vertical direction. As shown in Fig. 1OB, when the plug 5 is inserted into the outdoor outlet IA, a connection portion 5f of the rear surface 5c and the side surface 5e of the plug case 5b and the rear inclined portion 94 contact. The rear inclined portion 94 exerts a component of force of moving the plug 5 in a direction toward the inside of an insertion direction by an operation of the spring member 81. Accordingly, the plug 5 is suppressed from being unplugged from the outdoor outlet IA.

However, due to a manufacturing error of the plug case 5b, an assembling error of the plug 5, and an assembling error of the body 10 and the outlet block 20 of the outdoor outlet IA, unbalance may occur at a distance from a bottom surface 21fl of the recess 21f of the outlet case 21 to the rear surface 5c of the plug case 5b (connection portion 5f ) . In this connection, in the present embodiment, because the connection portion 5f contacts with the rear inclined portion 94, a rotation degree of the door body 3 is adjusted, thereby absorbing the unbalance. Specifically, when such a distance is short, the door body 3 rotates upward of a vertical direction and thus a contact between the connection portion 5f and the rear inclined portion 94 is maintained. When such a distance is long, the door body 3 rotates downward of a vertical direction and thus a contact between the connection portion 5f and the rear inclined portion 94 is maintained.

According to the outdoor outlet IA of the present embodiment, in addition to advantages (1) to (13) of the first embodiment, the following advantage can be obtained. (14) According to the present embodiment, when the plug 5 is inserted into the outdoor outlet IA, the rear inclined portion 94 contacts with the connection portion 5f of the plug case 5b. Therefore, even if unbalance occurs at a distance from the bottom surface 21fl of the recess 21f of the outlet case 21 to the rear surface 5c (connection portion 5f) of the plug case 5b, a contact between the rear inclined portion 94 and the connection portion 5f can be maintained. As a result, even if the unbalance occurs, deterioration in performance of an unplugging prevention device can be suppressed. (Third Embodiment)

An outlet according to a third embodiment of the present invention is an outdoor outlet attached to an outer wall of a building such as a house and will be described hereinafter in detail with reference to Figs. HA and HB. In the present embodiment, because only a shape of the holding portion of a door body 3 is different, compared with the first embodiment, like reference numerals designate like elements and therefore a detailed description thereof will be omitted. As shown in Fig. HA, a holding portion 95 of an outdoor outlet IB is integrally formed at the front of the front-rear direction of a door main body 60. The holding portion 95 includes two claws 96 arranged in a length direction and a connection portion for connecting the claws 96. Here, a shape of the claw 96 is almost the same as that of the first embodiment from a side view and therefore a detailed description thereof will be omitted. Further, a width Hl of a length direction of the claw 96 is formed greater than a width of a length direction of the claw 71 of the first embodiment.

When the door body 3 is in a closed state, a top surface 97 of a frame shape installed in each claw 96 contacts with a circumferential edge of each power terminal insertion slot 21a2. That is, the top surface 97 contacts with a circumferential edge of the power terminal insertion slot 21a2 in a form of enclosing the power terminal insertion slot 21a2. Accordingly, even if water penetrates through a gap between the door body 3 and the cover 12 , space between the top surface 97 and the each power terminal insertion slot 21a2 seals and thus penetration of water is suppressed.

As shown in Fig. HB, in a state where the door body 3 is closed, when the claw 96 is inserted into the power terminal insertion slot 21a2, the claw 96 contacts with an opening end 21al of the power terminal insertion slot 21a2 in a length direction. Accordingly, it is suppressed to form space between the power terminal insertion slot 21a2 and the claw 96 in a length direction.

According to the outdoor outlet IB of the present embodiment, in addition to advantages (1) to (13) of the first embodiment, the following advantage can be obtained.

(15) According to the present embodiment, when the door body 3 is in a closed state, the holding portion 95 is inserted into the power terminal insertion slot 21a2. Therefore, the claw 96 of the holding portion 95 performs a function of a lid of the power terminal insertion slot 21a2. Therefore, in a state where the plug 5 is not inserted into the outdoor outlet IB, waterproof performance of the outdoor outlet IB can be improved.

Particularly, in a state where the claw 96 is inserted into the power terminal insertion slot 21a2, the claw 96 and the opening end 2IaI of the power terminal insertion slot 21a2 contact and thus penetration of water into the power terminal insertion slot 21a2 is further suppressed. Therefore, waterproof performance of the outdoor outlet IB can be further improved. Further, in the present embodiment, as in the first and second embodiments, when the door body 3 is in a closed state, a circumferential wall 63 of the door main body 60 and a circumferential edge of the insertion port 12a contact. Therefore, the outdoor outlet IB has both a waterproof function due to a contact between the circumferential wall 63 and a circumferential edge of the insertion port 12a and a waterproof function due to insertion of the claw 96 into the power terminal insertion slot 21a2. As a result, waterproof performance of the outdoor outlet IB can be further improved.

(Modified examples)

The outdoor outlet according to the present embodiment is not limited to the above-described embodiments and can be changed to the following modified examples. Further, the following modified examples are not applied to only the above-described embodiments and the modified examples may be combined together .

In the above embodiments, when the door body 3 is in a closed state, as the circumferential wall 63 of the door main body 60 and a circumferential edge of the insertion port 12a contact with each other, a waterproof structure of suppressing penetration of water into the plug blade insertion slot 21a is formed. However, the waterproof structure of the present invention is not limited thereto. For example, as shown in Fig. 12A, at a position at which the circumferential wall 63 of the door main body 60 is installed, a compressible elastic member 98 such as rubber instead of the circumferential wall 63 may be attached. As shown in Fig. 12B, when the door body 3 is in a closed state, the elastic member 98 is inserted with compressed between the door main body 60 and a circumferential edge of the insertion port 12a. Accordingly, adhesive power between the door main body 60 and the elastic member 98 and between the elastic member 98 and a circumferential edge of the insertion port 12a can be improved. That is, it is suppressed that a gap is formed between the door main body 60 and the elastic member 98 and between the elastic member 98 and a circumferential edge of the insertion port 12a. Therefore, when the door body 3 is in a closed state, waterproof performance of the outdoor outlets 1, IA, and IB can be improved.

Further, the elastic member 98 may be directly attached to the circumferential wall 63. Even in this structure, waterproof performance of the outdoor outlets 1, IA, and IB can be improved.

Further, the elastic member 98 may be directly attached to a circumferential edge of the insertion port 12a. Even in this structure, waterproof performance of the outdoor outlets 1, IA, and IB can be improved. Further, in this case, the same advantage as that of a structure in which the circumferential wall 63 is removed from the door main body 60 can be obtained.

In the above embodiments, the recess 21f is formed in the outlet case 21 of the outlet block 20, however the recess 21f may not be formed in the outlet case 21. Even in this structure, advantages (1) to (8) and (11) to (15) of the embodiments can be obtained.

In the above embodiments, the door body 3 rotates downward of a vertical direction while advancing toward the rear from the front of the front-rear direction about the shaft 80, however the door body 3 may rotate downward of a vertical direction while advancing toward the front from the rear of the front-rear direction. Even in this structure, advantages (1) to (7) and (9) to (15) of the embodiments can be obtained.

In the above embodiments, in a state where the plug 5 is inserted into the outdoor outlets 1, IA, and IB, the door body 3 covers a portion of a lower part of a vertical direction of the plug case 5b of the plug 5, however a structure of the door body 3 is not limited thereto. For example, as two sides of a length direction of the circumferential wall 63 of the door main body 60 extend upward of a vertical direction, in a state in which the plug 5 is inserted into the outdoor outlets 1, IA, and IB, a structure in which the door body 3 covers both side surfaces of the plug case 5b may be formed.

In the above embodiments, the spring member 81 is used as a bias unit, however other means may be used as a bias unit. For example, by attaching a magnet to the door main body 60 and attaching a metal piece of a magnetic material to a circumferential edge of the insertion port 12a corresponding to the magnet, a structure of maintaining a closed state of the door body 3 may be formed.

In the above embodiments, by an operation of the spring member 81, even when the door body 3 is in a closed state, the circumferential wall 63 has a structure of biasing a circumferential edge of the insertion port 12a upward of a vertical direction, however when the door body 3 is in a closed state, the circumferential wall 63 may not bias a circumferential edge of the insertion port 12a. In this case, by installing an engaging portion for engaging with each of the door body 3 and the body 10, a closed state of the door body 3 may be maintained.

In the above embodiments, the inclined portion 71a of a shape in which a protruding amount from the door main body 60 increases as advancing toward the rear from the front of the front-rear direction is formed; however, the shape of the inclined portion of the present invention is not limited thereto. For example, instead of the inclined portion 71a, a curved portion of a curved shape in which a protruding amount from the door main body 60 increases as advancing toward the rear from the front of the front-rear direction may be formed. Further, in the above embodiments, the inclined portion 71a and the front inclined portion 93 are installed in the holding portions 70, 91, and 95; however, the inclined portion 71a and the front inclined portion 93 may be omitted from the holding portions 70, 91, and 95. In the first and third embodiments, as a contact portion, the end portion 71b is installed; however, the shape of the contact portion of the present invention is not limited thereto. For example, as a contact portion, a curved portion curving upward of a vertical direction while advancing toward the front from the rear of the front-rear direction may be formed.

In the third embodiment, the claw 96 is inserted into two power terminal insertion slots 21a2 of the plug blade insertion slot 21a; however, three claws 96 may be installed in and inserted into the ground terminal insertion slot 21a3. In the third embodiment, as in the first and second embodiments, the circumferential wall 63 of the door main body 60 contacts with a circumferential edge of the insertion port 12a, however the circumferential wall 63 may^¬ be omitted from the door main body 60. In this case, although the door main body 60 and a circumferential edge of the insertion port 12a do not contact with each other, waterproof performance of the outdoor outlet IB can be maintained.

In the third embodiment, when the door body 3 is in a closed state, as the claw 96 contacts with a circumferential edge of each power terminal insertion slot 21a2, a waterproof structure of suppressing penetration of water into the each power terminal insertion slot 21a2 is formed; however, the waterproof structure of the present invention is not limited thereto. The each power terminal insertion slot 21a2 and a part of the claw 96 may contact. In this case, it is preferable that a width Hl of the claw 96 is almost the same as a width of the each power terminal insertion slot 21a2. Even in this structure, an advantage similar to an advantage (15) of the third embodiment can be obtained.

In the above embodiments, the plug case 5b of the plug 5 is formed in a substantially cylindrical shape; however, the shape of the plug case 5b is not limited thereto. For example, the plug case 5b may be formed in a rectangular parallelepiped shape. In the above embodiments, the holding portions 70, 91, and 95 are integrally formed with the door main body 60, i.e. the door main body 60 and the holding portions 70, 91, and 95 are formed in a single member; however, the door main body 60 and the holding portions 70, 91, and 95 may be formed as a separate member.

In the above embodiments, the end portion 71b and the rear inclined portion 94 maintain a state applied to the plug case 5b of the plug 5 by an operation of the spring member 81 and have an unplugging prevention function; however, the unplugging prevention function of the present invention is not limited thereto. A structure of maintaining a state where the holding portions 70, 91, and 95 are applied to the plug case 5b and having an unplugging prevention function may be used. Therefore, for example, an engaging claw may be installed in the holding portion and may be provided to engage with the plug case 5b.

In the above embodiments, the outlet can be applied to the outdoor outlets 1, IA, and IB; however, the outlet of the present invention is not limited thereto. For example, the outlet of the present invention can be applied to an indoor outlet.

(Fourth embodiment)

An outlet device (hereinafter, referred to as an 'outlet') P of the present embodiment is an indoor outlet using for supplying power from a power source AC such as a commercial AC power source.

In the outlet P of the present embodiment, a plug 200 is used, as shown in Figs. 15A to 15C. The plug 200 includes a main body 201 made of a resin material having an insulating property. A cord 210 is pulled from a rear end surface (a right side surface in Fig. 15B) of the main body 201. Here, the cord 210 is a three core cord in which three insulation coating wires are disposed within one insulation tube, and two of three insulation coating wires are used for connecting a voltage electrode and the remaining one is used for connecting a ground electrode.

At the front from a front end surface (a front end surface, a left surface 201a in Fig. 15B) of the main body 201, total three plug blades of two flat- shaped plug blades 202 and a round bar-shaped plug blade 203 are protruded. Here, the plug blades 202 are plug blades for a voltage electrode, and the plug blade 203 is a plug blade for a ground electrode. In the main body 201, two plug blades 202 are connected to one end of two insulation coating wires for a voltage electrode of the cord 210, and the plug blade 203 is connected to one end of an insulation coating wire for a ground electrode of the cord 210.

The plug 200 is widely distributed by a standard such as Japanese Industrial Standards (JIS) and therefore a detailed description thereof will be omitted.

As shown in Fig. 14, the outlet P has a main body 101. The main body 101 is a resin molded product made of, for example, a resin material having an insulating property and is formed in a rectangular parallelepiped shape. Two sets of a set of three plug blade insertion holes 110a, 110b, and 111 are installed in one surface 101a (one surface of a thickness direction, a front surface of a sheet in Fig. 14) of the main body 101. That is, the outlet P of the present embodiment is a so-called double outlet that can simultaneously use two plugs 200. The plug blade insertion holes 110a and 110b are plug blade insertion holes for a voltage electrode, and the plug blades 202 for a voltage electrode of the plug 200 are respectively inserted thereto. Further, the plug blade insertion hole 111 is a plug blade insertion hole for a ground electrode, and the plug blade 203 for a ground electrode of the plug 200 is inserted thereto. The main body 101 is buried into a wall surface

(inner wall surface) of a house (not shown) in a state in which one surface 101a thereof is exposed and thereby the outlet P is installed in the wall surface (inner wall surface) of the house.

A wire insertion hole (not shown) for inserting a wire for a power source AC is formed in the other surface (the other surface of a thickness direction) of the main body 101. As shown in Fig. 13, the main body 101 includes a plurality of blade receiving portions 102 (two in the shown embodiment), a terminal 103, a plurality of switches 104 (two in the shown embodiment) , a plurality of position detection units 105 (two in the shown embodiment) , and a controller 106. Further, in the following description, two blade receiving portions 102 are distinguished into symbols 102A and 102B, as needed, two switches 104 are distinguished into symbols 104A and 104B, as needed, and two position detection units 105 are distinguished into symbols 105A and 105B, as needed.

The blade receiving portion 102 has a pair of power supply blade rests 102a and 102b contacting with each of the plug blades 202 inserted into the plug blade insertion holes 110a and 110b. Each of the blade rests 102a and 102b includes a pair of blade receiving springs for clamping the plug blades 202. Further, the blade receiving portion 102 includes a ground blade rest (not shown) contacting with the plug blade 203 inserted into the plug blade insertion hole 111. The ground blade rest includes a pair of blade receiving springs for clamping the plug blade 203. The blade receiving portion 102 is formed in a desirable shape according to a shape of the plug blades 202 and 203 of the plug 200 to use. A well-known blade receiving portion can be used as the blade receiving portion 102 and therefore a detailed description thereof will be omitted. [0021] -08P01128 The terminal 103 has a pair of power supply terminals 103a and 103b connected to a wire for a power source AC inserted into the wiring insertion hole. Further, the terminal 103 has a ground terminal (not shown) connected to a ground wire. One terminal 103a of the terminal 103 is electrically connected to one blade rest 102a of the blade receiving portions 102A and 102B, and the other terminal 103b is electrically connected to the other blade rest 102b of the blade receiving portions 102A and 102B. That is, two blade receiving portions 102A and 102B are connected in parallel between the terminals 103a and 103b. Further, for example, a connection terminal shape and conventional well- known terminal shapes can be used for a pair of power supply terminals 103a and 103b and a ground terminal and therefore a detailed description thereof will be omitted.

The switch 104 provides a control signal (electric signal) of a device such as a relay and can selectively switch a closed state and an open state. In the present embodiment, the switch 104A is inserted between one blade rest 102a of the blade receiving portion 102A and one terminal 103a of the terminal 103. Further, the switch 104B is inserted between one blade rest 102a of the blade receiving portion 102B and one terminal 103a of the terminal 103. The switch 104 is inserted into an electric circuit between the blade receiving portion 102 and the terminal 103, thereby converting an electrical connection state between the blade receiving portion 102 and the terminal 103.

The position detection unit 105 is, for example, a micro switch. The micro switch has, for example, a pair of fixing contact points (not shown) , a moving contact (not shown) having a pair of moving contact points for contacting with and being separated from each of the pair of fixing contact points, a bias spring (not shown) for biasing the moving contact so as to separate the moving contact point from the fixing contact point, and a manipulation piece 105a

(see Figs. 14 and 15A) manipulating the moving contact. In the position detection unit 105, when the manipulation piece 105a is pushed by a predetermined amount while resisting to a pressing force of the bias spring, a pair of moving contact points of the moving contact and a pair of fixing contact points, respectively, contact and thereby the pair of fixing contact points are short-circuited by the moving contact.

The position detection unit 105 is used for detecting a position of the plug 200. As shown in Fig. 14, an opening 112 for protruding the manipulation piece 105a of the position detection unit 105 from the outside of the main body 101 is formed in one surface 101a of the main body 101. In the shown embodiment, the opening 112 is formed in a middle portion between a pair of plug blade insertion holes 110a and 110b.

Thereby, when connecting the plug 200 to the outlet P, the manipulation piece 105a is pushed by the plug 200. If the manipulation piece 105a is pushed more than a predetermined amount by the plug 200, a pair of fixing contact points of the position detection unit 105 are short- circuited. Therefore, a position of the main body 101 of the plug 200 can be detected according to whether a pair of fixing contact points of the position detection unit 105 is short-circuited. In the present embodiment, when the plug 200 is positioned within a prescribed range, a protruding amount of the manipulation piece 105a is set from one surface 101a of the main body 101a so that a pair of fixing contact points of the position detection unit 105 is short- circuited. Here, the prescribed range is a range that can be regarded as the plug 200 is normally connected to the outlet P, and in the present embodiment, the prescribed range is a range in which the plug blades 202 of the plug 200 contact with the blade receiving portion 102, and a distance d (i.e. a distance between one surface 101a of the main body 101 and the front end surface 101a of the main body 201 of the plug 200) between one surface 101a of the main body 201 and the plug 200 is a range less than a predetermined distance. In the present embodiment, the predetermined distance is a distance in which a finger cannot be inserted into a gap between one surface 101a of the main body 101 and the plug 200. Further, the distance in which a finger cannot be inserted is set to a distance that can fill a gap required according to, for example, an installing place or a use form of the outlet P. For example, if the outlet P is installed within a house, the distance in which a finger cannot be inserted is set to a distance in which a child's finger cannot be inserted.

The controller 106 controls to switch the switches 104A and 104B and includes a determination unit 106a and a switching controller 106b. The controller 106 is, for example a micro-computer (microcontroller, widely called as a CPU) , and a program stored in a memory unit is executed by the CPU and is used by the determination unit 106a and the switching controller 106b. Further, the controller 106 includes a power source unit (not shown) for generating operation power thereof and driving power of the switch 104 using electric power of a power source AC. Because the power source unit obtains electric power from between the switch 104 and the terminal 103, the power source unit can obtain electric power even when the switch 104 is opened.

The determination unit 106a monitors a potential difference between a pair of fixing contact points of each of two position detection units 105A and 105B and determines whether a pair of fixing contact points is short-circuited. If a pair of fixing contact points is short-circuited, the determination unit 106a determines that the plug 200 is positioned within a prescribed range, and if a pair of fixing contact points is not short-circuited, the determination unit 106a determines that the plug 200 is positioned outside a prescribed range. That is, the determination unit 106a determines whether the plug 200 is positioned within a prescribed range in each of the position detection unit 105 based on detection results of each of the position detection units 105A and 105B. The switching controller 106b outputs a control signal of each of two switches 104A and 104B according to a determination result of the determination unit 106a, thereby- converting an open state and a closed state of each of the switches 104A and 104B. Specifically, if the determination unit 106a determines that the plug 200 is positioned within a prescribed range, the switching controller 106b closes the switch 104 (converts from an open state to a closed state) . In this case, because a current flows between the blade receiving portion 102 and the terminal 103, power can be supplied from a power source AC to the blade receiving portion 102. If the determination unit 106a determines that the plug 200 is not positioned within a prescribed range, the switching controller 106b opens the switch 104 (converts from a closed state to an open state) . In this case, because a connection between the blade receiving portion 102 and the terminal 103 is intercepted, power cannot be supplied from the power source AC to the blade receiving portion 102.

As described above, the outlet P of the present embodiment includes a main body 101 having plug blade insertion holes 110a and 110b for inserting the plug blades 202 of the plug 200 at one surface 101a thereof, a blade receiving portion 102 for contacting with and maintaining the plug blades 202 inserted into the plug blade insertion holes 110a and 110b, a terminal 103 connected to the power source AC, a switch 104 inserted into an electric circuit between the blade receiving portion 102 and the terminal 103, a position detection unit 105 for detecting a position of the plug 200, and a controller 106 having the determination unit 106a and the switching controller 106b and for controlling the switch 104 according to a detection result of the position detection unit 105.

Next, an operation of the outlet P of the present embodiment will be described with reference to Figs. 15Ato 15C. Further, because the same operation is performed even when connecting the plug 200 to any of two sets of plug blade insertion holes of the main body 101, the following description describes only an operation of the position detection unit 105A, and a description of an operation of the position detection unit 105B will be omitted. When the plug 200 is not connected to the outlet P, the manipulation piece 105a of the position detection unit 105A receives a pressing force of a bias spring and protrudes from one surface 101a of the main body 101, as shown in Fig. 15A. In this case, a pair of fixing contact points of the position detection unit 105 is short-circuited. In this case, because the determination unit 106a determines that the plug 200 is positioned outside a prescribed range, the switching controller 106b sets the switch 104A to an open state.

Next, when continuing to insert the plug blades 202, 202, and 203 of the plug 200 into the plug blade insertion holes 110a, 110b, and 111 of the outlet P from a state shown in Fig. 15A, the plug blades 202 of the plug 200 finally contact with the blade receiving portion 102. In this case, because the switch 104A is in an open state, an arc discharge does not occur between the plug blades 202 and the blade receiving portion 102.

In this state, when the plug 200 is inserted, a front end surface 101a of the main body 201 contacts with the manipulation piece 105a of the position detection unit 105A. When continuing to insert the plug 200, the manipulation piece 105a of the position detection unit 105A moves in a direction in which a moving contact approaches a fixing contact point while resisting a pressing force of a bias spring. As shown in Fig. 15B, when the manipulation piece 105a is pushed by a predetermined amount, a pair of fixing contact points of the position detection unit 105A is short- circuited.

In this case, because the determination unit 106a determines that the plug 200 is positioned within a prescribed range, the switching controller 106b sets the switch 104A to a closed state. Therefore, power supply is started from a time point in which the plug 200 moves from the outside of a prescribed range to the inside of a prescribed range. Accordingly, even if the plug blades 202 of the plug 200 contact with the blade receiving portion 102, when the plug 200 is positioned outside a prescribed range, a potential is not provided to the plug blades 202. Therefore, even if a user contacts with the plug blades 202, the user does not receive an electric shock. When the plug 200 is positioned within a prescribed range, power supply is started and a potential is provided to the plug blades 202. However, a distance d between one surface 101a of the main body 101 and the plug 200 in a prescribed range is a distance in which a finger cannot be inserted into a gap between the one surface 101a of the main body 101 and the plug 200. Therefore, the user cannot contact with the plug blades 202 and does not receive an electric shock.

Thereafter, even if the plug 200 is inserted, because a pair of fixing contact points of the position detection unit 105A is short-circuited, the switch 104 is in a closed state. Finally, the plug 200 is inserted up to a position at which the main body 201 contacts with the main body 101 (the front end surface 201a contacts with one surface 101a of the main body 101) and thereby connection of the plug 200 to the outlet P is completed. In a state shown in Fig. 15C, if the plug blades 202, 202, and 203 of the plug 200 are unplugged from the plug blade insertion holes 110a, 110b, and 111 of the outlet P, a pressing force of the manipulation piece 105a by the plug 200 is weakened. Therefore, in a state where the plug 200 is somewhat unplugged, the manipulation piece 105a of the detection unit 105A can be moved to a position at which a pair of fixing contact points of the position detection unit 105A is not short-circuited by a moving contact, by a pressing force of a bias spring.

In this process, when a pair of fixing contact points of the position detection unit 105A is short-circuited by the moving contact, the plug 200 is positioned within a prescribed range and thus a potential is provided to the plug blades 202. However, as described above, a distance d between one surface 101a of the main body 101 and the plug 200 in a prescribed range is a distance in which a finger is not inserted into a gap between the one surface 101a of the main body 101 and the plug 200. Therefore, a user does not contact with the plug blades 202 and does not receive an electric shock. If a pair of fixing contact points of the position detection unit 105A is not short-circuited by the moving contact, the determination unit 106a determines that the plug 200 is positioned outside a prescribed range and thus the switching controller 106b sets the switch 104A to an open state. Therefore, power supply is stopped from a time point at which the plug 200 moves outside a prescribed range from a prescribed range. Therefore, even if the user contacts with the plug blades 202, the user does not receive an electric shock.

Thereafter, even if the plug 200 is unplugged, a connection between a pair of fixing contact points of the position detection unit 105A is intercepted and thus the switch 104 is in an open state. Finally, in the plug 200, the plug blades 202 are discharged to a position that does not contact with the blade receiving portion 102 and thereby the plug 200 is separated from the outlet P. Here, when the plug blades 202 do not contact with the blade receiving portion 102, the switch 104A is in an open state and thus an arc discharge does not occur between the plug blades 202 and the blade receiving portion 102. In the outlet P of the present embodiment having the above-described structure, the plug blades 202 of the plug 200 contact with the blade receiving portion 102, and when the plug 200 is positioned within a prescribed range in which a distance d between one surface 101a of the main body 101 and the plug 200 is less than a predetermined distance, a current flows between the blade receiving portion 102 and the terminal 103, and when the plug 200 is positioned outside a prescribed range, a current flow between the blade receiving portion 102 and the terminal 103 is intercepted. Therefore, when the plug blades 202 of the plug 200 contact with the blade receiving portion 102, or when the plug blades 202 of the plug 200 are separated from the blade receiving portion 102, power is not supplied to the blade receiving portion 102. Accordingly, when the plug blades 202 of the plug 200 are inserted into the blade receiving portion 102, or when the plug blades 202 of the plug 200 are separated from the blade receiving portion 102, an arc discharge does not occur between the plug blades 202 and the blade receiving portion 102.

Therefore, according to the outlet P of the present embodiment, when the plug blades 202 of the plug 200 are inserted into the blade receiving portion 102, or when the plug blades 202 of the plug 200 are separated from the blade receiving portion 102, it can be prevented that an arc discharge occurs and thus the outlet P can be safely used even at a place using a combustible gas. Further, because consumption of the blade receiving portion 102 due to an arc discharge can be prevented, a lifetime of the outlet can be extended.

Accordingly, a predetermined distance in the outlet P of the present embodiment sets a distance d (distance between one surface 101a of the main body 101 and the front end surface 201a of the plug 200) between one surface 101a of the main body 101 and the plug 200 to a distance in which a finger is not inserted into a gap between one surface 101a of the main body 101 and the plug 200. Therefore, when the plug 200 is positioned within a prescribed range, a finger is not inserted into a gap between one surface 101a of the main body 101 and the plug 200. Therefore, when the plug blades 202 of the plug 200 are inserted into the blade receiving portion 102, or when the plug blades 202 of the plug 200 are extracted from the blade receiving portion 102, it can be prevented that a user's finger contacts with the plug blades 202 and the user receives an electric shock, and thus the outlet can be safely used.

Further, when setting the predetermined distance, it is preferable to set the predetermined distance to have a somewhat margin in consideration of a size error of each portion of the main body 101 or the plug 200. Further, when the front end surface 201a of the plug 200 contacts with one surface 101a of the main body 101, the determination unit 106a determines that the plug 200 is positioned within the prescribed range.

Further, in the present embodiment, a micro switch is used as the position detection unit 105, however as the position detection unit 105, a reed switch or a proximity switch can be used in addition to the above-described micro switch.

(Fifth embodiment)

The outlet P of the present embodiment is an outdoor outlet using for, for example, power supply from a power source AC. Even in the outlet P of the present embodiment, the plug 200 shown in Fig. 15A to 15C can be used, as in the first embodiment.

As shown in Fig. 16, the outlet P of the present embodiment includes a main body 101, a blade receiving portion 102, a terminal 103, a switch 104, a position detection unit 105, a controller 106, an electric leakage detection unit 107, and a test manipulation unit 108.

The main body 101 in the present embodiment is formed in a fan-shaped box having a sectional central angle of 90°, as shown in Fig. 17. In the main body 101, the plug blade insertion holes 110a, 110b, and 111 are formed in one surface (a lower surface in Fig. 17) 101a corresponding to one radius of a fan shape (not shown in Fig. 17), as in the fourth embodiment. However, in the main body 101 of the present embodiment, only a set of plug blade insertion holes 110a, 110b, and 111 are formed.

Further, in the main body 101, a support portion 113 is installed in another surface (left surface of Fig. 105) corresponding to a radius of another side of a fan shape. The support portion 113 has a rectangular plate shape and is used for attaching the main body 101 to a wall surface W. Further, a cover 114 for waterproof is installed in an end portion of an opposite side of the support portion 113 side in one surface 101a of the main body 101. The cover 114 suppresses to penetrate, for example a waterdrop to the blade receiving portion 102 within the plug blade insertion holes 110a, 110b, and 111, or to a charging portion of the plug blades 202 and 203 of the plug 200.

The blade receiving portion 102 in the present embodiment includes blade rests 102a and 102b for a voltage electrode and a blade rest (not shown) for a ground electrode, as in the fourth embodiment. Further, the terminal 103 in the present embodiment includes terminals 103a and 103b and a terminal (not shown) for a ground electrode, as in the fourth embodiment. The blade rest 102a and the blade rest 102b are connected to the terminal 103a and the terminal 103b, respectively.

The switch 104 in the present embodiment includes a pair of switching devices 104a and 104b. The switching devices 104a and 104b provide a control signal (electric signal) to devices such as a relay and are a device for selectively converting an open state and a closed state. The switching device 104a is inserted between one blade rest 102a of the blade receiving portion 102 and one terminal 103a of the terminal 103. Further, the switching device 104b is inserted between another blade rest 102b of the blade receiving portion 102A and another terminal 103b of the terminal 103. Accordingly, the switch 104 is inserted into an electric circuit between the blade receiving portion 102 and the terminal 103. Thereby, an electrical connection state between the blade receiving portion 102 and the terminal 103 can be converted. Further, because an operation of the switching devices 104a and 104b is interlocked, the switch 104 has one of a state where the switching devices 104a and 104b are opened and a state where the switching devices 104a and 104b are closed.

The position detection unit 105 in the present embodiment is a micro switch, as in the fourth embodiment. In the present embodiment, in a state where no load is loaded, the position detection unit 105 is received within the main body 101 so that a manipulation piece 105a thereof protrudes to the outside from the opening 112 provided in one surface 101a of the main body 101. Further, in the present embodiment, the opening 112 is formed in a middle portion between a pair of plug blade insertion holes 110a and HOb.

Accordingly, even in the outlet P of the present embodiment, when connecting the plug 200, the manipulation piece 105a is pushed by the plug 200. When the manipulation piece 105a is pushed more than a predetermined amount by the plug 200, a pair of fixing contact points of the position detection unit 105 is short-circuited. In the present embodiment, when the plug 200 is positioned within a prescribed range, as in the fourth embodiment, a pair of fixing contact points of the position detection unit 105 is short-circuited and thus a protruding amount of the manipulation piece 105a from one surface 101a of the main body 101 is set.

The controller 106 in the present embodiment controls to switch respectively the switching devices 104a and 104b of the switch 104 and includes a determination unit 106a and a switching controller 106b. The determination unit 106a and the switching controller 106b are identical to those in the fourth embodiment and therefore a detailed description thereof will be omitted.

The controller 106 in the present embodiment further includes an electric leakage interception unit 106c. Further, the controller 106 is, for example a micro-computer (microcontroller, widely called as a CPU) . And a program stored in a memory unit is executed by the CPU so that the determination unit 106a, the switching controller 106b, and the electric leakage interception unit 106c are operating. Further, the controller 106 in the present embodiment includes a power source unit (not shown) , as in the fourth embodiment .

The electric leakage interception unit 106c is to open the switch 104 when electric leakage occurs. The electric leakage detection unit 107 is used for detecting whether electric leakage occurs. The electric leakage detection unit 107 is, for example a 0-phase converter (ZCT) . An electric circuit between the blade rest 102a and the terminal 103a and an electric circuit between the blade rest 102b and the terminal 103b are inserted into the electric leakage detection unit 107. Therefore, the electric leakage detection unit 107 generates a detection output according to an unbalanced current between the two electric circuits. The electric leakage interception unit 106c determines whether electric leakage occurs using a detection output of the electric leakage detection unit 107 (for example, using whether a magnitude of a detection output exceeds a predetermined critical value) . If electric leakage occurs, the electric leakage interception unit 106c outputs a control signal to each of the switching devices 104a and 104b of the switch 104 and opens the switch 104. However, the outlet device of the present embodiment includes a test manipulation unit 108 for executing an operation test when electric leakage occurs. The test manipulation unit 108 is, for example a push button switch to be turned on while only manipulating. Because the electric leakage interception unit 106c monitors a manipulation state of the test manipulation unit 108, when the test manipulation unit 108 is manipulated (when turned on) , the electric leakage interception unit 106c outputs a control signal to each of the switching devices 104a and 104b of the switch 104 and opens the switch 104. Therefore, the test manipulation unit 108 determines whether the electric leakage interception unit 106c normally operates (whether an electric leakage interception operation normally operates when electric leakage occurs) . As described above, in the outlet P of the present embodiment, as in the fourth embodiment, when the plug blades 202 of the plug 200 contact with the blade receiving portion 102 and when the plug 200 is positioned within a prescribed range in which a distance between one surface 101a of the main body 101 and the plug 200 is less than a predetermined distance, a current flows between the blade receiving portion 102 and the terminal 103, and when the plug 200 is positioned outside a prescribed range, a current flow between the blade receiving portion 102 and the terminal 103 is intercepted. Further, as in the fourth embodiment, the predetermined distance sets a distance d (a distance between one surface 101a of the main body 101 and a front end surface 201a of the plug 200) between one surface 101a of the main body 101 and the plug 200 to a distance in which a finger cannot be inserted into a gap between one surface 101a of the main body 101 and the plug 200. Therefore, according to the outlet P of the present embodiment , the same advantage as that of the fourth embodiment can be obtained.

In addition, because the outlet P of the present embodiment includes a electric leakage detection unit 107 for detecting electric leakage, when electric leakage is detected by the electric leakage detection unit 107, the controller 106 controls the electric leakage interception unit 106c to open the switch 104. Therefore, in the outlet P of the present embodiment, when electric leakage occurs, the switch 104 opens and thus electrical connection between the terminal 103 and the blade receiving portion 102 is intercepted. Therefore, electric shock, fire, or damage of electric power that may be caused by electric leakage can be prevented, and the outlet P can be safely used. Further, the electric leakage detection unit 107 and the electric leakage interception unit 106c can be used for the outlet P of the fourth embodiment.

The outlet P of the present embodiment is used, for example for charging an electric vehicle C, as shown in Fig. 18. Here, the electric vehicle indicates a vehicle in which a battery (rechargeable battery) and a motor are mounted and includes a so-called hybrid vehicle in which an internal combustion engine (gasoline engine) and a motor are mounted and a plug-in hybrid vehicle. An inlet for power supply is installed in the electric vehicle C. A desirable shape or structure of an inlet of the electric vehicle is selected according to a specification of a battery mounted in the electric vehicle C. Further, when a charging device (not shown) for converting AC to DC and charging the battery is mounted in the electric vehicle C, the inlet is formed to connect to an AC power source (for example, a commercial power source of AC 200V having a frequency of 50Hz or 60Hz) .

A cord set S (hereinafter, abbreviated to as a ^λcord set') for charging the electric vehicle is used for charging the battery of the electric vehicle C. The cord set S is a power source cord set using for connecting an outlet corresponding to an AC power source and an inlet of the electric vehicle. The cord set S shown in Pig. 18 includes a cord (cord of a power source side) 210 in which the plug 200 is provided, a cord (cord of a load side) 230 in which the connector 220 connected to the inlet of the vehicle C is provided, and an electric leakage interception device 240 for intercepting an electric circuit between the cords 210 and 230 when electric leakage occurs by connecting the cord 210 of the power source side and the cord 230 of the load side.

Further, an example shown in Fig. 18 is an use example of the outlet P, use of the outlet P is not limited to charge of the electric vehicle C, and the outlet P can be used for several use such as a power supply light installed in a garden .

However, the outlet P of the present embodiment may be, for example an outlet shown in Fig. 19. In Fig. 19, the upside of Fig. 19 is defined as the upside of the main body 101, the downside of Fig. 19 is defined as the downside of the main body 101, the left side of Fig. 19 is defined as the rear of the main body 101, and the right side of Fig. 19 is defined as the front of the main body 101.

In the outlet P shown in Fig. 19, a structure of the main body 101 is different from that of the outlet P of Fig. 17. Further, other structures are similar to those shown in Fig. 17 and therefore a detailed description thereof will be omitted.

The main body 101 shown in Fig. 19 has a support portion 113, as shown in Fig. 17. Further, because the main body 101 shown in Fig. 19 has one surface 101a in which a normal direction thereof is inclined downward, the recess 101b is formed in the one surface 101a. The recess 101b is formed in a size to house a front end portion of the main body 201 of the plug 200. In the bottom of the recess 101b, the plug blade insertion holes 110a, 110b, and 111 are formed (not shown in Fig. 19), as in the fourth embodiment. Further, a set of plug blade insertion holes 110a, 110b, and 111 are formed in the main body 101 shown in Fig. 19, as in the main body 101 shown in Fig, 17. Further, an opening 112 is formed in a middle portion between a pair of plug blade insertion holes 110a and 110b, and the manipulation piece 105a of the position detection unit 105 is protruded from the opening 112.

Therefore, in the outlet P shown in Fig. 19, the same advantage as that of the outlet shown in Fig. 17 can be obtained.

Further, the outlet P shown in Fig. 19 includes a waterproof cover 115. The waterproof cover 115 has a flat plate portion 115a of a rectangular plate shape having a size that can cover one surface 101a of the main body 101. The flat plate portion 115a is rotatably attached to an upper end side of one surface 101a of the main body 101 using a width direction (a normal direction of a sheet in Fig. 19) of the main body 101 as a rotation axis direction. Here, a rotation range of the flat plate portion 115a is a range between a closed position (a position indicated by a dotted line in Fig. 19) that covers one surface 101a of the main body 101 and an open position (a position indicated by a solid line in Fig. 19) that releases one surface 101a of the main body 101. Further, the flat plate portion 115a uses a bias unit such as a twist coil spring and is biased to always position at a closed position. In order to fix the flat plate portion 115a at a closed position, a fixing piece 116 is installed at a lower end side of one surface 101a of the main body 101. The fixing piece 116 is formed in a claw shape, and when the flat plate portion 115a is positioned at a closed position, an end portion of the fixing piece 116 is latched to an edge of a surface opposite to one surface 101a side in the flat plate portion 115a, and thus the fixing piece 116 fixes the flat plate portion 115a at a closed position.

As described above, because the waterproof cover 115 is always positioned at a closed position, in a state where the plug 200 is not connected, one surface 101a of the main body 101 is covered by the flat plate portion 115a. Therefore, it can be surely prevented that a waterdrop penetrates to the blade receiving portion 102 within the plug blade insertion holes 110a, 110b, and 111, or to the plug blades 202, 202, and 203 of the plug 200.

When connecting the plug 200 to the outlet P shown in Fig. 19, it is preferable that after the waterproof cover 115 is moved from a closed position to an open position, the plug blades 202, 202, and 203 of the plug 200 are respectively inserted into the plug blade insertion holes 110a, 110b, and 111. In this case, because the flat plate portion 115a is biased to position at a closed position, the flat plate portion 115a elastically contacts with a rear end portion of the main body 201 of the plug 200. In this state, the waterproof cover 115 performs the same function as that of the cover 114 shown in Fig. 17. That is, it can be suppressed that a waterdrop penetrates to the blade receiving portion 102 within the plug blade insertion holes 110a, 110b, and 111, or to the plug blades 202 and 203 of the plug 200. Further, an unplugging prevention rib 115b is integrally protruded in the flat plate portion 115a of the waterproof cover 115. The unplugging prevention rib 115b is formed to contact with a rear end surface of the main body 201 of the plug 200 connected to the outlet P. Therefore, when the plug 200 is connected to the outlet P, it can be prevented that the plug 200 is unplugged by the unplugging prevention rib 115b. In the foregoing description, the outlet P according to an embodiment of the present invention is described, however this is an illustration. Therefore, the present invention is not limited to the above described embodiments, and may be embodied in various forms without departing from the spirit or scope of the present invention. For example, a shape of the main body 101, or a shape of the plug blade insertion holes 110a, 110b, and 111 can be formed to correspond to several standards (for example, JIS C8303-1993 etc.) .

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. An outlet including an outlet body for supplying electric power to a plug including a plug case having a front surface from which plug blades are protruded and a rear surface opposite to the front surface in an insertion direction of the plug blades, the outlet body having an insertion surface in which plug blade insertion slots for inserting the plug blades of the plug, the outlet comprising: a door body provided in the outlet body, the door body being movable between a closed state in which it covers the plug blade insertion slots and an open state in which it is separated from the plug blade insertion slots, and the door body having a holding portion for keeping the plug blades inserted into the plug blade insertion slots when the plug blades of the plug are inserted into the plug blade insertion slots.

2. The outlet of claim 1, further comprising a bias unit for biasing the door body toward the plug blade insertion slots, wherein the bias unit biases the door body to keep the holding portion in contact with the plug while the plug blades of the plug are inserted into the plug blade insertion slots, and the bias unit biases the door body to cover the plug blade insertion slots while the plug blades of the plug are not inserted into the plug blade insertion slots .

3. The outlet of claim 1 or 2 , wherein the holding portion has a contact portion adapted to contact with the rear surface of the plug case.

4. The outlet of claim 3, wherein the door body has a door main body for covering the entire plug blade insertion slots, the holding portion has an inclined portion in which a protruding amount thereof from the door main body increases in the insertion direction of the plug, and when the plug blades of the plug are being inserted into the plug blade insertion slots, the door body is moved in a direction of being separated from the plug blade insertion slots by the plug contacting with the inclined portion.

5. The outlet of claim 4, wherein the contact portion is provided in a substantially 'L' shape contacting with the plug, the contact portion being extended from the inclined portion in the plug insertion direction.

6. The outlet of claim 3, wherein the door body has a door main body of a substantially flat plate shape for covering the plug blade insertion slots, the holding portion has an inclined portion in which a protruding amount thereof from the door main body increases in the insertion direction of the plug, and when the plug blades of the plug are inserted into the plug blade insertion slots, the plug blades are kept inserted into the plug blade insertion slots by the inclined portion contacting with the plug.

7. The outlet of claim 1 or 2 , wherein when the plug blades of the plug are inserted into the plug blade insertion slots, the door body covers at least a part of a side surface of the plug.

8. The outlet of claim 1 or 2, wherein the insertion surface of the outlet body has a recess portion depressed in the insertion direction of the plug, the recess portion having a bottom surface in which the plug blade insertion slots are provided and a side surface enclosing the bottom surface, the plug is located adjacent to the side surface when the plug blades of the plug are inserted into the plug blade insertion slots, and the holding portion is received in the recess portion when the door body is in the closed state .

9. The outlet of claim 1 or 2 , further comprising an elastic member provided in at least one of the door body and the outlet body to surround the plug blade insertion slots, wherein when the door body is in the closed state, the elastic member contacts in a compressed state with a peripheral portion surrounding the plug blade insertion slots in the outlet body.

10. The outlet of claim 1 or 2, wherein when the door body- is in the closed state, the holding portion blocks the plug blade insertion slots by contacting with entire peripheral portions around the plug blade insertion slots .

11. The outlet of claim 4, wherein when the door body is in the closed state, the holding portion blocks the plug blade insertion slots by contacting with entire peripheral portions around the plug blade insertion slots .

12. An outlet device comprising: a main body having at a surface thereof a plug blade insertion holes for inserting plug blades of a plug; a blade receiving portion for contacting with and maintaining the plug blades inserted into the plug blade insertion holes; a terminal for contacting with a power source; a switch arranged in an electric circuit between the blade receiving portion and the terminal; a position detection unit for detecting a position of the plug; and a controller for controlling the switch according to a detection result of the position detection unit, wherein the controller comprises : a determination unit for determining, based on the detection result of the position detection unit, whether the plug blades of the plug contact with the blade receiving portion and the plug is positioned within a prescribed range in which a distance between the surface of the main body and the plug is less than a predetermined distance; and a switching control unit for closing the switch when it is determined that the plug is positioned within the prescribed range, and for opening the switch when it is determined that the plug is not positioned within the prescribed range.