WO2007007432A1

WO2007007432A1 - Base unit for dual wiring system

Info

Publication number: WO2007007432A1
Application number: PCT/JP2005/024200
Authority: WO
Inventors: Masahiro Yamamoto; Takeshi Ueno; Kazufumi Oogi; Kenichi Yoneyama; Hideshi Hamaguchi
Original assignee: Matsushita Electric Works, Ltd.
Priority date: 2005-07-08
Filing date: 2005-12-22
Publication date: 2007-01-18
Also published as: KR20080031353A; KR100975259B1; JP4311445B2; US8138636B2; JP2008533952A; KR100944743B1; US20090209136A1; KR100987686B1; JP2008533953A; WO2007007427A1; US20090110407A1; WO2007007431A1; JP4311446B2; KR100969902B1; KR100975260B1; US8238755B2; JPWO2007007427A1; KR20080031923A; US20090051505A1; KR20080035590A

Abstract

A base unit suitable to improve easy exchangeability of a function unit in a dual wiring system is provided. The base unit is mounted in a wall surface of a structure, and connected to both of an electric power line and an information line previously installed in the structure. The base unit has a module port, which is detachably connected to a module connector of the function unit to simultaneously establish both of supplying the electric power from the base unit to the function unit, and making a signal transmission between the base unit and the function unit, thereby enabling the function unit to provide at least one of functions for supplying electric power from the electric power line, outputting information from the information line and inputting information into the information line when connected with the base unit.

Description

DESCRIPTION BASE UNIT FOR DUAL WIRINTG SYSTEM

TECHNICAL RIELD

The present invention relates to a dual wiring system, which can be used for the supply of electric power and the input and output of information through an electric power line and a signal line installed in a structure . BACKGROUND ART

Due to popularization of the Internet, it has been demanded to ensure the accessibility to information networkis at many locations in building structures such as general houses and office buildings. For example, Japanese Patent Early Publication [lcokai] No. 11-187154 discloses a multimedia -wiring system having a distribution board for controlling an electric power line and various kinds of signal lines installed, in a structure in a centralized control marxner, and a multimedia receptacle panel, which is adapted in. use to be mounted in an indoor wall surface, and connected to the distribution panel through the electric power line and the signal lines. For example, the multimedia receptacle panel has a power receptacle for supplying commercial electric power to an electric appliance, receptacle for receiving broadcasting programs such as ground wave broadcasting, satellite broadcasting, and cable television, modular jacks for analog and digital lines used for the Internet and telephone comnxunication. By use of^" this multimedia wiring system, the convenience of multimedia products is enhanced to obtain comfortable living and working environments in the information society.

By trxe way, the above-described multimedia receptacle panel is usually mounted in the wall surface, and connected to the electric power line and the signal lines ixnder construction works of the building structures. This means that the functions of the multimedia receptacle panel are determined at the time of the construction works. Therefore, after the construction works are finished, it is difficult to add a new function to trxe multimedia receptacle panel or exchange a part of the functions of the existing multimedia receptacle panel for another function. In addition, when exchanging the existing multimedia receptacle panel for another multimedia panel, a repair work is needed. However, such a repair work is not easy for general users to perform, and the costs of the repair work become a burden to the user.

Thus, the conventional multimedia receptacle paneL still has plenty of room for improvement from the viewpoints of easy exchangeability and function expandability. SUMMARY OF THE INVENTION

Therefore, a. primary concern of the present invention is to provide a base unit suitable for a dual wiring system with improved function expandability and easy exchangeability.

That is, the ^"base unit for the dual wiring system of the present invention is adapted in use to b»e mounted in a wall surface of a structuire, and connected to both of an electric power line and an information line installed in the structure. The base unit is characterized by having one of a module connector and a module port, which is detachably connected to tne other one of the module connector and the module port formed in a function unit to simultaneously establish both of supplying the electric power from the base unit to the function unit, and making a signal transmission, between the base unit and the function unit, thereby enabling the function unit to provide at least one of functions for supplying an electric power from the electric power line, outputting information from the information line, and inputting information into the information line.

According to the present invention, since both of tne supply of electric power from the base unit to the function unit and the mutual communication of the information signal between the bs.se unit and the function unit can be simultaneously obtained by the connection between the module connector and the module port, a general user can easily exchange the function unit already connected to the base unit for anottαer function unit without performing a laborious repair work. In addition, when a plurality of base omits are mounted in wall surfaces at plural locations in th_e structure, each of the base units are sharable among a plurality of function, units having various kinds of functions such as receptacle, switch, sensor, controller, monitor and speaker. Therefore, an increased degree of freedom of layout of the function units provides comfortable and convenient living and working environments to meet the user's needs.

In the above base unit for the dual wiring system, it is preferred that the module connector and the module port have a pair of an electric power connector and an electric power port, which are detachably connected to each other to supply the electric power from the base unit to the function unit, and a pair of an information signal connector and an information signal port, which are detachably connected to each other to make the signal transmission between the base unit and the function unit. In particular, it is preferred that the electric power port and the electric power connector are configured to supply the electric power from the base unit to the function unit by means of electromagnetic coupling, and the information signal port and the information signal connector are configured to make the signal transmission between the base unit and the function unit by means of optical coupling. In this case, since the electric power transmission and the signal transmission between the base unit and the function unit are performed in a noncontact manner by means of the electromagnetic and optical couplings, it is possible to minimize transmission loss of the electric power and/ or the electric signal therebetween, and operate the function unit with reliability.

In addition, it is preferred that the base unit has a housing, which is formed with a rear portion having terminals to be connected to the electric power line and the information line, front portion having at least one of an outlet configured to receive a power plug of an electric appliance, and a switch configured to turn on /off the electric appliance, and a side portion having the one of the module connector and the module port such that the function unit is detachably connected to the base unit in a direction along the wall surface. In this case, it is possible to improve function expandability in the dual wiring system without spoiling the beauty in the interior spaces. Alternatively, the base unit may have a housing, which is formed with a rear portion having terminals to be connected to the electric power line and the information line, and a front portion having the one of the module connector and the module port. Moreover, it is preferred that the base unit of the present invention further includes a joining means configured to mechanically connect the function unit to the base unit. For example, the joining means is formed with an engaging portion sixch as elongated projection and groove formed on the base unit, and a joining member configured to slidably contact the engaging portion and make the mechanical connection between the base unit and the function unit when a region of the joining member is engaged to the engaging portion of the base unit and the remaining region of the joining member is enga_ged to an engaging portion formed on the function unit. Im this case, it is possible to improve the reliability of the supply of electric power and the mutual comrnvmication of the information signal between the base unit and the function unit, and prevent an accidental falling of trxe function unit from th.e base unit.

These and additional features of the present invention and advantages brought thereby will become more apparent from the following preferred embodiments, referring to the attached drawings. BRIEF EXPLANATION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a dual wiring system according to a preferred embodiment of the present invention;

FIG. 2 is a schematic circuit diagram of a base unit for the dual wiring system; FIG. 3 is an exploded perspective view of the ba.se unit;

FIG. 4 is a schematic circuit diagram of another base unit comprised of main and gale housings;

FIG. 5 A is a perspective view of the main hoiising of FIG. 4, and FIG. 5B is a module port formed in the gate housing of FIG . 4;

RIG. 6 is a schematic circuit diagram of a function unit for the dual wiring system; RIGS. 7A and 7B are front and rear perspective views of the function unit connected to the base unit;

RIG. 8 is a perspective view of a plurality function units connected to tlxe base unit; RIG. 9 is a plan view of an attachment plate for fixing the base unit to a_ switch box; RIG. 1OA is an exploded perspective view illus"trating how to connect the function unit to the base unit, and FIG. 1OB is a perspective view of a joining member;

FIGS. 1 IA and 1 IB are front and side views of the function unit according to a first modification of the embodiment, and FIG . HC is a perspective view illustrating how to use the joining member;

FIGS. 12A and 12E5 are front views of another examples of the function unit;

FIGS. 13A and 13B are perspective views illustrating how to make a connection between the base unit and the function unit according to a second modification of the embodiment; ajad

FIGS. 14A to 14C are front and side views of the function unit according to a third modification of the embodiment.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENNTS OF THE INVENTION

A base unit for dual wiring system of the present invention, is explained in detail according to the following preferred embodiments.

As shown in FIG. 1 , the dual wiring system of this embodiment has a power supply line Ll and an information line L2 installed in a building structure, which are connected to commercial power souxce AC and the internet network NT through a distribution board 1, switch boxes 2 embedded in wall surfaces at plural locations in the building structure, base units 3 mounted in the switch boxes and connected to the power supply line Ll and the information line L2, and a plurality of function units 4 each having the capability of providing at least one of functions for supplying electric power from the electric power line Ll, outputting information from the information line L2 and inputting information into the infojrmation line L2 when connected with one of the base units 3. In the present specification, the wall is not limited to the sidewall formed ^"between adjacent rooms. That is, the wall includes exterior wall and interior wall of the building strαcture, and the interior wall includes the sidewall, ceiling and floor. In FIG. 1, "MB" designates a main breaker, "BB" designates a branched breaker, and "GW" designates a gateway (e.g., router or built-in hub).

As shown in FIG. 2, each of the base units 3 has terminals (30a, 32a) connected to the power supply line Ll and the information line L2, and bus-wiring terminals (30b, 32b) at its rear surface. As shown in FIG.3, the base unit 3 is fixed to the switch box 2 by use of conventional fastening means such as screws. In FIG. 3, the nximeral 12 designates a. cosmetic cover detacrαably attached to a front surface of the base unit, and the numeral 11 designates a receptacle cover independently provided from the cosmetic cover 12. Circuit components of the base unit 3 are designed to transmit trie electric power and the information signal to the function xαnit 4. For example, tfcie base unit 3 of FIG. 2 is provided with an AC/AC converter 60, DC power section 61, transceiver section. 62, E/O converter 63, and O/E converter 65.

The AC /Ac converter 60 converts commercial AC voltage to a lower AC voltage having an increased frequency, and applies the lower Λ.C voltage to a coil 72 wound around a core 70. The DC power section 61 generates an operating voltage of the internal circuit components from a stable DC voltage obtained by rectifying and smoothing the lower AC voltage. The transceiver section 62 transmits and receives the information signal for ena/bling the mutual communication through the information line L2. The E/O converter 63 converts the information signal received from ttie information line L2 to an optical signal, and outputs the optical signal though, a light emitting device (LED) 64. On the other hand, the O/E converter 65 receives the optical signal provided from the outside, e.g., the function unit 4 by a light receiving device (PD) 66, and converting the received optical signal into the information signal to transmit it to the transceiver section 62. In FIG. 2, the numeral 67 designates a function section such as power receptacles. If necessary, the function unit 6T may be omitted.

In addition, another base unit 3 shown in FIG. 4 may be used. This base unit 3 is formed, with a gate housing 31 having terminals (3. Oa, 32a, 30b, 32b) connected to ttxe power supply line Ll and the information line L2, and a main housing 33 detachably connected to "the function unit 4. The gate housing 31 and the main housing 33 have a pair of a module port 34 and a. module connector 42, which are detachably connected to each other to simultaneously establish both of supplying the electric power from the gate housing to the main housing, and making a. signal transmission between the gate housing and the main housing- In addition, a. function unit having trie module connector 42 may be detachably attached to ttαe module port 34 of the gate housing 31 in pla.ce of the main housing 33. In this case, the gate housing 31 having the module port 34 satisfies the definition of tlie base unit.

The module port 34 formed at its front surface of the gate housing 31 is composed of an electric power port 34a for supplying the electric power and an information signal port 34b for accessing the information lime, as shown in FIG. 5B . In the module port 34, an arrangement of the electric power port 34a and the information signal port 34b, and a shtape of each of those ports are standardized (normalized) in the dual wiring system. For example, as shown in FIG. 5B, each of^" the electric power port 34a and the information signal port 34b is configured in a_ substantially rectangular shape such, that they are arranged in parallel to each, other.

On ttie other hand, the module connector 42 formed at its rear surface of^" the main hcmsing 33 is composed of an electric power connector 42a and arL information signal connector 42b, as shown in FIGS. 4 and 5A. In the module connector 42, an arrangement of the electric power connector 42a and the information signal connector 42b, and a shape of each of those connectors are standardized (normalized) in the dual wiring system of this embodiment. For- example, as shown in FIG. 5A, each of the electric power connector 42a and the information signal connector 42b is configured in a substantially rectangulatr shape such that they are arranged in parallel to each other.

In trxis embodiment, the module port 34 also has a. guide portion 35 sucta. as a ring-lik:e wall or a ring-like grocrve extending around the electric power port 34a and the information signal port 34b. This guide portion 35 is formed to be engageable to an engaging portion 45 such as a ring-l-Lke wall of the module connector 42, which is formed on the rear surface of the uxain housing 33. Since the electric power connector 42a and the information signal connector 42b are simultaneously connected to the electric power port 34- a and the information signal port 34-b by simply engaging ttαe engaging portion 45 to the guide portion. 35, it is possible to improve the removability of the main housing 33. The mocLule port 34 and the module connector 42 may be formed by female and irαale connectors.

In addition, the base unit 3 of FIG. 4 is designed to have a sensor function or a controller function as the function section 67. That is, a processing section 68 and I/O Interface 69 are formed between the transceiver section 62 and the function section 67. The processing section 68 has functions of performiixg a signal processing of the information signal received by the "transceiver section 62 to transmit the processed signal to the function section 67 through the I/O interface 69, and receiving the data signal provided from the function section 67 to output as the information signal. Electric power needed to energize the transcedver section 62, processing section 68 and the function section 67 is supplied from, the DC power section 61. When an AC /DC converter for converting the commeircial AC voltage into a required DC voltage is used in place of the AC/ AC converter 60, the DC power section 61 can be omitted. The other circuit components in FIC 4 are substantially the same as them, of FIG. 2. Therefore, duplicate explanations are omitted.

The function unit 4 is optionally designed to provide a desired functiom. by using the electric power provided to the function unit 4 through the base unit 3 and the mutual communication of the information signal between the function unit 4 and the information line L2 through the base unit 3. For example, when the function, unit 4 is connected to the base unit 3 moun-ted in the wall surface at a high position near the ceiling, it preferably has a receptacle function of receLving a plug with nook of a lighting apparatus, security function such as a motion serrisor, temperature sensor, and monitoring camera, or a sound frunction such as speaker. In addition, when the function unit 4 is connected to the base unit 3 mounted in the wall surface at a middle height*, at which the function unit 4 can be easily operated by the user, it preferably has a switch function of turning on/ off the lighting apparatus, control function for electric appliances such as air-conditioning equipments, or display function sucln as liquid crystal display. In addition, -when the function unit 4 is connected to the base unit 3 mounted in the wall surface at a low position near the floor, it preferably has a receptacle function for receiving a plug of an electric appliance such as electric vacuum cleaner, the sound function such as speaker, or a footlight function.

Specifically, as shown in FIG. 6, when the function section 81 is formed by a switch, operation data obtained by operating the SΛvitch is transmitted to the processing section 88 through tlie I/O interface 89. Then the processed data is sent to, for example, an infrared remote controller- (not shown) throughi the transceiver section 87, so that an electric appliance to be controlled is tmrned on/ off by receiving a remote control signal emitted, from the infrared remote controller. In addition, when titαe function section 81 is formed by a sensor, data detected by the sensor is transmitted as the information signal to the inform.ation line L2, and then informed to tlαe user by a required communicator. Whexi the function section 81 is formed by a speaker, sound data provided as the information, signal through the information line L2 is output from the speaker. When the function section 81 is formed by a monitoring camera, compression encoding of image data taken t>y the monitoring camera is performed, and then output as tlie information signal. Furthermore, whexi the function section 81 is formed by a. monitor, image data provided through the information line X2 is decoded, and then displayed on the monitor. When, the function section 81 is simply formed by the power receptacle, the processing section 88 and the I/O interface 8© can be omitted. Thus, since the function units 4 having various kinds of the function sections 81 can be detachably used in the dual wiring system, the degree of freedom of layout of the function units 4 can be remarlkably improved.

The coil 72 wound around the core 70 in the ba.se unit 3 is used as a power transmission means for supplying electric power from the base unit 3 to the function unit 4 in a noncontact manner. That is, tkte coil 72 wound around the core 70 of tlie base unit 3 provic3.es an electromagnetic; coupling portion that xvorks as a first side of a transformer. On the other hand., as shown in FIG. S, the function unit 4 has an electromagnetic coupling portion comprised of a coil 82 wound around a core 80, which works as a secoixd side of the transfoirmer. Therefore, by forming electromagnetic coupling between the base unit 3 an_d the function unit 4, a low AC voltage is induced in the coil 82 of the function unit 4 to achieve trie supply of electric power from the base unit 3 to the function unit 4. In this embodiment, since the low AC voltage having the higher frequency than the commercial AC voltage is obtained by the AC/ AC converter 60, the electromagnetic coupling portions used as the transformer can be downsized.

In. addition, the light emitting device (LED) 64- of the E/ O converter 63 of the base unit 3 is used to transmit the optical signal as the information signal to the function unit 4 in a noncontact manner. In this case, as shown in FIG. 6, a light receiving device (PD) 86 is disposed in the function unit 4 such that the light emitting device 64 of the base unit 3 is in a face-to-face relation with the light receiving device 86 of the function unit 4 when the function unit 4 is connected to the base unit 3. Similarly, to transmit the optical signal as the information signal from the function unit 4 to the base unit 3, the function unit 4 has a light emitting device (LED) 84, which is disposed to be in the face-to-face relation with the light receiving element (PD) 66 of trie base unit 3 when the function unit 4 is connected to the base unit 3. Thus, each of the base unit 3 and the function unit 4 h_as the pair of trie E/O converter (63, 83) and the O/E converter (65, 85) as an optical coupling portion to enable the mutual communication of the information signal therebetween.

A-S shown in FIGS. 2 and 3, the electromagnetic coupling portion X used for the supply of electric power and the optical coupling portion Y used for the mutual communication of the information signal are disposed at a side surface of each of the function units 4 to be spaced from each other by a constant distance. In addition, shapes of the electromagnetic coupling portion X and the optical coupling portion Y are standardized (stylized) to make each of the base i-inits 3 shareable among the function "units 4. In addition, the pair of the electromagnetic coupling portion X and the optical coupling portion. Y are formed at each of both sides of the function unit 4, as shown in FIG. 6. That is, the optical coupling portion Yl formed at one side (e.g., left side) of the function unit 4 is composed of the light receiving device 8& located at the upper side and the light emitting device 84 located at the lower side, and the optical coupling portion Y2 formed at the opposite side (e.g., right side) of the function unit 4 ±s composed of a light emitting device 94 located at the upper side and a light receiving device 96 located, at the lower side.

In this case, even when a plurality of function units 4 are connected in series to the base unit 3, it is possible to ensure the mutual communication of the information signal between, the function units 4 as well as between the function unit 4- and the base unit 3 . It is also preferred th. at a light transparent cover is attacrxed to the respective optical coupling portion (Y, Yl, Y2) to protect the optical devices. As shown in FIG-. 6, the function unit «4 has circuit components for achieving the power supply and the mutual communication of the info-trmation signal between adjacent function units 4. However, since they are substantially the same as the circuit components used in the base unit 3, duplicate explanations of the same circuit components are omitted.

As shown in FIG.3, when the function section 67 (e.g., power receptacle) is formed at the front surface of the base unit 3, and the pair of the electromagnetic coupling portion X and the optical coupling portion Y is formed in the side surface of the base unit 3, the function units 4 can be connected to the base unit 3 along the wall surface (i.e., in parallel with the wall surface). Therefore, it is possible to imprcrve function expandaJbility in the dual wiring system without spoiling the beauty in the interior spaces.

Examples of the function unit(s) 4 connected to the base unit 3 are introduced below. In FIGS. 7A and 7B, the base unit 3 has a special receptacle for a plug with hook of a light±ng apparatus as the function section 67. The function unit 4- connected to the ba.se unit 3 has a function of emitting an infrarecl remote signal. In this case, operation data obtained when another function unit leaving a controller as the function section is operated by a user is transmitted to the functional unit 4 of FIG. 7 A through the information line L2, so that the infrared remote signal is emitted toward an infrared signal receiving portion of an electric appliance such as air- conditioning equipmexit. In FIG. 7A, the numeral 58 designates a protection cover detachably attacned to the side of the fuinction unit 4 to protect the electromagnetic coupling portion X and the optical coupling portion Y when not used. In addition, when the base unit 3 has the power .receptacle, a relay or a semiconductor switch may be connected to a circuit for the power receptacle such that the function of the poweir receptacle can be cancelled when the relay or the semiconductor switch is operated according to a control signal transmitted from another function unit.

In FIG. 8, first to third function units- (4A, 4B, 4C) are connected to the base unit 3. In this case, the base unit 3 nas no function section. The first additional function unit 4A detachably connected to the base unit 3 lias switches for turning on/ off an air-conditioning equipment as the function section 81. The second function unit 4B detachably connected to the first function u_nit 4A has a controller of the air-conditioning equipment as the function section 81. In addition, the third function unit 4C detachably connected to the second function xinit 4B has a main unit of an intercom system as the function section 81.

The first function unit 4A is provided with an operation button Bl, stop button B2, and a CPU section for preparing the data according to the operation of these buttons and transmitting the prepared data to the processing section through the I/O interface. This function unit is preferably used to operate a lighting apparatus. The second function unit 4B is provided with a temperature setting dial 51 for titxe air-conditioning equipment, LCD (liquid crystal display) monitor 52 for displaying the setting tempera-ture, timer switch 53 for operating the air-conditioning equipment for a desired "time period, and a CPU section for preparing operation data according to the operation of the temperatur-e setting dial Sl and the operation of the timer switch 53, transmitting the operation data to the processing section thorough the I/O interface, and preparing the data to be displayed on the LCD monitor 52.

The third function unit 4C is provided with a volume control button B3, speaker 54, mode switch 55 for switching between the transmitter function and the receiver function of the speaker 54, LCD screen 56 for displaying the image taken by a TV camera placed at the entrance, release button B4- for releasing the door lock, and a CPU section having a soxind processing function for the speaker 54, image processing function for the LCD screen 56, and the functions of preparing operation data according to the operations of the release button B4 and the mode switch 55, and transmitting the prepared opera.tion data to the processing section through the I/O interface. The function sections 81 of the function units 4 are not limited to the at>ove examples. For example, a battery charger for electric shaver, electric toothbrush, mobile phone and portable audio player may be formed as the function section. In addition, trie function unit 4 having a handset function of the intercom system may be connected to the base unit 3 mounted in. an exterior wall surface at the entrance.

In the above explanation, the base unit 3 is directly fixed to the switch box 2. If necessary, the base unit 3 may b>e fixed to the switch ^"box 2 through an attachment plate *75, for example, as shown in FIG. 9. In this case, after hooks formed at both sides of the attachment plate 75 are engaged to tine base unit 3, the attachment plate *75 with the base unit 3 is fixed to the switcli box 2 by use of mounting screws. Alternatively, the base unit 3 may be directly fixed in the wall surface by use of exclusive clamps without using the switch box: 2. After the base unit is mounted in, the wall surface, the receptacle cover 11 and the cosmetic cover 12 are attached to the front surface of a Haousing 10 of the base unit 3.

The function unit 4 can be attaclied to the base unit 3 , as shown in FIG. 1OA. That is, the cosmetic cover 12 is firstly removed from trxe base unit 3. In this embodiment;, since the receptacle cover 11 is separately formed from the cosmetic cover 12, the function section 67 such as the power receptacle can be protected from an accidental breakage by the receptacle cover 11 during the connecting and disconnecting operation for the function uunit 4. After the function unit 4 is arranged on the side surface of the base ^"unit 3 such that the electromagnetic coupling portion X and the optical coupling portion Y of the function unit 4 are in the face-to-face relation with them of the base unit 3, the function unit 4 is mechanically coupled to the base unit 3 by use of a joining member 90. The housing (10, 20) of each of the base unit 3 and the function unit 4 has horizontal guide rails (14, 24) at its upper and lower end portions. The numeral IS designates a stopper wall formed in a substantially center position in the longitudinal direction of the guide rail 14. On the other hand, as shown in FIG. 1OB, the joining member 90 has a groove 92, in which ttie guide rails (14, 24) can be fitted.

As showrα in FIG. 1OA, on the condition that the guide rail 14 is fitted in the groove 92, a slide movement of the joining member 90 is performed until the joining member 90 contacts the stopper wall 15. As a result, the joining member 90 is engaged to the base unit 3 over about half length of the joining member. On the other hand, the joining member 9>0 is also engaged to thte function unit 4 in a similar manner to the above over trie remaining length of the joining member. Thus, after the engagements between, the joining member 9© and the base unit 3 and between the joining member 90 and the function unit 4 are finished at both of the upper and lower end portions, cosmetic covers (12, 22) are attached to the front surfaces of^" the base unit and ttie function unit. Since the joining member 90 is held between the cosmetic covers (12, 22) and the hoxisings (10, 20) of the base unit 3 and the function unit 4, it is possible to prevent a_ccidental falling of the joining member 90, and obtain the stable mechanical con-nection therebetween without spoiling the beauty of them.

The followings are modifications of means for obtaining the stable mechanical connection between the base unit 3 and the function unit 4 or between the adjacent furxction units 4.

As showαi in FIGS. HA to 1 1C, the function unit 4 according to a first modification of tlhis embodiment has a pair of male and female connectors (25, 27) at its both sides, each of which is comprised of the electromagnetic coupling portion X and the optical coupling portion Y. In this case, the male and femalle connectors caxi be regarded as ttxe module connector and port. Since the base unit 3 has the same male and female connectors to make the connection with ttαe function unit 4, the electric power transmission and the signal transmission between the t>ase unit and the function unit are performed in a non-conta_-ct manner by means of the electromagnetic and optical couplings. For example, tine male connector 25 is detachably connected to a female connector formed in ttie base unit 3, and the female connector 27 is detachably connected to a male connector formed on another function unit 4. In addition, this function unit 4 has a horizontal groove 26, in which a joining member 9OA having in a similar cross section to the groove 26 can. be fitted. As in the case of the joining member 90 of FIG. 103, one end of the joining member 9OA is inserted into the groove 26 of the function uxrit 4 over about half^" length of the joining member, and also the oth_er end of the join_ing member 9OA is inserted into a groove formed in an adjacent ba_se unit 3 or another function unit 4 over the remaining tialf length of the joinixig member to provide the stable mechanical connection therebetween.

In this modification, since the groove 26 has a substantially trapezoidal section configured such that an opening formed in the rear surface of the function unit 4 corresponds to a narrow side of the trapezoidal section, the falling of tlhe joining member 9OA from the groove 26 can be presented without using tlhe cosmetic coverr. In addition, the xiser can be accessed to the joining member 9OA through the opening of the rear surface of the function unit 4, it is possible to easily perform the slide movement of the joining member 90A in the groove 26. The shape of the groove is not limited to the trapezoidal section on the condition that the joining member 9OA can not removed from the opening formed in the rear surface of the function unit 4.

As shown in FIG. 12A, only the electromagnetic coupling portion X may be formed by the female and male connectors. To ensure the function expandabiLity of the function unit 4, when the male connector is provided at one side of the function unrt, the female connector is provided at the other side thereof. Alternatively, as shown in FIG. 12B, each of tlxe electromagnetic compling portion X and the optical coupling portion Y may be formed by female and male connectors configured in arcuate recess and projection. Thus, when the use of the female and male connectors provides accurate positioming between the adjacent function units, and consequently the reliability of the supply of electric power and the input and output of the information signal is improved.

As a second modification of this embodiment, it is preferred that each of the Tapper and lower end portions of the function units 4 has a tapered end 21 with an engaging groove 23, and a joining member ^0B is configured to slidably contact the "tapered end 21 and have a hook 93 at its one end, which can b>e fitted in the engaging groove 23, as shown in FIG. 13A. In- this case, after the joining member 90B is fitted to the tapered end 21 at each of the upper and lower ends of the function unit, the joining member 9OB is slid toward an adjacent function unit, as shown by the arrows in FIG. 13A. As a result, the stable mechanical connection between the adjacent function units 4 can Toe obtained by use of this joining member 9OB, as shown in FIG. 13B.

As a third modification of this embodiment, it is preferred trxat each of the upper and lower end portions of the function "unit 4 has a concave portion 28 for accommodating a joining member 9OC, arid a cover member 16 pivotally supported at its one end. to the housing 20 of tne function unit 4, as shown in FIGS. 14A- to 14C. The joining member 9OC has a groove 92C, in which a guide rail 24C formed in the concave portion 28 can be slidably fitted. In this case, after the cover member 16 is opened to access the joining member 9OC, the joining member is slid along the guide rail 24C, as in the case of FIG. 1OA. FinalLy, the cover is closed to obtain the sta.t>le mechanical connection between the adjacent function uni^~ts 4. In addition, since the joining memfc>er 9OC is always accommodated in the concave portion 28, there is no worry aboxit loss of the joining member.

As an information-signal transmitting; method available in the dual wiring sys^~tem of the present invention, one of baseband transmission and broadband transmission can be used. In addition, the protocol is not limited to a specific one. For example, sound and visual information signals may be transmitted axid received according to JT-H232 pa.cket to make the mutual communication between the ^"base unit and the handset of the intercom system. In a control system, it is also preferred to use a routing protocol for s. broadcast or a unicsst that controlling can be performed a± a control ratio of 1: 1 or 1: N according to operation data. Alternatively, it is preferred that the protocol used between the base units is different from the protocol used in the function unit connected to the base unit, and. a protocol conversion is performed at the ^"base unit.

As stiown in FIG. 1, since ea.ch of the function units 4 having the various kinds of functions can be detachably connected to a desired one of the base units 3 to simultaneously establish both of the power supply from the base unit 3 to the function unit 4 and the mutual communication of the information signal between the base unit 3 and the function unit 4, a general user can easily exchange the function unit 4 already connected to one of the base units 3 for another one of "the function units without performing a. laborious repair work. In addition, when a plurality of fiαnction units 4 are conn_ected to the base unit 3 along the wall surfia.ee, the function expandability can be fuxther improved without spoiling the beauty in the interior spaces. Thus, the base omit for the dual wiring system of the present invention is effective to provide comfortable and convenient living and workding environments to meet the user's needs in the information society.

Claims

CLAIMS:

1. A base unit for dual wiring system, which is adapted in use to be mounted in a wall surface of a structure, and connected to both of an electric power line and an information line installed in said structure, wherein the base unit has one of a module connector and a module port, which is detachably connected to the other one of said module connector and. said module porrt formed in a function unit to simultaneously establish both of supplying trie electric power from, the base unit to said function unit, and malting a signal trarxsmission between trie base unit and said function unit, tixereby enabling said function unit to prrovide at least one of functions for supplying an electric power from said electric power line, outputrting information froπx said information, line, and inputting information into said iinformation line.

2. The base unit as set forth in claim 1, wherein said module connector and said module port have a pair of an electric power connector- and an electric power^* port, which are detachably connected "to each other to suppty the electric power from the base unit to said function unit, and a pair of an inforπnation signal connector and an information signal port, whicti are detachably conrxected to each other to make the signal transmission between the base unit and said function unit.

3. The base unit as set forth in claim 2, wherein said electric power port and said electric power connector are conJEϊgured to supply the electric power from the base unit to said function unit by means of electromεignetic coupling, and said information signal port and said information signal connector are configαxed to make the signal transmission between the base unit and said function umit by means of optical coupling.

4. The base unit as set forth in claim 1, wherein the base unit has a ho^~using, which is formed with a rear portion having terminals to be connected to said electric power line and said information line, front portion having at least one of an outlet configured to receive a power plug of an electric appliance, and a switcxh configured to turn on/ off the electric appliance, and a side portion having the one of said module connector and said module port such that said function unit is detachably connected to the base unit in a direction aloner said wall surface.

5. The base unit as set forth in claim 1 , wherein the base unit has a hoaising, which is formed with a rear portion having terminals to be connected to said electric power line and said information line, and a firont portion having the one of said module connector and said module port.

6. The base unit as set forth in claim 1 further comprising a joining means configured to mechanically connect said function unit to the base un.it.

7. The base unit as set forth in claim 6, wherein said joining means comprises an engaging portion formed on the base unit, ajnd a joining member configured to slidably contact the engaging portion and make the mechanical connection between the base unit and said function unit when a region of said joining member is engaged to the engaging portion of the base unit and the remaining iregion of said joining member is enga_ged to an engaging poirtion formed on said function unit.