GB1571271A - Enclosure for electrical apparatus - Google Patents

Description

(54) ENCLOSURE FOR ELECTRICAL APPARATUS (71) We, TOKYO SHIBAURA ELEC TRIC COMPANY LIMITED, a Japanese Company, of 72 Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa-ken, Japan, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to an enclosure for electrical apparatus such as switch or control gear.

In recent years electrical switch or control gear apparatus which is mounted in enclosures has become progressively smaller in volume and two-stage enclosure accommodating two sets of apparatus, one above the other, are now common. The door to such enclosures is usually in two parts, one above the other and the instruments for the protection and inspection of the apparatus within the enclosure have been mounted on the outside faces of the two parts of the door.

The space available on each part of the door for mounting the instruments has been reduced to half of what is available on an enclosure having a single full length door and therefore the positioning of the meters and relays, operating switches, lamps, testing terminals and the like has become a problem.

As regards the operating switches, for example, if these are mounted on the top door they are too high and therefore cannot be reached by hand and this causes trouble, whereas if they are mounted on the lower door they are too low and as a result it is not easy to operate them. This applies not only to the operating switches; the same thing can be said of the meters, lamps, testing terminals and the like; on the top door these instruments must be mounted at the bottom, and on the bottom door these instruments must be mounted at the top. Accordingly, even if the top and bottom circuits are exactly the same, the apertures in the doors and the mounting and arrangement of the instruments are different and this was therefore inconvenient from the point of view of standardisation.

An object of this invention is to provide an enclosure for electrical apparatus in which the instruments needed for regular inspection and operation of the apparatus can be arranged at a position in which inspection and operation is easy and in which standardisation during manufacture is not made difficult.

According to the present invention an enclosure for electrical apparatus comprises a box-like structure defining upper and lower chambers each capable of accommodating electrical apparatus, an end wall of the structure comprising separate upper, lower and intermediate level doors, the upper and lower doors providing access to the upper and lower chambers respectively and the intermediate level door being adapted to receive on its outside face electrical instruments, switches and the like associated with electrical apparatus accommodated in the upper and lower chambers.

In order that the invention may be more readily understood it will now be described, by way of example only, with reference to the accompanying drawings in which: Figures 1 (a) and (b) are a front view and a side view respectively showing an embodiment of the enclosed apparatus of this invention.

Figures 2 (a), (b) and (c) are single line connection diagrams showing circuit structures of various enclosed apparatus to which the present invention is applied.

Figures 3 (a), (b) and (c) are front views of enclosed apparatus showing examples of the respective circuit structures shown in Figures 2 (a), (b) and (c) applied to this invention.

Figure 4 is a perspective view showing an example of a control mounting block used in the present invention.

Figure 5 is a perspective view showing an example of apertures in the middle level door used in the present invention.

Figures 6 (a) and (b) are oblique views showing examples of blank panels mounted on unwanted mounting holes shown in Figure 5.

Figure 7 is a perspective view showing a container mounted on an unwanted mounting hole shown in Figure 5, and spare parts accommodated in that container.

Figures 8 (a) and (b) are a front view and a side view respectively showing enclosed apparatus according to another embodiment of this invention.

Figure 9 is a perspective view showing the state in which the top level door and the middle level door of the enclosed switchboard shown in Figure 8 are open.

Figure 10 is a view in section along the line X-X of Figure 9, as seen in the direction of the arrows.

In Figure 1, 1 is a box-like structure forming an enclosure for electrical apparatus, reference 2 indicates circuit breakers provided one in each of an upper chamber la and a lower chamber 1b of the enclosure. Reference 3 are main circuit disconnector units connectible to and disconnectible from the circuit breakers 2. Reference 4 are bus line conductors connected to a power source bus line not shown in the drawing and accommodated in the bus line chamber lc within the enclosure 1.Reference 5 indicates current transformers, 6 are cables, and 7 are zero phase current transformers; these are accommodated in rear bus line chambers 1d and lc within the enclosure 1 as shown in Figure l(b). The front wall of the enclosure has an upper door 8 provid ing access to chamber la, a lower door pro viding access to lower chamber 1b and an intermediate level door 10. The intermediate level door 10 is positioned between the above mentioned top and bottom doors 8 and 9; and instruments needed for regular inspection and control of the apparatus in the enclosure are mounted on the intermediate level door. 11 is a control bus line which is arranged in a position facing the abovementioned door 10, within the enclosure 1.

The following is a description of the struc ture set forth above, applied to various switch boards. An enclosed switchboard can be one of three kinds, according to the way in which it is used, that is to say a main voltage trans former secondary unit for receiving current, as shown in Figure 2 (a), a switchboard unit for distribution as shown in Figure 2 (b), or, if needed, a bus line link unit for linkage between "banks", as shown in Figure 2 (c), and by suitably combining and arranging them it is possible to build up a bank of switchgear.In each of these units the res pective switchboard surface instrument ar rangement is as shown in Figure 3 (a), (b) and (c); firstly, the instruments mounted on top and on the bottom doors are restricted to protective relays (designated by the numerals 67, 49, 50, 51, 27 and 64) and auxiliary relays (AUR) which do not have to be frequently operated and inspected. These relays are not changed whenever this is con venient because of the manner of the operation of the "user", and therefore they can be fixed for each respective unit. Also, as regards the high positions that cannot be reached by hand, and as regards the low positions also, there is no problem in everyday operation, and there is no objection to a structure in which the top level and bottom level doors are exactly the same as regards the mounting positions.Accordingly, standar disation is effected easily for each individual unit. On the other hand, the instruments mounted on the intermediate level door are restricted to instruments other than those set forth above, that is to say to instruments needed for everyday inspection or operation, for example ammeters A, voltmeters V, switch V.S., lamps G.R.O., testing terminals T.T.

and the like. Accordingly, as regards frequent inspection and operation also, operation is easy and a structure can be produced that is outstandingly good as regards human engineer ing also.

Also, the intermediate level door 10 does not have to be opened except for inspection and maintenance of the control circuit parts accommodated at the back of this door, and therefore this door does not have to have elaborate handles 15 like those provided on the top and bottom doors 8 and 9, and it is only necessary to use decorative screws 15a or the like to keep the door closed. Also, when the circuit breakers 2 are being taken out or put in there is no need to open the intermediate level door, and therefore any chance of damage to the instruments when the circuit breakers 2 are being taken out or put in is reduced.

An electrical mounting block 16 for control circuit parts is formed inside the enclosure 1 facing the door 10; this mounting block 16 may be so constructed that it can be readily pulled out of the switchboard, as shown in Figure 4. If this is done, the mounting of parts such as fuse receptacles and knife switches does not have to be carried out inside the narrow enclosure, the block is assembled outside of the enclosure and then pushed into the enclosure, thereby simplifying manufacture.

As regards the door 10, the manner of operation of the "user" gives rise to changes in the manner in which the instruments are mounted. In Figure 5 the standardisation of this intermediate level door has been taken into consideration and an example is shown in which for instance electrical meters are not required. The unwanted openings 10a and 10b are simply and neatly blanked off on the front face of the door in a way which is useful in practice. For this purpose, indicator plates 17 and 18 on which a circuit diagram of the electrical apparatus by line connections as shown in Figure 6a and Figure 6b are employed; these are suitably used for each unwanted opening in the door and block the abovementioned openings 10a and 10b. It is extremely useful to show the circuit diagram simply by means of the abovementioned line connection indicator plates 17 and 18.Figure 7 shows another way of blocking these openings 10a and 10b; a container having the same diameter as an ammeter is mounted on the rear side of a blank plate 17. The container extends through the opening and the plate is secured to the front face. That is to say, 21 is a tube, 22 is a cover for the tube 21, and spare components such as a fuse 23, a lamp, 24, contact grease 25, an AMP terminal 26 and other similar components can be accommodated in this tube. This arrangement is still more useful if combined with the one shown in Figures 6 (a) and (b).

Figures 8 (a) and (b) show another embodiment of this invention; the control circuits of the circuit breakers 2 are connected by means of cables 27, and plugs 28 provided at the ends of these cables are releasably connected to the mounting block 16. In this case, when for instance the top level circuit breaker 2 is being removed, if the top level door 8 is opened then the intermediate level door 10 must also be opened at the same time, as shown in Figure 9, and when the bottom level circuit breaker 2 is being removed the bottom level and intermediate level doors 9 and 10 must be opened at the same time. As a means for making this possible, coupling means such as shown in Figure 10 a catch 29 and a permanent magnet 30 are secured to the top level door 8 (or the bottom level door 9), and this is attracted to the inside of the intermediate level door 10.

Because of this arrangement, the intermediate level door 10 follows any opening movement of the top level or bottom level door 8 or 9. Moreover, if necessary it is also possible to open only the door 10 by itself.

As described above, when the present invention is used standardisation of the top and bottom doors becomes possible and as regards inspection and operation, also, an enclosure can be obtained which is excellent from the point of view of human engineering, besides which the standardisation enables the wiring to be made in blocks and therefore there is the advantage that enclosed switch or control gear can be obtained of which the quality is stable and the price is low.

WHAT WE CLAIM IS:- 1. An enclosure for electrical apparatus comprising a box-like structure defining upper and lower chambers each capable of accommodating electrical apparatus, an end wall of the structure comprising separate upper, lower and intermediate level doors, the upper and lower doors providing access to the upper and lower chambers respectively and the intermediate level door being adapted to receive on its outside face electrical instruments, switches and the like associated with electrical apparatus accommodated in the upper and lower chambers.

2. An enclosure as claimed in claim 1 wherein the upper and lower doors are identical.

3. An enclosure as claimed in claim 1 or 2 wherein the intermediate level door can be opened or closed independently of the other doors and coupling means are provided between the intermediate level door and each of the upper and lower doors whereby movement of either the upper or lower door causes corresponding movement of the intermediate level door.

4. An enclosure as claimed in any preceding claim wherein the intermediate level door has openings formed therein for receiving said electrical instruments, switches and the like.

5. An enclosure as claimed in claim 4 including a plate for fitting on the outside face od the intermediate level door over an unwanted opening.

6. An enclosure as claimed in claim 5 wherein a circuit diagram of at least some of the apparatus contained within the enclosure is shown on said plate.

7. An enclosure as claimed in claim 5 wherein said plate supports a container adapted to fit into the unwanted opening, said container serving to carry spare parts and components.

8. An enclosure as claimed in any preceding claim wherein an electrical mounting block for connection to apparatus in the upper and lower chambers is mounted in the enclosure behind the intermediate level door.

9. An enclosure as claimed in claim 8 wherein said mounting block is displaceable into and out of the enclosure through said intermediate level door.

10. An enclosure for electrical apparatus substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (10)

**WARNING** start of CLMS field may overlap end of DESC **. abovementioned openings 10a and 10b. It is extremely useful to show the circuit diagram simply by means of the abovementioned line connection indicator plates 17 and 18. Figure 7 shows another way of blocking these openings 10a and 10b; a container having the same diameter as an ammeter is mounted on the rear side of a blank plate 17. The container extends through the opening and the plate is secured to the front face. That is to say, 21 is a tube, 22 is a cover for the tube 21, and spare components such as a fuse 23, a lamp, 24, contact grease 25, an AMP terminal 26 and other similar components can be accommodated in this tube. This arrangement is still more useful if combined with the one shown in Figures 6 (a) and (b). Figures 8 (a) and (b) show another embodiment of this invention; the control circuits of the circuit breakers 2 are connected by means of cables 27, and plugs 28 provided at the ends of these cables are releasably connected to the mounting block 16. In this case, when for instance the top level circuit breaker 2 is being removed, if the top level door 8 is opened then the intermediate level door 10 must also be opened at the same time, as shown in Figure 9, and when the bottom level circuit breaker 2 is being removed the bottom level and intermediate level doors 9 and 10 must be opened at the same time. As a means for making this possible, coupling means such as shown in Figure 10 a catch 29 and a permanent magnet 30 are secured to the top level door 8 (or the bottom level door 9), and this is attracted to the inside of the intermediate level door 10. Because of this arrangement, the intermediate level door 10 follows any opening movement of the top level or bottom level door 8 or 9. Moreover, if necessary it is also possible to open only the door 10 by itself. As described above, when the present invention is used standardisation of the top and bottom doors becomes possible and as regards inspection and operation, also, an enclosure can be obtained which is excellent from the point of view of human engineering, besides which the standardisation enables the wiring to be made in blocks and therefore there is the advantage that enclosed switch or control gear can be obtained of which the quality is stable and the price is low. WHAT WE CLAIM IS:-

1. An enclosure for electrical apparatus comprising a box-like structure defining upper and lower chambers each capable of accommodating electrical apparatus, an end wall of the structure comprising separate upper, lower and intermediate level doors, the upper and lower doors providing access to the upper and lower chambers respectively and the intermediate level door being adapted to receive on its outside face electrical instruments, switches and the like associated with electrical apparatus accommodated in the upper and lower chambers.

2. An enclosure as claimed in claim 1 wherein the upper and lower doors are identical.

3. An enclosure as claimed in claim 1 or 2 wherein the intermediate level door can be opened or closed independently of the other doors and coupling means are provided between the intermediate level door and each of the upper and lower doors whereby movement of either the upper or lower door causes corresponding movement of the intermediate level door.

4. An enclosure as claimed in any preceding claim wherein the intermediate level door has openings formed therein for receiving said electrical instruments, switches and the like.

5. An enclosure as claimed in claim 4 including a plate for fitting on the outside face od the intermediate level door over an unwanted opening.

6. An enclosure as claimed in claim 5 wherein a circuit diagram of at least some of the apparatus contained within the enclosure is shown on said plate.

7. An enclosure as claimed in claim 5 wherein said plate supports a container adapted to fit into the unwanted opening, said container serving to carry spare parts and components.

8. An enclosure as claimed in any preceding claim wherein an electrical mounting block for connection to apparatus in the upper and lower chambers is mounted in the enclosure behind the intermediate level door.

9. An enclosure as claimed in claim 8 wherein said mounting block is displaceable into and out of the enclosure through said intermediate level door.

10. An enclosure for electrical apparatus substantially as hereinbefore described with reference to the accompanying drawings.