High-voltage switches with arc preventing or extinguishing devic – Arc preventing or extinguishing devices – Polyphase
Reexamination Certificate
2000-03-31
2001-07-31
Donovan, Lincoln (Department: 2832)
High-voltage switches with arc preventing or extinguishing devic
Arc preventing or extinguishing devices
Polyphase
C218S120000
Reexamination Certificate
active
06268579
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a vacuum switch gear and a vacuum switch gear unit capable of easily connecting an integrated container in which a grounded vacuum container or a vacuum container and a gas-insulated ground container are utilized in combination, to buses, and a vacuum switch gear system wherein the units are connected to one another.
BACKGROUND ART
With an increase demand for power consumption centralized areas in cities, the attainment of a rise in distribution voltage, i.e., positive load absorption into a 22KV system large in capacity per line, rather than a 6KV one due to a difficulty in the siting of a 6KV supply-based distributing substation, no allowance for the placement of distributing piping and an increase in availability factor of a 6KV supply installation, etc., leads to the formation of an efficient power supply installation. It is therefore necessary to bring 22KV distribution equipment into compact form like compact 7KV to 6KV equipment.
An SF
6
gas-insulated switch gear described in, for example, Japanese Patent Laid-Open No. Hei 3-273804 is considered as power receiving and transforming equipment to, be brought into compact form. In this type of switch gear, a unit room or chamber charged with an insulation gas is fabricated and held in a distribution box, and a breaker, two disconnectors and a ground switch are individually manufactured and accommodated in bus rooms or chambers. When a vacuum breaker is used as the breaker, a movable electrode is moved upward and downward with respect to a fixed electrode by an operation unit of the vacuum breaker to thereby perform throwing and cutting-off. According to a vacuum breaker described in Japanese Patent Laid-Open No. Sho 55-143727 as an alternative to above, a movable electrode is turned vertically or horizontally with a main shaft as the fulcrum so as to be connected to or disconnected from a fixed electrode, whereby throwing and cutting-off are carried out.
The gas-insulated switch gear receives power supplied from, for example, an electric power company through a disconnector and a gas breaker or the like, transforms it into the optimum voltage for a load by a transformer and supplies power to a load, e.g., a motor or the like. The power receiving and transforming equipment is maintained and checked as follows. After a gas breaker has been cut off, a disconnector provided separately from the gas breaker is rendered open and a ground switch is further grounded to thereby allow the residual charge on the source side and induced current to flow into ground. Thus, the re-application of the voltage from the source is prevented to keep the safety of a worker. Grounding the ground switch while a bus remains charged leads to an accident. Therefore, an interlock is provided between the disconnector and the ground switch.
In SF
6
gas-insulated switching equipment described in, for example, Japanese Patent Laid-Open No. Hei 3-273804, a unit room or chamber charged with an SF
6
gas is fabricated and held in a distribution box, and a gas breaker, two disconnectors and a ground switch are individually manufactured and accommodated in bus rooms or chambers respectively. When a vacuum breaker is used as the breaker, a movable electrode lying within a vacuum container is moved upward and downward with respect to a fixed electrode by an operation unit to thereby perform throwing and cutting-off. According to a vacuum breaker described in Japanese Patent Laid-Open No. Sho 55-143727 as an alternative to above, a movable lead corresponding to a movable blade and a movable electrode lying within a vacuum container are turned from side to side with a main shaft as the fulcrum so as to be connected to or disconnected from a fixed electrode, whereby throwing and cutting-off are carried out. Further, a rod extends outside a vacuum container described in Japanese Patent Laid-Open No. Sho 59-75527 from the back of each of a movable electrode and a fixed electrode lying within the vacuum container. However, any of these publications does not take into consideration a portion for connecting a source-side conductor and a source bus. While a vacuum switch gear enclosed in a gasinsulated container has been described in Japanese Patent Laid-Open No. Hei 9-153320, it does not take into consideration a portion for connecting a source-side conductor and a source bus in a manner similar to the above.
An object of the present invention is to provide a vacuum switch gear capable of easily performing a connection between a bus or source-side bus and a grounded vacuum container or integrated container, a vacuum switch gear wherein a plurality of vacuum switches are provided in cooperation with one another, a vacuum switch gear unit, and a vacuum switch gear system. In the present invention, a vacuum container may be grounded. Alternatively, the vacuum container may be one placed within a gas-insulated container which is grounded.
DISCLOSURE OF INVENTION
The present invention provides a vacuum switch gear comprising (1) a vacuum switch having a vacuum container, a fixed electrode connected to within the vacuum container, a movable electrode connected to or disconnected from the fixed electrode, a load conductor electrically connected to the movable electrode, and an external conductor electrically connected to the fixed electrode, (2) an operation mechanism unit for driving the movable electrode, and (3) buses each electrically connected to the external conductor, and also provides a vacuum switch gear unit wherein a plurality of the vacuum switch gears each referred to above are brought into unit form. Further, the vacuum switch gears brought into unit form are connected to other units through buses, thereby making it possible to constitute an intended vacuum switch gear system. In the present invention, a connecting portion for connecting the external conductor extending from the vacuum container and each bus is one wherein the buses extending in a direction horizontal to the longitudinal axis of the external conductor and a connecting end of the external conductor are surrounded by interface insulation. While an interface insulating method has already been known as a connecting method such as a cable head or the like, the present invention makes use of this interface connection to ensure the connection between the vacuum switch and each bus. The interface connection is a connecting method of forcibly press-fitting an elastic body such as rubber between a hard solid insulator such as ceramics, a resin or the like and a wall (or container wall) for surrounding a connecting portion and firmly closely-fitting an interface between the fixed insulator and the elastic body to thereby increase withstand pressure. As an independent improvement in elastic body according to the present invention, the connecting portion is provided with a press-fit operation unit to press-fit the elastic body from the outside of the connecting portion. A greater advantage of the present invention resides in that the grounded vacuum container and the connecting structure can be rendered substantially identical to each other in structure. Thus, a vacuum switch, an operation-mechanism, a controller, a connecting portion and buses are respectively prepared in plural sets. They can be easily assembled so as to constitute an intended circuit or line. Consequently, the vacuum switch gear, the vacuum switch gear unit and the vacuum switch gear system can be reduced in manufacturing cost.
In the present invention, butt ends of a pair of bus conductors extending in a direction orthogonal to a longitudinal direction of superimposed external conductors or in their transverse direction are superimposed on each other as connecting pieces at an end of the superimposed external conductors. A fastening or tightening device such as a bolt is inserted into a through hole defined in the superimposed portion. The fastening device is tightened by a nut or the like so as to fix between the connecting pieces. A solid insulator of a connecting structure of a bus emp
Kajiwara Satoru
Morita Ayumu
Shibata Yozo
Tanimizu Toru
Watanabe Yoshiyasu
Donovan Lincoln
Hitachi , Ltd.
Mattingly Stanger & Malur, P.C.
LandOfFree
Vacuum switchgear does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vacuum switchgear, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vacuum switchgear will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2561702