GB2331401A

GB2331401A - Drive apparatus for switchgear

Info

Publication number: GB2331401A
Application number: GB9723841A
Authority: GB
Inventors: Alan Urmston
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-11-13
Filing date: 1997-11-13
Publication date: 1999-05-19
Also published as: GB9723841D0; GB2331401A9

Abstract

A drive apparatus 10 for operating switchgear 1 comprises a motor 13 which drives coupling means 14 from a remote power source 17, i.e. a vehicle battery. The motor is actuated by a remote actuation means 16 and such an arrangement improves operator safety by avoiding the risks from flash fires. The drive apparatus 10 may be temporarily installed on the switchgear cabinet 1 via a clamp arrangement 11.

Description

2331401 SWITCHGEAR DRIVE APPARATUS

The present invention relates in general to the field of electrical switcligear, and in particular, but not exclusively, to an apparatus for driving 5 electrical switcligear.

Electrical switcligear will be familiar to persons skilled in many areas of the electrical engineering industry and is commonly used for high voltage applications in the region of 1000W to 3300OW. These switcligear units are used, for example, to switch loads or to close down part of a network for repair or routine maintenance. Most commonly, the switcligear units are oil filled to inhibit arcing as contact is made or broken. Switching in prior art switcligear is performed manually by an operator moving an operating arrangement projecting through a housing of the switeligear to drive a switching arrangement which moves contacts within the housing to make or break a circuit. The operating arrangement typically comprises a lever or a boss for receiving a lever.

A problem arises in that the oil deteriorates over time and can fail to inhibit arcing. Other problems include water ingress into the switch gear cabinet, or mechanical failure of a switching component. In each case, a dangerous flash fire may be caused in and around the switcligear cabinet. Such flash fires are short-lived, but present a significant danger to an operator standing close to the cabinet to operate the drive lever. Such flash fires often result in significant burn injuries or even loss of life.

It is an aim of at least preferred embodiments of the present invention to improve operator safety when switching manually operated switcligear.

According to the present invention there is provide a drive apparatus for switchgear, comprising:

coupling means coupleable to an operating arrangement of a switchgear; motor means coupled to drive said coupling means; and remote actuation means for remotely actuating said motor means.

Preferably, said motor means is coupled to rotationally drive said coupling means about an axis of rotation co-axial to an axis of rotation of said operating arrangement. The drive apparatus preferably comprises gear means between said coupling means and said motor means, preferably for reducing rotational speed of said coupling means with respect to said motor means. For example, in the preferred embodiment a twelve gear reduction train is used to reduce rotational speed of the motor means from 400Orpm to 12rpm at the coupling means.

Preferably, the coupling means is readily releasably coupled to said operating arrangement, and preferably said drive apparatus is portable.

Ideally, the drive apparatus comprises a housing containing said motor means and coupling means, said housing being readily releasably coupleable to a housing of a switchgear, such that said coupling means is aligned with said drive lever.

Preferably, the remote actuation means switchably couples said motor means to a power source. Any suitable power source may be employed including, for example, a low voltage mains source such as 240 Vac; or conveniently a vehicle battery such as 12V or 24V DC. Preferably, the remote actuation means comprises switch means for actuating said motor means in a forward or a reverse direction. Other suitable remote actuation means may be employed including, for example, a non-wired system such as RF, infra-red, or other suitable signal.

The drive apparatus described herein has many advantages, principally that by providing a motor driven coupling for driving a manually operated drive lever, and remote actuation means, the operator may drive the switchgear from a safe remote location.

For a better understanding of the invention, and to show how emboditnents of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings, in which:

Figure 1 is a schematic side view of a preferred drive apparatus in use.

Referring to Figure 1, a preferred embodiment of the drive apparatus 10 is shown in use coupled to a switchgear cabinet 1. The cabinet 1 is suitably provided with an operating arrangement in the form of a dog 2 protruding through the cabinet 1. The dog 2 is keyed and intended to be connected to a correspondingly keyed operating handle (not shown). The handle is removed from the dog 2 when not in use to inhibit unauthorised switching, particularly where the cabinet is located in an urban area. The cabinet 1 contains the switching arrangement driven by rotation of dog 2 to make or break contacts. It will be appreciated that the operating arrangement may take any suitable form and may be provided at any convenient location on the cabinet 1.

The drive apparatus is preferably readily releasably coupled to the cabinet 1 such as by a clamping arrangement 11 arranged to conveniently clamp to, for example, a top cover 3 of the switching cabinet 1. As illustrated in Figure 1, the clamping arrangement 11 may conveniently comprise a bracket 111 and a clamp screw 112. However, other clamping arrangements will be apparent to the skilled person and other temporary attachment, such as by magnetic attraction, will be considered by the skilled person.

Conveniently, the clamping arrangement 11 is coupled to a housing 12.

The housing preferably contains a motor and a drive train arranged to impart a rotational drive to a coupling socket 14. The drive train may suitably comprise a gear reduction train to reduce the speed of the motor from, for example, 400Orpm to a speed such as around 12rpm, at the socket 14 consistent with the rotational speed expected of a manual operator. The preferred gear train comprises a multiple stage unit, and preferably a worm and wheel reducer.

The motor 13 is coupled such as by a lead 15 to a remote actuator 16.

The remote actuator 16 may conveniently be coupled to a suitable power source such as through the cigar lighter socket to a vehicle battery 17, or 240V ac mains power. The remote actuator 16 controls forward and reverse movement of the motor 13 to drive socket 14 in a desired direction. Limit means are provided either electrically or mechanically to limit the run of the motor 13 in either direction according to the known limits of movement of the drive dog 2 of the switchgear cabinet 1.

The drive apparatus described above has a number of advantages. The drive apparatus 10 may be fitted to a switcligear cabinet 1 whilst the switcligear is in a safe operative or inoperative position, and the operator may retire to a safe distance to remotely actuate the drive apparatus. Once the risk of flash fire has passed, the operator may then approach the switcligear cabinet to continue with the desired repair or maintenance task. The drive apparatus is readily removable and may travel with the operator from site to site. A significant cost saving is therefore made by avoiding the need to install an apparatus permanently on each switeligear cabinet. Further, little or no modification is required to the existing manually operated switcligear cabinet, thus avoiding modification costs. The drive apparatus is suitably coupled to a readily available power source such as a vehicle battery, for simplicity and economy.

The dimensions and arrangement of each drive apparatus is selected according to the desired switcligear cabinet and modifications beyond those shown in the drawings will be apparent to the skilled person.

Remote actuator 16 may be coupled to motor 13 by any suitable communication means replacing lead 15. In a development of the present invention, the drive apparatus is conveniently coupled to a switcligear cabinet 1 and may be operated by long distance remote control such as from a central control sensor. Advantages here may be seen where switching operations must be made repeatedly over a period of weeks or months in that the portable remotely actuated drive apparatus may be installed and left in position for that period of time. Further still, the drive apparatus may be permanently installed providing a remote actuation system with minimum modification to existing switcligear systems.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A drive apparatus for switcligear, comprising:

2. A drive apparatus as claimed in claim 1, wherein said couplings means is arranged to rotate about an axis of rotation coaxial with an axis of rotation of said operating arrangement.

3. A drive apparatus as claimed in claim 2, wherein said motor means is arranged to rotationaIly drive said coupling means about said axis of rotation.

4. A drive apparatus as claimed in any of claims 1 to 3, comprising gear means coupled between said coupling means and said motor means.

5. A drive apparatus as claimed in claim 4, wherein said gear means is arranged to reduce rotational speed of said coupling means with respect of said motor means.

6. A drive apparatus as claimed in any of claims 1 to 5, wherein said 25 coupling means is readily releasabIy coupleable to said operating arrangement.

7. drive apparatus as claimed in any of claims 1 to 6, being readily portabl when released from said operating arrangement.

8. A drive apparatus as claimed in any of claims 1 to 7, comprising a housing containing said motor means and said coupling means, said housing being readily releasably coupleable to a housing of a switchgear such that said coupling means is aligned with said operating arrangement.

9. A drive apparatus as claimed in claim 8, comprising a clamping arrangement for clamping said housing to said switchgear.

10. A drive apparatus as claimed in any of claims 1 to 9, wherein said remote actuation means switchably couples said motor means to a power source.

11. A drive apparatus as claimed in claim 10, wherein said remote actuation means comprises switch means for actuating said motor means in a forward or reverse direction.

12. A switchgear drive apparatus substantially as hereinbefore described with reference to the accompanying drawing.