FORM 2
THE PATENTS ACT, 1970 PROVISIONAL SPECIFICATION
(See Section 10)
ACCESSORY MOUNTING TO A SWITCHING DEVICE
Numbered as dated
INVENTORS:
a) CHANDRAKANT ANKUSH PATIL
APPLICANT:
M/s. LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No 278,
Mumbai, 400 001, Maharashtra,
INDIA

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
NATURE OF THE INVENTION

ACCESSORY MOUNTING TO A SWITCHING DEVICE
A) Technical field
[0001] The embodiments herein generally relates to the mounting of the actuating mechanism on the external adaptable switching accessory and more specifically mounting of an external actuating device on the electrical switching device for actuating it remotely or from handle that is external to the switching unit enclosure.
B) Background
[0002] These switching devices are used to protect electrical circuitry and equipment from damage due to abnormal condition, such as an overload condition or a relatively high level short circuit or fault condition.
[0003] Switching devices typically have two positions corresponding to status of separable contacts. For example, these positions would include an "ON" position, in which separable contacts are closed, an "OFF" position in which the contacts are open. In a few switching device there could be a third state which would include tripped position in which the contacts are tripped open. These switching devices are usually installed in an enclosure so as to have all the control and distribution network laid in form of metallic sheets and or cable
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wires inside and all operating means from outside so as to prevent access to high voltage and thus a potential hazard
[0004] One such switching device is a molded case circuit breaker which is generally used to provide overcorrect protection for various types of electrical equipment. However, in some applications, it is desirable to have accessories external to the circuit beaker enclosure for various other applications coupled with the parent application. Examples of external accessories may include Rotary extended mechanisms intended to operate the breaker from outside the enclosure improving the operator safety. One more example to such an external accessory could be an electrical operator intended to be attached to the switching device for remote operation.
[0005] In such applications, external operators are provided that are adapted to be mechanically coupled to the operating knob of the switching device. The external operator is, typically, a lever or handle or motor operated remote operating mechanism. These external operators has actuating mechanism comprising a knob holder to hold the switching unit knob and desired rotary or reciprocating motion is given to this knob holder through some mechanism. This knob holder carries the knob of the switching unit to the desired state (ON /OFF), thus switching unit can be operated externally or remotely. While mounting the actuating mechanism on the switching unit it is desirable that, the knob holder of the actuating mechanism should engage positively with knob of the switching unit. Non engagement could cause damage to switching unit knob, switching unit or to actuating mechanism itself. It is also desirable that
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actuating mechanism (hereafter termed as actuating device) should not be mountable in "ON" state of switching device (hereafter termed as switching unit), as it could be harmful to property or workmen working at the site.
[0006] While the conventional solutions are advantageous for their intended purposes, the existing state of the art generally does not provide an actuator device that can easily and rightly be assembled on the switching unit.
[0007] Hence, there is a need for an actuator device that can be more easily and righdy assembled on the switching unit. There is further need for actuation mechanism which can avert or prevent unintentional forced wrong mounting of the actuator device on the switching unit, when actuator device and switching unit are in non preferred combination of state.
C) Object of the invention
[0008] An object of the invention is to provide a system to mount actuating or operating device on switching unit only in preferred state of the switching unit.
[0009] Another object of the invention is to provide a system that avoids any intentional non-intended wrong mounting of the actuating device on the switching unit.
[0010] Yet another object of the invention is to provide a system and
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mechanism to prevent or avert workman/operator from mounting the actuating device on switching unit in ON state of the unit.
D) Summary
[0011] The embodiments herein provide a mounting of an external actuating device on the electrical switching device for actuating it remotely or from handle that is external to the switching unit enclosure. For operating device like Electrical operating mechanism, stored energy operator, it is necessary that mounting of these devices on switching units should be correct. Wrong mounting of these devices would result in non-functioning, damage or failure of switching unit, actuator. The embodiments provide system and method to prevent wrong mounting of the actuating device on the switching unit. The mechanism ensures mounting only in one preferred combination of states of switching unit and actuating device that is when actuating device and switching unit both are in "OFF" state.
[0012] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the
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spirit thereof, and the embodiments herein include all such modifications.
E) Brief description of the drawings
[0013] The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which:
[0014] FIG. 1 illustrates an actuating device;
[0015] FIG. 2 illustrates mounting of actuating device on the switching unit;
[0016] FIG. 3 illustrates the state when the actuating device is charged and switching unit in "OFF" state;
[0017] FIG. 4 illustrates the state when actuating device is discharged;
[0018] FIG. 5 illustrates the state when the actuating device is charged and switching unit in "ON" state;
[0019] FIG. 6 illustrates the state when the actuating device is charged and switching unit in "tripped" state;
[0020] FIG. 7 illustrates actuating device mounted on the switching device.
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F) Detailed description of the Invention:
[0021] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0022] FIG. 1 illustrates an actuating device. Actuating device comprises of a knob holder 2 which can reciprocate. This reciprocal motion is obtained through mechanism which is driven by motor or manually through handle. Knob holder 2 has a slot in it to hold knob 5 of switching unit 6. An interfering lever 3 coupled with torsional spring 4 is hinged to adaptor block 1 and retained with a circlip. Torsional spring 4 keeps lever 3 in outward position when it is not in contact with knob holder 2. Knob holder 2 has extended portion 2A and rib 2B.
[0023] FIG. 2 illustrates mounting of actuating device on the switching unit. When knob 5 of the switching device 6 is in "OFF" position, slot in knob holder 2 aligns with switching unit knob as actuating device is in charged state.
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After mounting actuating device on switching unit, it is tightened with screw 7 to switching unit. For mounting actuating device on switching unit, actuator device need to be in charged state. When actuating device is in discharged state, interfering lever come out of the adaptor block due to spring force. This averts mounting of actuating device on switching unit. While charging as knob holder moves, at one point when it approaches charged status, interfering lever rides on the rib 2B of knob holder and knob holder pushes it inward. So actuating device can be mounted easily on the switching unit. When actuating device mounted on the switching unit, as shown in FIG 2, only possible combination of state of actuating device and switching unit is, actuating device should in charged state and switching unit in "OFF" state. Charged state of the actuator corresponds to "OFF" state. Charged state refers to the state of the spring inside the mechanism, which stores and releases the energy.
[0024] FIG. 3 illustrates the state when the actuating device is charged and switching unit in "OFF" state. . In this combination of states, knob holder slot aligns with switching unit knob and knob holder engages with knob.
[0025] FIG. 4 illustrates the state when actuating device is discharged. When actuating device is in discharged state, the interfering lever due to torsional spring force comes out, which prevents the mounting of the actuator device on switching unit, irrespective of the state of the switching unit.
[0026] When the actuating device is in charged state and switching unit is in "ON" state or "TRIPPED" state as in FIG 5 and FIG 6, while mounting knob
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of switching unit interferes with extended knob holder portion, hence preventing it from mounting
[0027] FIG. 7 illustrates actuating device mounted on the switching device.
[0028] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
The detailed scope and monopoly of the invention shall be more clearly ascertained at the time of filing Complete Specification
Rakesh Prabhu,
Patent Agent,
Dated this the 28™ day of March, 2007

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ALMT Legal,
No.2, Lavelle Road, Bangalore-560 001, INDIA
To,
The Controller of Patents,
The Patent office,
At Mumbai

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Abstract
[0029] The embodiments herein provide a mounting of an external actuating device on the electrical switching device for actuating it remotely or from handle that is external to the switching unit enclosure. For operating device like Electrical operating mechanism, stored energy operator, it is necessary that mounting of these devices on switching device should be correct. Wrong mounting of these devices would result in non-functioning, damage or failure of switching unit, actuator. The embodiments provide system and method to prevent wrong mounting of the actuating device on the switching unit. The mechanism ensures mounting only in one preferred combination of states of switching unit and actuating device that is when actuating device and switching unit both are in "OFF" state.
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