FORM 2
The Patents Act 1970
(39 of 1970)
&
The Patent Rules 2003
COMPLETE SPECIFICATION
(See Section 10 and rule 13) TITLE OF THE INVENTION:
SINGLE KNOB ARRANGEMENT FOR MULTIPOLES IN
MODULAR DEVICES
APPLICANT:
LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No. 278,
Mumbai, 400 001, Maharashtra . INDIA.
PREAMBLE OF THE DESCRIPTION:
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

A) TECHNICAL FIELD
[0001] The present invention generally relates to switching devices such as miniature circuit breaker, residual current circuit breaker and isolator etc., and particularly to operating knob arrangement for multi-pole circuit breakers. The present invention more particularly relates to a single operating knob mechanism to connect and drive the knobs coupled to multiple poles together in a multi-pole circuit breaker.
B) BACKGROUND OF THE INVENTION
[0002] Switching devices such as miniature circuit breaker, residual current circuit breaker, isolators and like are generally used to provide protection against over current, under current supply and or earth leakages to the end product. The circuit breaker normally serves the dual function of opening and closing a circuit. Where the circuit breaker consists of two or more poles, it is desirable to open or close all poles of the breaker at the same time during overload or short circuit conditions. To accomplish this, there have been arrangements in which the operating handles for each pole have been mechanically tied together externally so that operation of one handle would operate all handles.
[0003] Each single pole circuit breakers includes an ON and OFF operating handle protruding from the circuit breaker case. The handle controls the operating mechanism disposed within the circuit breaker enclosure. The ON position indicates that the circuit is

closed, or in operation, while the OFF position indicates that circuit is open, or disengaged. A multi-pole circuit breaker is defined as a modular array of single pole circuit breakers connected together. The Multi-pole circuit breakers require that all operating handles be set to their ON and OFF position in unison. Each pole of multi-pole circuit breakers typically includes a trip unit that senses the current flowing through a given point of a conductor of the pole. Such multi-pole circuit breakers additionally include a single operating mechanism that is common to all of the poles and that is operative to separate the sets of separable contacts of the poles. Any of the trip units of the circuit breaker can trigger the operating mechanism to interrupt current flowing through all of the poles when the trip unit detects an over current or under voltage condition or other condition that warrants a trip operation.
[0004] Currently, a number of methods exist for connecting the multi-pole circuit breakers. The presently available method for connecting and driving multi-pole circuit breakers is complex. In any kind of circuit breaker or switching device, there exists a problem as how to connect the multiple knobs together easily and effectively. Hence there is a need to provide a mechanism to connect and drive the multiple knobs together in a multi-pole circuit breaker easily with a simple design. Also there is a need to provide a single main knob to govern the entire switching mechanism of the multi-pole circuit breakers.
C) OBJECTS OF THE INVENTION

[0005] The primary object of the present invention is to provide an operating knob with a unique mechanism to connect and drive multiple knobs together in multi-pole circuit breaker.
[0006] Another object of the present invention is to provide a multi-pole circuit breaker with an operating knob which is compact and used for connecting double pole, three pole, four pole, single pole with neutral protection and three poles with neutral protection.
[0007] Yet another object of the present is to provide a main knob for governing the entire switching mechanism consisting of multiple knobs in a multi-pole circuit breaker.
[0008] Yet another object of the present invention is to provide a unique design for the enclosure of housing and cover in a multi-pole circuit breaker.
[0009] Yet another object of the present invention is to provide a circuit breaker or modular devices with a single knob to govern the entire mechanism consisting of any number of modules.
[0010] These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.

D) SUMMARY OF THE INVENTION
[0011] The various embodiments of the present invention provide a unique mechanism for connecting multiple knobs together in a multi-pole circuit breaker assembly and to govern the entire circuit breaker device consisting of pluralities of modules. According to one embodiment of the present invention, a single knob arrangement for multipoles in circuit breaker device has pluralities of main pole knobs connected respectively to the pluralities of poles in the circuit breaker device. A left side knob is connected to one main pole knob and a right side knob is connected to one main pole knob. Each main pole knob has a projection at one end and a recess at another end sothat the projection provided in one main pole knob is received into the recess provided in the adjacent main pole knob to operate the pluralities of knobs with a single operation.
[0012] The projection in each knob is protruded from one side of the each knob. The recess in each main pole knob is provided at a side surface which is opposite to the side surface provided with the projection. An operating handle is attached to the main pole knobs so that the operating handle of all the main pole knobs are aligned together to operate all the main pole knobs with a single operation, when all the main pole knobs are connected together.
[0013] The left side knob is provided at the extreme left end and connected to the main pole knob provided at the extreme left end. The left side knob has a recess at the right side surface. The right side knob is provided at the extreme right end and connected

to the main pole knob provided at the extreme right end. The right side knob has a projection formed at the left side surface. The total number of main pole knobs, the left side knob and the right side knob correspond to the total number of poles provided in the circuit breaker device.
[0014] The various embodiments of the present invention provide a unique mechanism for connecting multiple knobs together in a multi-pole circuit breaker assembly. The multiple knobs are connected to main knob which governs the entire circuit breaker switching mechanism. According to one embodiment, an operating knob of each single-pole circuit breaker comprises of a horizontal protrusion towards one end and a hole towards other end. The protrusion and the dimple on each knob are provided to interconnect multiple knobs to gather in the multi-pole circuit breaker.
[0015] The multi-pole circuit breaker assembly is enclosed inside the circuit breaker housing with cover. A unique front cover with a click-fit arrangement with the circuit breaker housing is provided to enclose the knob arrangement in the multi-pole circuit breaker.
[0016] According to one embodiment of the present invention, the multi-pole circuit breaker arrangement comprises of main pole knobs and side pole knobs connected together through the horizontal protrusion and the dimple on each operating knob. A typical four-pole circuit breaker arrangement includes two main knobs, one left side knob and one right side knob. The main knob is connected to left side and right side knobs by a protrusion in one end and the dimple in the other end. Whereas, in case of three-pole

circuit breaker the arrangement is to use one left side knob, one main knob and one right side knob. In same manner for two-pole arrangement the sequence is to use only two main knobs.
[0017] Hence the present invention provides a unique mechanism for connecting multiple knobs in a multi-pole circuit breaker assembly. The main knob drives the multiple knobs controlling the entire switching mechanism of multi-pole circuit breakers. The assembly is compact and can be used for Double Pole (DP), Three Pole (TP), Four Pole (FP), Single Pole with Neutral Protection (SPN) and Three Pole with Neutral Protection (TPN).
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:
[0019] FIG. 1 shows a perspective view of a typical four-pole circuit breaker provided with a single knob arrangement for multiple poles according to one embodiment of the present invention.

[0020] FIG. 2 shows a perspective view of a single knob arrangement for multiple poles for interconnecting the switching device knobs according to one embodiment of the present invention.
[0021] FIG. 3 shows an exploded perspective view of a single knob arrangement for multiple poles for interconnecting the switching device knobs according to one embodiment of the present invention.
[0022] FIG. 4 shows circuit breaker assembly provided with a single knob arrangement for multiple poles and without top cover in switched ON condition, according to one embodiment of the present invention.
[0023] Although the specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.
F) DETAILED DESCRIPTION OF THE INVENTION
[0024] In the following detailed description, a reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without

departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[0025] The various embodiments of the present invention provide a unique mechanism for connecting multiple knobs together in a multi-pole circuit breaker assembly and to govern the entire circuit breaker device consisting of pluralities of modules. According to one embodiment of the present invention, a single knob arrangement for multipoles in circuit breaker device has pluralities of main pole knobs connected respectively to the pluralities of poles in the circuit breaker device. A left side knob is connected to one main pole knob and a right side knob is connected to one main pole knob. Each main pole knob has a projection at one end and a recess at another end sothat the projection provided in one main pole knob is received into the recess provided in the adjacent main pole knob to operate the pluralities of knobs with a single operation.
[0026] The projection in each knob is protruded from one side of the each knob. The recess in each main pole knob is provided at a side surface which is opposite to the side surface provided with the projection. An operating handle is attached to the main pole knobs so that the operating handle of all the main pole knobs are aligned together to operate all the main pole knobs with a single operation, when all the main pole knobs are connected together.
[0027] The left side knob is provided at the extreme left end and connected to the main pole knob provided at the extreme left end. The left side knob has a recess at the right side surface. The right side knob is provided at the extreme right end and connected

to the main pole knob provided at the extreme right end. The right side knob has a projection formed at the left side surface. The total number of main pole knobs, the left side knob and the right side knob correspond to the total number of poles provided in the circuit breaker device.
[0028] The various embodiments of the present invention provide a unique mechanism for connecting multiple knobs together in a multi-pole circuit breaker assembly. The multiple knobs are connected to main knob to govern the entire circuit breaker switching mechanism. According to one embodiment, an operating knob of each single-pole circuit breaker comprises of a horizontal protrusion towards one end and a hole towards other end. The protrusion and the dimple on each knob help to interconnect multiple knobs to gather in a multi-pole circuit breaker.
[0029] The multi-pole circuit breaker assembly is enclosed inside the circuit breaker housing with cover. A unique front cover with a click-fit arrangement with the housing is provided enclose the knob arrangement in the multi-pole circuit breaker. According to one embodiment of the present invention, the multi-pole circuit breaker arrangement comprises of main pole knobs and side pole knobs connected together through the horizontal protrusion and the dimple on each operating knob. A typical four-pole circuit breaker arrangement includes two main knobs, one left side knob and one right side knob. The main knob is connected to the left and right side knobs. Whereas, in case of three-pole circuit breaker the arrangement is to use one left side, one main knob and one right side knob. In same manner for two-pole arrangement the sequence is to use only two main knobs.

[0030] Hence the present invention provides a unique mechanism for connecting multiple knobs in a multi-pole circuit breaker assembly. The main knob drives the multiple knobs controlling the entire switching mechanism of multi-pole circuit breakers. The assembly is compact and can be used for Double Pole (DP), Three Pole (TP), Four Pole (FP), Single Pole with Neutral Protection (SPN) and Three Pole with Neutral Protection (TPN).
[0031] FIG. 1 shows a perspective view of a typical four-pole circuit breaker in ON position according to one embodiment of the present invention. Referring to FIG.l, the four-poles are enclosed in circuit breaker housing 104. The knob of a single-pole circuit breaker includes a protrusion in one end and the dimple in other end. All the knobs of four poles are interconnected through a protrusion and dimple arrangement. The four-pole arrangement includes two main knobs 101 and 102, one left side knob and one right side knob. The main pole knobs 101 and 102 are connected to the left side knob and right side knob.
[0032] FIG. 1 shows two main knobs in ON position and is accessible from outside. As all the knobs of four poles are interconnected, when the main pole knobs 101 and 102 is turned ON, all the four-pole circuit breakers will be switched ON. Whenever there is an overload or short circuit condition, all the circuit breaker trips simultaneously disconnecting the circuit. The circuit breaker enclosure is overall closed on the front face

by a unique front cover 103. The front cover 103 is click fitted with the circuit breaker housing 104 and cover 105. The front cover 103 is provided to cover the knob arrangement thereby providing access only to the main knobs. Thus the main knob independently drives the entire mechanism consisting of four-poles. The mechanism is also used for two pole variants to any number of poles. For two-poles the sequence is to use two main knobs 101 and 102, where as in case of three-poles the sequence is to use one left side knob, one main knob, and one right side knob.
[0033] FIG. 2 and FIG.3 show respectively a perspective view and an exploded view of the interconnection between the switching device knobs in a four-pole circuit breaker, according to one embodiment of the present invention. Referring to FIG. 3, the main knobs 101 and 102 are connected to left side knob 201 and right side knob 202 by a protrusion 301 in one end and the dimple 302 in the other end. The main pole knobs 101 and 102 are connected to the left side knob 201 and right side knob 202 by a unique arrangement. The present arrangement is used for two pole variants to any number of poles.
[0034] FIG. 4 shows circuit breaker assembly without top cover in ON Position, according to one embodiment of the present invention. Referring to FIG.4, the four-poles are enclosed in circuit breaker housing 104. The knob of a single-pole circuit breaker includes a protrusion in one end and the dimple in other end. All the knobs of four poles are interconnected through a protrusion and dimple arrangement. The four-pole arrangement includes two main knobs 101 and 102, one left side knob 201 and one right

side knob 202. The main pole knobs 101 and 102 are connected to the left side knob 20land right side knob 202.
G) ADVANTAGES OF THE INVENTION
[0035] Thus the various embodiments of the present invention provide a unique mechanism to connect and drive multiple knobs to gather in a multi-pole circuit breaker assembly. The multiple knobs are connected to the single main knob to govern the entire circuit breaker switching mechanism in a multi-pole circuit breaker. The assembly is compact and used for Double Pole (DP), Three Pole (TP), Four Pole (FP), Single Pole with Neutral Protection (SPN) and Three Pole with Neutral Protection (TPN). Only one knob will govern the entire mechanism consisting of any number of modules. It provides a unique front cover with a click fit arrangement for multi-pole circuit breaker housing with cover.
[0036] Although the invention is described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims. [0037] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the present invention described herein and all the statements of the scope of the invention which as a matter fall there between.

CLAIMS
What is claimed is:
1. A single knob arrangement for multipoles in circuit breaker device including
pluralities of poles comprising:
Pluralities of main pole knobs connected respectively to the pluralities of poles in
the circuit breaker device;
A left side knob connected to one main pole knob; and
A right side knob connected to one main pole knob;
Wherein each main pole knob has a projection at one end and a recess at another
end sothat the projection provided in one main pole knob is received into the
recess provided in the adjacent main pole knob to operate the pluralities of knobs
with a single operation.
2. The arrangement according to claim 1, wherein the projection in each knob is protruded from one side of the each knob.
3. The arrangement according to claim 1, wherein the recess in each main pole knob is provided at a side surface which is opposite to the side surface provided with the projection.
4. The arrangement according to claim 1, wherein an operating handle is attached to the main pole knobs so that the operating handle of all the main pole knobs are aligned together to operate the all the main pole knobs with a single operation, when all the main pole knobs are connected together.
5. The arrangement according to claim 1, wherein the left side knob is provided at the extreme left end and connected to the main pole knob provided at the extreme left end.

6. The arrangement according to claim 1, wherein the left side knob has a recess at the right side surface.
7. The arrangement according to claim 1, wherein the right side knob is provided at the extreme right end and connected to the main pole knob provided at the extreme right end.
8. The arrangement according to claim 1, wherein the right side knob has a projection formed at the left side surface.
9. The arrangement according to claim 1, wherein the total number of main pole knobs, the left side knob and the right side knob correspond to the total number of poles provided in the circuit breaker device.