FORM 2
THE PATENT ACT 1970
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION:
"Arrangement of a Compact Top Mounted Mechanism for Electrical Switching Device"
2. APPLICANT:
(a) NAME: Larsen & Toubro Limited
(b) NATIONALITY: Indian Company registered under the
provisions of the Companies Act-1956.
(c) ADDRESS: Larsen & Toubro Limited
L&T House, Ballard Estate,
P.O Box No. 278, Mumbai 400001, INDIA.
3. PREAMBLE TO THE DESCRIPTION:
COMPLETE
The following specification
particularly describes the invention and the manner in which it is to be performed.

Arrangement of a Compact Top Mounted Mechanism for Electrical Switching Device
Field of invention
The present invention relates to electrical switching devices, and more particularly to a top mounted rotary mechanism of low voltage switchgear devices.
Background of the invention
Electrical switching apparatuses, such as switch disconnectors, provide isolation of current in addition to making, carrying and breaking of the current for a specified time under various circuit conditions such as for example normal circuit conditions, specified operating overload conditions, specified abnormal circuit conditions such as short circuit and the like. These switch disconnectors are suitable in diverse applications in various electrical equipments, more specifically in motor control centers, switchboards, main switches and the like. However, these switches are ideal for withstanding higher short circuit current for short time duration.
Referring to FIGS. 1-2, the prior art electrical switches include a rotary mechanism that is operated from front, rear, left or right side, and is generally mounted on the side of contact system. In general, these electrical switches undergo to the OEM (Original Equipment Manufacturers), where the space is a major constraint. Hence, accommodation of these devices in optimum space is a major challenge. Also, these prior art mechanisms substantially increase the overall switch width of the mechanism if the mechanism is mounted on the left side or right side which is against the panel requirement design norms. For example, 1-pole represents 1-mode of 17.5mm pole width and if totally combined, a width all 4-poles itself becomes 70 mm. Accordingly, these mechanisms have a pole width of 17.5mm, a switch width 'W of 87.5mm, a height 'H' of 90mm and

a depth 'D' of 61mm in general. OEM would appreciate a rotary mechanism having switch width not exceeding beyond 70mm.
Additionally, the mechanisms of the prior art fail to fulfill the concept of manual independent operation. For example, these mechanisms are majorly operated by means of directly applied manual energy such that the speed and force of the operation are dependent upon the action of the operator. Hence, the operation of the electrical switches is majorly manual in the prior art devices.
Accordingly, there exists a need of a rotary mechanism that overcomes all the drawbacks of the prior art.
Objects of the invention
An object of the present invention is to provide a rotary mechanism having a compact size to be comfortably accommodated within a switch structure without increasing overall size of the switch.
Another object of the present invention is to provide the rotary mechanism having a manual independent continuous operation thereof.
Yet another object of the present invention is to provide the rotary mechanism facilitating delay in transmission operation thereof.
Still another object of the present invention is to provide the rotary mechanism having least number of components in transformation of the energy thereof.
Summary of the invention
Accordingly, the present invention provides a top mounted rotary mechanism supported on housing of a contact system of an electrical switch disconnector for

facilitating manual independent actuation thereof. The top mounted rotary mechanism comprises a rotor assembly having a moving contact, a contact system rotor, a magnetic cladding and a leaf spring. The top mounted rotary mechanism comprises a top plate and a bottom plate accommodating a first vertical rotor, a spring arm, a spring, a spring guide, a supporting pin and a driving pin therebetween. The first vertical rotor connects to the spring arm. The spring rests on the spring guide for connecting to the first vertical rotor thereto. The spring rests on the supporting pin. The spring guide positions on the first vertical rotor having the supporting pin supported thereon. The top mounted rotary mechanism comprises a slider-coupler arrangement that includes a first system coupler, a first slider, and a second slider. The first slider engages with the second slider through a driving pin. The first contact system coupler connects to the contact system Rotor. The first vertical rotor rotates to drive the first slider in a liner motion till a dead center position is achieved. The second slider drives the first contact system coupler thereby facilitating a rotation of the contact system rotor that turns ON the switch.
Brief description of the drawings
FIG. 1 shows a front view of a prior art 4-Pole switch disconnector having a modular contact system with a side mounted mechanism;
FIG. 2 shows a top view of the prior art 4-pole switch disconnector of FIG. 1;
FIG. 3 is a front view of a 4-Pole Switch Disconnector having a modular contact system with a top mounted rotary mechanism constructed in accordance of the present invention;
FIG. 4 is a top view of the 4-pole switch disconnector of FIG. 3;

FIG. 5 shows a general view of a preferred embodiment of the top mounted rotary mechanism of FIG. 3 in an OFF position;
FIG. 6 shows a general view of the preferred embodiment of the top mounted rotary mechanism of FIG. 5 in a dead centre position;
FIG. 7 shows a general view of the preferred embodiment of the top mounted rotary mechanism of FIG. 5 in an ON Position.
FIG. 8 shows a general side view of a contact system with the preferred embodiment of the top mounted rotary mechanism of FIG. 5 in an OFF Position;
FIG. 9 shows a general side view of the contact system of FIG. 8 with the top mounted rotary mechanism in a Dead Centre Position;
FIG. 10 shows a general side view of the contact system of FIG. 8 with the preferred embodiment of the top mounted rotary mechanism of FIG. 5 in an ON Position;
FIG. 11 shows a general view of a first contact system coupler of the preferred embodiment of the top mounted rotary mechanism of FIG. 5;
FIG. 12 shows a general view of a first slider of the preferred embodiment of the top mounted rotary mechanism of FIG. 5;
FIG. 13 shows a general view of a second slider of the preferred embodiment of the top mounted rotary mechanism of FIG. 5;
FIG. 14 shows a general view of an alternative embodiment of the top mounted rotary mechanism of FIG. 5;

FIG. 15 shows a general view of the alternative embodiment of the top mounted rotary mechanism of FIG. 14 in an OFF position;
FIG. 16 shows a general of the alternative embodiment of the top mounted rotary mechanism of FIG. 14 in a dead centre position;
FIG. 17 shows a general view of the alternative embodiment of the top mounted rotary mechanism of FIG. 14 in an ON Position.
FIG. 18 shows a general side view of a contact system with the alternative embodiment of the top mounted rotary mechanism of FIG. 14 in an OFF Position;
FIG. 19 shows a general side view of the contact system of FIG. 18 with the alternative embodiment of the top mounted rotary mechanism of FIG. 14 in a Dead Centre Position;
FIG. 20 shows a general side view of the contact system of FIG. 18 with the alternative embodiment of the top mounted rotary mechanism of FIG. 14 in an ON Position;
FIG. 21 shows a general view of a second contact system coupler of the alternative embodiment of the top mounted rotary mechanism of FIG. 14; and
FIG. 22 shows a general view of a third slider of the alternative embodiment of the top mounted rotary mechanism of FIG. 14.
Detailed description of the invention
The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are

overcome by the present invention as described below in the preferred embodiments.
Accordingly, the present invention provides a top mounted rotary mechanism that is mounted on top of a contact system thereby providing two different ways of achieving a manual independency. The rotary mechanism uses a unique slider-coupler arrangement wherein a slider and a coupler are arranged such that an electrical switch is effectively actuated thereby optimizing spring parameters without increasing overall size of the switch and without affecting the overall size of the rotary mechanism.
Referring to FIGS. 3-4, a top mounted rotary mechanism (1) adapted to be mounted atop a contact system (2) having four poles is shown. An overall switch width 'W1' of the contact system (2) is designed to be of 70 mm wherein a width of each pole is configured to be of 16.4 mm. In this one embodiment, an overall height 'H1' and a depth 'D1' of the contact system (2) are designed to be of 78 mm and 61 mm respectively.
Referring to FIGS. 5-13, a preferred embodiment of the rotary mechanism (1) configured to actuate the contact system (2) is shown. The contact system (2) includes a terminal (3) and a rotor assembly. The rotor assembly includes a moving contact (4), a rotor (5), a magnetic cladding (7) and a leaf spring (8). The rotary mechanism (1) is supported on a common contact system housing (9) (Refer FIG. 9).
The mechanism (1) includes a top cover (10), a side cover (11), a top plate (12), a bottom plate (13), a first vertical rotor (14), a spring arm (15), a spring (16), a spring guide (17), a supporting pin (18), and a driving pin (21). The mechanism (1) also includes a first system coupler (6), a first slider (19), and a second slider (20).

The mechanism (1) normally remains in an OFF position (as shown in FIG. 5). In this position, the spring (16) is in pre-charge condition. In this position, the first vertical rotor (14) couples with the spring arm (15), the spring (16) and the spring guide (17). The spring (16) rests on the spring guide (17) thereby directly connecting to the first vertical rotor (14). In this position, the spring (16) is having another end that rests on the supporting pin (18). The spring guide (17) is located on the first vertical rotor (14) and is supported by the supporting pin (18). This assembly is held in between the top plate (12) and the bottom plate (13). In this position, the first vertical rotor (14) and the first slider (19) are in different planes and are perpendicular to each other. However, the first slider (19) and the second slider (20) are in same plane in this position. The first vertical rotor (14) is adapted to drive the first slider (19) followed by the second slider (20). The second slider (20) drives the first contact system coupler (6) that is coupled with the contact System Rotor (5).
In operation, the mechanism (1) initially remains in the OFF position (as shown in FIG. 5 and FIG. 8). In order to turn ON the mechanism (1), an operator needs to operate the mechanism (1) till the dead centre, after which the mechanism spring (16) takes over to complete the switching operation. When the operator operates the switch, the first vertical rotor (14) rotates that in turn drives the first slider (19) linearly till the dead centre (as shown in FIG. 6 and FIG. 9). At this position, the first slider (19) temporarily engages with the second slider (20) using the driving pin (21). In this position, the second slider (20) directly drives the first contact system coupler (6) that in turn drives the contact system rotor (5) thereby turning the mechanism ON (as shown in figure 7 & 10). Accordingly, the manual independency is achieved by using this slider-coupler arrangement.
Referring to FIGS. 14-23, an alternative embodiment of the rotary mechanism (1) is shown. In this one alternative embodiment, the rotary mechanism (I) includes a top mechanism plate (12), a bottom mechanism plate (13), a second vertical rotor (23), a spring arm (15), a mechanism spring (16), a spring guide (17), a supporting

pin (18), a driving pin (21), a second contact system coupler (25) and a third slider (22). Initially, the mechanism (1) remains in an OFF condition wherein the mechanism spring (16) is in a pre-charge condition and the second vertical rotor (23) is coupled with the spring arm (15), the mechanism spring (16), and the spring guide (17). The mechanism spring (16) rests on the spring guide (17) to directly connect to the second vertical rotor (23). The mechanism spring (16) rests on the supporting pin (18) in this alternative embodiment. The spring guide (17) positions on the second vertical rotor (23) and is preferably supported by the supporting pin (18). In this alternative embodiment, the entire assembly is held between top mechanism plate (12) and the bottom mechanism plate (13). The second vertical rotor (23) and the third slider (22) preferably position along substantially different planes that are perpendicular to each other. The third slider (22) is adapted to drive the second contact system coupler (25) and is preferably coupled with the contact system rotor (5). The second vertical rotor (23) and the third slider (22) are arranged in substantially different planes that are perpendicular to each other. The second vertical rotor (23) is adapted to drive the third slider (22) such that the third slider (22) in turn drives the second contact system Coupler (25) that is coupled with the contact system rotor (5). It is understood here that the first slider (19) and the second slider (20) (as shown in FIG. 12 and FIG. 13 respectively) are integrated into the third slider (22) in this alternative embodiment thereby having two different gear profiles on the third slider (22) (as shown in FIG. 22).
In operation, the rotary mechanism (1) initially remains in an OFF position (as shown in FIG. 15 and FIG. 18). An operator need to operate the mechanism (1) till a dead centre to turn ON the switch, followed by which the mechanism spring (16) operates to complete the switching operation. When the operator operates the rotary mechanism (1), the second vertical rotor (23) rotates to drive an upper gear profile of the third slider (22) in a liner motion till the dead centre (as shown in FIG. 16 and FIG. 19). Subsequently, a lower gear profile of the third slider (22) drives the second contact system coupler (25). In operation, the second system

coupler (25) freely rotates till the dead centre and subsequently engages with the contact system rotor (5) to turn ON the switch (as shown in FIG. 17 and FIG. 20). Accordingly, the manual independency is achieved through the contact system coupler (25) and the contact system rotor (5) in this one alternative embodiment. In this alternative embodiment, the use of the third slider (22) reduces the size of the gear profile thereby maintaining a desired design angle and accommodating with in dimensions of the switch. The rotary mechanism (1) also achieves an intentional transmission delay by means of Coupler in this one alternative embodiment.
Advantages of the present invention:
1. The unique slider-coupler arrangement of the present invention is adapted in the rotary mechanism (1) optimizes size of the switch in addition to effectively actuating the switch without increasing the overall size of the switch.
2. The gear profiles of the vertical rotor (14), sliders (19), (20), (22) and couplers (6), (25) have been designed, such that the spring parameters can are optimized without affecting the overall size of mechanism (1)
3. The desired variable transmission delay is achieved by means of the slider-coupler arrangement by varying the engagement slot length in the first sliders (19) and the second slider (20). Alternatively, the desired variable transmission delay also can be achieved by varying the angular play in the third Coupler (25).
4. The slider coupler advantageously facilitates manual independency wherein the operator need to operate the switch only till the dead centre, after which the mechanism spring operates to actuate the switch fully through the vertical gear, the sliders and the coupler.
5. The mechanism (1) advantageously allows transformation of the energy from a vertical motion to a horizontal motion using least number of components.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching.
The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

We Claim:
1. A top mounted rotary mechanism supported on housing of a contact system
of an electrical switch disconnector for facilitating manual independent actuation
thereof, the top mounted rotary mechanism comprising:
a rotor assembly having a moving contact (4), a contact system rotor (5), a magnetic cladding (7) and a leaf spring (8);
a top plate (12) and a bottom plate (13), the top plate and the bottom plate accommodating a first vertical rotor (14), a spring arm (15), a spring (16), a spring guide (17), a supporting pin (18), and a driving pin (21) therebetween, the first vertical rotor (14) connecting to the spring arm (15), the spring (16) resting on the spring guide (17) for connecting to the first vertical rotor (14) thereto, the spring (16) resting on the supporting pin (18), the spring guide (17) positioning on the first vertical rotor (14) having the supporting pin (18) supported thereon; and
a slider-coupler arrangement including a first system coupler (6), a first slider (19), and a second slider (20), the first slider (19) engaging with the second slider (20) through a driving pin (21), the first contact system coupler (6) connecting to the contact system Rotor (5), the first vertical rotor (14) rotating to drive the first slider (19) in a liner motion till a dead center position thereof, the second slider (20) driving the first contact system coupler (6) thereby facilitating a rotation of the contact system rotor.
2. The top mounted rotary mechanism as claimed in claim 1, wherein the first slider (19) positions in a plane that is substantially perpendicular to a plane of the first vertical rotor (14)
3. The top mounted rotary mechanism as claimed in claim 1, wherein the first slider (19) and the second slider (20) are positioned along a common plane.

4. The top mounted rotary mechanism as claimed in claim 1, wherein the slider-coupler arrangement actuates the top mounted rotary mechanism by facilitating a manual independency in operation thereof.
5. The top mounted rotary mechanism as claimed in claim 1, wherein the first slider (19) and the second slider (20) are integrally connectable to form a third slider having gear profiles of both the first slider (19) and the second slider (20) defined thereon.
6. The top mounted rotary mechanism as claimed in claim 1, wherein the slider-coupler arrangement reduces gear profile size provides an intentional variable transmission delay.
7. The top mounted rotary mechanism as claimed in claim 1, wherein the slider-coupler arrangement facilitates a size optimization without increasing the overall size thereof.