FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention- COMMON AMPLIFICATION MECHANISM FOR
UNDER-VOLTAGE RELEASE & SHUNT RELEASE
2. Applicant(s)
(a) NAME : Larsen & Toubro Limited
(b) NATIONALITY : An Indian Company
(c) ADDRESS: L&T House, Ballard Estate, Mumbai-400 001,
Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

TECHNICAL FIELD OF THE INVENTION
The present invention relates generally for switchgear applications. Particularly, the present invention relates to a Moulded case circuit breaker & Circuit breakers where internal accessories like UV & shunt release are used. More particularly, the invention relates to a mechanism where amplification of smaller force to higher value is required and communization of majority of components is required.
BACKGROUND AND PRIOR ART OF THE INVENTION
An under-voltage (UV) release is used in circuit breaker to offer protection against under voltage
or zero voltage condition. Under voltage release trips the circuit breaker mechanism when the
voltage across the terminals of the release falls below a predetermined value; hence it goes
along with the circuit breaker module as internal accessories. Shunt release is used for
electrical tripping of the circuit breaker by a control supply voltage, mainly for remote tripping.
Both UV and shunt release uses electromagnetic coil to provide the trip signal. The
electromagnetic coil size required to generate required trip force will be larger. Considering
space constrains, electromagnetic coil will be designed for smaller force and this force will be
amplified to a higher value so as to trip the Circuit breaker mechanism. Hence both UV & shunt
release uses an amplification mechanism along with the electromagnet to trip the circuit
breaker.
* In UV release the output from the electromagnet section will produce a force that can rotate the
latch in clockwise direction and in shunt release the electromagnet section will produce a force
that can rotate the latch in counter clockwise direction.
The present inventors have found that in the present invention, the same compact mechanism that can amplify and transfers the force provided by the electromagnet to trip the circuit breaker has been modified such a way that by modifying the profile of one component can accommodate the usage of this mechanism in both UV and Shunt release.

OBJECTS OF THE INVENTION
One object of the present invention is to overcome the disadvantages / drawbacks of the prior art.
A basic object of the present invention is to provide a mechanism that protect the appliance from under-voltage condition there is a requirement for circuit breaker to sense the under-voltage condition and trip the circuit breaker. For having remote tripping facility a shunt trip unit is required
Another object of the present invention is to provide a mechanism that minimizes number of component, thus effectively utilizes the compact mechanism designed.
Yet another object of the present invention is to provide a mechanism where amplification of smaller force to higher value is required and communization of majority of components is
required.
These and other advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.
According to one of the aspect of the present invention the system is provided a Common Amplification mechanism for Under-Voltage Release & Shunt Release, said mechanism comprising:
a side plate;

plurality of pins mounted on said side plate, said plurality of pins comprises latch pin, spring pin and actuator pin;
a actuator means mounted on said actuator pin and said actuators other end carries latch pin;
a main spring connected between said spring pin and actuator adapted to rotate actuator in anticlockwise direction; and
a latch mounted on said spring pin and its rotation is controlled by a bias spring such that said latches profile is changed adapted to enable interchangeability between under voltage(UV) release and shut release;
such said latch comprises of UV latch and shunt latch , said UV latch assembled in said mechanism during UV release and said shunt latch assembled during shunt release.
Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to Common Amplification mechanism for Under-Voltage (UV) Release & Shunt Release.
The force required for tripping the circuit breaker will be larger. Designing an electromagnetic coil for higher force will make the coil size big. Hence an amplification mechanism is required for both UV release and Shunt release. Instead of designing separate amplification mechanism for UV release and shunt release. Amplification mechanism has been designed for UV release and with minimum single component modification it has been modified to suit shunt release, such that electromagnetic coil force in UV & Shunt release has been amplified to the sufficient higher force as required by the breaker mechanism.
This minimized number of components, thus effectively utilizes the compact mechanism designed.
According to one of the embodiments of the present invention there is provided a Common Amplification mechanism for Under-Voltage Release & Shunt Release. The mechanism

comprising a side plate; plurality of pins mounted on the side plate; a actuator means mounted on the actuator pin and the actuators other end carries latch pin; a main spring connected between the spring pin and actuator adapted to rotate actuator in anticlockwise direction; and a latch mounted on the spring pin and its rotation is controlled by a bias spring such that the latches profile is changed adapted to enable interchangeability between under voltage(UV) release and shut release.
The plurality of pins comprises latch pin, spring pin and actuator pin.
The latch comprises of UV latch and shunt latch, the UV latch assembled in the mechanism during UV release and the shunt latch assembled during shunt release.
The latch pin travelling is limited inside the slot off side plate.
The actuator means rotates in counter clockwise direction in UV release condition or shunt release and the latch pin which is mounted on the actuator is pushed up.
The latch pin is stopped by the UV latch or shunt latch.
The UV latch or shunt latch surface is horizontal such that horizontal surface of the latch when come in contact with the latch pin, the reaction generated due to main spring will be exactly vertical.
The latch pivot vertical reaction force is passed through the pivot of the latch and there will be no torque generated on the UV latch or shunt latch component and that keeps the entire assembly in latched condition.
The UV latch or shunt latch rotates in clock wise direction during the output of the electromagnetic section of UV release or shunt release and the latch starts rotating in horizontal surface of the UV latch or shunt latch that will start inclining.
The UV latch or shunt latch inclination of the surface changes the reaction force inclination, which creates the torque on the latch, which is in same direction of the UV latch, or shunt latch rotation.
The UV latch or shut latch rotation allows the movement of the actuator pin and the amplified output force is transferred to the circuit breaker mechanism for tripping.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The following drawings are illustrative of particular examples for enabling methods of the present invention, are descriptive of some of the methods, and are not intended to limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description.
Figure 1 illustrates UV release in latched condition 1, Side-plate 2, Actuator pin 3, Actuator 4, Latch pin 5, UV Latch 6, Main spring 7, Spring pin 8, Bias spring 9, and Electromagnet 10.
Figure 2 illustrates UV release in de-latched condition 1A.
Figure 3 illustrates UV release latched 6, latching profile 6A, latch end 6B & resetting profile 6C on latch.
Figure 4 illustrates shunt release in latched condition 11, Side-plate 2, Actuator pin 3, Actuator
4, Latch pin 5, Shunt Latch 12, Main spring 7, Spring pin 8, Bias spring 9, and Electromagnet
10.
Figure 5 illustrates Shunt release in de-latched condition 11A.
Figure 6 illustrates shunt release latched 12, latching profile 12A, latch end 12B & resetting profile 12C on latch.
Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWING
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art

will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
It is to be understood that the singular forms "a," "an," qnd "the" include plural referents unless the context clearly dictates otherwise.
By the term "substantially" it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.
The mechanism consists of a latch, actuator, latch pin, spring pin and actuator pin. All the pins are mounted on side-plate. Actuator is mounted on actuator pin and its other end carries latch pin. The latch pins travel is limited inside the slot in side plate. A main spring is connected between the spring pin and actuator which will rotate the actuator in anticlockwise direction. The latch is mounted on the spring pin and its rotation is controlled by a biasing spring. The profile change of this latch enables the interchangeability between the UV and Shunt release. Hence in UV Release, UV Latch will be assembled & in shunt release shunt latch will be assembled and all other components will remain same.
The fig: 1 shows the UV release in latched condition. In this condition the main spring which is connected between the actuator and the spring pin, is in loaded condition. Hence the actuator is rotated in counter clockwise direction and the latch pin which is mounted on the actuator is now pushed upward. But since this latch pin is stopped by the latching surface (6a) of UV latch, there will be no relative motion between the mechanism components. The latch pin is stopped because the reaction force generated when the latch pin and latching surface comes in contact, is passing through the pivot of the latch. Hence there will be no torque generated on the latch component and also the latch pin is kept in latched condition.

The UV latch is shown in the fig:3. In this latch the profile of the latching surface is kept horizontal. The position of the latch is decided such that horizontal surface of the latch when come in contact with the latch pin, the reaction generated due to main spring will be exactly vertical. Also this vertical reaction force is passed through the pivot of the latch. So there will be no torque generated on the UV latch component and that keeps the entire assembly in latched condition. As already mentioned, the output of the electromagnetic section of UV release rotates the UV latch in clockwise direction. When the latch starts rotating horizontal surface of the UV latch will start inclining. This inclination of the surface changes the reaction force inclination which creates the torque on the latch which is in same direction of the UV latch rotation. This rotation of the UV latch now allows the movement of the actuator pin and goes to position as shown in Fig: 2. This amplified output force is transferred to the circuit breaker mechanism for tripping.
The fig: 4 show the Shunt release in latched condition. In this condition, like in UV release, the main spring which is connected between the actuator and the spring pin, is in loaded condition. Hence the actuator is rotated in counter clockwise direction and the latch pin which is mounted on the actuator is now pushed up. But this latch pin is stopped by the Shunt latch there will be no relative motion between the mechanism components. The Shunt latch is shown in the fig: 6, in this latch the profile of the latching surface is kept horizontal. The position of the latch is decided such that horizontal surface of the latch when come in contact with the latch pin, the reaction generated due to main spring will be exactly vertical. Also this vertical reaction force is passed through the pivot of the latch. So there will be no torque generated on the UV latch component and that keeps the entire assembly in latched condition. As already said, the output of the electromagnetic section of Shunt release rotates the Shunt latch in counter-clockwise direction. When the latch starts rotating horizontal surface of the shunt latch will start inclining. This inclination of the surface changes the reaction force inclination which creates the torque on the latch which is in same direction of the Shunt latch rotation. This rotation of the Shunt latch now allows the movement of the actuator pin and goes to position as shown in Fig:4. This amplified output force is transferred to the circuit breaker mechanism for tripping.
While breaker reset it will moves the latch pin against the main spring force, it roll over the latch surface 6C in case of UV Release & 12C in case of shunt release which will rotate the latch away from the slot and the latch pin reaches the bottom of the slot. This will in turn load the main spring which offers the trip force. Hence the same mechanism can be used for both the

products by modifying the profile of the latch. Thus a common amplification mechanism has been designed.
Features:
• Innovation consists of an Amplification mechanism.
• Common amplification mechanism can be used by modifying the latch profile.
• Latch profile ensures zero torque generated during latching condition.
• Invention requires lesser de-latching force.
• Minimum number of components.
• Reduces component variants.
• Common operating principle.

WE CLAIM
1. A Common Amplification mechanism for Under-Voltage Release & Shunt Release,
said mechanism comprising:
a side plate;
plurality of pins mounted on said side plate, said plurality of pins comprises latch pin, spring pin and actuator pin;
a actuator means mounted on said actuator pin and said actuators other end carries latch pin;
a main spring connected between said spring pin and actuator adapted to rotate actuator in anticlockwise direction; and
a latch mounted on said spring pin and its rotation is controlled by a bias spring such that said latches profile is changed adapted to enable interchangeability between under voltage(UV) release and shut release;
said latch comprises of UV latch and shunt latch , said UV latch assembled in said mechanism during UV release and said shunt latch assembled during shunt release.
2. Mechanism as claimed in claim 1 wherein said latch pin travelling is limited inside
said slot off side plate.

3. Mechanism as claimed in claim 1 wherein said actuator means rotates in counter clockwise direction in UV release condition or shunt release and said latch pin which is mounted on said actuator is pushed up.
4. Mechanism as claimed in claim 3 wherein said latch pin is stopped by said UV latch or shunt latch.
5. Mechanism as claimed in claim 1 wherein said UV latch or shunt latch surface is horizontal such that horizontal surface of the latch when come in contact with the latch pin, the reaction generated due to main spring will be exactly vertical.
6. Mechanism as claimed in claim 5 wherein said latch pivot vertical reaction force is passed through the pivot of the latch and there will be no torque generated on the UV latch or shunt latch component and that keeps the entire assembly in latched condition.
7. Mechanism as claimed in claim 1 wherein said UV latch or shunt latch rotates in clock wise direction during the output of the electromagnetic section of UV release or shunt release and said latch starts rotating in horizontal surface of the UV latch or shunt latch that will start inclining.
8. Mechanism as claimed in claim 1 said UV latch or shunt latch inclination of the surface changes the reaction force inclination which creates the torque on the latch which is in same direction of the UV latch or shunt latch rotation.
9. Mechanism as claimed in claim 1 wherein said UV latch or shut latch rotation allows the movement of the actuator pin and the amplified output force is transferred to the circuit breaker mechanism for tripping.
10. Mechanism ad claimed inn claim 1 wherein said latch pin moves the against the main spring force While breaker is reset and it roll over the latch surface (6C) in case of UV Release & (12C) in case of shunt release which will rotate the latch away from the slot and the latch pin reaches the bottom of the slot and turn load the main spring which offers the trip force.

11. A Common Amplification mechanism for Under-Voltage Release & Shunt Release as herein substantially described and illustrated with the accompanying drawings.