F O R M 2
THE PATENTS ACT, 1970
(39 of 1970) &
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention: AN IMPROVED MANUAL OVER RIDE AND PADLOCK MECHANISM FOR CHANGE OVER SWITCH
2. Applicant(s):

(a) NAME : LARSEN & TOUBRO LIMITED
(b) NATIONALITY : An Indian Company
(c) ADDRESS : L & T House, Ballard Estate, Mumbai 400 001,
State of Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
The present invention relates to operated MCCB’s, changeover switches and Automatic transfer switches. Particularly, the present invention relates to a mechanism for operating change over switches. More particularly the present invention relates to an improved Manual over ride and Padlock mechanism in Motor operator for Change over switch.
BACKGROUND AND PRIOR ART OF THE INVENTION
In current technologies, to achieve manual override of the electrically operated system, the following techniques are used.
Manual over ride is nothing but a process of disconnecting the automatic operation of the switch or any product. Padlocking is a process in which locking the switch at any position (I -0 - II) in such a way that actuating shaft cannot be moved or rotated further.
US 6,021,691 discloses a window operating system for moving a vehicle window up and down that includes an electric drive motor having a gear coupled to a window movement mechanism through a magnetic clutch assembly wherein the drive gear includes a crank extending outwardly there from and through the door facing surface and is selectively connectable to a roll up crank having a fold out handle and a protruding socket member. The door facing surface includes a cavity or chamber into which the emergency crank can be stored and rapidly retrieved in an emergency. The magnetic clutch is only engaged when the power is supplied to the electric motor in either direction. Magnetic clutch concept which is described in US ‘691where electro magnet is used.
US 7,066,301 discloses a manual override mechanism is presented for a motor-driven linear actuator that allows the output rack and pinion of the actuator to be manually positioned. Once positioned, the output may be locked by a locking mechanism to prevent this output from translating to its quiescent position. When incorporated in a spring-return linear actuator, the manual override may be used to apply a preload on the spring before the driven

device is connected. When the actuator is used to drive a valve or damper, the preload applies a positive closing force on the valve or damper in its zero position to ensure a tight closure of the valve or damper. The locking mechanism engages the gear train and opposes the closing force applied by the spring return of the actuator. To disengage the locking mechanism automatically, the motor applies a forward kick to the gear train. Manual disengagement is also provided. Spring return concept which is described in US ‘301 .
US 5,861,784 discloses a remotely controllable circuit breaker device for interrupting current in a circuit path between a source and a load includes local and remote monitoring capabilities and a gear mechanism for reliable remote control of the interruption mechanism. The device includes a first contact and a second contact cooperatively arranged in the circuit path so as to provide current from the source to the load. At least one of the contacts is disposed on a contact carrier which is movable for interrupting the current provided to the load. The gear mechanism includes a motor with a rotatable shaft which responds to open and closed control signals generated from a remote location, and a gear, rotatably responsive to the rotatable shaft, for controlling the contact carrier so that the circuit path is interrupted and established, respectively. The gear mechanism controls the contact carrier using a coupling arrangement, which has a first part coupled to the contact carrier and a second part coupled to the gear. A manual override mechanism is utilized to render the coupling arrangement non-responsive to the motor. The manual override mechanism includes a manually operated member interlocked to a slide mechanism which is coupled to the gear. The slide mechanism and gear being in one position to enable the remote control mechanism to be responsive to remote control signals and in another position to disable the remote control mechanism to render it non-responsive to the remote control signals. The manually operated member is biased by a spring so that when it is released from a fixed position it pulls the slide mechanism and thusly the gear into a position where the gear no longer will move the contact carrier in response to rotation of the motor shaft.Biased spring concept which is described in US ‘784.
US 4,895,048 discloses a powered actuator (1) for driving mechanisms that open and close convertible tops, sunroofs, windows and the like in motor vehicles; in which actuator (1) has a manual override feature allowing actuator (1) to be easily operated by hand should the

electrical power system of the motor vehicle fail, yet the manual override feature does not require calibration or periodic adjustment. Actuator (1) includes actuator housing (2) having an attached motor having first gear (28) driven by the motor armature, output shaft (18) having driven gear (12) mounted thereon, insert cushion (10) being engaged with driven gear (12), and removable plate (6) being installed upon plate end (42) of output shaft (18). Actuator (1) is manually operated by removing removable plate (6) thereby disengaging driven gear (12) from output shaft (18) and then manually imparting rotation to plate end (42) of output shaft (18). Because driven gear (12) is disengaged from output shaft (18) in the manual mode, the motor armature does not resist the manually imparted rotation of output shaft (18).
Removing the Removable plate which connects the motor operation to the product. This concept is explained in US ‘048
The drawbacks of the above mentioned prior art is that the motor operation and manual operation are isolated only by providing a separate component. Moreover separate attention is needed to do isolation. That is, both isolation and manual operation are separate processes and cannot be executed in one stroke.
Thus there is a need to provide a handle for operating the switch manually. The present inventors found that while inserting the handle into the common shaft, motor is automatically disconnected from common shaft by a spring loaded gear which is directly associated with the motor operation.
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 manual override and padlocking concept in Motor operator for change over switches and MCCBs.
Another object of the present invention is to provide a manual and motor operation in mutually exclusive manner.

Yet another object of the present invention is to provide an improved Manual over ride and Padlock mechanism in Motor operator for Change over switch.
Yet another object of the present invention is to provide a mechanism to separate the electrical and manual operation in the manner of mutually exclusive without affecting the performance of the product.
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
According to one of the aspect of the present invention an improved manual override mechanism, said manual override mechanism comprising :
a motor adapted to provide an output torque;
a gear train means operatively connected with said motor;
a shaft means substantially placed within said gear train adapted provide support to said gear train means, said shaft means comprising a locking hole ;
a driven gear means substantially placed with said shaft means , said gear means comprising a spring means ,said driver gear means is operatively loaded with said spring means;
a handle means being fixed on a handle guide means adapted to get engaged and/or disengaged with said shaft means , said handle is having a projection to push down the driven gear means, said handle means is substantially accommodated inside said shaft means
such that said handle means when removed from said shaft means the driven gear means automatically comes up and gets engaged with the gear train and when said handle is

pushed/inserted into said shaft means then said motor is automatically disconnected from shaft means by said driver means.
According to another aspect of the present invention an improved padlocking mechanism , said padlocking mechanism comprising :
a motor adapted to provide an output torque;
a gear train means operatively connected with said motor;
a shaft means substantially placed within said gear train adapted provide support to said gear train means, said shaft means comprising a locking hole ;
a driven gear means substantially placed with said shaft means , said gear means comprising a spring means ,said driver gear means is operatively loaded with said spring means;
a handle means being fixed on a handle guide means adapted to get engaged and/or disengaged with said shaft means , said handle is having a projection to push down the driven gear means, said handle means is substantially accommodated inside said shaft means
a locking arrangement positioned substantially on said gear train means, said arrangement
comprising :
a support means;
a locking pin substantially placed on said support means adapted to slide/move freely on said
support means, said pin comprising a hole;
an energy storing element is substantially placed between said support means and locking pin
means ;
a lock means;
such that said locking pin when pushed ,then said compression spring gets compressed and said pin accommodates the hole of said support means and hole of said shaft means and gets

locked by a lock to prevent further rotation of said shaft, said hole of locking pin is matched with hole of support means to get locked.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to an improved Manual over ride and Padlock mechanism in Motor operator for Change over switch.
A handle is used for operating the switch manually. While inserting the handle into the common shaft, motor is automatically disconnected from common shaft by a spring loaded gear which is directly associated with the motor operation. Design of the connecting gear is having the same property of the gears which are used in the gear train. No special attention is required to do the isolation.
The design of the handle is having a pushing projection to push down the spring loaded gear and moreover after pushing down the gear, shaft will be connected with the handle. If the handle is removed, the spring loaded gear automatically comes up and engages with the gear train which is associated with the motor operation. The present invention overcomes the usage of separate component and increases the reliability.
The electrical switches and MCCB’s can be operated both manually and by motor, at the same time both operations should be mutually exclusive. So that one operation will not load the other one.
In the present invention, to achieve manual operation, specially designed handle and spring loaded gear are used. While inserting the handle into the common shaft, motor is automatically isolated from common shaft by a spring loaded gear which is associated with the motor operation.
This concept is designed for Changeover switch which operates at 50° intervals, i.e. switch will move from one position to another by the 50° angular rotation.

The spring loaded gear has been designed in such a way that it can be exactly matched with the gear train after 50° or 100° rotation of the switch i.e. the teeth of both driven and driving gear will engage exactly. So motor operation can be isolated or resumed again after 50° or 100° rotation.
Driven gear is the manual overloaded gear and driver gear will be the final gear. Padlocking is done by physical support of the frame, pin, lock and a compression spring. In normal condition spring loaded pin will be at unlocked position. While inserting the pin in to the hole of the shaft, compression spring is compressed and the pin is locked with the hole of the physical support by a lock. Lock is shown in fig. 9.
According to one of the embodiments of the present invention there is provided an improved manual override mechanism . the manual override mechanism comprises a motor adapted to provide an output torque , a gear train means operatively connected with the motor , a shaft means substantially placed within the gear train adapted provide support to the gear train means where shaft means comprises a locking hole, a driven gear means substantially placed with the shaft means where the gear means comprises a spring means where the driver gear means is operatively loaded with the spring means , a handle means being fixed on a handle guide means adapted to get engaged and/or disengaged with the shaft means where the handle is having a projection to push down the driven gear means such that handle means is substantially accommodated inside the shaft means .
The handle means when removed from the shaft means the driven gear means automatically comes up and gets engaged with the gear train and when the handle is pushed/inserted into the shaft means then the motor is automatically disconnected from shaft means by the driver means.
The output torque of the motor means is provided to the gear train means adapted to multiply the torque. The gear train comprising a driver gear means adapted to get engaged and/or disengaged with the driven gear. The driven gear automatically comes up and engages with the driver gear from 50˚ to 100˚ angular rotation. The angular rotation is 50˚. The spring means adapted to support the driven gear to be engaged with the driver gear of gear train means. The driven gear means comprising plurality of slots and plurality of teeth to get

engaged with the driver gear. The driver gear means comprising plurality of slots and plurality of teeth to get engaged with the driven gear.
According to another embodiments of the present invention there is provided an improved padlocking mechanism . the padlocking mechanism comprises a motor adapted to provide an output torque , a gear train means operatively connected with the motor , a shaft means substantially placed within the gear train adapted provide support to the gear train means where shaft means comprising a locking hole , a driven gear means substantially placed with the shaft means where the gear means comprising a spring means where driver gear means is operatively loaded with the spring means , a handle means being fixed on a handle guide means adapted to get engaged and/or disengaged with the shaft means where the handle is having a projection to push down the driven gear means where handle means is substantially accommodated inside the shaft means , a locking arrangement positioned substantially on the gear train means.
The locking arrangement comprises a support means , a locking pin substantially placed on the support means adapted to slide/move freely on the support means where the pin comprising a hole , an energy storing element is substantially placed between the support means and locking pin means and a lock means .
The locking pin when pushed ,then the compression spring gets compressed and the pin accommodates the hole of the support means and hole of the shaft means and gets locked by a lock to prevent further rotation of the shaft, the hole of locking pin is matched with hole of support means to get locked. The energy storing element comprising compression spring. The output torque of the motor means is provided to the gear train means adapted to multiply the torque. The gear train comprising a driver gear means adapted to get engaged and/or disengaged with the driven gear. The driven gear automatically comes up and engages with the driver gear from 50˚ to 100˚ angular rotation. The angular rotation is 50˚. The spring means adapted to support the driven gear to be engaged with the driver gear of gear train means. The driven gear means comprising plurality of slots and plurality of teeth to get engaged with the driver gear. The driver gear means comprising plurality of slots and plurality of teeth to get engaged with the driven gear.

Features and benefits of the present invention
• Mutually exclusive manual and motor operation and no separate component are required to achieve this feature.
• No need of special attention to isolate the manual and motor operation.
• After 50° rotation, the driven gear automatically comes up and engages with the driver gear. There is no need of further rotation to make them engaged.
• Independent Padlocking concept (i.e. Padlocking is not depending up on manual and motor operation).
• Specially designed spring loaded gear for isolating manual and motor operation.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Other features as well as the advantages of the invention will be clear from the following description.
In the appended drawing:
Figure 1 illustrates the front view of the motor operator with removable handle and handle
guide.
Figure 2 illustrates the exploded view of motor operator and removable handle with handle
guide.
Figure 3 illustrates the front view of motor operator with mechanism of changeover switch.
Figure 4 illustrates the engagement of override gear with the final gear of gear train.
Figure 5 illustrates the engagement of override gear with the gear train and hence with motor
operation.
Figure 6 illustrates the disengagement of override gear with gear train as well as with motor
and connected with shaft when the handle is inserted.
Figure 7 illustrates the motor operator in unlocked position.
Figure 8 illustrates the motor operator in locked position .

Figure 9 illustrates the lock.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWING
In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and illustrate the best mode presently contemplated for carrying out the invention. Further functioning of the mechanism has been discussed below to describe the way the mechanism operates. However, such description should not be considered as any limitation of scope of the present mechanism. The structure thus conceived is susceptible of numerous modifications and variations, all the details may furthermore be replaced with elements having technical equivalence. In practice the materials and dimensions may be any according to the requirements, which will still be comprised within its true spirit.
Changeover switch is used for connecting load with any one of the source among two independent sources (for example EB supply and emergency ie,Genset supply). To transfer the load between two sources, mechanism is used. This mechanism can be operated either manually or by a motor operator which is for remote operation. Mechanism is connected with motor operator by using main shaft.
Load: In this context describe the electrical equipment which consumes power. Such as Motor, Fan, Air conditioner, etc.
Source: In this context it describes about the Electrical supply. It may be supplied by the electricity board (E.B) or it can be generated by in house Diesel Generator (D.G) in case of power failure.
Need for Changeover switch: If a load is connected to the E.B with a help of a switch the load draws power only from E.B, if Power fails the load will stop consuming power.
When the changeover switch mechanism is operated by motor operator, the output torque of motor is given to the gear train for multiplying the torque and then the torque at final stage is given to the mechanism with the help of shaft.

Figure 1 shows the front view of the motor operator with removable handle (1) and handle guide (2) . Handle guide (2) is always fixed with the handle (1) . Whenever the supply is given to the motor (7) , it rotates the gear train (5) and the total output torque from gear train
(5) is given to the shaft(8). Shaft (8) drives the mechanism of changeover switch (13). Spring
(6) supports the manual override gear (4) to be engaged with the final gear (14) of gear train (5) .
Figure 2 shows the exploded view of motor operator and removable handle (1) with handle guide (2) . Padlocking provisions are also shown here. More over the slot and teeth made for engaging the override gear (4) with final gear (14) is shown here. Manual override gear (4) is tightly fitted with the shaft (8) , so that it rotates the shaft and hence the mechanism.
Figure 3 shows the front view of motor operator with mechanism of changeover switch. Here handle(1) is inserted and the shaft (8) is connected with handle(1) by using handle guide(2) . So that motor (7) with gear train (5) is disconnected from the shaft (8) because of manual override gear(4) . If the shaft (8) is rotated manually, it makes the mechanism to operate and the load is connected with any one of the sources with respect to the direction of rotation of the handle( 1).
Figure 4 shows the engagement of override gear with the final gear of gear train (5) . When the final gear (14) rotates, engaged manual over ride gear (4) also rotates and hence shaft (8) is rotated. The shaft (8) drives the mechanism of changeover switch (13).
If the manual over ride gear (4) is pushed down by handle(1) , then the handle (1) gets engaged with the shaft(8) . Now handle (1) rotates the shaft by 50° (Operating angle of changeover switch for connecting the load from one position to another) and makes the load connected with any one of the positions (I-0-II).The over ride gear (4) also rotates by 50° because of tight fit with the shaft(8) . If the handle (1) is taken out, the over ride gear (4) is pushed up and engages with the final gear (14) by the compression spring (6) . The rotation whether it may be 50° or 100° by handle(1) , the override gear (4) gets engaged with final gear. The engaged gear positions are shown in fig.4 after 50° clockwise and anticlockwise rotation.

Figure 5 shows the engagement of override gear (4) with the gear train (5) and hence with motor operation. So that mechanism of changeover switch is operated by motor (7) . When the supply is given to the motor (7) , it rotates the gear train(5) , torque at each stage is multiplied and finally given to the shaft (8) .
Figure 6 shows the disengagement of override gear (4) with gear train (5) as well as with motor (7) and connected with shaft (8) when the handle (1) is inserted. Now the spring (6) will be in compressed state. Handle (1) rotates the shaft (8) and hence the mechanism of changeover switch (13) . With this arrangement, the motor (7) is not affected by the rotation made by handle(1) .
Figure 7 and 8 shows the motor operator in unlocked and locked position respectively.
Generally padlocking is done if the load is to be isolated or if any maintenance work has to be carried out on a switch. By this high protection is given to the maintenance people.
Padlocking is done by a physical support (9) on the frame of motor operator, a movable locking pin (3) , lock (15) and a compression spring(12) . Physical support (9) is fixed on the frame of motor operator. Locking pin (3) is made to slide on physical support (9) and the spring (12) is located between the physical support (9) and sliding pin (3) .
In unlocked position spring (12) will be in its free length, so that locking pin (3) is not locked with the hole of the shaft(10) . This is shown in fig. 7. In this position, shaft (8) can be rotated and can drive the mechanism of the changeover switch (13).
When the locking pin (3) is pushed, compression spring (12) gets compressed and the hole on the locking pin is matched with the hole of physical support (11) and then locked by a lock. Now the other end of locking pin (3) is inserted in to the hole of the shaft (10) . The shaft (8) cannot be rotated in this position. This is shown in fig. 8.

WE CLAIM:
1. An improved manual override mechanism, said manual override mechanism
comprising :
a motor adapted to provide an output torque;
a gear train means operatively connected with said motor;
a shaft means substantially placed within said gear train adapted provide support to said gear train means, said shaft means comprising a locking hole ;
a driven gear means substantially placed with said shaft means , said gear means comprising a spring means ,said driver gear means is operatively loaded with said spring means;
a handle means being fixed on a handle guide means adapted to get engaged and/or disengaged with said shaft means , said handle is having a projection to push down the driven gear means, said handle means is substantially accommodated inside said shaft means ;
such that said handle means when removed from said shaft means the driven gear means automatically comes up and gets engaged with the gear train and when said handle is pushed/inserted into said shaft means then said motor is automatically disconnected from shaft means by said driver means.
2. Mechanism as claimed in claim 1 wherein said output torque of said motor means is provided to the gear train means adapted to multiply said torque.
3. Mechanism as claimed in claim 1 wherein said gear train comprising a driver gear means adapted to get engaged and/or disengaged with said driven gear.

4. Mechanism as claimed in claim 3 wherein said driven gear automatically comes up and engages with the driver gear from 50˚ to 100˚ angular rotation.
5. Mechanism as claimed in claim 1 wherein said spring means adapted to support the driven gear to be engaged with the driver gear of gear train means.
6. Mechanism as claimed in claim any of the preceding claims wherein said driven gear means comprising plurality of slots and plurality of teeth to get engaged with said driver gear. 7. An improved padlocking mechanism , said padlocking mechanism comprising :
a motor adapted to provide an output torque;
a gear train means operatively connected with said motor;
a shaft means substantially placed within said gear train adapted provide support to said gear train means, said shaft means comprising a locking hole ;
a driven gear means substantially placed with said shaft means , said gear means comprising a spring means ,said driver gear means is operatively loaded with said spring means;
a handle means being fixed on a handle guide means adapted to get engaged and/or disengaged with said shaft means , said handle is having a projection to push down the driven gear means, said handle means is substantially accommodated inside said shaft means ;
a locking arrangement positioned substantially on said gear train means, said
arrangement comprising :
a locking pin substantially placed on said support means adapted to slide/move freely
on said support means, said pin comprising a hole;
an energy storing element is substantially placed between said support means and
locking pin means ;

a lock means;
such that said locking pin when pushed ,then said compression spring gets compressed and said pin accommodates the hole of said support means and hole of said shaft means and gets locked by a lock to prevent further rotation of said shaft, said hole of locking pin is matched with hole of support means to get locked.
8. Mechanism as claimed in claim 9 wherein said energy storing element comprising compression spring.
9. Mechanism as claimed in claim 8 wherein said driven gear automatically comes up and engages with the driver gear from 50˚ to 100˚ angular rotation.
10. An improved manual override mechanism and padlocking mechanism as herein substantially described and illustrated with reference to the accompanying drawings.