FORM 2
THE PATENTS ACT, 1970 PROVISIONAL SPECIFICATION
(See Section 10)
FLAPPABLE OPERATORS HANDLE FOR A SWITCHING DEVICE
Numbered as dated
INVENTORS:
a) SHUBHO SANYAL
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

FLAPPABLE OPERATOR HANDLES FOR A SWITCHING DEVICE
A) Technical field
[0001] The embodiments herein generally relate to electrical power supply and more specifically to operator handles for a switching device.
B) Background
[0002] Switching devices such as circuit breaker, switch fuses , changeovers and like are generally used to provide protection against over current, under voltage supply and or line leakages to the end product. These electrical switching devices typically have two operating handle positions corresponding to status of the separable contacts. For example, these positions include an "ON" position, in which the separable contacts are closed and an "OFF" position in which the contacts are open. Some switching devices have a third position which corresponds to a tripped condition in which the contacts are tripped open.
[0003] Switching devices are usually installed in an enclosure so that the entire control and distribution network arranged in the form of metallic sheets and/or cable wires are housed inside the enclosure. All the operating means are arranged outside the enclosure to prevent an access to the high voltage sections
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to eliminate the generation of a potential hazard. It is often desirable or essential that the settings of the switching devices remain undisturbed during a maintenance operation. Unauthorized or inadvertent changing of the position of these breakers could result in unwanted interruptions to service or operations and serious damage to an electrical apparatus, or even serious harm to a person. For example, accidental actuation of a circuit breaker might result in electrocution or shock to a workman performing electrical work or repair on equipment downstream from the circuit breaker.
[0004] The operating means hence forth called as handle are mounted outside the enclosure and are connected by means of a connector shaft to the device located inside the enclosure. Thus when a handle is operated from outside the enclosure, the motion is directly transmitted to the operator resulting in a change of state of the operator. It is often seen that the forces requited to operate such operator is extremely high and results in fatigue on person operating. This kind of phenomenon is abundant in places where the switching devices are of very higher current ratings.
[0005] Existing solutions have taken care of this problem by increased length of the handle as this enabled to have higher torque levels generated to operate the switching device. Today with switching devices becoming more and more compact, the option of providing a long handle for operation is contradicting the philosophy of compactness.
[0006] While the conventional solutions are advantageous for their intended
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purposes, the existing state of the art generally does not provide adequate solutions for the same.
[0007] Hence, there is a need to develop a system and mechanism for producing higher torque levels in a compact handle operator for switching device.
C) Object of the invention
[0008] An object of the invention is to provide a compact handle operator for switching device that produces higher torque levels.
[0009] An object of the invention is to provide of pad lock in OFF/ON state to the design configuration.
[0010] Another object of the invention is to provide a door interlocking system when the handle operator is operated to an ON state.
D) Summary
[0011] The embodiments herein provide a flappable operator handle for switching device that can produce higher torque. Since switching devices are installed inside and are operated from outside the enclosure, it is mandatory
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requirement to have door interlock in "ON" state. To add to this, there has to be a provision of defeat by a tool (being performed intentionally by the operator), where door opening is possible even in "ON" state. This is provided for a trained operator to carry on operations even when the switch is "ON". To introduce safety and non intended switching /tempering of a switching device's position, handle is provided with a possibility to lock its operation by plurality of pad locks. The padlocking is further extended to an interlocking of operator handle to switching device in "OFF" condition where door gets interlocked even if its is pad locked so as to have full proof. This feature is optional and hence user has a choice to have door interlock in "OFF" state with padlock. Finally all these features are packed in a compact operating handle that would flip open for the operation and can be closed back.
[0012] The present configuration also converts a one hand operation of a switching device to a two hand operation of a switching device where the force by the operator is converted to a couple thus leveraging the applied force and hence reducing the operational fatigue on the part of the operator.
[0013] 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
[0014] The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which:
[0015] FIG. 1 illustrates a general scenario of a operating handle mounted on an enclosure;
[0016] FIG. 2 illustrates two images showing the arrangement of components while the handle is closed and while the handle is flipped open;
[0017] FIG. 3 illustrates isometric view of the handle flipped sub-assembly;
[0018] FIG. 4 illustrates isometric view of the handle assembly as seen from the side;
[0019] FIG. 5 illustrates back isometric view of the handle assembly as seen from the back;
[0020] FIG. 6 illustrates a cut section of the handle by a vertical plane;
[0021] FIG. 7 illustrates pad locking mechanism;
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[0022] FIG. 8 illustrates door interlock and defeat operation;
[0023] FIG. 9 illustrates door interlock and defeat operation shown from different angle ;
F) Detailed description
[0024] 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.
[0025] The embodiments herein provide a flappable operator handle for switching device that can produce higher torque. Since switching devices are installed inside and are operated from outside the enclosure, it is mandatory requirement to have door interlock in "ON" state. To add to this, there has to be a provision of defeat by a tool (being performed intentionally by the operator), where door opening is possible even in "ON" state. This is provided
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for a trained operator to carry on operations even when the switch is "ON". To introduce safety and non intended switching /tempering of a switching device's position, handle is provided with a possibility to lock its operation by plurality of pad locks. The padlocking is further extended to an interlocking of operator handle to switching device in "OFF" condition where door gets interlocked even if its is pad locked so as to have full proof. This feature is optional and hence user has a choice to have door interlock in "OFF" state with padlock. Finally all these features are packed in a compact operating handle that would flip open for the operation and can be closed back.
[0026] FIG 1 represents a general scenario of an operating handle mounted on an enclosure. Enclosure 1 houses the switching device 2, connected by a rod 3 to operating handles 4 mounted on enclosure. The front face of the door is made transparent to visualize the arrangement to switching devices 2 and their operating handles 4.
[0027] FIG 2 represents two images showing the arrangement of components while the handle is closed and while the handle is flipped open. Handle while is flipped open, forms a two hand held operator represented by two parts. Fixed portion of handle is represented as 5 and flappable portion of handle is represented by 6 in the figure. The general construction of these handles comprises of these being mounted on a square portion called as e- plate 7 that houses all interlocking elements. Handle portion 5 is provided with a pointer 8 that physically corresponds to the state printed on the e-plate 7.
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[0028] FIG 2 also features the pad locking lever 9 that has an interlocking dongle represented by 9A. The handle portion fixed has a profiled slit 5A so that when the handle is closed and pad locked, it cannot be flipped open. Next to the profiled slit 5A, there is a little bump 5B, that ensures that pad locked lever can be pulled only when the flappable portion is closed. The bump corresponds to a corresponding slit 6A on the flappable handle 6.
[0029] FIG 3 represents the isometric view of the handle flipped sub-assembly. Handle portion 5 and handle portion 6 are held hinged by a pin 10. So the handle while being flipped rotates about the axis passing through pin 10. Locking tag 9 slides in and out and is held in place by a tension spring 11. This always keeps the locking tag pulled in. Locking tag is characterized by a slot 9A intended for slipping the pad locks. There is tag stopper 12 that doesn't allow the locking tag 9 to slide. It only allows it to slide after is gets pressed from beneath by bump 5B. This feature allows the movement of the locking tag only on the condition of handle kept closed. The tag stopper 12 is pressed and kept in its free state by a compression spring 13. The entire assembly is closed by a snap fit cover 14.
[0030] FIG 4 represents an isometric view of the handle assembly as seen from the side. Handle portion 5 has a grooved slot to locate the stopper pin 16 which slides up and down. It actually gets is motion from the sliding motion of locking tag 9. The locking tag 9 is characterized by a hook 9A that does two functions. One, it transmits the horizontal sliding motion to the vertical sliding motion of the stopper pin. This is achieved the wedge 16A. The stopper pin is
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kept in state of pushed back by a compression spring 17.
[0031] FIG 5 represents the back isometric view of the handle assembly as seen from the back. Connector rod 3 gets engaged with coupler 15 having corresponding recess to receive pin 16 fitted to connecting rod 3. Coupler 15 is screw fixed to the handle portion 5 from the back, with e-plate 7 sandwiched between them. Hence after screwing, coupler 15 and the handle portion 5 become one integrated sub assembled body and e-plate 7 is kept loose to rotate. Interlocking assembly 18 characterized by two bent plate 18A with slots 18B and 18c to allow entry of the shaft rod 3 fitted with pin 16. The assembly is also characterized by two whole intended for locking / interlocking in "OFF" state. This assembly is placed on the e-plate 7 with the pin 9 getting into the slot of the defeat lever 20. Defeat lever 20 is place in a groove that allows it to slide against a compression spring 21. A push to the defeat lever 21 enables the interlocking assembly to rotate about the central axis. E-plate 7 has three holes within the circumferential profile that accepts stopper pin 16 fitted on handle portion 5. Two of these hole are blind while one of them is a through hole that has a transmitter pin 22 fitted with a compression spring 23 and locked in state by a circlip 24. The entire assembly is closed from back by a back plate 25 by screwing it to the e-plate 7.
[0032] FIG 6 represents a cut section of the handle by a vertical plane. Handle portions 6 and 5 are hinged about a pin 10. Fixed portion of the handle 5 is fixed to coupler 15 by a screw 16. By this handle 5 is positively connected with coupler 15. Hence a rotational torque to the handle is directly transmitted to
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the coupler holding the connecting shaft which in turn operates the switching device.
[0033] The phenomenon of pad locking is explained with reference to FIG 6 and FIG 7. Locking tag 9 is pulled out resulting in pushing the stopper pin 16 downwards due to the wedge shape on the top. Compression spring 17 normally keeps the stopper pin pressed up. Once the locking tag is pulled and the stopper pin moves down it gets into the hole 7A and hence the rotation of the handle 5 is restricted.
[0034] The operation of door interlock and defeat is explained with reference to FIG 8 and FIG 9. The connector shaft 3 with the pin 16 gets into the slot in the interlocking plate assembly in "OFF" state of the switching device. In this position the shaft there is no interlocking between the door and the switching device mounted along with the shaft.
[0035] Incase of off pad lock with door interlock, the element 20 needs to be pushed. This is done by a small hole provided on e-plate 7. Once pushed, this rotates the interlocking assembly 18 and the pin gets trapped beneath. Now if the locking tag is pulled, as usual this results in pushing of the stopper pin 17 and further this pushes pin 21. This gets in-between the second hole on the interlocking plate assembly 18 and doesn't allow the assembly to rotate back. Hence till all the time the pad lock is removed from the locking tag, door gets interlocked.
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[0036] 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
Dated this the 28TH day of March, 2007

Rakesh Prabhu,
Patent Agent, 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
[0037] A flappable operator handle for switching device that can produce higher torque. A handle is provided with a possibility to lock its operation by plurality of pad locks to introduce safety and non intended switching /tempering of a switching device's position. The padlocking is further extended to an interlocking of operator handle to switching device in "OFF" condition where door gets interlocked even if its is pad locked so as to have full proof. This feature is optional and hence user has a choice to have door interlock in "OFF" state with padlock. All these features are packed in a compact operating handle that would flip open for the operation and can be closed back.
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