FIELD OF THE INVENTION
The present invention relates to a method and system for fail-safe operation of retro-fitted electronically controlled switch. More particularly, the invention provides a fool-proof and fail-safe operation of remotely operated electronic switch thereby operating the electric circuit either via electronic control module or 5 relay while having the full mechanical functionality of the existing switches.
BACKGROUND OF THE INVENTION
Electrical switches are used to control the electricity running through a circuit by turning on and off the power supply, such switches are used in residential and 10 commercial buildings to control lights, fans, home appliances etc. These electrical switches have been around for several years and have undergone relatively few changes to improve their performance. An electrical switch is a manually operated electromechanical device with one or more sets of electrical contacts, which are connected to external circuit. Each sets of contacts can be in one of the 15 two states: either “closed” meaning the contacts are touching and electricity can flow between them, or “open”, meaning the contacts are separated and the switch is non conduction. A switch that is operated by another electrical circuit is called a relay.
Relays are devices for completing or breaking electric circuits by their output 20 section driven by operational signal, which is triggered by electric input signal controlled by switching devices. Relays can be operated both electrically and mechanically. Relays consist of an electromagnet and a set of contacts. The switching mechanism is carried out with the help of the electromagnet. There are also other operating principles for its working but they differ according to their 25 application. Most of the devices have the application for relays.
Although, relays play a vital role in completing or breaking electric circuits, there are some problems in many instances that need to be resolved.
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A Conventional electrical circuit controlled by a relay comprises of an electrical switch that triggers relay upon detecting the switch state (On/Off), the relay then supplies power to the load (Light Bulb, Fan, Tube Light, CFL, Air Conditioner etc.). In general, there is no direct connectivity between the electrical Switch and the Load in the existing switch circuits. Hence, in case, if either electronic control 5 module (ECM) or the relay fails, the load cannot be switched on/off without removing the device and rewriting electrical switch to the load. As a result, user will not be able to control the state of the load or control the electric switch. Such a circuit is prone to failures.
The prior art provides: 10
In US 5738496, a ceiling fan having interchangeable plug-in circuit completion modules for varying the electrical driver circuitry of the fan. Each module is selectively designed to complete a motor driving circuit and/or a light driving circuit and are preferably installed in the switch housing of the fan. In addition, the modules contain selectively designed circuitry to enable a user to either 15 manually or remotely control the fan. Since the modules are interchangeable, the driver control circuitry of the fan may be easily converted between manual and remote control;
In US20110032070, a wireless switching apparatus is provided for three-way switching atleast one energy load with an AC power source. The apparatus 20 comprises a relay controlled by a controller. The controller is also connected to both a toggle and a wireless transceiver. A remote wireless transceiver unit is in communication with the wireless transceiver. The controller operates the relay for making and breaking electrical continuity between the energy load and an AC power source in response to a change in the state of either toggle or wireless 25 signals received from the remote wireless transmitting unit. Control of the energy load using a combined system comprising an energy monitoring device operatively coupled to the apparatus is also provided. Methods are provided for retrofitting conventional receptacles and switches with the wireless switching apparatus; 30
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In CN 2708417, the utility model discloses a wireless remote control coupled twin switch. The switch comprises at least the following circuit: a wireless transceiver control unit connecting into the circuit and controlling the switch of the circuit, and the wireless transceiver control unit comprises a transmitting circuit and a receiving circuit. The transmitting circuit comprises a coding unit, a radio 5 transmitting module and a transmitting antenna. The receiving circuit comprises a receiving antenna, a decoding circuit and a driving control unit electrically connected in turn. The driving control unit controls and connects the switch devices to control the circuit by switches. The utility model can remotely control and manually operate the switch control of the lamp. The utility model has the 10 advantages of simple and convenient operation, simple structure and convenient installation. The utility model can solve the problem of the inconvenient walking of aged people for turning on and off the lamp, and is suitable for using when being inconvenient for switching on or off lamps;
In CN201628853, the utility model relates to a mechanical and electronic double-15 controlled electric switch, which comprises a micro-electronic switch control module and a mechanical switch control module. The micro-electronic switch control module comprises a power supply managing unit, a central controller, a switch detecting unit and a control unit. The mechanical switch control module comprises a selector switch and a manual switch, wherein the manual switch is 20 connected with the selector switch, the selector switch is connected into the central controller via the switch detecting unit of the micro-electronic switch control module, the central controller is connected with and controls the selector switch via the control unit, and the selector switch is further connected with a power input of an external electric device. The electric switch has both the 25 advantage of automated control of a micro-electronic switch and the advantages of simplicity and durability of a mechanical contact switch, when a micro-electronic control device fails and cannot control the electric device, the mechanical contact switch can be manually selected for controlling electric appliances, and when the micro-electronic control portion is repaired, the original 30
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function of the micro-electronic control portion can be recovered via manual selection; and
In CN103197569; the present invention discloses a mechanical electronic integrated switch, comprising: two circuit sections, the first circuit section and the second circuit section; for an electronic switching circuit in a first section and a 5 second circuit section of the electronic switch ; for the first circuit section and the second section of the manual switching circuit mechanical switch; and an electronic switch connected to both ends of the electronic switch for short-circuiting the manual bypass switch. The present invention is machinery and electronics integrated switch, a collection of original mechanical flexibility, 10 reliability and switch electronic switch, mechanical switch and the electronic switch can switch the switch status of the load can be achieved mechanical switch, remote control, or remote start, mechanical clearance and other operations, to the stand-alone operation, the results related to the purpose of solving the electronic switch is not connected to the circuit work segment lead-off 15 technical problems rely on a mechanical switch cannot be achieved switches.
The prior art provides interchangeable plug-in circuit completion modules that allow conversion of manual circuit to automated circuit, however it does not provide seamless fail safe circuit and if the plug-in circuit fails, it needs to be replaced. Further, none of the patent provides logical arrangement of electronics 20 and mechanical switches that in case of a failure provide seamless transition without manual intervention or replacement of the damaged circuit or components.
Therefore, there is a technological gap wherein the prior art provides logical arrangement of electronics to automate or retrofit existing mechanical switch; 25 however, it does not provide any failsafe mechanism or alternate path.
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OBJECT OF THE INVENTION
The main object of this invention is to provide a method and system for fail-safe operation of retro fitted electronically controlled switch by logical arrangement of electronics to and to provide a failsafe mechanism or alternate path; so that if the 5 automatic function does not work the switches act mechanically without changing any parts.
Yet another object of the invention is to provide a method for fool-proof and fail-safe operation of the retrofit smart switch, functioning automatically by regulating the electric circuit either by atleast one electronic control module or relay, but 10 also retaining full mechanical functionality of the existing switches.
Yet another object of the invention is to automate existing mechanical switches while retaining full mechanical functionality.
Yet another object of the invention is to provide a method to provide a device to automate existing Electrical Switches by installing an electronic control module 15 (ECM), which in turn may be operated remotely or wirelessly or other communication means.
Yet another object of the invention is to provide full mechanical functionality to electronically controlled switches so that even if the electronic module or relay fails the switches are still operable. 20
Yet another object of this invention is to provide a method or logic to arrange electronic or solid-state or electro-mechanical relays in a combination so that the traditional switches can be used in manual operation mode as well as in automatic mode.
Yet another object of this invention is to provide a method to ensure an 25 alternative fail-safe path for completing the circuit and hence to provide power supply to the load in case of failure of either an electronic control module or relay.
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Yet another object of the invention is to provide a method to automate existing Electrical Switches in a cost effective manner that is compatible to all the existing switches.
The invention eliminates the need of replacing the physical switches, thus physical switch retain its original mechanical functionality. 5
SUMMARY OF THE INVENTION
The present invention provides a method and system for fail-safe operation of electronically controlled switch used in residential and commercial buildings or any other place where a controlling module is required to switch on/off the 10 power supply. The invention also provides a fool-proof mechanism for operating the electric circuit in case of failure of either electronic control module or relay while having full mechanical functionality of the existing switches.
In an embodiment of the current invention, a method is provided to arrange electronic or solid-state or electro-mechanical relays in a combination with 15 traditional electrical switches allowing them to operate manually as well as in automated switching mode controlled by an electronic control module thereby ensuring fool-proof or fail-safe operation.
According to another embodiment of the present invention comprises atleast one electronic control module in the circuit connected to detect the state of existing 20 switch on the switchboard. A plurality of relays via an electronic control module is connected between load and the electric switch that are activated by electronic control module depending on the state (power On/Off) of the electric switch. The relays that control the operation can be triggered using an electrical signal. The source for the electrical signal is pre wired connection from electronic control 25 module, which in turn may be operated remotely / wirelessly.
According to another embodiment of the invention, a dual path for power supply is provided. The default path from Electrical Switch to Load is always available enabling the load to be controlled by electrical switch in event of Failure. In
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another embodiment of the current invention the system for the novel circuit design comprise of a traditional electrical switch, an electronic control module, a plurality of relays, at least one load and/or a remote means.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 5
Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
Fig. 1 is a schematic plan view of a conventional switch circuit controlled by a relay. 10
Fig. 2 is a schematic plan view of a novel switch circuit according to the present invention wherein a two way electrical path is illustrated.
Fig. 3 is a schematic plan view of the novel switch wherein the fail safe path is illustrated according to the one embodiment of the present invention.
Fig. 4 is a state diagram illustrating various combinations of the relay position 15 depending upon the state of switch/remote.
DETAILED DESCRIPTION OF THE INVENTION
The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the 20 invention are shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
Many modifications and other embodiments of the invention set forth herein will 25 come to mind to one skilled in the art to which the invention pertain having the benefit of the teachings presented in the foregoing descriptions and the associated
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drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. 5
As illustrated in Fig. 1, it provides a schematic plan of a circuit with live wire 6, neutral wire 1 and a conventional switch 5 having electromechanical functionality wherein the circuit powers the load 4 when electricity is relayed to the circuit by electronic control module 2.The electronic control module 2 is connected between electric switch 5 and the relay 3. The electronic control module 2 10 triggers the relay 3 depending upon the state (On/Off) of the switch 5. When the switch 5 is powered On, the electronic control module 2 triggers the relay 3; the relay 3 gets switched from power Off to power On state and hence current flows to the load 4.
As illustrated in Fig. 2, it provides a schematic plan view of the novel switch 15 installed in a circuit with live wire 13 and neutral wire 8.Theplan shows a plurality of relays 10A, 10B that are used in the circuit to provide a two way electrical path for power supply to at least one load 11. The system for the novel circuit design as per the present invention comprises:
a traditional electrical switch 12; an electronic control module 9; a plurality of 20 relays 10A and 10B; at least one load 11;and/or a remote means 16.
The traditional electric switch 12 is connected to the live wire 13 so as to control the circuit independently. The electronic control module 9in the circuit controls the relays 10A and 10B depending upon the state (On/Off) of the traditional electric switch 12 from feedback received on desired voltage probe 17. The 25 electronic control module 9 detects the state of the traditional electrical switch 12 and provides electric signal to the plurality of relays 10A and 10B that draws power towards at least one load 11.
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The source for the electrical signal to the relays 10A and 10B can be wired connection from electronic control module 9, which in turn may also be operated by a remote means 16.
As illustrated in Fig. 3, it provides a schematic plan view of the novel switch installed in a circuit wherein the fail safe path is illustrated. The default state of 5 the relay 10A is P1 and relay 10B is P3, if the electronic control module 9 is not powered or it fails, the relays 10A and 10B will get back to their default states. In case of any failure the default path from the traditional electric switch 12 to at least one load 11 will ensure the connectivity of the circuit. At least one load 11 will be controlled by the traditional electric switch 12 in event of failure. 10
As illustrated in Fig. 4, it provides a state diagram illustrating various combinations of the relay position depending upon the state of switch/remote wherein the state map explains the various possible states of relays as well as transition states as follows:
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State1 is the default state in case of unpowered smart switch or failure.
For state changes from 5-6 and 7-8, desired voltage probe 17 will be used to determine state of the traditional electric switch12.
State 1, State 8: When traditional electrical switch 12 is Off, Relay 10A will be at 20 P1 position and Relay 10B will be at P3 position and no current will flow towards at least one load 11.
State 1 to State 2: Transition State when user switches On the traditional electric switch 12, Relay 10A will be at P1 position and Relay 10B will be at P3 position 25 and current will flow towards at least one load 11.
State 2: When the traditional switch is On, Relay 10A will be at P1 position and Relay 10B will be at P3 position and current will flow towards at least one load 11. 30
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State 3, State 5: When the user uses a remote means 16 to switch On at least one load 11, Relay 10A will be at P2 position and Relay 10B will be at P4 position and current will flow towards at least one load 11.
State 3 to state 4: When the user uses remote means 16 to switch Off the at least 5 one load 11, Relay 10A will be at P1 position and Relay 10B will be at P3 position and no current will flow towards at least one load 11.
State 5 to State 6: When at least one load 11 is already turned On using remote apparatus and traditional electrical switch 12 changes state from off to On, relay 10 10A will be at P1 position and Relay 10B will be at P3 position and current will flow towards at least one load 11.
State 6: When the traditional electric switch 12 is On as well as the remote means 16 is also in On state, the Relay 10A will be at P1 position and Relay 10B will be 15 at P3 position and current will flow towards at least one load 11. This state ensures that if traditional electric switch 12 is turned Off, no current will flow towards at least one load 11.
State 6 to State 7, State 7: When the traditional electric switch 12 is On and the 20 user uses remote means 16 to switch Off at least one load 11, Relay 10A will be at P2 position and Relay 10B will be at P3 position and no current will flow towards at least one load 11. This ensures that traditional electric switch 12 can be over-ridden by remote means 16.
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State 7 to State 8: When the traditional electric switch 12 is turned Off, Relay 10A will be at P1 position and relay 10B will be at P3 position and no current will flow towards at least one load 11.
The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the 30 nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the
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above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. The invention is defined by the claims.

CLAIMS
We Claim:
1. A system for fool-proof and fail-safe operation of a retrofit smart switch comprising of
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a plug-in circuit;
atleast one traditional electrical switch;
an electronic control module;
atleast one relay;
atleast one load; and 10
optionally a remote control means;
wherein:
the plug-in circuit connecting the load to the traditional electrical switch via a 15 single default electrical path having said electronic control module controlling an electrical signal within the circuit connected to detect the state of existing switch on the switchboard and having atleast one electronic or solid-state or electro-mechanical relays connected between the load and the mechanical switch that are activated by said electronic control module 20 depending on the state of power On/Off of the electric switch controlled by the the remote control means;
a failsafe path is provided by adding atleast one additional electrical path in parallel to the default path, connecting the load to the traditional electrical 25 switch having said electronic control module, said or solid-state or electro-mechanical relays and said remote control means;
the failsafe path from the mechanical switch to the load is always available enabling the load to be controlled by traditional electrical switch in event of 30 failure of the plug-in circuit or any additional path; and
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the system provides seamless fail safe circuit and if the plug-in circuit fails or it needs to be replaced.
2. The system as claimed in claim 1, wherein the relays that control the operation can be triggered using an electrical signal. 5
3. The system as claimed in claim 1, wherein the source for the electrical signal has pre-wired connection from electronic control module, which in turn may be operated remotely or wirelessly.
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4. The system as claimed in claim 1, wherein traditional electrical switch are manually operated mechanical switches.
5. A method for providing a fool-proof and fail-safe operation of a retrofit smart switch comprising of steps of 15
incorporating a plug-in circuit with atleast one traditional electrical switch, an electronic control module, atleast one relay, atleast one load and optionally a remote control means;
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allowing the plug-in circuit connecting the load to the traditional electrical switch via a single default electrical path having said electronic control module controlling an electrical signal within the circuit connected to detect the state of existing switch on the switchboard and having atleast one electronic or solid-state or electro-mechanical relays connected between the 25 load and the mechanical switch that are activated by said electronic control module depending on the state of power On/Off of the electric switch controlled by the the remote control means;
wherein: 30
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a failsafe path is provided by adding atleast one additional electrical path in parallel to the default path, connecting the load to the traditional electrical switch having said electronic control module, said or solid-state or electro-mechanical relays and said remote control means; 5 the failsafe path from the mechanical switch to the load is always available enabling the load to be controlled by traditional electrical switch in event of failure of the plug-in circuit or any additional path; and the method provides seamless fail safe circuit and if the plug-in circuit fails or 10 it needs to be replaced.
6. The method as claimed in claim 5, wherein the relays that control the operation can be triggered using an electrical signal.
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7. The method as claimed in claim 5, wherein the source for the electrical signal has pre-wired connection from electronic control module, which in turn may be operated remotely or wirelessly.
8. The method as claimed in claim 5, wherein traditional electrical switch are 20 manually operated mechanical switches.