Title of Invention

"A REPLACEABLE PROTECTING DEVICE FOR ELECTRICAL EQUIPMENTS"

Abstract The present invention provides a replaceable protective device for electrical equipment, comprising : - a first protecting element connected in series with the supply terminal and the electrical equipment. - a second protecting element connected after the said first protecting e lement in parallel to the said electrical equipment. the arrangement between said first protecting element and second protecting element being such that the first protecting element is disabled when either a current more than threshold current flows through it, or when the supply voltage across the second protecting element exceeds its threshold voltage.
Full Text A Replaceable Protecting Device For Electrical Equipment
Field of the Invention:
This invention relates in general to electrical control devices and, in particular, to electrical control devices for providing protection from supply variation to electrical apparatus. More specifically, but without restriction to the particular embodiments hereinafter described in accordance with the best mode of practice, this invention relates to a replaceable protecting device for electrical equipments, from high voltage impulses, that may be employed in conjunction with a wide variety of electrical apparatus including elecfronic instruments like television, telephone, computer, air conditioners, or other integrated circuit based equipment also including power instruments like industrial motors, large-volume air compressors, tanning equipment used in tanning salons, and electrical equipments installed on electrical and telecommunication towers etc, which might be damaged in case of high supply variations.
Background of the Invention:
Today practically all the electrical and electronic equipment are provided with a replaceable protecting fuse for safeguarding the equipments from high supply variation. Whenever a high supply variation is observed the fuse blows off thereby disconnecting the load (equipment) from supply hence protecting it. The fuse can be later replaced by new fuse to resume normal operation. The fuse protects the electrical circuit from getting overloaded and to some extent protects the circuit, hi addition often the equipments are provided with a Metal Oxide Varistor (MOV) for protecting them. The MOVs are generally provided on the Printed Circuit Boards (PCBs) and are connected in parallel with the mains, hi the normal operation of the equipment the MOV shows high impedance and allows no current to flow through it. However, in case of a high voltage surge, the MOV behaves like a short and does not allow a high current to flow through the electrical equipment, thereby protecting it.
An event of high supply variation can result in four different consequences. First, the equipment does not observe or react to the supply variation and remains intact. Second, the fiase
Mows off but the MOV is intact and available to protect the equipment from a future surge. In such a case user can replaces the fuse and may resume the operation of the circuit. Third, the MOV gets permanently short and the fuse blows off In this case the equipment will not work even if the fuse is replaced and the user will not be able to determine the fault unless an engineer using sophisticated instruments detects that the MOV has shorted and replaces it. Further, since very often than not, the MOVs are provided on PCB along with the equipments and are part of the equipment enclosures it is difficult to replace them. Fourth, when the MOV gets blown off due to the surge. This is a high-risk situation since normally a user or even an engineer with normally available detecting devices will not be able to detect if the MOV has blown off Since, in this case, on replacing the fuse, the equipment starts working without the MOV protection, therefore the equipment is subjected to the danger of damage due to any subsequent surge that might hit the equipment.
Normally, the third and fourth cases are often expected since a very high current flows through the protecting devices during supply variations. In both of these situations the major problem is to determine the functional state of the MOV by the user or an engineer.
Therefore, it is observed that there is a need of a method and device that can enable the user to replace the protecting device without requiring any assistance from the expert of the field and without sacrificing any protection measure for the equipment and, eliminating any probability of the damage to the equipment due to the protection lapse.
Object and Summary of the Invention
It is therefore an object of the invention to obiviate above and other drawbacks from the existing art.
It is another object of the invention to provide a replaceable protecting device that eliminates any probability of damage to the equipment due to the protection lapse.
It is yet another object of the invention to provide a replaceable MOV fuse that eliminates any chances of damage to the equipment due to MOV fault or failure.
It is a further an object of the invention to provide a MOV fuse that enables user to replace the protecting device without requiring any assistance from the expert of the field and without sacrificing any protection measure for the equipment.
It is yet a further object of the invention to cut down on the maintenance cost and time.
It is still another object of the invention to provide a device that eliminates any chance of lapses in repair.
To achieve the above and other objects, the present invention provides 1. A replaceable protective device for electrical equipments, comprising :
a first protecting element connected in series with the supply terminal and the
electrical equipment.
a second protecting element connected after the said first protecting element in
parallel to the said electrical equipment.
the arrangement between said first protecting element and second protecting element
being such that the first protecting element is disabled when either a current more
than threshold current flows through it, or when the supply voltage across the second
protecting element exceeds its threshold voltage.
The first protecting element of the replaceable protecting device could be a fuse wire or semiconductor fuse. The second protecting element of the replaceable protecting device is a Metal Oxide Varistor (MOV) or a semiconductor switch or gas filled switch and the replaceable assembly is any assembly including a Printed Circuit Board (PCB) having connector for connecting it to the supply terminals or load with a replaceable flexibility.
The semiconductor switch can be any semiconductor switch including a transistor having its conducting terminals connected across the said supply terminals and its control terminals connected to a biasing circuit for enabling the transistor only when more than a predetermined tlireshold voltage is detected across supply terminals. The predetermined threshold current/voltage are the highest current/voltage at which the load operates normally.
The replaceable protecting device of the invention is optionally provided with a light and/or sound indicator connected across the first protecting element or second protecting element or both first and second protecting elements for indicating normal operation and/or failure of the protecting device.
The replaceable protecting device is provided with various types of electrical sockets and/or adapters and/or plugs and/or connectors which can be any socket and/or adapter and/or plug and/or any connector including power sockets and/or the type of sockets used with Switched Mode Power Supplies (SMPS) and adapters including pin type and/or serial/parallel type of adapters and any connectors including serial/parallel type of connectors.
Further the replaceable protecting device can be provided at the electrical and/or telecommunication towers and/or high rising buildings for protecting them fi-om lightening.
Brief Description of the Drawings:
The invention will now be described referring to the accompanying drawings.
Figure 1 shows a basic replaceable protecting device for electrical equipments in a
replaceable assembly according to the present invention.
Figure 2 shows another embodiment of replaceable protecting device for electrical
equipments in a replaceable assembly according to the present invention having audible indicator.
Figure3 shows another embodiment of replaceable protecting device for electrical
equipments in a replaceable assembly according to the present invention having a visible indicator.
Figure 4 shows another embodiment possible connecting visible indicators to a replaceable
protecting device for electrical equipments in a replaceable assembly according to the present invention.
Figure 5 shows an embodiment of a replaceable protecting device for electrical equipments
in a replaceable assembly according to the present invention having both audible and visible indicators.
Figure 6 shows another possible embodiment for connecting both visible and audible
indicators to a replaceable protecting device for electrical equipments in a replaceable assembly according to the present invention.
Figure 7 shows current sensitive protection elements.
Figure 8 shows voltage sensitive protection elements.
Figure 9 shows an explicit example of present invention having a current sensitive element
as a fuse and a voltage sensitive element as an MOV.
Figure 10 shows a PCB mounted protecting device.
Figure 11 and Figure 12 shows a socket mounted protecting device according to present invention.
Figure 13 and figure 14 shows an embodiment according to present invention having the protecting device in adapters.
Figure 15 shows a plug mounted protecting device in accordance with the present invention.
Figure 16 and Figure 17 show serial type of adapter and connector used in Telephone / Computer wide area network or local area networks.
Figure 18 shows a multi-pin parallel type of a connector used in Telephone/Computer wide area network or local area networks.
Detailed Description of the Drawings:
The following description is provided in conjunction with the accompanying figures, which are to be fully considered as part of this disclosure. The invention herein is being elaborated mainly referring to the protecting device having MOV-fixse protecting element, however a person skilled in the art will appreciate that the concept of the invention can be easily be applied to other types of protecting elements and a similarly elaborated description is possible for these embodiments. Following description is illustrative only and in no way limited to described example, the invention can be exercised in different shapes, sizes and ratings, and can be used with variety of electrical equipments without departing from the basic concept of the invention any such embodiment will also fall under the scope of the invention.
To obviate drawbacks associated with the prior art and to protect the equipment, present invention provides replaceable protection device that can come in different shapes, sizes and ratings, and can be used with variety of electrical equipments. According to the present invention a replaceable protecting capsule is provided, the protecting capsule is such that it can be entirely replaced whenever a fault is observed. The protecting device of the invention, shown in figure 1, normally comprises a current sensitive protecting elements which can be a fuse or any such protecting element and voltage sensitive protecting elements such as MOV which are very important and desirable protecting elements with the electrical equipments but normally are either difficult to test for the fault in them or difficult to isolate and replace from the electrical equipment. Whenever a high voltage surge hits the electrical equipment the voltage sensitive protecting element acts as short and allows a high current to flow through the current sensitive
element, due to which the current sensitive element disables itself, and in the process the voltage sensitive element may or may not get damaged. The entire protecting device can then be replaced conveniently by any person with ordinary skills and resume normal operation of the equipment without risking the equipment and without requiring any additional expenses towards an expert's assistance. Figure 1 shows a basic replaceable protecting device for electrical equipments in a replaceable assembly according to the present invention.
Figure 2 shows another embodiment of a replaceable protecting device for electrical equipments in a replaceable assembly according to the present invention having an audible indicator.
The device of the invention can further be provided with an indicator that has one or more light emitting e lements for indicating normal operation or fault occurrence. Figure 3 and figure 4 shows embodiment of the present invention having a visible indicator.
Optionally the invention can be provided with both audible and visible indicators as shown in Figure 5 and figure 6.
Figure 7 and Figure 8 show the current and voltage sensitive elements respectively that can be used for the purpose of practicing invention. The current sensitive elements can be any current sensitive element including a fuse wire and/or a semiconductor fuse. Further voltage sensitive elements can be any element including MOVs, semiconductor switches and/or gas discharge tubes etc. according to the current and/or voltage ratings of the electrical equipment for which the protecting device will be used.
Figure 9 shows an explicit example of the present invention having a current sensitive element as a fuse and a voltage sensitive element as an MOV. According to the invention the fuse wire of the desired rating is connected in series with the first terminal of the mains and the other end of the fuse is connected to the load and to the MOV. The second terminal of the load and MOV are connected to the second terminal of the mains. A buzzer is connected across the ftise through a high value resistance Rl and a diode D for indicating normal/abnormal operation of the MOV.
the operation of the circuit can be understood as follows. When a high voltage surge hits the electrical equipment, the MOV that normally has high impedance, w ould behave like a short, thereby allowing a high current to flow through the fuse and blowing it hence protecting the electrical equipment. In the process the MOV is likely to get damaged itself and would, therefore, be of no benefit in the case of a future surge/spike. Whenever a fuse blows off the protecting capsule of the invention indicates the same by a visual indicator as well as a buzzer. In such situation no matter whether the MOV is intact or not the entire protecting capsule can be replaced which is simple and any layman can do so without requiring skills of the art.
The replaceable protecting device can be designed and provided with any type of load according to its power driving capacities. Other than the electrical equipments this device can be built into the plugs, adapters, sockets, connectors etc. Without limiting the scope of the invention some of the possible products are described below.
Further for the low voltage applications e.g. electronic circuit boards used in various electronic equipment like television, telephone, computers, washing machines etc a semiconductor switch can replace the MOV. The semiconductor switch can be designed according to operating specification of the electronic equipment one of the possible semiconductor switches is shown in figure 8.
One particular low voltage application is possible in the high rise buildings, electrical or telecommunication towers wherein a low voltage equipment which are normally sealed waterproof equipments like an aviation obstruction light etc. are placed on top of a building or tower and is connected with long cables to the power supply at base of the tower or building. Such electrical equipments are subjected to high risk of the damage due to lightening strikes. For these equipments it is highly desirable that a replaceable protecting device is provided outside the equipment enclosure.
Figure 10 shows a PCB mounted protecting device. In this configuration the protecting device mounted on a replaceable plug-in type PCB, which can be plugged into another PCB. The PCB or a capsule will have a male or female connector capable of providing electrical paths. This fuse
f, inserted into the main equipments PCB that has a corresponding connector for Phase or Line Input L(Input), a common Neutral N and a Phase or Line output L(Output). In the event of a surge/spike the entire protecting device is replaced.
Figure 11 and Figure 12 shows a socket mounted protecting device according to the present invention. The MOV fuse can also be mounted inside 2 pin/3 pin or Switched Mode Power Supply (SMPS) sockets. In this configuration the protecting device is made in the form of a capsule, which is motmted on the back of an electrical socket. The input of the protecting device is connected to the socket with screws or by jacks. The phase wire from electrical mains is connected to the terminal L (Input). Further the second terminal N of the protecting device is mounted on the leg of the socket where the electrical neutral is connected and the terminal marked L (Output) is mounted on the leg of the socket where from the phase or live wire is to be made available to the plug of the equipment.
Figure 13 and figure 14 shows an embodiment according to present invention having protecting device in adapters. In this configuration a protecting device is made in the form of a capsule, which is sandwiched between the two parts of a 2 pin/3 pin multi-plug adaptor. The terminal marked L (Input) is fixed to the leg of the adapter, which is to go into the socket connected to the electrical mains. A wire originating from the junction of the leg of the adapter which is on the one hand to go into the socket connected to the electrical mains and on the other connected to the socket of the adapter where it will connect with the plug of the appliance is fixed to the terminal on the fuse marked as N. The terminal on the fuse marked L(Output) is fixed to the socket of the adapter where it will connect with the plug of the appliance. Metal strips/ wires may be used to connect the capsule to the legs/socket pins, as per convenience. The voltage and current rating of the protecting elements of the protecting device can be chosen according to the type of appliances. The protecting device can be replaced easily in the event of a surge or spike. Models where the adapter will not have to be opened for replacing the fuse and where the capsule will be pushed in and pulled out can be made depending on economics.
Figure 15 shows a plug mounted protecting device in accordance with the present invention. The protecting device of the invention is provided in a disposable cartridge with the normal 3 pin/2
In plugs. In this configuration the protecting device is sandwiched between the two parts of a plug top. the supply and the load terminals are connected in a manner discussed earlier for adapters.
Figure 16 and Figure 17 shows serial type of adapter and connector used in Telephone/Computer wide area network or local area networks. In this configuration, the protecting device is connected between the input and output terminals as shown in the figure.
Figure 18 shows a multi-pin parallel type of a connector used in Telephone/Computer wide area network or local area networks. For such applications with each line a protecting device is provided.
Without departing from the scope of the invention many other configurations and applications are possible for exercising the present invention which are obvious to a person skilled in the art. Any such configuration which might not have been described herein will fall under the scope of the invention and is protected.
Advantages of the invention:
a. Costly equipment will be properly protected from high voltage surges.
b. Fuses/MOVs of proper ratings will be used.
c. Audio and visual indicators/alarms can be connected indicate the condition of fuse.
d. It can even be fitted in existing equipment where MOV may or may not be working.
e. No trained engineer/technician is necessary to rectify the problem.
f. The down time of the equipment can be drastically reduced.





We Claims :-
1. A replaceable protective device for electrical equipments, comprising :
- a first protecting element connected in series with the supply terminal and the
electrical equipment.
- a second protecting element connected after the said first protecting e lement in
parallel to the said electrical equipment.
- the arrangement between said first protecting element and second protecting
element being such that the first protecting element is disabled when either a
current more than threshold current flows through it, or when the supply voltage
across the second protecting element exceeds its threshold voltage.
2. The replaceable protective device for electrical equipments as claimed in claim 1 wherein the said first protecting element is a fuse wire.
3. The replaceable protective device for electrical equipments as claimed in claim 1 wherein the said first protecting element is a semiconductor fiise or device.
4. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said second protecting element is a Metal Oxide Varistor (MOV).
5. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said second protecting element is a semiconductor switch.
6. The replaceable protective device for electrical equipments as claimed in claim 5 wherein said semiconductor switch is a transistor.
7. The replaceable protective device for electrical equipments as claimed in claim 6 wherein said transistor has its conducting terminals connected across the said load or supply terminals and its control terminals connected to a biasing circuit for enabling the
transistor only when more than a threshold voltage is detected across the load or supply terminals.
8. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said second protecting element is a gas filled switch.
9. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said protecting device is provided with a light and/or sound indicator for indicating normal operation and/or when the protecting device needs replacement.
10. The replaceable protective device for electrical equipments as claimed in claim 9 wherein said light and/or sound indicator is connected across first protecting element and/or second protecting element and/or both first and second protecting elements.
11. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said replaceable assembly is any assembly including a Printed Circuit Board (PCB) having socket for connecting it to load.
12. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said protecting device is provided within the electrical sockets and/or adapters and/or plugs and/or any connectors.
13. The replaceable protective device for electrical equipments as claimed in claim 12 wherein said electrical sockets are any sockets including power sockets.
14. The replaceable protective device for electrical equipments as claimed in claim 12 wherein said electrical adapters are any adapters including pin type and/or serial/parallel type of adapters
15. The replaceable protective device for electrical equipments as claimed in claim 12 wherein said electrical connectors are any connectors including serial/parallel type of connectors.
16. The replaceable protective device for electrical equipments as claimed in claim 1 wherein said protective device is provided at the electrical and/or telecommunication towers and/or high rising buildings for protecting them from lightening.
17. The replaceable protective device for electrical equipments as herein described with reference to the accompanying drawings.



Documents:

1493-del-2004-abstract.pdf

1493-del-2004-claims.pdf

1493-DEL-2004-Correspondence Others-(01-12-2011)..pdf

1493-DEL-2004-Correspondence-Others-(08-10-2010).pdf

1493-del-2004-correspondence-others.pdf

1493-del-2004-description (complete).pdf

1493-del-2004-drwings.pdf

1493-DEL-2004-Form-1-(01-12-2011).pdf

1493-del-2004-form-1.pdf

1493-del-2004-form-19.pdf

1493-del-2004-form-2.pdf

1493-del-2004-form-3.pdf

1493-del-2004-gpa.pdf

1493-DELNP-2004-Correspondence Others-(01-12-2011).pdf

1493-DELNP-2004-GPA-(01-12-2011).pdf


Patent Number 247445
Indian Patent Application Number 1493/DEL/2004
PG Journal Number 15/2011
Publication Date 15-Apr-2011
Grant Date 07-Apr-2011
Date of Filing 11-Aug-2004
Name of Patentee HIMANGSHU RAI VAISH, an Indian national
Applicant Address S-19, PANCHSHILA PARK, NEW DELHI-110017, INDIA.
Inventors:
# Inventor's Name Inventor's Address
1 HIMANGSHU RAI VAISH S-19, PANCHSHILA PARK, NEW DELHI-110017, INDIA.
PCT International Classification Number H02H 9/06
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA