The present invention relates to a lamp socket for light strings having lights arranged in series. More particularly, the invention relates to a semiconductor chip container with chip therein for use in a light socket forming a shunt to allow for electricity to continually conduct throughout the light string keeping the remainder of the lights lit when one or more lights on the string burn out, become dysfunctional or are removed from a socket.
Decorative light strings which are connected in series are highly popular in the United States, especially during holidays in November and December. A drawback with such light strings is that they commonly include of a plurality of individual light units with bulbs which are electrically connected in series and not in parallel. The bulbs are typically incandescent bulbs having a filament formed between two leads of the bulb, the filament giving off light when a current is passed from one lead to the other, through the filament. As the bulb is used, over time, the filament will burn out, breaking the series circuit in which the bulb is arranged. This will cause the entire light string to go out unless a backup circuit path is available to bypass the failed filament.
Presently, inside of the mini-light bulb, there is a backup circuit path having a shunt system arranged in parallel with the filament of each bulb. This shunt is comprised of three turns of aluminum wire with an insulating (oxide) coating. When the filament is intact, current passes through the filament because the resistance of the filament is low compared to that of the insulating material on the shunt. However, when the filament burns out, the voltage across the leads of the bulb increases to the full line potential of 120 volts AC. The actual peak voltage at 120 volts AC is approximately 170 volts. The insulating coating on the shunt wire is designed to break down at a minimum of 40 volts to provide a backup circuit path around the failed filament. However, this ‘shorting’ mechanism only works about 70% of the time. When it fails to operate, the entire series-wired light string goes out.
One solution that allows the circuit to continue to function when there is a failure as described above is taught in U.S. Pat. Nos. 6,084,357 and 6,580,182 which is issued to the same inventor herein. The solution is to provide a backup circuit path having a semiconductor shunt system arranged in parallel with the filament of each bulb. As described in the above mentioned issued patents, the semiconductor device might be a diode array or back-to-back Zener diodes. In this manner, even if a bulb burns out, breaks, or falls out of its socket, the rest of the light units in the light string remain on because the series circuit remains closed. The system employed in the above issued patents is the shunting of each light bulb in the string with such a semiconductor shunt mounted in a package as the standard DO-41 package. The DO-41 package housing the semiconductor chip is placed inside of each socket and is electrically connected to the light bulb's conductive connection in the socket.
In addition, co-pending U.S. application Ser. No. 10/611,744 described a further improvement in wherein a shunt device included a semiconductor chip held in place by a spring-like conductive member. While this improvement has met with success, the shunt device is difficult to work with due to the diode chip size being extremely small (i.e., chip size is 0.028″×0.028″) and current implementation is relatively expensive.
While the functionality of decorative light strings using the inventor's prior shunt devices work well, there remains a need to improve the shunt device as set forth herein and reduce the cost of producing the decorative light string.
It is an object to improve decorative light strings.
It is another object to reduce the cost of decorative light strings.
It is a further object to provide a semiconductor chip operably disposed within a container inside of a light socket.
Accordingly, an embodiment of the present invention is directed to a shunt device for use in a light socket having a semiconductor chip operably disposed within a container having an open surface through which the semiconductor chip is exposed and held in place by a conductive member which contacts the chip through the open surface. Another embodiment provides for the container and chip to be held in place by conductive leads having ends which plug into electric terminals of the socket. Still another embodiment is directed to a pair of bent conductive members having the container and chip held therebetween. In yet another embodiment, the conductive members can be modified to include retention fingers which are opposing each other in a spaced relationship in a manner to form a retaining seat for the container and chip which can be preferably held therebetween. Still another embodiment provides for a chip and container to be directly connected to each conductive terminal and have a conductive wire interconnecting the two chips, wherein each chip is intended to dissipate half of the power keeping the socket from overheating in cases where too much current is drawn, such as when higher watt light bulbs are used.
The light socket of the instant invention is for use with a light string having at least two light sockets connected in series via wire segments having associated contact elements. A light bulb is receivable by each socket and can be removed and replaced when a filament of the bulb burns out.
Other objects will be revealed by the following description and drawings.
a is a blow up of a part of
a is a blow up of a part of
Referring now to the drawings, the semiconductor chip of the present invention is generally designated by the numeral 10. The semiconductor chip 10 is a relatively flat and thin plate which is of the type described in co-pending application Ser. No. 10/611,744. The chip 10 is used in various embodiments described herein. The chip 10 is very small having a size of about 0.028″×0.028″. The handling of this chip 10 is difficult from an integration and cost standpoint into a socket 12.
Accordingly, the improvement in present invention provides a container 1000 made of a nonconductive material such as plastic. The container 1000 can include a pair of interconnectable members 1002 and 1004 which are here shown by way of example to be rectangular, but it is recognized that other shapes can be employed. Members 1002 and 1004 can be of a dimensional size of about 0.20″×0.20″ for ease of insertion. The member 1002 includes tab retention surface 1006 which extends inwardly from a mating surface 1008 and tab 1100 which extends outwardly from the mating surface 1008. Likewise, member 1004 includes tab retention surface 1012 which extends inwardly from a mating surface 1014 and tab 1016 which extends outwardly from the mating surface 1014. The members 1002 and 1004 can be mated such that the tabs 1010 and 1016 are of a size, configuration and orientation to be received within the respective tab retention surfaces 1012 and 1006 in a friction fit manner to retain the members 1002 and 1004 together. In addition, a chip receiving surface 1018 extends inwardly from mating surface 1008 and a chip exposing surface 1020 extends inwardly from an outer surface 1022 terminating into a shoulder surface 1024 which connects to the chip receiving surface 1018. Likewise, a chip receiving surface 1026 extends inwardly from mating surface 1014 and a chip exposing surface 1028 extends inwardly from an outer surface 1030 terminating into a shoulder surface 1032 which connects to the chip receiving surface 1026. The chip receiving surfaces 1018 and 1026 are slightly larger than the dimensions of the chip 10. The mating surfaces 1008 and 1014 can preferably be generally planar and flat to provide for a mating connection without a gap therebetween, save for the described receiving surfaces 1018 and 1026. Prior connecting the members 1002 and 1004, the chip 10 is disposed in chip receiving surface 1018, for example, to rest on shoulder surface 1024. Then, the member 1004 is mated with member 1002 as described to secure the chip in a retained manner within the receiving surfaces 1018 and 1026.
In yet another embodiment,
Still another embodiment shown in
By way of example, a bottom surface 1034 of the socket 12 shown in
The above described embodiments are set forth by way of example and are not for the purpose of limiting the present invention. It will be readily apparent to those skilled in the art that obvious modifications, derivations and variations can be made to the embodiments without departing from the scope of the invention. Accordingly, the claims appended hereto should be read in their full scope including any such modifications, derivations and variations.
This is a continuation-in-part of application U.S. Ser. No. 10/611,744 filed Jul. 1, 2003 now U.S. Pat. No. 6,929,383.
Number | Name | Date | Kind |
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2072337 | Kamm | Mar 1937 | A |
3345482 | Lou | Oct 1967 | A |
4727449 | Fleck | Feb 1988 | A |
4769579 | Jou | Sep 1988 | A |
4922155 | Morris et al. | May 1990 | A |
5442258 | Shibata | Aug 1995 | A |
6084357 | Janning | Jul 2000 | A |
6580182 | Janning | Jun 2003 | B2 |
6713971 | Wong | Mar 2004 | B1 |
Number | Date | Country | |
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20050258777 A1 | Nov 2005 | US |
Number | Date | Country | |
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Parent | 10611744 | Jul 2003 | US |
Child | 10908365 | US |