US2484596A - Lamp socket for series lighting circuits - Google Patents
Lamp socket for series lighting circuits Download PDFInfo
- Publication number
- US2484596A US2484596A US776607A US77660747A US2484596A US 2484596 A US2484596 A US 2484596A US 776607 A US776607 A US 776607A US 77660747 A US77660747 A US 77660747A US 2484596 A US2484596 A US 2484596A
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- US
- United States
- Prior art keywords
- disc
- lamp
- resistance
- shell
- contact
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R33/00—Coupling devices specially adapted for supporting apparatus and having one part acting as a holder providing support and electrical connection via a counterpart which is structurally associated with the apparatus, e.g. lamp holders; Separate parts thereof
- H01R33/945—Holders with built-in electrical component
- H01R33/95—Holders with built-in electrical component with fuse; with thermal switch
Definitions
- This inventionv relates to lamp sockets and more particularly to sockets for use in series-lighting circuits.
- the object of thisinvention is to automatically shunt an inoperative series-connectedlamp on thefailure of said lamp.
- numerous means have been vSuggested and, employed to maintain the operation of a series-lighting circuit, notwithstanding a failure of one or more of the lamps. Broadly classed, these means have included mechanical shunts both automatically and manually operated, and electrical shunts operated by the rupturing of an insulating lm, by placing a high resistance across the lower resistance of the filament, or by connecting a semiconductor having a negative temperature coefficient of resistance across the lamp.
- an improved structure for shunting a series-connected lamp which has failed by utilizing a material having a negative temperature coefficient oi resistance and associating it with a shell for a socket in a manner such that a very satisfactory lamp socket is realized which is compact, simple and easily manufactured.
- this invention comprises a lamp socket for a series-lighting circuit, for example, a series-lighting circuit for a Christmas tree, having a centrally apertured disc of material having a negative coeiiicient of resistance secured in the bottom of the shell forming a mechanical support for the lamp.
- the central contact of the lamp passes through a central aperture in the disc thereby permanently shunting the disc across the lamp lament.
- Fig. 1 discloses in the main a sectional view of a socket illustrative of one embodiment of this invention
- Fig. 2 is a detailed plan View of the socket of Fig. 1.
- the drawings show a lamp socket of the conventional typev having an outer casing I of insulating material in which a threaded shell contact I I containing a central contact I2 is suitably secured.
- Leads I3 and I4 are connected to the shell contact Il and the central contact I2, respectively, to complete the circuit from the source through the leads I3 and I4, the contacts II and I2 and a lamp L mounted in the socket.
- Secured within the bottom of the shell contact II in a September 27, 1947; Serial No. 775,697 J3 cisnes.- 01; 2er-449i suitable manner, such as by spinning or lcrimpin in its lower edge 'I5 is a centrally apertured disc I6 of a material having a high negative tempera@ ture coefficient of resistance.
- a suitable material for this disc is that disclosed in Patent 2,258; l(546 to Grisclale of October 14, 1941.
- This disc .I6 structurally replaces the nber or ceramic insulating-ldisc which is usuallymounted inthe shell contact of an ordinary socket to support the central contact, and simultaneously provides a shunt between the shell contact II and the central contact I2 across the filament of the lamp.
- the outer and inner peripheries have coverings or electrodes I1 and I8 (shown with an exaggerated thickness for purposes of clarity) deposited thereon, thus providing metal-to-metal contacts between these members.
- This socket may be employed in a series circuit. for example, a Christmas tree lighting circuit having a plurality of lamps. W'hen connected in a circuit of this nature with an operative lamp secured in the socket, the resistance of the material of the disc I6 is such that the resistance between the contact II and the contact I2 across the disc is, relative t0 the lamp lament, effectively an open circuit, and the disc performs only the mechanical function of supporting the central contact I2. However on rupture of the circuit through the lamp an increased electromotive force is impressed across the disc causing an increase in the normally minute current flowing therethrough.
- the increased current flow increases the rate of heat generation within the disc such that it ls greater than the heat dissipated and thus the thermal unbalance causes an increase in the temperature and a corresponding decrease of the resistance of the disc to a point limited by the resistance of the circuit where the resistance of the disc again stabilizes.
- This second stable resistance value is approximately equal to the resistance of the parallel lamp and disc which it has replaced, thus restoring the normal operation of the remainder of the circuit, the value being determined in the well-known manner by the selection of a material having the desired negative temperature coeflicient of resistance and a structure having the desired thermal, electrical and mechanical characteristics.
- said disc having an aperture at its center, a contact in said aperture
- the-aperture a contact member spaced from said shell, a shunt connected between said shell and said contact, said shunt comprising a disc of material having a high negative temperature coetlicient of resis tance permanently secured in an end of said shell and supporting said contact member in spaced relationship to said shellseparate metallic coatings on said disc engaging saidzcontactand said shell respectively, and a pair of leading-in conductors for supplying energy to said socket, one
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- Connecting Device With Holders (AREA)
Description
Oct. 1l, 1949. M. c. wALTz LAMP SOCKET FOR SERIES LIGHTING CIRCUITS Filed Sept. 27, 1947 /N VEA/TOR M. C .W4 L TZ Patented Oct. 11, Y1949 'ffUNTED,,STATE Maynard o. Wal-tz,
Maplewood, assigner-tto Bell Telephone Laboratories, Incorporated, New
York, N. Y., a corporation of New Yorkv r v Application This inventionv relates to lamp sockets and more particularly to sockets for use in series-lighting circuits.
The object of thisinventionis to automatically shunt an inoperative series-connectedlamp on thefailure of said lamp. ,ff'Heretofore numerous means have been vSuggested and, employed to maintain the operation of a series-lighting circuit, notwithstanding a failure of one or more of the lamps. Broadly classed, these means have included mechanical shunts both automatically and manually operated, and electrical shunts operated by the rupturing of an insulating lm, by placing a high resistance across the lower resistance of the filament, or by connecting a semiconductor having a negative temperature coefficient of resistance across the lamp.
In accordance with this invention an improved structure is provided for shunting a series-connected lamp which has failed by utilizing a material having a negative temperature coefficient oi resistance and associating it with a shell for a socket in a manner such that a very satisfactory lamp socket is realized which is compact, simple and easily manufactured.
More particularly this invention comprises a lamp socket for a series-lighting circuit, for example, a series-lighting circuit for a Christmas tree, having a centrally apertured disc of material having a negative coeiiicient of resistance secured in the bottom of the shell forming a mechanical support for the lamp. The central contact of the lamp passes through a central aperture in the disc thereby permanently shunting the disc across the lamp lament.
The various features of this invention will be better understood from the following detailed description when considered in conjunction with the accompanying drawings in which:
Fig. 1 discloses in the main a sectional view of a socket illustrative of one embodiment of this invention, and
Fig. 2 is a detailed plan View of the socket of Fig. 1.
The drawings show a lamp socket of the conventional typev having an outer casing I of insulating material in which a threaded shell contact I I containing a central contact I2 is suitably secured. Leads I3 and I4 are connected to the shell contact Il and the central contact I2, respectively, to complete the circuit from the source through the leads I3 and I4, the contacts II and I2 and a lamp L mounted in the socket. Secured within the bottom of the shell contact II in a September 27, 1947; Serial No. 775,697 J3 cisnes.- 01; 2er-449i suitable manner, such as by spinning or lcrimpin in its lower edge 'I5 is a centrally apertured disc I6 of a material having a high negative tempera@ ture coefficient of resistance. A suitable material for this disc is that disclosed in Patent 2,258; l(546 to Grisclale of October 14, 1941. This disc .I6 structurally replaces the nber or ceramic insulating-ldisc which is usuallymounted inthe shell contact of an ordinary socket to support the central contact, and simultaneously provides a shunt between the shell contact II and the central contact I2 across the filament of the lamp. In order to insure adequate electrical contacts having constant resistances between the shell contact Il and the disc I6 and between the central contact I2 and the disc I6 the outer and inner peripheries have coverings or electrodes I1 and I8 (shown with an exaggerated thickness for purposes of clarity) deposited thereon, thus providing metal-to-metal contacts between these members.
This socket may be employed in a series circuit. for example, a Christmas tree lighting circuit having a plurality of lamps. W'hen connected in a circuit of this nature with an operative lamp secured in the socket, the resistance of the material of the disc I6 is such that the resistance between the contact II and the contact I2 across the disc is, relative t0 the lamp lament, effectively an open circuit, and the disc performs only the mechanical function of supporting the central contact I2. However on rupture of the circuit through the lamp an increased electromotive force is impressed across the disc causing an increase in the normally minute current flowing therethrough. The increased current flow increases the rate of heat generation within the disc such that it ls greater than the heat dissipated and thus the thermal unbalance causes an increase in the temperature and a corresponding decrease of the resistance of the disc to a point limited by the resistance of the circuit where the resistance of the disc again stabilizes. This second stable resistance value is approximately equal to the resistance of the parallel lamp and disc which it has replaced, thus restoring the normal operation of the remainder of the circuit, the value being determined in the well-known manner by the selection of a material having the desired negative temperature coeflicient of resistance and a structure having the desired thermal, electrical and mechanical characteristics.
As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter herelnbefore set forth, or shown in the accompanying draW- ings, is to be interpreted as illustrative and not in a limiting sense.
What is claimed is:
1. A lamp socket Comprising an electrically conductive shell having twoy open= ends, the opening in one of said ends being smaller than the opening in the other of said ends, a disc of resistance material having a negative temperature coem cient of resistance inalterablyv secured in the,
smaller opening of said shell, said disc havingan aperture at its center, a contact in said aperture,
and separate metallic coatings on. the-aperture a contact member spaced from said shell, a shunt connected between said shell and said contact, said shunt comprising a disc of material having a high negative temperature coetlicient of resis tance permanently secured in an end of said shell and supporting said contact member in spaced relationship to said shellseparate metallic coatings on said disc engaging saidzcontactand said shell respectively, and a pair of leading-in conductors for supplying energy to said socket, one
conductor being connected to said shell and the other conductor being xedly and directly connected to said contact member.
MAYNARD C. WALTZ.
REFERENCES CITED The following references are of record in the me of'this patent:
UNITED. STATES PATENTS Number Name Dots 1,536,332 Dam May, ma 1,641,564 Zierdt Sept; 6, 1927 1,941,984 Gustin. et al 1. Jan. 2, 1934 1,950,028 Gustin .Mar.,6', 1934 1,954,355 Handy: Apr. 10, 1934 2,258,646 Grisdale. Oct. 14, 1941
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US776607A US2484596A (en) | 1947-09-27 | 1947-09-27 | Lamp socket for series lighting circuits |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US776607A US2484596A (en) | 1947-09-27 | 1947-09-27 | Lamp socket for series lighting circuits |
Publications (1)
Publication Number | Publication Date |
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US2484596A true US2484596A (en) | 1949-10-11 |
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ID=25107886
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US776607A Expired - Lifetime US2484596A (en) | 1947-09-27 | 1947-09-27 | Lamp socket for series lighting circuits |
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US (1) | US2484596A (en) |
Cited By (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3317907A (en) * | 1964-01-22 | 1967-05-02 | Gen Electric | Indicating lamp housing |
US3818263A (en) * | 1972-05-05 | 1974-06-18 | W Belko | Electronic component |
US4544861A (en) * | 1983-04-11 | 1985-10-01 | Certified Energy Systems, Inc. | Rectifier housing for use with light bulbs |
US5453664A (en) * | 1994-02-01 | 1995-09-26 | Harris; Geoffrey H. | Light string with improved shunt system |
US6323597B1 (en) * | 2000-05-15 | 2001-11-27 | Jlj, Inc. | Thermistor shunt for series wired light string |
US7253556B1 (en) | 2006-12-08 | 2007-08-07 | Tech Patent Licensing, Llc | Light string socket with mechanical shunt |
US7453194B1 (en) | 2008-06-05 | 2008-11-18 | Gibboney James W | Mechanical shunt for use in the sockets of a string of lights |
US20090039794A1 (en) * | 1995-06-26 | 2009-02-12 | Janning John L | Miniature light bulb for random high-low twinkle in series-wired light string |
US7554266B1 (en) | 2007-09-11 | 2009-06-30 | Willis Electric Co., Ltd. | Mechanical shunt for use in a socket in a string of lights |
US20100003891A1 (en) * | 2007-12-06 | 2010-01-07 | Willis Electric Co., Ltd. | Three dimensional displays having deformable constructions |
US20100045186A1 (en) * | 2006-10-04 | 2010-02-25 | Janning John L | Dual brightness twinkle in a miniature light bulb |
US20100061025A1 (en) * | 2008-09-09 | 2010-03-11 | Parker Francis J | LED module for sign channel letters and driving circuit |
US20100289415A1 (en) * | 2009-05-18 | 2010-11-18 | Johnny Chen | Energy efficient decorative lighting |
US20110085327A1 (en) * | 2009-10-14 | 2011-04-14 | Johnny Chen | Decorative light display with LEDs |
US9055777B2 (en) | 2010-09-23 | 2015-06-16 | Willis Electric Co., Ltd. | Modular artificial lighted tree with decorative light string |
US9157587B2 (en) | 2011-11-14 | 2015-10-13 | Willis Electric Co., Ltd. | Conformal power adapter for lighted artificial tree |
US9179793B2 (en) | 2012-05-08 | 2015-11-10 | Willis Electric Co., Ltd. | Modular tree with rotation-lock electrical connectors |
US9222656B2 (en) | 2011-11-14 | 2015-12-29 | Willis Electric Co., Ltd. | Conformal power adapter for lighted artificial tree |
US9220361B1 (en) | 2013-12-03 | 2015-12-29 | Willis Electric Co., Ltd. | Dual-voltage lighted artificial tree |
US9441823B1 (en) | 2011-12-09 | 2016-09-13 | Willis Electric Co., Ltd. | Modular lighted artificial tree |
US9439528B2 (en) | 2013-03-13 | 2016-09-13 | Willis Electric Co., Ltd. | Modular tree with locking trunk and locking electrical connectors |
US9572446B2 (en) | 2012-05-08 | 2017-02-21 | Willis Electric Co., Ltd. | Modular tree with locking trunk and locking electrical connectors |
US9671074B2 (en) | 2013-03-13 | 2017-06-06 | Willis Electric Co., Ltd. | Modular tree with trunk connectors |
US9883566B1 (en) | 2014-05-01 | 2018-01-30 | Willis Electric Co., Ltd. | Control of modular lighted artificial trees |
US9883706B2 (en) | 2011-05-20 | 2018-02-06 | Willis Electric Co., Ltd. | Multi-positional, locking artificial tree trunk |
US9894949B1 (en) | 2013-11-27 | 2018-02-20 | Willis Electric Co., Ltd. | Lighted artificial tree with improved electrical connections |
US10010208B2 (en) | 2012-05-08 | 2018-07-03 | Willis Electric Co., Ltd. | Modular tree with electrical connector |
US10206530B2 (en) | 2012-05-08 | 2019-02-19 | Willis Electric Co., Ltd. | Modular tree with locking trunk |
US10683974B1 (en) | 2017-12-11 | 2020-06-16 | Willis Electric Co., Ltd. | Decorative lighting control |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1536332A (en) * | 1924-11-22 | 1925-05-05 | Monowatt Electric Imp Co Inc | Lamp socket for christmas-tree lighting |
US1641564A (en) * | 1922-12-14 | 1927-09-06 | Union Switch & Signal Co | Electroresponsive cell |
US1941984A (en) * | 1929-06-18 | 1934-01-02 | Westinghouse Lamp Co | Cut-out for series lamps |
US1950028A (en) * | 1929-08-29 | 1934-03-06 | Westinghouse Lamp Co | Base cut-out |
US1954355A (en) * | 1929-03-20 | 1934-04-10 | Howard F Witherhead | Electric lighting set resistor |
US2258646A (en) * | 1939-05-17 | 1941-10-14 | Bell Telephone Labor Inc | Resistance material |
-
1947
- 1947-09-27 US US776607A patent/US2484596A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1641564A (en) * | 1922-12-14 | 1927-09-06 | Union Switch & Signal Co | Electroresponsive cell |
US1536332A (en) * | 1924-11-22 | 1925-05-05 | Monowatt Electric Imp Co Inc | Lamp socket for christmas-tree lighting |
US1954355A (en) * | 1929-03-20 | 1934-04-10 | Howard F Witherhead | Electric lighting set resistor |
US1941984A (en) * | 1929-06-18 | 1934-01-02 | Westinghouse Lamp Co | Cut-out for series lamps |
US1950028A (en) * | 1929-08-29 | 1934-03-06 | Westinghouse Lamp Co | Base cut-out |
US2258646A (en) * | 1939-05-17 | 1941-10-14 | Bell Telephone Labor Inc | Resistance material |
Cited By (45)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3317907A (en) * | 1964-01-22 | 1967-05-02 | Gen Electric | Indicating lamp housing |
US3818263A (en) * | 1972-05-05 | 1974-06-18 | W Belko | Electronic component |
US4544861A (en) * | 1983-04-11 | 1985-10-01 | Certified Energy Systems, Inc. | Rectifier housing for use with light bulbs |
US5453664A (en) * | 1994-02-01 | 1995-09-26 | Harris; Geoffrey H. | Light string with improved shunt system |
US20090039794A1 (en) * | 1995-06-26 | 2009-02-12 | Janning John L | Miniature light bulb for random high-low twinkle in series-wired light string |
US6323597B1 (en) * | 2000-05-15 | 2001-11-27 | Jlj, Inc. | Thermistor shunt for series wired light string |
US20100045186A1 (en) * | 2006-10-04 | 2010-02-25 | Janning John L | Dual brightness twinkle in a miniature light bulb |
US7253556B1 (en) | 2006-12-08 | 2007-08-07 | Tech Patent Licensing, Llc | Light string socket with mechanical shunt |
US7554266B1 (en) | 2007-09-11 | 2009-06-30 | Willis Electric Co., Ltd. | Mechanical shunt for use in a socket in a string of lights |
US20100003891A1 (en) * | 2007-12-06 | 2010-01-07 | Willis Electric Co., Ltd. | Three dimensional displays having deformable constructions |
US7943211B2 (en) | 2007-12-06 | 2011-05-17 | Willis Electric Co., Ltd. | Three dimensional displays having deformable constructions |
US7453194B1 (en) | 2008-06-05 | 2008-11-18 | Gibboney James W | Mechanical shunt for use in the sockets of a string of lights |
US20100061025A1 (en) * | 2008-09-09 | 2010-03-11 | Parker Francis J | LED module for sign channel letters and driving circuit |
US20110085271A1 (en) * | 2008-09-09 | 2011-04-14 | Inshore Holdings, Llc | LED Modules for Sign Channel Letters and Driving Circuit |
US8305717B2 (en) | 2008-09-09 | 2012-11-06 | Inshore Holdings, Llc | LED modules for sign channel letters and driving circuit |
US8611057B2 (en) | 2008-09-09 | 2013-12-17 | Inshore Holdings, Llc | LED module for sign channel letters and driving circuit |
US20100289415A1 (en) * | 2009-05-18 | 2010-11-18 | Johnny Chen | Energy efficient decorative lighting |
US20110085327A1 (en) * | 2009-10-14 | 2011-04-14 | Johnny Chen | Decorative light display with LEDs |
US9861147B1 (en) | 2010-09-23 | 2018-01-09 | Willis Electric Co., Ltd. | Modular lighted tree |
US9887501B2 (en) | 2010-09-23 | 2018-02-06 | Willis Electric Co., Ltd. | Modular artificial lighted tree with decorative light string |
US9484687B1 (en) | 2010-09-23 | 2016-11-01 | Willis Electric Co., Ltd. | Modular lighted tree |
US10070675B2 (en) | 2010-09-23 | 2018-09-11 | Willis Electric Co., Ltd. | Modular lighted tree with internal electrical connection system |
US9055777B2 (en) | 2010-09-23 | 2015-06-16 | Willis Electric Co., Ltd. | Modular artificial lighted tree with decorative light string |
US9883706B2 (en) | 2011-05-20 | 2018-02-06 | Willis Electric Co., Ltd. | Multi-positional, locking artificial tree trunk |
US9677749B2 (en) | 2011-11-14 | 2017-06-13 | Willis Electric Co., Ltd. | Conformal power adapter for lighted artificial tree |
US9157587B2 (en) | 2011-11-14 | 2015-10-13 | Willis Electric Co., Ltd. | Conformal power adapter for lighted artificial tree |
US9222656B2 (en) | 2011-11-14 | 2015-12-29 | Willis Electric Co., Ltd. | Conformal power adapter for lighted artificial tree |
US9664362B2 (en) | 2011-11-14 | 2017-05-30 | Willis Electric Co., Ltd. | Lighted artificial tree with multi-terminal electrical connectors for power distribution and control |
US9441823B1 (en) | 2011-12-09 | 2016-09-13 | Willis Electric Co., Ltd. | Modular lighted artificial tree |
US9441800B1 (en) | 2011-12-09 | 2016-09-13 | Willis Electric Co., Ltd. | Modular lighted artificial tree |
US9572446B2 (en) | 2012-05-08 | 2017-02-21 | Willis Electric Co., Ltd. | Modular tree with locking trunk and locking electrical connectors |
US9648919B2 (en) | 2012-05-08 | 2017-05-16 | Willis Electric Co., Ltd. | Modular tree with rotation-lock electrical connectors |
US10010208B2 (en) | 2012-05-08 | 2018-07-03 | Willis Electric Co., Ltd. | Modular tree with electrical connector |
US10206530B2 (en) | 2012-05-08 | 2019-02-19 | Willis Electric Co., Ltd. | Modular tree with locking trunk |
US9179793B2 (en) | 2012-05-08 | 2015-11-10 | Willis Electric Co., Ltd. | Modular tree with rotation-lock electrical connectors |
US10098491B2 (en) | 2013-03-13 | 2018-10-16 | Willis Electric Co., Ltd. | Modular tree with locking trunk and locking electrical connectors |
US9671074B2 (en) | 2013-03-13 | 2017-06-06 | Willis Electric Co., Ltd. | Modular tree with trunk connectors |
US9439528B2 (en) | 2013-03-13 | 2016-09-13 | Willis Electric Co., Ltd. | Modular tree with locking trunk and locking electrical connectors |
US9894949B1 (en) | 2013-11-27 | 2018-02-20 | Willis Electric Co., Ltd. | Lighted artificial tree with improved electrical connections |
US9677748B1 (en) | 2013-12-03 | 2017-06-13 | Willis Electric Co., Ltd. | Dual-voltage lighted artificial tree |
US9220361B1 (en) | 2013-12-03 | 2015-12-29 | Willis Electric Co., Ltd. | Dual-voltage lighted artificial tree |
US9883566B1 (en) | 2014-05-01 | 2018-01-30 | Willis Electric Co., Ltd. | Control of modular lighted artificial trees |
US10683974B1 (en) | 2017-12-11 | 2020-06-16 | Willis Electric Co., Ltd. | Decorative lighting control |
US10989374B1 (en) | 2017-12-11 | 2021-04-27 | Willis Electric Co., Ltd. | Decorative lighting control |
US11353176B1 (en) | 2017-12-11 | 2022-06-07 | Willis Electric Co., Ltd. | Decorative lighting control |
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