US3855521A - Transformer having switch means for causing series or parallel connection between plural primary or secondary winding - Google Patents
Transformer having switch means for causing series or parallel connection between plural primary or secondary winding Download PDFInfo
- Publication number
- US3855521A US3855521A US00362061A US36206173A US3855521A US 3855521 A US3855521 A US 3855521A US 00362061 A US00362061 A US 00362061A US 36206173 A US36206173 A US 36206173A US 3855521 A US3855521 A US 3855521A
- Authority
- US
- United States
- Prior art keywords
- rotary
- transformer
- voltage
- short
- taps
- 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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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F29/00—Variable transformers or inductances not covered by group H01F21/00
- H01F29/02—Variable transformers or inductances not covered by group H01F21/00 with tappings on coil or winding; with provision for rearrangement or interconnection of windings
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F29/00—Variable transformers or inductances not covered by group H01F21/00
- H01F29/02—Variable transformers or inductances not covered by group H01F21/00 with tappings on coil or winding; with provision for rearrangement or interconnection of windings
- H01F29/025—Constructional details of transformers or reactors with tapping on coil or windings
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/0005—Tap change devices
- H01H9/0011—Voltage selector switches
Definitions
- a voltage adapting apparatus which has a transformer with primary and secondary windings, one of which has a plurality of separate windings and taps which are independent from each other, and a rotary switch for interconnecting the taps to an external, commercial, A.C. source so that a constant voltage is obtained at the transformer secondary winding when any one of a plurality of AC. voltages is applied through the switch to the primary windings.
- the switch includes a terminal board with a central fixed terminal, a plurality of fixed terminals arranged in plural coaxial circles around the central terminal and a rotary insulating member which has a pair of spring mounted short circuit contacts arranged parallel to each other, the first short circuit contact connecting with the central terminal and with one of a plurality of solid terminals intersecting one of the plural coaxial circles and the second short circuit element being selectively connected to two or more of the fixed terminals on another of the coaxial circles.
- the present invention relates generally to voltage I adapting devices and more particularly to such adapting devices which have a transformer and a voltage selecting switch for producing a constant A.C. output voltage from a plurality of different commercial A.C.
- the A.C. voltages of different commercial systems vary greatly. For example in some parts of Europe the commercial electric power source is 220 volts while in other parts of Europe it is 240 volts. In the United States and some other western countries it is 1 volts. Furthermore the voltage may vary even in the same country. 1
- the appliance When a traveler goes from one country to another with an electric appliance such as a magnetic taperecorder, a radio or the like, the appliance must be adapted to'operate on the different commercial voltages because the actual operating voltage used byv the appliance is a set, predetermined voltage.
- the adapting circuit is built into the appliance itself while in other devices it is separate from it and includesa rectangular plug terminal board with a jack base plate attached to the housing of the apparatus and a transformer connected to the jack.
- ap-- paratus often include detachable parts which may become lost, rendering the apparatus useless.
- the changing of the voltage adapting apparatus from one country to the next is a relatively complicated operation.
- Still another disadvantage of some prior art voltage adapting devices is that if it is built in the electronic appliance it consumes excess space and requires excessive recesses in the housing of the appliance.
- a voltage adapting apparatus comprising a terminal board-having a plurality of conduc tive terminals arranged in co-axial circles, a transformer having a plurality of windings and taps on each winding to be connected to the plurality of conductive terminals in selected patterns and a rotary insulating member rotatably supported by the terminal board and having connectors for connecting the conductive terminals in pre-selected patterns so that the separate windings and taps of the transformer are connected variously in series or in parallel configurations to the external commercial A.C. source whereby a constant output voltage is obtained for any one of a plurality of A.C. input voltages.
- FIG. I is a schematic circuit diagram of one embodiment of the invention.
- FIGQ2 is a top plan view of the selecting switch of the embodiment of FIG. I;
- FIG. 3 is a side view of the selecting switch depicted in FIG. 2;
- FIG. 4 is a top plan view of a terminal board forming a part of the selecting switch of the embodiment of FIG. 1;
- FIG. 5 is a cross-sectional view taken generally along the line V ⁇ / in FIG. 4;
- FIG. 6 is a top plan view of a rotary element forming a part of a selecting switch depicted in FIG. 2;
- FIG. 7 is a cross-sectional view'taken generally along the line VII-VII in FIG.'6; 7
- FIGS. 8A, 8B and 8C are perspective views of the short circuiting elements and a ball and spring arrangement provided for use in the switch depicted in FIG. 2, respectively;
- FIGS. 9 to 12, inclusive are schematic circuit diagrams showing the effective connections of the transformer for various positions of the rotary selecting A former for a second embodiment of the invention.
- FIG. 14 is an enlarged, diametrical sectional view of the assembled selecting switch illustrated by FIGS. 2 to SC, inclusive.
- a transformer TR according to the present invention has a primary winding L, which is divided into afirst winding member L and a second winding member L
- the first winding member L has a reference terminal or tap r, at one end, a tap at its other end and a tap r, at an intermediate point between the taps t, and 1
- the voltages to be applied to the taps t I, and t; of the winding L would typically be 0, 20 and volts, respectively.
- a second winding L has a reference terminal or tap t, at one end, a tap 1 at its other end and an intermediate tap 1
- the alternating current voltages which typically would be applied to the taps t t and t are 0, I I0 and 130 volts, respectively.
- the taps on the windings I. and L are variously interconnected with each other by means of a switch SW to be in parallel or in series to provide a constant output voltage at the secondary winding L,
- the selecting switch SW includes a terminal board 1 having a plurality of solid, electrically conductive terminals and a rotary insulating button 2 which has affixed to it a plurality of short circuit elements S, and S for short circuiting selected ones of the solid conductive terminals.
- the terminal board 1 is formed from a substantially disc-shaped insulator and has a circular recess 1A (FIG. 5) in its center portion. At the bottom of the circular recess 1A there are provided a plurality of solid contacts T,, T T T and T plus a center contact T The contact T is spaced from the center terminal by a predetermined distance which forms the radius of a hypothetical circle C,.
- the terminal T is located approximately in the three o'clock position as viewed in FIG. 4.
- the other terminals are located at a slightly larger radius from the center terminal T along a hypothetical circle C If the position of the terminal T is taken as the positions of the terminals T T and T, are at approximately 45, 225 and 315, respectively.
- the terminal T is located so as to extend in such a manner that it intersects the circle C, at a rotary position of approximately 90 and intersects the circle C at a rotary position of approximately. 135.
- the portion of the terminal T, which intersects the circle C, is designated T, and the portion which intersects the circle C is designated T,,,.
- the terminals T,T,,, inclusive, are provided with outer leads T,T,,', respectively, which project beyond the rear surface 1B of the terminal board 1, as is more clearly shown in FIGS. 3 and 5. These leads T, T are connected to the terminals 1, I, of the coil L, of the transformer TR as follows:
- Terminals of Transformer TR Furthermore, the terminal lead T, and the terminal lead T are connected to the separate leads of the utility plug 3.
- the rotary button 2 of the selecting switch SW includes an insulating disc-like base portion 2A and a circular, post-like projection 28 as illustrated in FIGS. 6 and 7.
- the portions 2A and 2B are made integrally from an insulative material such as phenol resin.
- a low height, short-circuit element S (FIG. 8B) is inserted in a shallow recess 2a in the bottom portion of the button 2, as shown on FIG. 14, so that one end of the short-circuit element 8,, such as a contact 8,, will contact the central terminal T and the other end of the element 5,, such as a contact S will contact either the terminal T or the'end of the terminal T, when the button -2is rotated.
- a second or high-height, short-circuit element S is fitted in a recess 212 at the outer perimeter of the button 2, as shown on FIG.
- the short-circuit elements S, and S are formed of a conductive material such as phosphor bronze plate which is bent to have a substantially V-shape.
- the rotary button 2 has a bore 2c into which a spring Sp is fitted. A metal ball B0 is then placed on top of the spring to form a stop member for the rotary switch as will be explained in greater detail hereinafter.
- the portion 2B has'an elongated groove or slit 2:] in its upper surface which is designed to receive, for example, a coin to facilitate the rotation of the rotary button 2.
- the rotary button 2 is further marked with a recessed arrow 2e on the top surface of the member 28 for indicating the voltage (not shown) corresponding to the rotated position of the rotary button 2.
- the rotary button 2 is rotatably assembled to the terminal board 1 by means of a metal cover 3 which has an opening 3a in its center'to receive the projecting portion 28 of the button 2.
- the metal cover also has four slits 3d, 3e, 3f and 3g arranged at 90 angles about the opening 3a. The positions of the slits are designed to engage with the spring biased metal ball Bo and to stop the rotary button 2 at predetermined positions corresponding to the switch contacts.
- the cover 3 further has tangs 3h and bores 3b and 3c which correspond to bores la and lb in the terminal board 1. Referring in detail to FIG. 14, it will be seen that the assembly of the switch SW is as follows:
- the short-circuit elements S, and S are inserted in their respective recesses 2a and 2b in the rotary button 2.
- the button portion 2A is inserted into the recess 1A of the terminal board I and the spring Sp and the metal ball B0 areinserted into the hole 20 of the rotary button 2.
- the cover 3 is thereafter mounted on the terminal board 1 from above in such a manner that the opening 3a in the cover coincides with the projecting member 28 of the rotary button 2 to hold the rotary member in. rotatable engagement with the terminal board 1. Thereafter the tangs 311 of the cover 3 are bent downwardly to engage with engaging portions 1C and ID of the terminal board 1, respectively.
- the outer leads T, through T6, inclusive, of the terminal board I are thereafter interconnected with the terminals r, 1,, of the transformer TR and the leads of the power plug 3 in the manner described above.
- the selecting switch SW has therefore been assembled with no screws or the like and is thereafter attached to the electronic appliance by means of screws through the bores 3b and 3c in the cover 3 and the bores la and lb of the terminal board I.
- the transformer taps t and 1 are connected to each other as are also the taps I and Accordingly, the connections among the terminals of the transformer TR and the electric power source plug 3 become as shown in FIG. 9. With these connections the portion of the first winding L,, between the taps t and 1,, and the portion of the second winding L, between the taps t and 1,, are connected in parallel with each other with respect to the power source plug 3. Thus when a voltage of volts of alternating current is supplied to the power source plug 3, a predetermined output voltage is produced across the secondary winding L of the transformer TR.
- the rotary button 2 may be rotated relative to the terminal board 1 to a plurality of positions in correspondence with input voltages of I10, 220, 240 and 130 volts A.C. to obtain the same predetermined output voltage across the secondary winding L of the transformer TR.
- the primary winding of the transformer may be composed of three or more windings.
- the switch SW may be interconnected with a secondary winding L, which is composed of two separate windings L and L having a plurality of taps. With such a transforrner'TR' there is only a single primary winding L, which is connected to the power source terminal 3.
- the terminals of the switch SW are interconnected in a manner similar to that in the embodiment described above so that the same output voltage is derived from the switch SW for a plurality of input A.C. voltages to the primary winding L,.
- the solid terminals of the terminal board 1 may be disposed in three or more coaxial circles. In these embodiments the number of short circuit elements is increased.
- a voltage selecting apparatus comprising:
- a transformer having a primary winding and a secondary winding, one of which includes a plurality of separate windings, each of said separate windings having a plurality of taps;
- housing means having a plurality of fixed terminals predetermined ones of said fixed terminals being disposed about the periphery of at least two individual coaxial circles and one of said fixed terminals being disposed at the center of said coaxial-circles;
- rotary button means mounted for rotation with respect to said housing and having at least two short circuit members supported in said rotary button means and rotatable therewith, a first of said shortcircuit members defining a chord of one of said coaxial circles to thereby selectively short-circuit a pair of said fixed contacts disposed about the periphery of said one coaxial circle in accordance with the rotary position of said button means, and a second of said short-circuit members being in contact with said one fixed terminal disposed at said center of said coaxial circles and being substantially pivotable thereabout to thereby selectively short-circuit said one fixed terminal and a selected fixed terminal disposed about the periphery of another of said coaxial circles in accordance with said rotary position of said button means, such that preselected ones of said taps are electrically interconnected in predetermined circuit configurations whereby a single predetermined output voltage is derived from said transformer when said button means is rotated into corresponding rotary positions associated with different AC voltage magnitudes supplied to said transformer.
- a voltage selecting apparatus wherein the housing means has a circular recessin which the fixed terminals are disposed and the rotary button means is rotatably retained in the recess.
- a voltage selecting apparatus wherein the rotary button means is provided with a plurality of recesses in which the short-circuit members are disposed.
- a voltage selecting apparatus according to claim 5, wherein the rotary button-means has formed on its upper surface an elongated groove to facilitate the manual rotation of the rotary button means.
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Details Of Connecting Devices For Male And Female Coupling (AREA)
- Rotary Switch, Piano Key Switch, And Lever Switch (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1972060771U JPS5636103Y2 (fr) | 1972-05-24 | 1972-05-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3855521A true US3855521A (en) | 1974-12-17 |
Family
ID=13151866
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00362061A Expired - Lifetime US3855521A (en) | 1972-05-24 | 1973-05-21 | Transformer having switch means for causing series or parallel connection between plural primary or secondary winding |
Country Status (7)
Country | Link |
---|---|
US (1) | US3855521A (fr) |
JP (1) | JPS5636103Y2 (fr) |
BR (1) | BR7303848D0 (fr) |
CA (1) | CA1000791A (fr) |
FR (1) | FR2185845B1 (fr) |
GB (1) | GB1416918A (fr) |
NL (1) | NL7307288A (fr) |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4109132A (en) * | 1977-02-22 | 1978-08-22 | Aristotel Butoi | Automatic welding mask shutter lens system |
US4222099A (en) * | 1978-10-12 | 1980-09-09 | Medi-Technical Corporation | Power supply |
US4415964A (en) * | 1981-12-28 | 1983-11-15 | Scharfe Jr James A | Power supply |
US4441149A (en) * | 1982-02-10 | 1984-04-03 | Hase A M | Multi-voltage transformer input circuits with primary reactor voltage control |
US4519826A (en) * | 1983-04-14 | 1985-05-28 | The United States Of America As Represented By The Secretary Of The Navy | Optical fibers having a fluoride glass cladding and method of making |
US4621298A (en) * | 1985-05-31 | 1986-11-04 | General Electric Company | Dual voltage distribution transformer with internal varistor surge protection |
US4772806A (en) * | 1987-05-01 | 1988-09-20 | Shay Lean | Switching device for a series loop circuit |
US4775766A (en) * | 1987-04-15 | 1988-10-04 | Electro-Voice, Incorporated | Tapped transformer/switch assembly |
US4862307A (en) * | 1988-07-06 | 1989-08-29 | General Electric Company | Dual voltage distribution transformer with internal varistor surge protection |
US5929402A (en) * | 1996-11-29 | 1999-07-27 | Charles Industries, Ltd. | Switchable load coil case including multiple circuit rotary switch assembly |
US6281454B1 (en) | 1996-11-29 | 2001-08-28 | Charles Industries, Ltd. | Switchable load coil case |
US20050016823A1 (en) * | 2003-07-24 | 2005-01-27 | Ali Mohammed Ershad | High speed channel selector switch |
US20050243859A1 (en) * | 2004-04-30 | 2005-11-03 | Ali Mohammed E | Method and apparatus for high-speed multiple channel and line selector switch |
US20060017537A1 (en) * | 2004-07-22 | 2006-01-26 | Alberto Prieto Colmenero | Multi-voltage power transformer for the high-voltage electricity transmission network |
CN101488412B (zh) * | 2008-01-18 | 2011-05-04 | 松下电器产业株式会社 | 旋转操作型编码器及其制造方法 |
CN103280303A (zh) * | 2013-05-29 | 2013-09-04 | 卧龙电气集团股份有限公司 | 油浸式变压器的双重串并联转换接线装置 |
EP2782107A1 (fr) * | 2013-03-19 | 2014-09-24 | LG Electronics, Inc. | Transformateur haute tension |
CN116313451A (zh) * | 2023-05-11 | 2023-06-23 | 三尔梯(泉州)电气制造有限公司 | 单相双极电抗器、稳压装置、三相双极电抗器及其应用 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3201684A (en) * | 1961-09-29 | 1965-08-17 | Westinghouse Electric Corp | Dual voltage transformer winding connection |
US3711747A (en) * | 1970-08-13 | 1973-01-16 | Sony Corp | Power transformer primary winding fuse arrangement |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1094770A (fr) * | 1955-05-24 | |||
JPS4312336Y1 (fr) * | 1966-10-25 | 1968-05-28 |
-
1972
- 1972-05-24 JP JP1972060771U patent/JPS5636103Y2/ja not_active Expired
-
1973
- 1973-05-18 GB GB2385573A patent/GB1416918A/en not_active Expired
- 1973-05-21 US US00362061A patent/US3855521A/en not_active Expired - Lifetime
- 1973-05-23 CA CA172,004A patent/CA1000791A/en not_active Expired
- 1973-05-24 FR FR7318961A patent/FR2185845B1/fr not_active Expired
- 1973-05-24 NL NL7307288A patent/NL7307288A/xx not_active Application Discontinuation
- 1973-05-24 BR BR003848/73A patent/BR7303848D0/pt unknown
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3201684A (en) * | 1961-09-29 | 1965-08-17 | Westinghouse Electric Corp | Dual voltage transformer winding connection |
US3711747A (en) * | 1970-08-13 | 1973-01-16 | Sony Corp | Power transformer primary winding fuse arrangement |
Cited By (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4109132A (en) * | 1977-02-22 | 1978-08-22 | Aristotel Butoi | Automatic welding mask shutter lens system |
US4222099A (en) * | 1978-10-12 | 1980-09-09 | Medi-Technical Corporation | Power supply |
US4415964A (en) * | 1981-12-28 | 1983-11-15 | Scharfe Jr James A | Power supply |
US4441149A (en) * | 1982-02-10 | 1984-04-03 | Hase A M | Multi-voltage transformer input circuits with primary reactor voltage control |
US4519826A (en) * | 1983-04-14 | 1985-05-28 | The United States Of America As Represented By The Secretary Of The Navy | Optical fibers having a fluoride glass cladding and method of making |
US4621298A (en) * | 1985-05-31 | 1986-11-04 | General Electric Company | Dual voltage distribution transformer with internal varistor surge protection |
US4775766A (en) * | 1987-04-15 | 1988-10-04 | Electro-Voice, Incorporated | Tapped transformer/switch assembly |
US4772806A (en) * | 1987-05-01 | 1988-09-20 | Shay Lean | Switching device for a series loop circuit |
US4862307A (en) * | 1988-07-06 | 1989-08-29 | General Electric Company | Dual voltage distribution transformer with internal varistor surge protection |
US5929402A (en) * | 1996-11-29 | 1999-07-27 | Charles Industries, Ltd. | Switchable load coil case including multiple circuit rotary switch assembly |
US6281454B1 (en) | 1996-11-29 | 2001-08-28 | Charles Industries, Ltd. | Switchable load coil case |
US6933628B2 (en) * | 2003-07-24 | 2005-08-23 | Agilent Technologies, Inc. | High speed channel selector switch |
US20050016823A1 (en) * | 2003-07-24 | 2005-01-27 | Ali Mohammed Ershad | High speed channel selector switch |
US7508823B2 (en) * | 2004-04-30 | 2009-03-24 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Method and apparatus for high-speed multiple channel and line selector switch |
US20050243859A1 (en) * | 2004-04-30 | 2005-11-03 | Ali Mohammed E | Method and apparatus for high-speed multiple channel and line selector switch |
US7692523B2 (en) | 2004-07-22 | 2010-04-06 | Asea Brown Boveri, S.A. | Multi-voltage power transformer for the high-voltage electricity transmission network |
ES2257161A1 (es) * | 2004-07-22 | 2006-07-16 | Abb Power Technology, S.A. | Transformador de potencia multi-tension para red de transmision de energia electrica de alta tension (politrafo). |
WO2006021597A1 (fr) * | 2004-07-22 | 2006-03-02 | Asea Brown Boveri, S.A. | Transformateur de puissance multitension pour reseau de transmission d'energie electrique haute tension (politrafo) |
US20060017537A1 (en) * | 2004-07-22 | 2006-01-26 | Alberto Prieto Colmenero | Multi-voltage power transformer for the high-voltage electricity transmission network |
CN101488412B (zh) * | 2008-01-18 | 2011-05-04 | 松下电器产业株式会社 | 旋转操作型编码器及其制造方法 |
EP2782107A1 (fr) * | 2013-03-19 | 2014-09-24 | LG Electronics, Inc. | Transformateur haute tension |
CN103280303A (zh) * | 2013-05-29 | 2013-09-04 | 卧龙电气集团股份有限公司 | 油浸式变压器的双重串并联转换接线装置 |
CN103280303B (zh) * | 2013-05-29 | 2016-01-27 | 卧龙电气集团股份有限公司 | 油浸式变压器的双重串并联转换接线装置 |
CN116313451A (zh) * | 2023-05-11 | 2023-06-23 | 三尔梯(泉州)电气制造有限公司 | 单相双极电抗器、稳压装置、三相双极电抗器及其应用 |
CN116313451B (zh) * | 2023-05-11 | 2023-08-29 | 三尔梯(泉州)电气制造有限公司 | 单相双极电抗器、稳压装置、三相双极电抗器及其应用 |
Also Published As
Publication number | Publication date |
---|---|
FR2185845A1 (fr) | 1974-01-04 |
JPS4920030U (fr) | 1974-02-20 |
GB1416918A (en) | 1975-12-10 |
FR2185845B1 (fr) | 1978-02-17 |
BR7303848D0 (pt) | 1973-12-20 |
NL7307288A (fr) | 1973-11-27 |
JPS5636103Y2 (fr) | 1981-08-25 |
CA1000791A (en) | 1976-11-30 |
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