US3728656A

US3728656A - Transormer and terminal assembly

Info

Publication number: US3728656A
Application number: US00266438A
Authority: US
Inventors: R Neuber
Original assignee: GTE Sylvania Inc
Current assignee: GTE Sylvania Inc
Priority date: 1972-06-26
Filing date: 1972-06-26
Publication date: 1973-04-17
Anticipated expiration: 1990-04-17

Abstract

A terminal assembly is shown wherein connections between selected terminals of a terminal block are made by a jumper strip. The terminal assembly is utilized to change the winding arrangement of a power transformer.

Description

0 United States Patent 1191 1111 3,728,656 Neuber 1 Apr. 17, 1973 TRANSORMER AND TERMINAL [56] References Cited ASSEMBLY UNITED STATES PATENTS [75] Inventor: Ralph E. Neuber, Seneca Falls,

2,464,061 3 1949 Soley, Jr ..323 49 x 531,432 l2/l894 Beu ..323/49 [73] Assignee: GTE Sylvania Incorporated, Seneca 2,786,162 3/1957 Ballou ..3l7/119 Falls,N.Y. 2,552,028 5/1951 Blair ..310/71 Fiidl J 1972 Primary Examiner-Thomas .l. Kozma 1 pp No: Attorney-Norman J. OMalley 6t al.

Related US. Application Data [57] ABSTRACT Division Of 1971, abfln- A terminal assembly is shown wherein connections donedbetween selected terminals of a terminal block are made by a jumper strip. The terminal assembly is util- [52] US. Cl. ..336/l47, 323/49, 336/192, ized to change the winding arrangement of a power 339/19, 339/222 transforms, [51] Int. Cl ..H01f 21/12 [58] Field of Search ..336/l45, 146, 147,

336/192; 323/48, 49; 339/198 R, 19, 22 B, 263, 242, 210 R; 317/119; 310/71 10 Claims, 3 Drawing Figures PATENTED A R 1 1 ms Y sum 1 BF 2 Pmmawm 11m 3,728,656

SHEET 2 [IF 2 96 RECTIFIER O l6 I5 95 23 22 v 2 20 82 al so 77 POWER SOURCE I82 srI I TRANSORMER AND TERMINAL ASSEMBLY CROSS-REFERENCE TO RELATED APPLICATION This application is a division of application Ser. No. 112,863, filed Feb. 5, 1971, now abandoned, and assigned to the same assignee as the present invention.

BACKGROUND OF THE INVENTION This invention relates to terminal assemblies and more particularly to terminal assemblies wherein terminal connections can be changed rapidly and easily' with decreased danger of injury to equipment and personnel. In the prior art numerous methods of changing terminal connections have been utilized. These methods include various types of jumper leads with various types of clips, clamps, and plugs.

An example of one setting where the prior art does not provide a satisfactory method of changing terminal connections is in Community Antenna Television (CATV) systems. CATV systems include a transmission cable with amplifier stations dispersed therealong for maintaining proper RF signal levels. Each amplifier station must be powered. Ordinarily, a 60 Hz ac power signal is multiplexed onto the cable and at each amplifier station the 60 Hz ac power signal is separated from the RF signals. The power signal is coupled to a transformer and from there to a rectifier. In the past, most CATV systems used 30 volt power, but it is common to find 60 volt power being used and in some systems both 60 and 30 volt power may be used. To accommodate both 30 and 60 volt power, the transformer is designed with either two primary windings or two secondary windings which are placed in series or parallel depend in g upon the voltage of the power signal.

The ordinary practice is to solder the winding leads to terminals so that changing a transformer from 30 to 60 volt operation or 'vice versa requires unsoldering and resoldering a number of connections. In other cases, a terminal board is used with jumpers used to change the connections. In either case there is the danger of incorrect connections which may cause damage to equipment and/or personal injury.

OBJECTS AND SUMMARY OF THE INVENTION It is the primary object of this invention to obviate the above-noted disadvantages of the prior art.

It is another object of this invention to provide a novel means for changing the jumper arrangement for a terminal assembly.

It is a further object of this invention to provide a novel means for rapidly and safely changing the winding arrangement of a transformer.

In one aspect of this invention, the above objects and advantages are achieved in a transformer and terminal assembly comprised of a transformer, a terminal block, and a terminal jumper wherein the transformer has first and second windings and the terminal block has a plurality of aligned terminals. The windings of the transformer are selectively connected to the terminals. The terminal jumper has a flat conductive strip encapsulated in an insulative handle. The flat conductive strip has a first portion for contacting one of the terminals and a second portion for contacting another of the terminals whereby the contacted terminals are electrically connected together. The terminal jumper is connectable in at least two positions on the terminal block for connecting one pair of terminals together or for connecting another pair of terminals together whereby the transformer windings are connected in series or other than in series.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded isometric view of a structure embodying the invention; and

FIGS. 2 and 3 are schematic and block diagrams illustrating an application of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the above drawings.

In FIG. 1 there is shown a transformer 10 having a plurality of leads 11-16. Leads 11-14 are connected to terminals 20-23, respectively, of a terminal block 17.

Leads

15 and 16 are connected to

terminals

27 and 30, respectively, of a terminal block 26 which also has

terminals

24 and 25 thereon.

Terminal blocks

17 and 26 are preferably identical so that one design can be used interchangeably. Terminal blocks 17 and '26 are constructed 0f insulative material such as plastic, and the terminals preferably each include a conductor protruding through the block with a depending stud on the underside of the terminal blocks to which leads 11-16 are soldered. Each of the terminals has a threaded screw-' type insert.

Preferably

terminal blocks

17 and 26 are mounted on transformer 10 by a pair of

brackets

31 and 32. Bracket 31 is attached to transformer 10 by

screws

33 and 34 which extend through holes 35 and 36 in tabs 37 and 40, respectively, of a lower flange 41 of bracket 31 and into

holes

42 and 43, respectively, in the casing of transformer 10. Bracket 32 is attached to transformer 10 by

screws

44 and 45 which extend through holes 46 and 47 in

tabs

50 and 51, respectively, of a lower flange 52 of bracket 32 and into

holes

53 and 54, respectively, in the casing of transformer 10. Terminal block 17 is mounted on

brackets

31 and 32 by bolts or

screws

55 and 56 which extend through holes 57 and, respectively, near the ends of terminal block 17 and through

holes

61 and 62, respectively, in

upper flanges

63 and 64 of

brackets

31 and 32, respectively. Similarly, terminal block 26 is mounted on

brackets

31 and 32 by bolts or

screws

65 and 66 which extend through holes 67 and 70, respectively, near the ends of terminal block 26 and through holes 71 and 72, respectively, in

upper flanges

63 and 64 of

brackets

31 and 32. Although

terminal blocks

17 and 26 are shown mounted on transfonner 10, they can also be mounted in other ways.

A terminal jumper 73 is shown with a flat insulative handle 74 and two flat

conductive strips

75 and 76.

Conductive strips

75 and 76 are fixedly attached to and extend from one edge of handle 74. Preferably strips 7.5 and 76 are encapsulated or encased in handle 74, for example, by laminating or gluing two flat pieces of insulative material such as plastic together on opposite sides of

strips

75 and 76.

Conductive strip 75 has first and second grooved or forked

portions

77 and 80. Conductive strip 76 has first and second grooved or forked

portions

81 and 82. The forked

portions

77, 80, 81, and-82 are designed for cooperative engagement with the threaded inserts of terminals 20-23 of terminal block 17, for example, by loosening the screws in the threaded inserts, inserting the forked portions beneath the screw heads, and tightening the screws into the inserts.

A protective cover 83 of insulative material is also provided as a safety feature. Cover 83 is attached to

brackets

31 and 32 by

screws

84 and 85 which extend through

holes

86 and 87, respectively, in cover 83 into bosses 90 and 91 mounted respectively on the

upper flanges

63 and 64 of

brackets

31 and 32. Cover 83 has a plurality of holes therein to permit access to the terminal inserts so that changes in the terminal connections can be made without removing cover 83. Cover 83 tends to prevent inadvertent contact with the terminals.

FIGS. 2 and 3 illustrate the electrical configuration of transformer 10 and the terminal connections. A power source 92, which can be the means for providing the ac power signal in a'CATV system, has first and second outputs connected to

terminals

20 and 23, respectively. One of

terminals

20 and 23, for example, terminal 20 can be connected to ground. Transformer 10 has two

primary windings

93 and 94 and a secondary winding 95. One end of winding 93 is connected by conductor 11 to terminal 20 while the other end is connected by conductor 13 to terminal 22. One end of winding 94 is connected by conductor 12 to terminal 21 while the other end is connected by conductor 14 to terminal 23. One end of winding 95 is connected by conductor 15 to terminal 27 while the other end is connected by conductor 16 to terminal 30.

Terminals

27 and 30 are connected to a rectifier 96 which has a positive dc output connected to terminal 25 and a negative dc output connected to terminal 24.

To understand the operation of the invention, assume that source 92 provides either 30 or 60 volt ac power. If 30 volt ac poweris being provided, terminal jumper 73 is connected to terminals 20-23 such that

portions

77,80, 81 and 82 of

conductive strips

75 and 76 contact terminals 20-23, respectively, as is shown in FIG. 2.

Terminals

20 and 21 are connected together by conductive strip 75 while

terminals

22 and 23 are connected togetherby conductive strip 76 thereby connecting

windings

93 and 94 in parallel between

terminals

20 and 23.

If 60 volt ac power is being provided, terminal I jumper 73 is moved one position left or right. Assume that it is moved to the position illustrated in FIG. 3 such that

portions

81 and 82 of conductive strip 76

contact terminals

21 and 22, respectively. Portion 80 of conductive strip 75 contacts terminal 20 while portion 77 contacts a dummy terminal 97 which may be screw 55 of FIG. 1. Accordingly, screw 55 is preferably insulating (e.g., plastic) as a safety feature. Thus,

terminals

21 and 22 are connected together by conductive strip 76 and

windings

93 and 94 are connected in series between

terminals

20 and 23.

In general, the voltage across the secondary winding 6 of a transformer v, is related to the primary winding voltage v,, by the equation v. (NJN,)v, where NJN,

is the turns ratio of the secondary and primary windings. If

windings

93 and 94 have the same number I when

windings

93 and 94 are connected in series for 60.

volt operation as is illustrated in FIG. 3. Connecting

windings

93 and 94 in parallel as is illustrated in FIG. 2 decreases the current in the primary winding by half. Note, however, that if only one winding is used in the illustration of FIG. 2, only one of conductive strips and 76 is necessary.

Another feature of this invention is the cooperative indicia provided for indicating the proper position of terminal jumper 73 with respect to terminal block 17. The numbers 30 and 60 are provided on cover 83 and a cooperating arrow is provided on handle 74 in such positions that the arrow points to the proper one of the numbers on cover 83 when terminal jumper 73 is properly positioned.

It should be noted that terminal block 17 could be provided with 6 terminals with two others being used for the secondary winding while the outputs from rectifier 96 are otherwise accommodated, or alternatively, the secondary winding terminals could also be otherwise accommodated. It should also be noted that trans} former 10 can have one primary winding and two secondary windings which are discretionarily connected in accordance with the invention to achieve the same result.

While there has been shown and described what is at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.

What is claimed is:

1. A transformer and terminal assembly comprising:

a transformer having first and second windings;

a terminal block havinga plurality of aligned terminals insulated from each other; means connecting said windings to said terminals and a terminal jumper having a flat conductive strip en capsulated in an insulative handle, said flat conductive strip having a first portion for contacting one of said terminals and a second portion for contacting another of said terminals whereby said flat conductive strip electrically connects the contacted terminals together, said terminal jumper selected ones of being connectable in at least two positions on'said said plurality of terminals, a first end of said second winding to a second terminal of said plurality of terminals, and a second end of said first winding to a third terminal of said plurality of terminals; and wherein said first portion of said flat conductive strip electrically contacts said first terminal or said second terminal and said second portion electrically contacts said second terminal or said third terminal for alternatively connecting said first ends of said second windings together or connecting said first end of said second winding to said third terminal.

3. A transformer and terminal assembly as defined in claim 1 wherein said insulative handle includes first and second flat strips of insulative material fixedly attached to each other on opposite sides of said flat conductive strip.

4. A transformer and terminal assembly as defined in claim 2 wherein a second end of said second winding is connected to a fourth terminal of said plurality of terminals and said terminals jumper includes a second flat conductive strip encapsulated in said insulative handle and insulated from said first-named flat conductive strip, said second conductive strip having a first portion and a second portion for electrically contacting said first terminal and said fourth terminal, respectively, when said first portion and second portion of said firstnamed flat conductive contact said second terminal and third terminal, respectively, for connecting said first and second windings in parallel between said third and fourth terminals.

5. A transformer and terminal assembly as defined in claim 4 wherein said insulativejhandle includes first and second flat strips of insulative material fixedly attached to each other on opposite side of said first-named and said second conductive strips.

6. A transformer and terminal assembly as defined in claim 1 wherein said terminal block is constructed of an insulative material, said terminals each include a conductor protruding through said terminal block with a threaded insert for clamping one of said first or second portions of said flat conductive strip, and each of said first and second portions of said flat conductive strip include a forked portion for cooperative engagement with said threaded inserts.

7. A transformer and terminal assembly as defined in claim 4 wherein said insulative handle and the terminal assembly include cooperative indicia for indicating the proper position of said terminal jumper with respect to said terminal block.

8. A transformer and terminal assembly comprising:

a transformer having first and second windings;

a terminal block having a plurality of aligned terminals insulated from each other;

means connecting first and second ends of said first winding to first and second ones of said terminals, respectively, and first and second ends of said second winding to third and fourth ones of said terminals, respectively; and

a terminal jumper having at least first and second flat conductive strips encapsulated in an insulative handle, said flat conductive strips each having a first portion for contacting one of said terminals and a second portion for contacting another of said terminals whereby each of said flat conductive strips electrically connects the contacted terminals together, said umper strip being connectable m at least two positions on said terminal block for connecting said second and third terminals together for connecting said first and second windings in series or for connecting said first terminal to said third terminal and said second terminal to said fourth terminal for connecting said first and second windings in series.

9. A transformer and terminal assembly as defined in claim 8 wherein said insulative handle includes first and second flat strips of insulative material fixedly attached to each other on opposite sides of said flat conductive strips.

10. A transformer and terminal assembly as defined in claim 9 wherein said terminal block is constructed of an insulative material and said terminals each include a conductor protruding through said terminal block with a threaded insert for clamping one of said first and second portions of said first and second flat connective strips.

Claims

1. A transformer and terminal assembly comprising: a transformer having first and second windings; a terminal block having a plurality of aligned terminals insulated from each other; means connecting said windings to selected ones of said terminals; and a terminal jumper having a flat conductive strip encapsulated in an insulative handle, said flat conductive strip having a first portion for contacting one of said terminals and a second portion for contacting another of said terminals whereby said flat conductive strip electrically connects the contacted terminals together, said terminal jumper being connectable in at least two positions on said terminal block for connecting one pair of terminals together whereby said first and second windings are connected in series or for connecting another pair of terminals together whereby said first and second windings are connected other than in series.

2. A transformer and terminal assembly as defined in claim 1 wherein said means connecting said windings to selected ones of said terminals includes means connecting a first end of said first winding to a first terminal of said plurality of terminals, a first end of said second winding to a second terminal of said plurality of terminals, and a second end of said first winding to a third terminal of said plurality of terminals; and wherein said first portion of said flat conductive strip electrically contacts said first terminal or said second terminal and said second portion electrically contacts said second terminal or said third terminal for alternatively connecting said first ends of said second windings together or connecting said first end of said second winding to said third terminal.

4. A transformer and terminal assembly as defined in claim 2 wherein a second end of said second winding is connected to a fourth terminal of said plurality of terminals and said terminals jumper includes a second flat conductive strip encapsulated in said insulative handle and insulated from said first-named flat conductive strip, said second conductive strip having a first portion and a second portion for electrically contacting said first terminal and said fourth terminal, respectively, when said first portion and second portion of said first-named flat conductive contact said second terminal and third terminal, respectively, for connecting said first and second windings in parallel between said third and fourth terminals.

5. A transformer and terminal assembly as defined in claim 4 wherein said insulative handle includes first and second flat strips of insulative material fixedly attached to each other on opposite side of said first-named and said second conductive strips.

8. A transformer and terminal assembly comprising: a transformer having first and second windings; a terminal block having a plurality of aligned terminals insulated from each other; means connecting first and second ends of said first winding to first and second ones of said terminals, respectively, and first and second ends of said second winding to third and fourth ones of said terminals, respectively; and a terminal jumper having at least first and second flat conductive strips encapsulated in an insulative handle, said flat conductive strips each having a first portion for contacting one of said terminals and a second portion for contacting another of said terminals whereby each of said flat conductive strips electrically connects the contacted terminals together, said jumper strip being connectable in at least two positions on said terminal block for connecting said second and third terminals together for connecting said first and second windings in series or for connecting said first terminal to said third terminal and said second terminal to said fourth terminal for connecting said first and second windings in series.