US3673360A

US3673360A - Booster transformer switch

Info

Publication number: US3673360A
Application number: US127667A
Authority: US
Inventors: John G Pahl
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-03-24
Filing date: 1971-03-24
Publication date: 1972-06-27
Anticipated expiration: 1989-06-27
Also published as: CA929996A

Abstract

A switch, of pole-mounted type, adapted for connection, in an electrical power supply system, between a feed cable and a load cable; the switch, in one position, normally providing direct connection between the feed cable and the load cable, and, in another position, breaking such direct connection and establishing a by-pass connection -including a booster transformer-between the feed cable and load cable whereby to ''''boost'''' the current value in said load cable under a condition of undue voltage drop therein. The switch also provides a shunt operative to prevent the load cable from being taken completely out-of-circuit as the switch is actuated from said one position to such other position; said shunt-which includes a resistor-also serving to preload the booster transformer, with less than the full feed voltage, before the switch closes in such other position.

Description

ited States Patent Pahl 1 June 27, 1972 [54] BOOSTER TRANSFORMER SWITCH Primary Examiner-Hennan .l. Hohauser Attorney-Webster & Webster [72) Inventor: John G. Plhl, 1624 E. Al ine Ave.,

Stockton. Calif. 95205 p [571 ABSTRACT [22] Filed: March 2. A switch, of pole-mounted type. adapted for connection, in an electrical power supply system, between a feed cable and a PP 127,567 load cable; the switch, in one position. normally providing direct connection between the feed cable and the load cable. and. in another position, breaking such direct connection and [52] [1.8. CI. JOB/48 R establishing a by-pass connection -including a booster trans- [Sl] Int. Cl. ..H0lh 31/00 former-between the feed cable and load cable whereby to [58] Field of Search ....200/48 R, 48 RP. 49, 50; boost" the current value in said load cable under a condition 307/112. I7, 85. 86, 87, 149 of undue voltage drop therein. The switch also provides a shunt operative to prevent the load cable from being taken Relerences Cited completely out-of-circuit as the switch is actuated from said one position to such other position; said shunt-which in- UNITED STATES PATENTS cludes a resistor-also serving to preload the booster trans- 3,274,364 9/1966 Sullivan et al ..200/4a ux former. with less than the full feed voltagebefore the switch 3,553,412 1/1971 Kerr ....2oo/4s R closes"! such othflpositioh 7 Claims, 6 Drawing Figures PATENTEflJum r912 SHEET 10F 2 Q3 IF INVENTOR.

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soos'rsa ramsroamsa swrrcl-r BACKGROUND OF THE INVENTION When the current value in a load cable, of an electrical power supply system, substantially reduces as a result of the demand thereon, the voltage drop is compensated for by means of a booster transformer then interposed between the feed cable and such load cable. This must be accomplished by a switch adapted for the purpose, and the present invention was conceived in the course of efforts to produce such a switch of pole-mounted type and one having commercial advantage both from the standpoint of ready manufacture and effective operation.

SUMMARY OF THE INVENTION The present invention provides, as a major object, a polemounted dual-position switch adapted for manual actuation between one position in which the switch provides a direct connection between a feed cable and a load cable, and another position in which said direct connection is broken and s by-pass connection-including a booster transformer-is established between the feed cable and load cable for the purpose of boosting the voltage in said load cable when an undue voltage drop occurs in the latter.

The present invention provides, as another object, a switch, as above, which includes a shunt automatically brought into play when the switch is actuated from said one position to such other position; the function of the shunt, which includes a resistor, being to prevent the load cable from being taken completely out-of-circuit as the switch is so actuated, and to pre-load the booster transformer, with less than full feed voltage, before the switch closes in such other position.

The present invention provides, as a further object, a booster transformer switch which is designed for ease and economy of manufacture.

The present invention provides, as a still further object, a practical, reliable, and durable booster transformer switch, and one which is exceedingly effective for the purpose for which it is designed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side elevation of the switch in its position providing direct connection between the feed cable and load cable.

FIG. 2 is a top plan of the switch as in FIG. I.

FIG. 3 is an end elevation of the same.

FIGS. 4, 5, and 6 are diagrammatic illustrations of certain positions of the switch.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now more particularly to the drawings and to the characters of reference marked thereon, the switch comprises, on a suitable mount l on a cross arm 2 of the pole P, a pair of spaced end-to-end insulators 3 and 4 disposed substantially horizontally; the insulator 3 being rotatably secured at its inner end to the mount I in a known manner, and rotation of such insulator being accomplished by the usual lever 5 adapted to connect to a push-pull rod R. At its outer end, the insulator 3 is connected to the feed cable 6 of the circuit phase to which the switch is related. The insulator 4, which is nonrotatably secured to the mount 1, is connected at the outer end to the load cable 7.

The rotatable insulator 3 carries a generally L-shaped arm 8 having a blade 9 at its outer end; such blade normally engaging in a clip 10 on the outer end of a generally L-shaped arm II carried by the non-rotatable insulator 4. As shown, the feed cable 6 and load cable 7 are electrically connected to the blade 9 and clip M, respectively.

The arms 8 and II, which are opposed, are shaped so thatupon part-circle rotation of insulator 3 and arm 8 by lever 5 and in a given direction-blade 9 escapes clip I0 and swings upwardly and inwardly through an arc in the vertical longitudinal plane of the cross arm 2.

A third insulator 12 is secured to the mount 1 and projects upwardly adjacent the insulators 3 and 4 and at a right angle to the axis thereof; the insulator 12 being fitted at its outer end with a short, rigid arm I3 which carries a clip 14 at its outer end. The clip 14 is disposed in the same transverse vertical plane as the clip I0 and faces the latter in spaced relation. The arrangement is such that-upon rotation of insulator 3 in the proper direction and resultant swinging of the arm 8-blade 9 escapes from clip 10 and engages in clip I4.

When the blade 9 is fully engaged in clip 10, the switchwhich is then in its normal position-provides a direct connection between the feed cable 6 and the load cable 7. See, for example, FIGS. 2 and 4. However, upon the occurrence of a load condition which causes an undue voltage drop in the load cable 7, the switch is actuated to cause blade 9 to escape clip 10 and fully engage in clip 14 as previously described. See FIG. 6. When blade 9 isso engaged in clip 14, a by-pass circuit or connection-including a pole-mounted booster transformer 15 shown diagrammatically in FIGS. 2, 4, 5, and 6-is established between the feed cable 6 and load cable 7.

More particularly, such by-pass connection includes, together with blade 9 and clip I4, leads I6 which couple the clip l4 to one side of the transformer, and a lead 17 which extends from the other side of the transformer to the load cable 7.

Thus, when the described by-pass circuit or connection is closed and operative, the booster transformer l5 functions to return the voltage in load cable 7 to the requisite value. Thereafter, when the load condition which caused the undue voltage drop is relieved, the switch is returned to its normal position with blade 9 free of clip l4 and engaged in clip 10.

In order to preclude the load cable from being taken wholly out-of-circuit when the switch is actuated from its direct-connection position (blade 9 engaged in clip ill), to its by-pass or "booster" position (blade 9 engaged in clip 14), and further to pre-load the transformer IS with less than full feed voltage before the switch closes in said by-pass position, a shunt is provided as follows:

An oval-shaped, spring blade wiper I8 is disposed adjacent and parallel to the transverse vertical plane occupied by the clips 10 and I4; such wiper l8 being positioned for electricalcontact engagement by the blade 9 as the latter swings in an are between said clips. The configuration, size, and position of the wiper 18 is such that the blade 9, as it is so swung, engages with such wiper l8 before total disengagement from clip 10 as shown in broken lines in FIG. 5, and initially engages with the clip I before total disengagement from said wiper as shown in broken lines in FIG. 6.

The wiper I8 is suspended in position by a bracket I9 on the adjacent end of a dielectric rod 20 which, in turn, is held in a fixed position by a bracket 21 secured on an arm 22 radiating from the outer end of insulator I2; the arm 22 being in electrical connection with the lead 16 running to transformer IS.

A resistor 23 of predetermined capacity is attached to, and spans between, the brackets I9 and 21 whereby to establish a resistor circuit between the wiper I8 and the lead 16.

From the above description of the shunt, it will be recognized that as the switch is actuated from its direct-connection position to its by-pass position, there is no interruption of current flow from the feed cable 6 to the load cable 7; the blade 9, before it escapes the clip I0, engaging the wiper 18 so that when such escape takes place a circuit-at less than full feed volate-is established through the resistor 23 to the booster transformer 15 (to pre-load the same), and thence to said load cable 7. Then, after the blade 9 initially engages clip 14, said blade escapes the wiper l8 and makes full engagement with clip I4 whereby the shunt is dropped out, the by-pass circuit is completed to the transformer, and the latter is energized directly from the feed cable 6.

From the foregoing description, it will be readily seen that there has been produced such a booster transformer switch as substantially fulfills the objects of the invention, as set forth herein.

I claim:

i. A pole-mounted switch adapted for use in connection with a feed cable, a load cable, and a booster transformer; comprising a mount, a pair of insulators secured to and projecting from the mount, one insulator being rotatable and the other insulator non-rotatable, arms on such insulators extending to outer end terminations normally in adjacent relation, a blade on the outer end of the arm corresponding to said one insulator. a clip on the outer end of the arm corresponding to said other insulator, the blade normally engaging in the clip but being disengagable therefrom upon part-circle rotation of said one insulator in a predetermined direction, the feed cable being connected to said one insulator and the blade, the load cable being onnected to said other insulator and the clip, a third insulator secured to and projecting from the mount in spaced relation to said pair of insulators, a supporting arm on and extending from the third insulator, a separate clip on such supporting arm and disposed thereby for engagement by said blade upon such part-circle rotation of said one insulator and resultant swinging of the blade away from said first-named clip, there being a by-pass circuit leading from said separate clip to the load cable, the booster transformer being interposed in such by-pass circuit, one bracket supported from said third insulator, a second bracket disposed in spaced relation to said one bracket, a dielectric rod fixed with and spanning between such brackets, a wiper secured in connection with said second bracket and positioned for contact by the blade during said swinging thereof, the wiper being formed and disposed so that the blade, upon such swinging thereof, makes contact with the wiper before disengagement from said firstnamed clip and thereafter makes contact with said separate clip before disengagement from said wiper, a resistor connected to and spanning between said brackets, and means providing electrical connection between said one bracket and the booster transformer.

2. A pole-mounted switch adapted for use in connection with a feed cable, a load cable, and a booster transformer; comprising a mount, a pair of insulators secured to and projecting from the mount, one insulator being rotatable and the other insulator non-rotatable, arms on such insulators extending to outer end terminations normally in adjacent relation, a blade on the outer end of the arm corresponding to said one insulator, a clip on the outer end of the arm corresponding to said other insulator, the blade normally engaging in the clip but being disengagable therefrom upon part-circle rotation of said one insulator in a predetermined direction, the feed cable being connected to said one insulator and the blade, the load cable being connected to said other insulator and the clip, a third insulator secured to and projecting from the mount in spaced relation to said pair of insulators, a supporting arm on and extending from the third insulator, a separate clip on such supporting arm and disposed thereby for engagement by said blade upon such part-circle rotation of said one insulator and resultant swinging of the blade away from said first-named clip, there being a by-pass circuit leading from said separate clip to the load cable, the booster transformer being interposed in such by-pass circuit, a shunt comprised of a wiper positioned for contact by the blade during said swinging thereof, and a shunt circuit extending from the wiper to the booster transformer.

3. A switch, as in claim 2, in which the wiper is formed and disposed so that the blade, upon such swinging thereof, makes contact with the wiper before disengagement from said firstnamed clip.

4. A switch, as in claim 3, in which the wiper is formed and disposed so that the blade, upon such swinging thereof, makes contact with said separate clip before disengagement from said wiper.

5. A switch, as in claim 2 including a resistor interposed in such shunt circuit.

6. A switch, as in claim 2 in which the wiper is formed and disposed so that the blade, upon such swinging thereof, makes contact with the wiper before disengagement from said firstnamed clip and thereafter makes contact with said separate clip before disengagement from said wiper,

. A switch, as in claim 6, Including a resistor interposed in such shunt circuit.

i i i Q III

Claims

1. A pole-mounted switch adapted for use in connection with a feed cable, a load cable, and a booster transformer; comprising a mount, a pair of insulators secured to and projecting from the mount, one insulator being rotatable and the other insulator nonrotatable, arms on such insulators extending to outer end terminations normally in adjacent relation, a blade on the outer end of the arm corresponding to said one insulator, a clip on the outer end of the arm corresponding to said other insulator, the blade normally engaging in the clip but being disengagable therefrom upon part-circle rotation of said one insulator in a predetermined direction, the feed cable being connected to said one insulator and the blade, the load cable being onnected to said other insulator and the clip, a third insulator secured to and projecting from the mount in spaced relation to said pair of insulators, a supporting arm on and extending from the third insulator, a separate clip on such supporting arm and disposed thereby for engagement by said blade upon such part-circle rotation of said one insulator and resultant swinging of the blade away from said first-named clip, there being a by-pass circuit leading from said separate clip to the load cable, the booster transformer being interposed in such by-pass circuit, one bracket supported from said third insulator, a second bracket disposed in spaced relation to said one bracket, a dielectric rod fixed with and spanning between such brackets, a wiper secured in connection with said second bracket and positioned for contact by the blade during said swinging thereof, the wiper being formed and disposed so that the blade, upon such swinging thereof, makes contact with the wiper before disengagement from said first-named clip and thereafter makes contact with said separate clip before disengagement from said wiper, a resistor connected to and spanning between said brackets, and means providing electrical connection between said one bracket and the booster transformer.

3. A switch, as in claim 2, in which the wiper is formed and disposed so that the blade, upon such swinging thereof, makes contact with the wiper before disengagement from said first-named clip.

6. A switch, as in claim 2 in which the wiper is formed and disposed so that the blade, upon such swinging thereof, makes contact with the wiper before disengagement from said first-named clip and thereafter makes contact with said separate clip before disengagement from said wiper.

7. A switch, as in claim 6, including a resistor interposed in such shunt circuit.