US1781260A

US1781260A - Electric switch

Info

Publication number: US1781260A
Application number: US277030A
Authority: US
Inventors: Wenzlawski Karl Emil
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-05-11
Filing date: 1928-05-11
Publication date: 1930-11-11
Anticipated expiration: 1947-11-11

Description

NOV. 11, 1930. w z w 1,781,260

ELECTRIC SWITCH Filed May 11, 1928 '2 Sheets-Sheet 1 K5. WEN z LAW-3K! INVENTOR.

BYdQW/Q ZXZWL Min ATTORNEY -'NO 1930. K. E. WENZLAWSKI 1,781,260

ELECTRIC SWITCH Filed May 11, 1928 2 Sheets-Sheet 2 FIG. 5

ICE. WEN ZLA NSKI INVENTOR.

[Al ATTORNEY latented Nov. 11, 1930 PATENT OFFICE KARL EMIL Ji'llillflIZLAVVSKI, F GALVESTON, TEXAS ELECTRIC SWITCH Application filed May 11, 1928. Serial No. 277,030.

My invention relates to electric switches for closing electric light or power circuits.

t is particularly adapted for use in light circuits in buildings.

My device is designed to prevent danger in case of a short circuit in the lighting circuit of a building. It is a more or less common occurrence when a fuse is blown out in the lighting circuit due to overload, or to lightening, or other causes for the attendant in charge of the building to substitute a new fuse'in place of the blown out one and again close the circuit. Sometimes a proper fuse is not available and coins, or nails, or pieces of wire are substituted for the fuse. If it happens that there is a short circuit in the building, there is then danger of tire where the short circuit occurs.

It is an object in my invention to provide a switch for the control of building circuits or" this kind wherein provision is made to prevent the closing of the switch when there is a short circuit in the building.

The invention consists inthe provision of an electrically operated device which willbe actuated to move into the path of the switch and prevent its closing where the resistance of the lighting circuithas been cut out by means of the short circuit.

Referring to the drawing herewith, Fig. 1 is a diagrammatic plan view of a swtich emboc ying my invention. Fig. 2is an elevation of the stop arm whereby the switch is pre vented from closing, parts of the apparatus being removed for greater clearness. Fig. 3 is a detailed view of the electromagnet and the operating arm whereby the stop mechanism is operated.

I contemplate the use of my invention with the ordinary type of two blade knife switch used in the lighting circuit of houses and other buildings. I have shown a switch employing two blades 1 and 2, hinged to terminals 3 and 4 respectively, the free ends of said blades being connected by an insulating member 5 having a handle 6. On the forward side of the handle is a short arm 3? projecting into the path of a stop member which will be later described.

The switch is mounted upon a base in the usual manner. The main light circuit 8 is connected through fuses 9 to the posts 10 audit) and it will be seen that there are two

posts

10 and 10 connected with the contact members 11in which the blades 1 and 2 of the switch engage when in closed. position.

The circuit from the post 10 is connected at 12 to a transformer 13 by means of which the voltage is materially reduced. The opposite post 10 is connected by a wire 14 to the terminal 12 through the transformer.

The circuit from the transformer is carried through a wire 15 at one side to a spring arm 16, the shape of which is best shown in Fig. 2. It extends upwardly and has a curved contact member 17 at its upper end which extends in to the path of the blade 2 of the switch and contacts therewith when the blade is being moved to or from its closed position.

The other wire 17 of the auxiliary circuit is connected through an electromagnet 18 to a post 19 at the terminal 3 of the house circuit. 7 The electromagnet 18 is of ordinary construction and is adapted to move a arm 20. Said spring arm is mounted upon a post 21 on the inner side of the base 7 and is connected through an arm 23 of magnetic material which extends forwardly of the base and is connected at its forward end to a link 2:2. This is a pivotal connection and the lower end of said link 22 is pivotally'connected at 23 with the arm 24: of a bell crank lever 25, pivotally supported upon a pin 26 mounted upon a block 27 on the base. The upper arm 28 or" the bell crank lever extends normally upward and has a wide notch or recess 29 therein, the sides of said notch being beveled outwardly at 30. This arm is intended to act as a stop to engage the arm 87 upon the handle as previously noted.

In the operation of this device the auxiliary circuit is regulated by the transformer 13 to be of such small voltage that when the light circuit through the wires 31 is connected in the usual manner through the resistance of the lights the current will be of insuilicient strength to actuate the electromagnet l8. lVhen, however, the lighting circuit is grounded in some manner the resistance of spring the auxiliary current will be suflicient to actuate the magnet to move the stop member. 7 Thus when there is a short circuit formed in the lighting circuit 31 and a fuse has been blown out the operator may replace the fuse and attempt to close the switch. If a short circuit still remains in the house circuit the current through the magnet in the auxiliary circuit will be of sufiicient value to energize the magnet to move the arm 23 downwardly. Thisc will, through link 22, move the arm 25 ahct throw the stop member 28 into position directly beneath the arm 37 upon the handle and -prevent its closing. It is to be noted that the auxiliary circuitis not closed to energize the magnet until the blade 2 of the switch contacts with the member 16. This will throw thestop memberiinto position and hold it in that'position until the stop arm37 engages therewith. It will hence be impossible to close the switch until the short circuit in the house lighting circuit has been repaired. I, v The advantage of this arrangement will be obvious to those skilled in the art. The danger from fire through short circuits in a building will be practically eliminated. 1 9 Having thus described my invention, what a'ed'claim as new is: i 1 a 1. A safety syy-itch omprising a two blade switch adapted ttrcojnnectthe two.w1r es or a main light circuit to two terminals of a house lighting circuit, in combination with anauxiliary circuit from said light wires, a transformer in said auxiliary circuit, a resilient contactpositioned in the path of movement of one of said switch blades, connected with one of the'wires of said auxiliary circuit, the other through an ele'ctromagnet to the terminal of the house 'circuit'remote from the said re Y silient contact member, and means actuated by said electromagnet when said'switch contacts with saidresilient contact to prevent short circuit on the house circuit.

. 2. A safety'switchincluding atwo blade switch adaptedto connect the wires of a main incombination with an auxiliary circuit of comparativelysmall voltage, said auxiliary circuithaving one terminal thereof forming a wiping contact with one blade of said other terminalof said auxiliary circuit connecting to the termmal of the other blade of said switch,- an electromagnet in said auxiliary circuit, and means actuated by said .60 electromagnet to moveinto thepath of said switch and prevent its closing when there is ashort circuit in said circuit.

y 3. A safety switch including atwo blade switch adaptedtoconnect thewires of a main circuitto the'terminals of a house-lighting the lights is cut out so that the strength of of said auxiliary wires being connected the closing of said switch when there is a circuit to the terminals of a lighting circuit switch whensaid blade is partlyopened, the

circuit in combination with an auxiliary circuitof comparatively small voltage said auxiliary circuit having one terminal thereof forming a wiping contact with one blade of said switch when said blade is partly opened, the other terminal of said auxiliary circuit connecting to the terminal of the'other blade of said switch, an electromagnet in said auxiliary circuit, and an arm operated by said electromagnet, a hinged stop member, and'a' said arm whereby said stop member may be moved into the path of said switch and prevent its closing,

.4. A safety switch for use in a house lighting circuit, including an auxiliary circuit of '75 7 connection between said stop member and comparatively small voltage, connected in said house circuit, said auxiliary circuit having one terminal positioned to engage a blade of said switchwhen said switch is moving to closed position, an electromagnet in said auxiliary circuit, and a stop arm operated by said magnet to move into the path of said switch when there is a short circuit in said house circuit, to prevent the closing of said switch.

5. A safety switch for use in a'house lighting circuit, including anauxiliary circuit of comparatively small voltage, connected in said circuit, sai'dauxiliary circuit having one terminal positioned to engage a blade of said switch when said switch is moving to closed position, an electromagnet in said auxiliary circuit, and an arm operated by said electromagnet when said house circuit is short circuited and a stop member moved by the operation ofsaid arm into thepath of said switch to prevent its closing. I Y Y.

6. A safety switch for use in a house lighting circuit, including an auxiliary circuit of comparatively smallrvoltage, connected in said house circuit, said auxiliarycircuit'having one terminal positioned to engage a blade of said switch when; said switch is moving to closed position, an electrically operated device in said auxiliary circuit adaptedto be energized only when the said house circuit is short circuited, and a stop arm adapted to be moved by said electrically operated'device to prevent closing of said switch when said switch engages said terminal of said auxiliary circuit. i I w In testimony whereof I hereunto'afix my signature this 5th day of May, A. D. 1928.

KARL EMIL lVENZLAl/VSKI.