US2510713A - Electric time switching system - Google Patents

Description

June 1950 G. D. OLSSON ELECTRIC TIME SWITCHING SYSTEM Filed NOV. 4, 1944 mm, mm

Ala [#7019 Patented June 6, 1950 LSMJEE UNITED STATES FATEN'T OFFKCE 2,510.71}? ELECTRIC TIM'ESWITCHING sYs'rsM Gunn'ar Daniel'olsson, Sibelius-mi; Sweden Application November 4, 1944, SerialNo 561,97 1 In Swedcn'Septem'ber1151943 rename. (or-na sea) The present; invention relates to electric operating devices of the kindhavingo'ne or more contacts which; are opened or closed when the devices are switched in. An obje'ctoi the invention is to provide an improved constructionand arrangement 'ofthe releasing means in a device of this kind;- which new releasing-means is very sensitive and may; be actuated by an impulse of very short duration. Another object of theinvention isto'providean improved staircase time switehwvhichmay be switched in for twice as 16 atimeas normally. v

in embodiment of the invention is diagramally shown in the accompanying drawing. -ig=i isapl-an'view, partly shown as a diagramoi anelectric operating deviceembodying the inventien.- Figs. -2 and -3-;are;aplan view and aside view respectively of adetail of Fig. 1.

Referringto the drawing" Lisa base-plate on whicha fastening- 2 of insulating material and two catches (sand 3 formed as levers are mounted. The levers Band i are turnable about fixed pins Sit-and 38; respectively. Contact springst, 6, 1 and Sara mounted in thefastening-2. The two springs-sand '6 are-provided with contact means 9 which are in contact withone another in the normal position of; the springs, while the two othessprings 7 and 3 make-contact with one another via contactmeans- It. The spring 5 has an initial tension directed upwards (as shown in the drawing) and the spring 6 hasan initial tension directed downwards; Therspring i is a bimetallic-strip and is arranged to rest, in the no n-al position; ;against a shoulder of in- Se ting material. A heatcoil 4surrounds the bimetallic strip I, one end of said coil being connected with-the spring Send the other end with the minus pole of a source of current (not shown). The-springs -6 and 7 are provided with cooperating contact means I2 which, in the working position, are brought into contact'with one another. A pin ls of insulatin material is attached to the springwhich pin freely extends through openings in the springs 6 and EL On theother side of the spring 5 said pin is providedwith a plate M for holding; in thenoranal position, the contact means 9 in contact with each other.- The spring ii has an initial tension di-iected' upwards and rests, in the norniai po; sition, against the spring! at the contact means Hi. When the spring 1 moves upwards the spring 8' iollows after intofabutment withthe shoulder 1 i {the contact It being then opened.

The catches, sand 4 are adaptedtobe actuated bf'm'ans' of'tw'o draw springs i5 and H5 re- 2 spectively inounted on the base plate i. Said springs 15; it are adapted to hold the: turnable catches sand ii in the normal position shown in the drawing. Ihe catch 3 is provided near h ree w h a notch l. nio. wh the freeendsof the contact springs 5 and 6 project. The detent surface is provided for the spring 5 projects somewhat beyond the detent surface is provided for the spring 6., The catch 4 is provided with aishoulder 20 or the like adapted to cooperate with a roller 2! turnably mounted at the free end of the spring 7. For the turnahlemounting of. the roller 21 the spring I is provided with a slit '4! at its free end so that said end'is'forked. The prongs of the fork are rolled up so that they form bearings 42 for a pin 43 to which the roller 21 is attached.

In the drawing belowthe fastening 20f bridge 23 of insulating material is attached to the baseplate l by means of two screws 22; The bridge is provided at the right hand end with a fastening 2 supporting affiat spring 25. Said spring is at the free end provided with a fastening '25 of insulating material;' This fastening comprises two pins 2? crthe like, each of them being provid'ed with a groove, and is arranged to rest with itsedge 28 against thecatch 3 in the normal position. Atthe left hand end of the bridge there arearranged two metal pins 29 each connected with alug 3! Between these metal pins a pin si having groove is attached to the bridge 23. Round-this pin and round the pins}?! a very f ne electricallyconducting filament or resistance wire ez is stretched twice'to and fro, the ends of'which are'fastened in the pins 29 by means of which the current is supplied from the lugs 30. The filament 32, when it is cold, holds the spring 2% in the position shown in the drawin g. Du'e'to' the smallsectional area of the filament ajvery rapid heating and coolingof the same is obtained. If the filament is strong enough a single filament stretched between the mac ines can naturally be used. However, in order to obtain convenient connections the wir preferably, maybe drawn at least once to and fro.

The arrangement of the filament 32 on the bridge 23 serves to facilitate the mounting. In order to adjust in a simple manner the position iihe e se a rel to e a e the r e 23 is provided with oblong holes 33 for the fasten ins Scr ws V v the present case the embodiment shown and r b dre d s 'st c e i eswitch- The object to be operated is represented by '3? lamps 3 adapted to be lighted by means of push buttons 35 which return resiliently.

The method of operation of the operating means is as follows.

When one of the push buttons 35 is impressed the following circuit is closed:

the push button 35, the filament 32, the spring 5, the contact 9, the spring 6, The filament 32 is thus heated immediately and expends so that the spring '25 is able to release its tension and to impart to the catch 3 a motion away from the group of contact springs. The catch 3 turns clockwise so that the spring 6 is disengaged and, owing to its tension in a direction downwards, rapidly interrupts said circuit at 8. Then the filament 32 cools. During the continued movement of the spring 6 downwards it is brought into contact with the spring I at E2. When the filament 3'2 is cooled the spring 25 with the fastening 28 is set into its normal position. The catch 3 is retained in the pushedaway position by means of the spring 6, the free end of which resting against the straight part 36 of the lever 3.

Ihe contact l2 closes the following circuits:

the lamps 34, the bimetallic spring i, the contact l2, the spring 6, Thereby, the lamps 3 3 are lighted.

the heat coil Mi of the bimetallic spring I, the spring 8, the contact Hi, the spring l, the contact ii, the spring i5,

When the bimetallic spring 5 upon heating has reached such a tension that it overcomes the counter-tension of the spring it on the catch l, the roller 2i of the bimetallic spring 1 rapidly moves past the shoulder 26 while lifting the spring 5 and comes into a blockading position on the shoulder 29. l-Iereby, the heat current of the heat coil at the'contact It is interrupted and the spring 8 is lifted into a position in which it stands in front of the notch ll when the catch 3 through operation of the spring is is returned to the starting-position. When the bimetallic springs l is in the blockading position, the pin I3 is pushed up through the springs 5 and t in such a way as to provide clearance between the plate i i and the spring 5, the latter occupying such. a position that its free end rests against the upper detent surface iii of the notch ll.

When the bimetallic spring '5 cools, it tends to return to its normal position and when it has reached such. a tension as to overcome the blockading power of the spring l6 acting on the catch l, it rapidly moves past the shoulder 20 in the direction downwards (as shown in the drawing). At this moment the contact at it is interrupted by the spring 6 remaining in the notch H. The object to be operated is switched off and the starting position is again reached.

if the push-button 35 again is impressed while the bimetallic spring is still in the blockaded position and, thus, the contact means 9 are closed the filament 32 receives current via the same circuit, as mentioned hereinbefore. The spring 25 actuates the catch 3 in such a way that it will be turned clockwise, The spring 5 is free to move and its tension is released so that it is rapidly moved to rest against the plate M. The contact means 9 are opened and the current to the filament 32 is interrupted. The latter is cooled and the spring 25 is set into the normal position. The straight part ill of the 'catch 3 is now in contact with the free'end of the spring 5. When the bimetallic spring l is cooled and when it returns into the-normal position, the spring 5 is carried along by the pin it provided with the plate It so that the straight part 36 of the catch 3 by means of the spring i5 is moved into contact with the free end of the spring 6 which on its way downwards already has moved past the notch I! while the spring 5 falls into the same. The contact 12 is still closed and, thus, also the circuit of the lamps. When the bimetallic spring "I has reached the normal position it strikes the spring 8 at the contact it so that the heat coil of the bimetallic strip receives heat current. The bimetallic strip is thus bent upwards and the cycle described above is repeated. When the bimetallic spring is cooled and when it returns to the starting position the circuit of the lamps -is opened because the springs 5 and 6 have returned to their respective starting positions, the free ends of the same resting in the notch H. The device is now ready for a new operation.

Thus, it is clear from the aforesaid that the time during which the load is switched in may be approximately doubled by repeated impression of the push button 35 when the bimetallic spring has been heated. V

The accompanying drawing illustrates the operating means connected to a direct current circuit but owing to its fundamental construction said means may also be used for alternating current. V

The embodiment described above and shown in the drawing merely represents an example. It is clear that the constructional arrangement, especially with regard to the combination of the contacts, may be varied in diiierent manners without, therefore, departing from the principle of the invention. Should there exist different sources of c'urrentfor the operating current and the load, the circuits may, for example, be separated by attaching the lower part of the contact Q to a separate spring insulated from the spring 6 but mechanically connected thereto. In a similar manner the contact it may be arranged so that the heat coil of the bimetallic spring is separated from the load current. In a staircase time switch according to the invention, which can be switched in for twice as long a time as normally, it is possible to replace the filament by another releasing means of a kind known per se, forexample a magnetic means.

What I claim is:

1. An electric circuit controller including an actuating circuit connected to a source of voltage, comprising at least one switch in said circuit for momentarilyclosing said circuit, a stationary support, a resilient support, an electrically conducting thin filament forming a portion of said circuit and being stretched between said stationary support and said resilient support whereby the latter is held in a biased position, at least two pairs of cooperative spring contacts, the first of said pairs of contacts being connected in said actuating circuit, a controlled circuit including said second pair of spring contacts, a catch holding said spring contacts in a biased position in which said first pair of spring contacts is closed and said second pair of spring contacts is open, said catch being operable by said resilient support, so that upon closing said actuating circuit with a resulting extension of said filament, said catch is operated by said resilient support to release said pair of spring contacts to take up a position by their bias, in which position said first pair of spring contacts is open and said second pair of contactsis closed, and means returning said pairs of spring contacts to their biased position after a predetermined time, said means being operable in response to the closing of said second pair of spring contacts.

2. An electric circuit controller including an actuating circuit connected to a source of voltage, comprising at least one switch in said circuit for momentarily closing said circuit, a stationary support, a resilient support, an electrically conducting thin filament forming a portion of said circuit and being stretched between said stationary support and said resilient support whereby the latter is held in a biased position, a bridge on which said supports are mounted, a base plate carrying said bridge, at least two pairs of cooperative spring contacts, the first of said pairs of contacts being connected in said actuating circuit, a controlled circuit including said second pair of spring contacts, a catch mounted on said base plate and holding said spring contacts in a biased position in which said first pair of spring contacts is closed and the second pair of spring contacts is open, means for adjusting the position of said bridge on said base plate and the position of said resilient support relatively to said catch so that upon closing said actuating circuit with a resulting extension of said filament, said catch is operated by said resilient support to release said pair of spring contacts to take up a position by their bias, in which position said first pair of spring contacts is open and said second pair is closed, and means returning said pairs of spring contacts to their biased position after a predetermined time, said last mentioned means being operable in response to the closing of said second pair of spring contacts.

3. An electric circuit controller including an actuating circuit connected to a source of voltage, comprising at least one switch in said circuit for momentarily closing said circuit, a stationary support, a resilient support, an electrically conducting thin filament forming a portion of said circuit and being stretched between said stationary support and said resilient support whereby the latter is held in a biased position, at least two pairs of cooperative spring contacts, the first of said pairs of contacts being connected in said actuating circuit, a controlled circuit including said second pair of spring contacts, a catch holding said spring contacts in a biased position in which said first pair of spring contacts is closed and said pair of spring contacts is open, said catch being operable by said resilient support, a bimetallic strip returning said pairs of spring contacts to said biased position for engagement with said catch, a heating circuit for said bimetalic strip including said second pair of spring contacts, a third pair of spring contacts in said heating circuit, and a second catch preventing movement of said bimetallic strip until the tension of said strip, upon heating and cooling respectively of said strip, has reached a predetermined value sufiicient to overcome said second catch and to give said strip a snap movement from the cool position to a hot position and vice versa, the third pair of spring contacts being closed in the cool position of said strip and open in the hot position of said strip, and the second pair of spring contacts being closed in said hot position, so that upon closing said actuating circuit with a resulting extension of said filament, said first catch is operated by said resilient support to release said pairs of spring contacts to take up a position by their bias, in

which position said first pair of spring contacts is open and said second pair is closed to heat said bimetallic strip and to move it to the hot position and restore the engagement of said first catch with said first and second pairs of spring contacts and to open said second pair of spring contacts by the movement of said strip, after cooling, back to said cool position.

4. A staircase time switch including an actuating circuit connected to a source of voltage, comprising at least one push button switch in said circuit for momentarily closing said circuit, a stationary support, a resilient support, an electrically conducting thin filament forming a portion of said circuit and being stretched between said stationary support and said resilient support whereby the latter is held in a biased position, two pairs of cooperative spring contacts, the first of said pairs of contacts being connected in said actuating circuit, a controlled circuit including said second pair of spring contacts, a catch holding said spring contacts in a biased position in which said first pair of spring contacts is closed and said second pair of spring contacts is open, said catch being operable by said resilient support, a bimetallic strip returning said pairs of spring contacts to said biased position for engagement with said catch, a heating circuit for said bimetallic strip including said second pair of spring contacts, a third pair of spring contacts in said heating circuit, a second catch preventing movement of said bimetallic strip until the tension of said strip, upon heating and cooling respectively of said strip, has reached a predetermined value sufiicient to overcome said second catch and to give said strip a snap movement from the cool position to a hot position and vice versa, the third pair of spring contacts being closed in the cool position of said strip and open in the hot position of said strip and the second pair of spring contacts being closed in said hot position, so that upon closing said actuating circuit with a resulting extension of said filament, said first catch is operated by said resilient support to release said pairs of spring contacts to take up a position by their bias, in which position said first pair of spring contacts is open and said second pair of contacts is closed so as to heat said bimetallic strip and to move it to the hot position and restore engagement of said first catch with said first and second pairs of spring contacts and to open said second pair of spring contacts by the movement of said strip after cooling, back to said cool position, and means to prevent engagement of said first catch with said first and second pairs of spring contacts after a repeated releasing of said catch by closing of the actuating circuit in the hot position of said first catch to bring said second pair of spring contacts to remain in the closed position upon movement of said first catch to the cool position and to repeat the heating of said metallic strip.

GUN NAR DANIEL OLSSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,328,479 Baker Jan. 20, 1920 2,340,877 Hausler Feb. 8, 1945

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