US2551772A - High-tension interrupting device - Google Patents

Description

y 1951 A. THXBAUDAT 2,551,772

HIGH-TENSION INTERRUPTING DEVICE Filed July 21, l 2 Sheets-Sheet l May 8, 1951 A. THIBAUDAT 2,551,772

HIGH-TENSION INTERRUPTING DEVICE Filed July 21, 194'. 2 Sheets-Sheet 2 I/7Ve/775k 596 /7. TmAQM/J Patented May 8, 1951 UNITED STATES PATENT OFFICE HIGH-TENSION INTERRUPTING DEVICE Application July .21, 1947, Serial No. 762,369 In France May 21,.1946

Section 1, Public Law 690, August 8, 1946 Patent expires May 21, 1966 10 Claims.

In the practical construction of high tension interrupting devices designed to interrupt mod. erate currents, such as for example disconnecting switches operating under load or circuit interrupters with moderate interruption power, it is necessary to obtain on one hand a rapid separation of the contacts and on the other hand a considerable spacing between the contacts in the completely open position. The first of these-two conditions is justified by the requirement-to reduce the duration and energy of the arcs and to accelerate the extinction thereof and it requires important acceleration forces while the second, justified by considerations of security, causes important forces to act throughout the entire length.

It therefore results that these devices exert ard acc 'nulate at the closing operation very considerable quantities of mechanical energy producing heavy strains in the control elements and in the devices themselves, rendering. difficult their manipulation, bringing-about violent shocks which risk damaging the insulators, producing dangerous reboundings. etc.

On the other hand the control of suchswitches is to be effected through the intermediary of insulating elements subjected to bending or torsional strains which are, as is known, undesirable. These disadvantages are particularly troublesome in the case of air blast switches, and the resent invention, also applicable to nonblowing devices, has. for an object avoiding these disadvantages by an improved arrangement wherein the rapid movement of the movable contacts, the action of the air blast and the general method of operation, all factors which favor. the rapid extinction of the arcs, are only acting during a period which is relatively short compared to ti?" entire duration of. the disconnection.

The invention also has for an object increasn the breaking power of pneumatic disconnec- 11 devices operating without a separated compressor, simplifying their construction and permitting their operation with relatively high tensions.

A. further object of the present inventionis to A- further object of the invention is to provide means whereby the first movement is a rapid rectilinear translation, suificient for the complete interruption of the controlled circuit, while the second is a rotation of the movable parts. When pneumatic extinguishing is applied it preferably takes place'only during the first movement.

A still further object of the invention is to avoid not only the disadvantages indicated above but also secure several new advantages which will beset forth below in the description of the structural examples which relate to disconnecting switches operating under load and circuit breakers having an are blowing system'with' concentric channels operating without separate-compressors.

Other objects of the invention will appear from the description which follows describing various possible modifications.

In the drawings, wherein similar reference characters indicate like parts, Fig. 1 is aside'elevational view with parts in section of one form of the invention showing the contacts in closedposition.

Fig. 2 is a side elevational viewwith parts in section showing the position of the elementsat the termination of the first translational movement for securing the actual interruption of the circuit.

Fig. 3 is a view similar to-Fig. 2 illustrating the position'of the elements in the completely open or safety disconnection position.

Fig. 4 is a partial cross sectional view on a larger scale of the contacts.

5 is a side elevational view with portions broken away and with a partial wiring diagram of a modified construction, and

Fig. 6 is aviea similar to Fig. 5 of a still further modification.

Referring to Fig. l, theporcela-in insulator I supports the group of fixed contacts 2 comprising the main contacts 3 and the resilient interrupting contact :3 shown in Fig. 4. The porcelaininsulator 5 supports the pivot 6 for the movable elements. These elements are formed essentially by a metallic tube '5 closed by a plug 1A and carrying the piston 23 as well as the movable cylinder 2 which may be displaced with relation to the piston 8.

Preferably the. length of the cylinder 9 is, rela tively small comparedto its diameter. The/cylinder is constantly urged towards the pivot; 6 by a strong concentric spring it whose-. J-Pperend. is attached to an enlargement I I provided-upon the 3 upper portion of the cylinder. The lower end of the spring iii is attached to the ring i2 which is fixed by two cars 52A to the common pivot 6.

The cover 9A of the cylinder 9 (Fig. 4) carries the movable contact it of tubular form which cooperates with the main contacts 3. At the interior of the tubular contact l3 whose end i3 may be made of an insulating material as shown is the conducting tuce it whose upper end i l of reinforced construction cooperates with the re silient interrupting contact The contact 4 carrying a guide rod ll has fixed thereto the insulating element t whose lower surface is in contact with the end it of the tube 13. The elements l, i" and d are urged downwards by a compression spring as shown; the downward movement of the contact 4 is limited by a stop upon the upper end of 4".

The conducting tube it is fixed to the elements ii and it. It has at its lower portion some longitudinal slots [5, Fig. 1, while the tube I has in the neighborhood of these slots some apertures 55 which open into the extension ll of the cylinder 9 arranged to'slide along the tube '5.

The extension ll carries two hinges l8 (Figs. 2 and 3) to which are attached two links 59, connected to the upper ends of the two angular levers whose lower ends are driven by the insulated connecting rod 2i. This connecting rod is actuated by an appropriate control mechanism not shown, or by hand.

The whole device is connected to the controlled circuit by the leads M and N fixed upon the terminals m and n.

In order to simplify the drawing there has not been shown thereon the usual means such as flexible connections, the sliding contacts, etc., for transmitting heavy currents across the different elements'of the apparatus.

The operation of the apparatus may be carried out by hand as a disconnecting switch or automatically as a circuit breaker. In order to describe its operation the first case is assumed. The movable elements occupying the completely opened position shown upon Fig. 3, a lever or wheel (not shown) is manually operated to strain a spring (not shown) and to move the insulating connecting rod 2| towards the right.

The lever 29 passes from the position A to the position B and all the movable elements swing freely as a unit towards the axis EB (Fig. 3) to reach the position shown upon Fig. 2. In this position the rotation of the tube i is stopped by the abutment 22 provided upon the lower porcelain support 5. This rotation which has no resistance to overcome takes place slowly and its termination by the abutment 22 carried out without shock.

Then the operating lever is turned by hand or by a control wheel (not shown) in the opposite direction which liberates the spring (not shown) mentioned above and this spring rapidly moves the angular lever 20 into the position C. The toggle joint l9, 2!] straightens and raises the hinges liiwith the cylinder 8, it which slides upwardly along the tube 7 while stretching the spring IS. The end it of the contact tube i3 contacts the element 4' the end Hi of the tube It contacts the resilient contact i. The elements 4 and i are raised and the tube i3 penetrates into the assemblyz while establishing the definite connection with the main contacts 3 (Fig. 1).

In the case of the manual control assumed above the toggle joint i9, 2%] passes preferably slightly past its dead point and the apparatus is in its stable closing position. In order to unlock it suffices to break the toggle.

In the case of automati control the angular lever 28 is preferably moved into the position C which is adjacent the position D of the dead point but without passing it. The apparatus then tends to open automatically and the insulating con" necting rod 2! is subjected to a small compression force. It may then be retained in this position (shown upon Fig. 1) by an appropriate looking device which may be unlocked by hand, by a relay, by interrupting a control circuit or by any other means.

The control mechanism of the insulating connecting rod 2i may comprise any known means which will secure a free tripping.

In order to facilitate the relative movement of the cylinder 9 with relation to the piston 8 during the closing operation, appropriate pneumatic elements such as suitable inlets or valves (not shown) are provided and are arranged to open during the upward movement of the cylinder 9 and prevent any pneumatic braking at closing. By way of security any appropriate locking means such as cams, pawls, etc., may be provided to prevent the premature straightening of the toggle joint 29, I9 during movement through the course A-B. This precaution is not indispensable since the correct succession of movements is assured through the considerable force of the spring H] which only comes into play during movement through the course B-C.

The unlocking is brought about according to this case, either by a slight displacement towards the left of the insulating connecting rod 2! when the dead point of the toggle joint has been passed during the course of closing or by the unlocking of the locking device (not shown) when the dead point has been reached.

During the circuit interruption the apparatus passes quickly from the position of Fig. 1 to that of Fig. 2. During the rectilinear translational movement, the lever 26 passes from position C to position B, the cylinder 9 urged by the spring it) moves downward and the outside tube 13 leaves the main contacts 3 after which the tubular contact Hi separates from the resilient interrupting contact 4 producing the interruption arc.

At the beginning of this movement the elements 4 and 4' follow through a certain distance the elements It" and M so that the upper openings of these movable elements remain temporarily closed. When the elements 4 and t are finally stopped in the position shown upon Fig. 2 by the abutment provided upon the rod i, the air compressed at the top of the piston 8 escapes through the annular channel between the tubes l3 and M (Fig. 4) while the lowering of pressure created under the piston 8 sucks the surrounding air through the tube M, the slots 15 and the apertures 16. as shown by the arrows upon Fig. 4.

These slots 15 are provided in order to maintain open the apertures 56 when the cylinder 9 and its inner tube M are in the lowest position, so that the space under the piston 8 is always in communication with the opening of the contact element M.

Experience shows that with this blowing method, as well as with simplified modifications thereof, the arc is quickly extinguished during a relatively short translation, which permits the use of a small cylinder 9 and consequently small and noncumbersome movable elements.

assume:

.This'rapid interrupting :movement being achieved; it lliS followed .by: the further rotation of the lever towards.the' position A: and all the .:movable elements return to the complete opening position. shown upon Fig. 3. Thisdisconnectingi movementtakes place at reduced speed and it is therefore accomplished without shock and without exposing theporcelain support 5 'to strains.

The voltage of the controlled circuits and the interrupting power of the interrupting :devices:

above set forth may be increased substantially by theuse of two or more devices analogous to those described above;- it is also possible to improve their performance by appropriate interrupting resistances.

The improved'means secure in a simple and economical way autonomous circuit .interrupters with. self compression; that is; operating without any special source ofcompressed air and nevertheless. havinga quite. high interrupting; power. Upon Fig. 5' there isshownan interruptor-with: selfl compression comprisingtwo movableequipments' connected in series and analogous to -those described above. In order to simplify the drawing there has not been shown thereon. either the operating elements of the movable elements or the resilient elements,.such as the springs which actuate the blowing means. All of-these elements may be arranged as set-forth above or inany other equivalent way.

The equipment shown comprisestwo fixed contact elements 2| and 22 supported by the insulators 23 and 24 andconnected to theouter. leads 25 and 25. These two fixed elements may com!- prise contacts of-. any nature, rigidor resilient, and particularly appropriate interrupting contacts,. schematically shownat 2| and 22.

They cooperate with. two movable. contact arrangements 21 and 28having suitable blowing means of. any .nature, supported by the movable cylinders 29- and. 30. These latter arepreferably of relatively large diameter to secureduring a relatively short distance with relation totheir pistons 3| and 32 suficient. compression or the inclosecl air.

The relative displacement of' the cylinders 29 and 3D.with relation to the pistons 3| and 32 is taken care of by. elastic means such as springs similar to those of Fig. l which have not been shown. These means urge. the two cylinders towards. one another when they have been. freed by any desired unlocking system.

The pistons 3| and 32 V are connected by a pivotally mounted support 33 mounted upon the pivot 34 and the. insulator '35. A resistance 36 may be connected as shown between'the movable elements and one of the terminal connections. Fig. 5 shows the apparatus in the locked position irr'which the circuit is closed and the opening means such as the springs mentioned" above are strongly strained.

In order to effect interruption, the opening means are released which rapidly displaces the cylinders 29 and withtheir tubular contact elements 21' and 23 towards the pivot 34. At the start of their travel the elements 21 and'28 are followed by'the resilient contact elements 2 l and 22' and the air filling the cylinders 29' and 30 is subjected to a rapid. compression'by the pistons 3| and: 32 which remain for the moment immovable.

Thecontacts' 2| and 22. are then stopped while the elements 21 and. ZS-continue their verticaltravel andJthe -arcs which. result are cili- 6; ciently" blown out by the compressed air. 11712517.- When :adefinite. extinction." of the: arcsyisz; thus 7 obtained during a relatively short rectilinear travel-of thecontacts 21. and 28:.thexsupport33 effects a rotation in clockwise direction: to occupy thedisconnecting position FF" in which the movable elements occupy the position shownv by dotted lines.

When aniinterrupting resistance 36- is used'one. of the arcs is shunted by the resistancewhich isacting'usefully' during the separation of "the corresponding'contacts Hand 22 in orderito damp the. oscillations'iofi the recovery "voltage and to "increase" if necessary the. interrupting power. The shunted arc maybe started a'little: before the nonshunted arc.

.In the modification shown upon Fig; 6 the pistons 3|: and'32tare supported bythe' separate supports 31 and 38 pivoted at. 39 and). The

' pivot. 39 is provided upon the .fiXed contact element 22 and the. pivot 40 as well as the terminal connection 2 B are supported by. thei'insulator. 4 l

The resistance. 36' maybe connected 'between 22j and 40 for example.

The-two movable units 27,29, 31. and 23, 30.38, carry out in 'thisrarrangement separate imovements in order to occupy finally. the disconnecting positions shown in dotted lines'at G andIG'.

The mechanism designed for producing the successive movements of" the movable elements may be analogous to that of Figs. 1 to 3 or bearranged in any other appropriate way. For: example, thecorrect succession of the-various interrupting and disconnecting movements" may be secured with the aid of appropriate cams and thereby eliminate the springs which are attached directly to the movable cylinders. -A resilient element for actuating the cylinders for the first movement corresponding to the interrupting-of the arcs may be in this case locatedin th'ecom moncont-rol mechanism and. may be arranged to intervene only during the corresponding movement.

In place of displacing the cylinders 29 and. 30 with relation tothe pistons 31 and 32, the pistons may be displaced to-secure the extinctionof the arcs by a' rectilinear. movement of the contacts 2 l andi22 so-as to space them from the blowing elements 2'! and 28 afterwhi'ch the disconneciion rnay be secured by an appropriate displacement of the elements 2| and 22 orby a rotation of the cylinderas' has been set forth above.

Other combinations of two or more move ments may be provided and other modifications of the means described may thereby be obtained.

It is also obvious that the blowing method described may be modified. .For example, cylinders and pistonsmay be eliminated or replaced with the action of .a gas. produced in a. known manner by suitable bodiesunder. the efiect of thearc, etc.

In place of. a. rapid rectilinear movement for the actual. interruptioniollowed by a slow rota? tive movement for the disconnection, two or more successive. rectilinear movements may also be used. One movement with the blast may be rapid, for example. and the other slow. Also two or more successive rotative movements, or the interruption may be carried. out by rotation. and the disconnectionby translation. It is obvious that other vmodificationsare possible.

The apparatuses described and their .modificationsarcay be used. and arranged in anyapprop-riateway according to the conditions. of usein order. to. operate;- forexample,- as. disconnecting:

I! d switches operating under load or as automatic circuit interrupters with a reasonable interruptionpower. The invention presents particularly the following advantages.

The mechanical forces are only applied during a portion of the travel (through BC) which reduces by a very large proportion the mechanical energy accumulated and facilitates operation of the apparatus.

The control is carried out through the intermediary of an insulating connecting rod 2! which is only exposed to traction efiorts or compression which permits lightening the construction and securing a greater security.

The porcelain supports for the movable elements are not subjected to violent shocks which also increases the security of operation.

The control elements shown and not shown such as the connecting links, locking devices, etc., may be diminished in weight and simplified.

The pneumatic blowing elements being reduced in weight and oumbersomeness in that they only come into action during a short interruption'travel permit the inertia of the movable elements to be reduced and the circuit interruption to be rapid.

The blowing elements having an appropriate diameter and being located very close to the contacts, the blowing action acts very rapidly and upon separation of the contacts, it attains full efiiciency.

In the following claims the term disconnection means the separation of the contacts to a safe position such as shown in Fig. 3.

I claim:

I. A high tension circuit interrupter comprising a fixed contact and a movable contact, said movable contact comprising a pivotally mounted support, a piston on said support, a cylinder for said piston slidable on said support, coaxial tubular members fixed to said cylinder forming the contact elements cooperating with said fixed contact, means for moving said cylinder and contact elements toward and away from said fixed contact in a rapid rectilinear movement to bring about the actual interruption and closure of the-circuit, said movement causing a relative movement between said piston and cylinder placing air under pressure which is expelled through said tubular members for extinguishing the are formed upon the interruption of the circuit and means for swinging said support and associated elements to disconnection position at the termination of the rectilinear interrupting movement.

2. A high tension circuit interrupter comprising a fixed contact and a movable contact, said movable contact comprising a pivotally mounted support, a piston on said support, a cylinder for said piston slidable on said support, coaxial tubular members fixed to said cylinder forming the contact elements cooperating with said fixed contact, resilient means interconnecting said cylinder and support, toggle means for moving said cylinder and contact elements to closure position and thereby placing said resilient means under tension, means for releasing said toggle means so that said cylinder is retracted rapidly along said support by said resilient means said movement causing a relative movement between said piston and cylinder placing air underpressure which is expelled through said tubular members for extinguishing the are formed upon the interruption of the circuit and means for swinging said support and associated elements to disconnection position at the termination of the rectilinear interrupting movement.

3. A high tension circuit interrupter comprising a fixed contact and a movable contact, said movable contact comprising a pivotally mounted support, a piston on said support, a cylinder for said piston s'lidable on said support, coaxial tubular members fixed to said cylinder forming the contact elements cooperating with said fixed contact, resilient means interconnecting said cylinder and support, toggle means for moving said cylinder and contact elements to closure position and thereby placing said resilient means under tension, means for releasing said toggle means so that said cylinder is retracted rapidly along said support by said resilient means said movement causing a relative movement between said piston and cylinder placing air under pressure which is expelled through said tubular members for extinguishing the are formed upon the interruption of the circuit, the inner coaxial member of said coaxial tubular members having communication with the suction side of said piston so that a suction is also exerted to extinguish said arc and means for pivoting said support and associated elements to disconnection position at the termination of the rectilinear interrupting movement.

l. A high tension circuit interrupting and disconnecting device comprising a fixed contact and a co-operating movable contact unit, said contact unit being formed by a pivotally mounted support, a piston fixed upon said support, a cylin der for said piston slidable on saidpiston, coaxial nozzle members carried by said cylinder and forming the movable contact proper and means for positively separating said movable contact from said fixed contact first in a rapid rectilinear translation to bring about the actual interruption of the circuit by a rapid contact separation and by an air blast resulting from the relative movement of said cylinder, and then in a slower rotation of said support and of the associated contact unit in order to further increase the said contact separation.

5. A high tension circuit interrupting and disconnecting device having a fixed contact and a cooperating movable contact unit, said unit comprising a pivotally mounted support, a piston on said support, a movable cylinder cooperating with said piston, coaxial tubular members fixed to said cylinder and forming a movable contact, resilient elements interconnecting said cylinder and support, positive mechanical means for moving said cylinder with the said associated movable con tact into the closed position and thereby placing said resilient elements under tension and means for releasing said resilient elements, whereby said movable contact and cylinder are first retracted rapidly along said support producing air blasts through said tubular members for extinguishing the are formed upon the separation of contacts, said mechanical means being arranged for producing after said retracting movement a rotation of said support and of its associated elements in order to further increase the separation of said contacts.

6. A high tension circuit breaking and disconnecting device comprising two fixed contacts and two cooperating movable contacts connected in series, each of said movable contacts comprising a pivotally mounted support, a piston on "said support, a cylinder for said piston slidable on said support, coaxial tubular members fixed to said cylinder forming the contact elements cooperating with said fixed contact, resilient means interconnecting said cylinder and sup-port, toggle means for moving said cylinder and contact elements to closure position and thereby placing said resilient means under tension, means for re leasing said toggle means so that said cylinder is retracted rapidly along said support by said resilient means, said movement causing a relative movement between said piston and cylinder placing under pressure the air which is expelled through said tubular members for extinguishing the are formed upon the interruption of the circuit, the inner coaxial member of said coaxial tubular members having communication with the suction side of said piston so that a suction is also exerted to extinguish said arc, and means for pivoting said support and associated elements to disconnection position at the termination of the rectilinear interrupting movement.

7. A high tension circuit breaking and disconnecting device comprising two fixed contacts, two cooperating movable contacts and a pivotally mounted support carrying both said movable contacts, each of which comprises a piston on said supports, a cylinder for said piston slidable on said support, coaxial tubular members fixed to said cylinder forming the contact elements cooperating with said fixed contact, resilient means interconnecting said cylinder and support, toggle means for moving said cylinder and contact elements to closure position and thereby placing said resilient means under tension, means for releasing said toggle means so that said cylinder is retracted rapidly along said support by said resilient means, said movement causing a relative movement between said piston and cylinder placing air under pressure which is expelled through said tubular members for extinguishing the are formed upon the interruption of the circuit, the inner coaxial member of said coaxial tubular members having communication with the suction side of said piston so that a suction is also exerted to extinguish said are, and means for pivoting said support and associated elements to disconnection position at the termination of the rectilinear interrupting movement.

8. A circuit interrupting and disconnecting device comprising a movable contact including an axial conducting tube forming the contact element proper and an annular channel, positive mechanical driving means to effect during the circuit interruption a rapid arc interrupting translation of said movable contact, as well as a less rapid transverse disconnecting movement of the same contact, a cylinder supporting said movable contact, a cooperating piston, means for displacing said cylinder with respect to said piston during said translation only, and means for interconnecting respectively both parts of said cylinder with said conducting tube and said annular channel, whereby an air-blast and an air-suction are produced.

9. A high tension circuit interrupting and disconnecting device comprising a fixed contact and a cooperating movable contact structure including a tubuiar element, an axial conducting tube forming the contact element proper and an annular channel surrounding said tube, said movable contact having pivotally mounted support, a piston fixed upon said support, a movable cylinder for said piston, carrying said movable contact structure, the said tube being connecte: to one part of said cylinder and the said annular channel being connected to the other part or said cylinder, resi'iient members interconnecting said cylinder and support, mechanical means for positively operating said cylinder and movable contact to a position in which said resilient means are placed under tension and the circuit is closed, means for releasing said resilient members vhereby two successive movements are produced, the first being a rapid translation resulting in a separation of the contacts and producing an air blast through said annular channel and an air suction through said conducting tube in order to extinguish the arc, and the second being a pivotal rotation of said support adapted to increase substantially the separation of contacts obtained during the said translation.

16. A high tension circuit breaker comprising a fixed contact and a. cooperating movable contact, said movable contact comprising a pivotally mounted support, a piston on said support, a cylinder for said pistonslidable on said support, coaxial tubular members fixed to said cylinder forming the movable contact elements cooperating with said fixed contact, means for moving said cylinder and tubular members away from said fixed contact in a rapid rectilinear movement to bring about the actual opening of the circuit, means upon said fixed contact adapted to close said tubular members on a part of said rectilinear movement, whereby the air filling said cylinder is compressed until said tubular members are opened and said compressed air is expelled through said tubular members for extinguishing the arc of interruption of the circuit, and means for swinging said support and associated elements to disconnection position at the end of said rectilinear movement, whereby the distance between said cooperating contacts is further increased.

ALBERT THIBAUDAT.

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

UNITED STATES PATENTS Number Name Date 525,332 Card Sept. 4, 1894 1,563,833 Christensen Dec. 1, 1925 2,039,838 Saudicoeur May 5, 1936 2,264,862 Scheuermeyer Dec. 2, 1941 2,279,024 Korndorfer Apr. '7, 1942 2,286,131 Wallace et al June 9, 1942 2,429,311 Gay Oct. 21, 1947

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