US2875296A - Automatic circuit breaker - Google Patents

Automatic circuit breaker Download PDF

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Publication number
US2875296A
US2875296A US513842A US51384255A US2875296A US 2875296 A US2875296 A US 2875296A US 513842 A US513842 A US 513842A US 51384255 A US51384255 A US 51384255A US 2875296 A US2875296 A US 2875296A
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US
United States
Prior art keywords
bimetal
contacts
bimetal element
breaker
portions
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US513842A
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English (en)
Inventor
Enderli Ernst
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Weber AG
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Weber AG
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Filing date
Publication date
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H73/00—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism
    • H01H73/22—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism having electrothermal release and no other automatic release
    • H01H73/30—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism having electrothermal release and no other automatic release reset by push-button, pull-knob or slide
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
    • H01H71/10—Operating or release mechanisms
    • H01H71/12—Automatic release mechanisms with or without manual release
    • H01H71/14—Electrothermal mechanisms
    • H01H71/16—Electrothermal mechanisms with bimetal element
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H73/00—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism
    • H01H73/02—Details
    • H01H73/06—Housings; Casings; Bases; Mountings
    • H01H73/10—Cartridge housings, e.g. screw-in housing

Definitions

  • the present invention relates to an automatic circuit breaker of the type which serves to protect electrical installations and responds to excessive currents and, more particularly, to an overload of the electrical installation and to short-circuits occurring therein. Automatic circuit breakers of this type are frequently used in lieu of fuses.
  • Prior automatic safety circuit breakers of the bimetal-controlled type which did not contain any electromagnetic devices did not comply with that requirement as they were either too slow in responding to a short-circuit or too sensitive to permit the operation of the installation over a limited period of time at an overload of from 1.1 to 2 times the normal current. It lies within the nature of the fiexure characteristic of bi metal elements heated by the current controlled that the objectionable characteristics of the bimetal breaker cannot be improved by a simple adjustment of the bimetal element, because the correction rendering the breaker sensitive to a short-circuit is inconsistent with the correction that would be required to render the breaker slowly responsive to overload currents.
  • Fig. l is an elevation of an automatic circuit breaker in closed condition
  • Fig. 2 is a side view of Fig. 1,
  • Fig. 3 illustrates the bimetal element of the circuit breaker shown in Figs. 1 and 2,
  • Fig. 4 is an elevation of a circuit breaker similar to that of Fig. 1,
  • Fig. 5 is a side view thereof
  • Fig. 6 is an elevation of another circuit breaker embodying the present invention and slightly differing from that shown in Fig. 4,
  • Fig. 7 is a side view of the breaker shown in Fig. 6,
  • Fig. 8 is an axial section of an automatic circuit breaker adapted to be screwed into a fuse socket, the section being taken along the line 88 of Fig. 10 and showing the contacts in closed condition,
  • Fig. 9 is a sectional view of the same circuit breaker, the housing being shown in section taken along the line 9-9 of Fig. 10,
  • Fig. 10 is a cross section taken along the line 10-10 of Figs. 8 and 9,
  • Fig. 11 is a partial sectional view similar to that of Fig. 8 showing the contacts in separated condition
  • Fig. 12 is a sectional view similar-to that of Fig. 17, but showing the contacts in separated condition.
  • Figs. 1 to 3 1 denotes a bimetal element through which the current flows, 2 are movable contacts mounted thereon, 3 denotes stationary contacts carried by. terminal members 4 provided with clamping screws 5.
  • 7 denotes heat-dissipating fins of metal or ceramic material of a high heat conductivity. Such fins may be formed of bimetal as shown.
  • 8 denotes means for opening the con-. tacts, and more particularly springs acting on the bimetal element carrying the contacts.
  • 9 denotes a stationary stop adapted to be engaged by the bimetal element.
  • an automatic circuit safety breaker which is adapted to be screwed into a socket of a fuse as a substitute therefor.
  • the breaker has a plugshaped housing of insulating material which is divided lengthwise into sections 31a and 31b and has external threads adapted to receive a threaded sheet metal ring 44 which holds the sections 31a and 31b together and'which constitutes an Edison thread permitting the housing to be screwed into a fuse socket.
  • the housing is provided with a bore in its top and with a cap 49 of insulating material fitted on the top portion of the housing 7 and provided with a central bore and an internal collar 50 surrounding such bore and extending into the bore provided in the top of the housing.
  • the bottom of the housing is provided with a bore accommodating a flanged metal plug 45 which. .has .a threaded end portion projecting from the housing 31a, 31b and engaging internal threads of .a bottom contact 43.
  • this bottom contact is cylindrical and the lower portion thereof has external threads.
  • a re-setting member of insulating material in :form ,of a bolt provided with a peripheral shoulder 35 between its ends has an upper cylindrical portion 32 slidably guided in the cylindrical bore of the cover 49 and projecting therefrom to form an actuating button, and a reduced lower end 34 slidably guided in an internal. bore of the member .45.
  • the cylindrical portion 33a from which the reduced portion 34 extends downwardly is fitted in a bracket 33 and rests on an internal flange of such bracket. The latter is urged in upward direction by'a helical spring 46 which surrounds the reduced portion34 of the "resetting member and is inserted between the bracket 33 and the member 45. As long as the contacts are closed, the re-setting member is arrested in the position shown in Figs.
  • a flanged sleeve 51 of resilientmaterial surrounds the re-setting member and, more particularly, the collar 32b thereof and has its flange clamped between the housing and its cap.
  • the compressed gaseous medium presses the sleeve 51 againstthe collar 32b to thereby seal the gap between the knob 32 and the cap 49 of the housing.
  • the sleeve 51 preferably consists of a material capable of resisting high temperatures.
  • a sheet metal cap 48 may be inserted between the cap 49 and the housing to assist in holding the housing sections 31a and 31b together against high internal pressure.
  • the external thread of bottom contact 43 is selected in dependence on the nominal current of the automatic safety breaker. Preferably, a diameter of 6 millimeters is employed for 6 amperes, a diameter of 8 millimeters for 10 amperes, a diameter of 10 millimeters for amperes, a diameter of 12 millimeters for amperes, and a diameter of 14 millimeters for amperes.
  • the safety breaker is to be inserted into the socket of an ordinary screw fuse by means of the Edison thread 44, the threads of the bottom contact 43 will just pass through the corresponding holes of the sockets.
  • special sockets may be provided having a threaded hole into which the bottom contact 43 may be screwed.
  • the special socket will not be provided with threads for engagement by the Edison threads 44, but will be provided with an annular contact shoulder adapted to be engaged by the shoulder provided at the bottom of threads 44.
  • the bottom contact may have a standard thread of 6 millimeters diameter, for instance, for all nominal currents and may have a reduced end, the diameter of which is dimensioned to suit the nominal current.
  • the bottom contact 43 may be free from any threads and itsdiameter may be dimensioned in dependence on the nominal current, as is customary with screw fuses.
  • the portions 32, 32a, 33a, 34 and 35 may be formed 4 by individual elements which are rigidly connected with one another by a suitable adhesive.
  • an enlarged chamber is provided in the upper portion of the insulating housing.
  • a pair of stationary contacts 42 is mounted on the ceiling of the enlarged chamber on either side of the sleeve 51 in diametrical opposite relationship.
  • One of these contacts is carried by a conductive strip 41a extending along the ceiling of the chamber outwardly into the wall of the insulating housing being embedded therein and extending downwardly into contact with the bottom contact 43, as will appear from Figs. 8 and 9.
  • the other contact 42 is likewise carried by a conductive strip 41b which extends along the ceiling of the chamber in outward direction and into the wall of the housing being embedded therein and leading downwardly into contact with the threaded sheet metal ring 44.
  • Vertical ribs 52 are provided on the internal wall of the housing for the purpose of extending the creeping current path between the contacts 42.
  • a pair of movable contacts 37 disposed below the pair of contacts 42 is mounted on a bimetal element 36.
  • the bimetal element includes bridge portions 62 and a pair of U-shaped portions 36a and 3612..
  • Each of these portions 36a and 36b is a vertical flat U-shaped plate of bimetal, the arms of which extend upwardly from a base 61 illustrated in Fig. 17 in section.
  • the opposed,upwardly extending arms of the .U-shaped portions are integral with the horizontal bridge portions 62 extending on either side of the re-setting member transversely to the same.
  • Suitable mounting means are provided for guiding the bimetal element 36 for movement towards and away from the pair of'staticnary contacts 42.
  • such mounting means comprises a pair of protective burnoff sheet metal members 38 which are placed on the bridge portion 62 of the bimetal element 36 and are suitably secured thereto, for instance by rivets which serve at the same time to secure the movable contacts 37 in position.
  • Each of the sheet metal members has a pair of projections 39 (Fig. 18) which embraces a square section of portion 32a of the re-setting member and is slidably guided on the edges thereof for vertical movement.
  • each of the U-shaped portions 36a and 35b is provided with a fin of a heat-conductive material which extends from the bimetal portion and will dissipate the heat produced therein into the surrounding atmosphere.
  • Each of the two fins is formed by a U-shaped bimetal strip 40a, or 4311 respectively, which is disposed in upright inverted position and has its outer leg fixed, for instance welded, to the base 61 of the U-shaped portion and has the other leg extending between the base 61 and the re-setting member into contact with the upper shoulder formed by the collar 35 thereof, as shown in Fig. 9.
  • a pair of springs 47 constituting means for opening the contacts tends to pull the contact-carrying bimetal member 36 downwardly relative to the re-setting member but is normally prevented from so doing by engagement of the fins Mia, 40b with the collar 35.
  • Each spring 47 is a helical spring having one end anchored to the bracket 33 secured to the re-setting member and having the other end secured to a lip 63 which is punched out of the sheet metal member 38 and bent downwardly therefrom.
  • the bimetal element 36 consists in a known manner of two layers of metal which are welded to each other and have different coeflicients of heat expansion.
  • the current is conducted from the bottom contact 43 through the conductive strip 41a, the stationary contact 42, the movable contact 37 in engagement therewith, the associated bridge portion 62, the pair of U-shaped portions 36a and 36b, the other movable contact 37, the associated stationary contact 42, and the conductive strip 41b to the threaded sheet metal ring 44, the U-shaped portions 36a and 36b will be heated when the current exceeds its norm and by such heat are subjected to a deformation causing the U-shaped portions to be deflected in the direction of the arrows 36a and 36b in Fig. 17 outwardly.
  • the U-shaped fin portions 40a and 40b likewise consist of bimetal, they will be likewise subjected to heat flexure. However, their limbs are spread apart by said heat flexure. Hence, the heat flexure occurs in the direction indicated by arrows 40a and 40b opposite to the deformation 36a and 36b of the U-shaped portions 36a and 36b. Consequently, the heat flexure of the fin portions 40a and 401: will partly compensate the deformation of the U-shaped portions 36a and 3612.
  • the member 45 and the bottom contact 43 may be made integral with each other.
  • the displacement from normal position of the lower ends of the bimetal element 36 which in the embodiment shown are formed by the inner limbs of the U-shaped fins 40a and 40b, may amount to 0.3 millimeter, for instance.
  • the bimetal latching mechanism formed by the bimetal element 36 and the re-setting member'provided with collar 35 will be unlocked and will release the contacts 37 for separation by the springs 47.
  • the fins 40a and 40b render the safety breaker comparatively insensitive, as far as an overload of the installation is concerned.
  • These fins do in no way affect the responsiveness of the novel automatic circuit breaker to short-circuits.
  • the main U-shaped portions 36a and 36b are so suddenly heated that their deformation .36!) reaches a limit far lower than the temperature limit 6 that causes the breaking of the circuit in response to an overload.
  • the provision of the fins 40a and 40b does not affect the response of the novel circuit breaker to a short-circuit.
  • the button 32 For the purpose of re-setting the breaker to contact closing condition in which the elements assume the posi tions illustrated in Figs. 8 and 9, the button 32 must be depressed causing the collar 35 to descend below the lower ends of the inner limbs of the auxiliary U-shaped bimetal fins 40a and 40b at the same time depressing bracket 33 thereby compressing spring 46 and stretching the springs 47.
  • the spring 16 On subsequent release of the button 32 the spring 16 will lift the re-setting member, and the collar 35 thereof will rise into engagement with the bimetal element 36 resting on the internal housing shoulders 60
  • the collar 35 thereof On further upward movement of the re-setting member, the collar 35 thereof will lift the bimetal element from the shoulders 60 and will return the elements into contact-closing positions shown in Figs. 8 and 9.
  • the bimetal element 36 constitutes in effect a latch which consists of bimetal and in normal condition is operative to lock the contacts in closed relationship.
  • the latch releases the contacts for separation by the springs 47
  • the fins 40a and 40b forming part of the bimetal element 36 are in effect delaying means which are responsive to a slow heat production extending over a period of time exceeding a few seconds and delay the effect of the deformation of the main bimetal portions 36a and 36b, but which do not respond to a quick heat production caused by a short-circuit whereby the novel safety breaker will slowly respond to an overload but will quickly respond to a short-circuit.
  • the breaker is characterized by the provision of the bimetal element with means influencing the deformation of the bimetal element when the same responds slowly over a period of time from one hour to a few seconds, such means being not effective when the response occurs within a brief period in the order of a few seconds or less.
  • the novel safety breaker complies with the requirement that when a short-circuit occurs, the opening of the contacts must be effected within a limited period of time as quickly as possible.
  • the amount of displacement of the latching means resulting in a release thereof from the stop or collar 35 has been reduced to a very short distance and, therefore, the responsiveness to an overload current exceeding the norm by 10 to 20 percent has been artificially delayed by the provision of the delaying means, such as 40a and 40b.
  • the artificial delay of the response to a current exceeding the norm by 10 to 20 percent is partly due to the fact that the heat produced by the current in the main bimetal portions, such as 36a and 36b, is transferred to the fins, such as 40a and 40b, and dissipated thereby into the surrounding atmosphere. Owing to such heat dissipation the main bimetal portions are effectively cooled. As a result, it takes a longer period of time until the novel breaker will respond to the overload current and break the same. When the overload amounts to from 10 to 20 percent of the norm, the contacts will be opened after a period of time which may extend from thirty seconds to thirty minutes.
  • the retarding efiect produced by the fins 46a and 40b is enhanced by'the fact that such fins themselves consist of bimetal and are thus subject to a heat fiexure partly compensating that of the main bimetal portions. That is the reason why in the embodiment shown the fins rather than the main portions 7 of the bimetal elements cooperate with the stop 35.
  • the breaker would respond within about three minutes to an overload current exceeding the norm by 20 percent. The threeminute period, however, is much too short to comply If the fins would consist of ordinary metal as distinguished from bimetal, the dimensions being otherwise the same, the breaker would respond to an overload current exceeding the norm by 20 percent after a period of time in the order of fifteen minutes. Owing to the fact that the fins consist of bimetal, the period of response to an overload current exceeding the norm by 20 percent has been extended to a period in the order of twenty-five minutes, for instance.
  • any desired extension of such period may be attained by suitably dimensioning the fins.4tla and ibb without adversely afiecting the responsiveness of the breaker to a short-circuit.
  • the bimetal element itself constitutes in effect a latch locking the contacts in closed condition and releasing the same for spring-actuation for the purpose of breaking the contacts.
  • a separate latch may be provided in addition to the bimetal element and may be cooperatively connected therewith for engagement and disengagement.
  • the bimetal element conducting the current to be controlled is of U-shapeand cooperates with the resetting member.
  • This arrangement offers particular advantages where the invention is applied to a safety switch of the type adapted to be substituted for a screw. fuse.
  • An automatic circuit breaker of this type offers the advantage that it affords the possibility of closing the contacts by simple manipulation after the cause of the overload or the short-circuit has been eliminated as distinguished from a screw fuse which must be replaced in event of a response to an overload or ashort-circnit.
  • novel automatic circuit breaker consists of simple elements lending themselves to cheap manufacture and assembly as distinguished from prior circuit breakers including electromagnetic devices for the purpose of quickly responding to shortcircuits.
  • the novel automatic safety switch serving to protect electrical installations from excessive overload and from damage by short-circuits is provided with a re-setting button cooperating with the bimetal element, the latter including the described delaying means which delay the response of the safety, switch to an overload but will not delay the response to a short-circuit.
  • the fin 7 of the bimetal element 1 rather than the main portion thereof that cooperates with the stationary stop 9.
  • the fin 7 consists of bimetal.
  • the embodiment illustrated in Figs. 4 and 5 has a shape of the bimetal fin 26.
  • the stationary contacts 23 are mounted on terminal members 24 provided with clamping screws25.
  • the U-shaped bimetal element 21 carries the movable contacts 22 and is guided for up and down motion by suitable means, not shown.
  • the bimetal fin 26 is U-shaped and has one ofits'limbs suitably secured,
  • Automatic circuit breaker responsive to overload and to 'short-circuiting comprising a pair of contacts,'means for opening said contacts, a bimetal element in series with said contacts to be heated by the current under control and adapted to actuate said opening means by heat for movement towards and away from said pair of stationary contacts, said bimetal element including a pair of U-shaped portions, a pair of movable contacts each mountedon said U-shaped portions in position for en- 'gagement and disengagement of said pair of stationary contacts, resilient means mounted to act on said bimetal element and tending to move same into a contact-separating direction,and a stop disposed between said U-shaped portions, said bimetal members being shaped and disposed to normally engage said stop to be locked incontact-closing position contrary to the tendency of said resilient means, but being adapted by heat flexure to disengage said stop and to thereby cause said resilient means to become effective and to move said bimetal element to contact-separating position, said U-shaped portions of said bimetal element constituting

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US513842A 1954-06-08 1955-06-07 Automatic circuit breaker Expired - Lifetime US2875296A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH2875296X 1954-06-08

Publications (1)

Publication Number Publication Date
US2875296A true US2875296A (en) 1959-02-24

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US513842A Expired - Lifetime US2875296A (en) 1954-06-08 1955-06-07 Automatic circuit breaker

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Country Link
US (1) US2875296A (enrdf_load_stackoverflow)
BE (1) BE538489A (enrdf_load_stackoverflow)
CH (3) CH327891A (enrdf_load_stackoverflow)
FR (1) FR1132466A (enrdf_load_stackoverflow)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2980779A (en) * 1958-10-22 1961-04-18 Ranco Inc Motor protector
US3238335A (en) * 1962-06-05 1966-03-01 Robertshaw Controls Co Thermal time delay electric switch means having selectively adjustable on and off times
US3423712A (en) * 1965-05-15 1969-01-21 Gen Electric Canada Thermal protective device having rapid response to sudden high overloads and delayed response to moderate overloads
US20100042652A1 (en) * 1999-02-05 2010-02-18 O'donnell Michael System for tracking distribution for internet-distributed works of authorship
US20120237802A1 (en) * 2011-03-14 2012-09-20 Sangwon Byun Secondary battery
US9941549B2 (en) 2013-01-23 2018-04-10 Samsung Sdi Co., Ltd. Rechargeable battery

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1513260B1 (de) * 1965-03-19 1970-01-29 Licentia Gmbh Thermischer Ausl¦ser

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1832194A (en) * 1929-03-27 1931-11-17 Arthur J Esser Fuse device
GB427506A (en) * 1934-02-12 1935-04-25 Cie Continentale Pour La Fabri Improvements in or relating to automatic circuit breakers
US2005687A (en) * 1933-06-20 1935-06-18 Sachs Joseph Current responsive element and method of manufacture therefor
US2050284A (en) * 1932-03-23 1936-08-11 Westinghouse Electric & Mfg Co Circuit interrupter
GB467203A (en) * 1935-11-29 1937-05-31 John Ashworth Crabtree Improvements in, or relating to, motor-protective and other automatic switches or circuit-breakers
US2094199A (en) * 1934-07-25 1937-09-28 Gen Motors Corp Switch
US2313745A (en) * 1941-06-04 1943-03-16 Westinghouse Electric & Mfg Co Thermal switch for fluorescent lamps
US2568423A (en) * 1950-07-07 1951-09-18 Westinghouse Electric Corp Circuit breaker
US2587162A (en) * 1950-01-05 1952-02-26 Mechanical Products Inc Circuit breaker with ambient temperature and shock compensation
US2625625A (en) * 1950-06-02 1953-01-13 Mechanical Products Inc Free trip circuit breaker
US2639348A (en) * 1950-07-01 1953-05-19 Mechanical Products Inc Circuit breaker with spark sealing casing construction
US2665347A (en) * 1952-05-24 1954-01-05 Mechanical Products Inc Electric circuit breaker
US2697151A (en) * 1951-03-24 1954-12-14 Square D Co Circuit breaker

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1832194A (en) * 1929-03-27 1931-11-17 Arthur J Esser Fuse device
US2050284A (en) * 1932-03-23 1936-08-11 Westinghouse Electric & Mfg Co Circuit interrupter
US2005687A (en) * 1933-06-20 1935-06-18 Sachs Joseph Current responsive element and method of manufacture therefor
GB427506A (en) * 1934-02-12 1935-04-25 Cie Continentale Pour La Fabri Improvements in or relating to automatic circuit breakers
GB427512A (en) * 1934-02-12 1935-04-25 Cie Continentale Pour La Fabri Improvements in or relating to automatic circuit breakers
US2094199A (en) * 1934-07-25 1937-09-28 Gen Motors Corp Switch
GB467203A (en) * 1935-11-29 1937-05-31 John Ashworth Crabtree Improvements in, or relating to, motor-protective and other automatic switches or circuit-breakers
US2313745A (en) * 1941-06-04 1943-03-16 Westinghouse Electric & Mfg Co Thermal switch for fluorescent lamps
US2587162A (en) * 1950-01-05 1952-02-26 Mechanical Products Inc Circuit breaker with ambient temperature and shock compensation
US2625625A (en) * 1950-06-02 1953-01-13 Mechanical Products Inc Free trip circuit breaker
US2639348A (en) * 1950-07-01 1953-05-19 Mechanical Products Inc Circuit breaker with spark sealing casing construction
US2568423A (en) * 1950-07-07 1951-09-18 Westinghouse Electric Corp Circuit breaker
US2697151A (en) * 1951-03-24 1954-12-14 Square D Co Circuit breaker
US2665347A (en) * 1952-05-24 1954-01-05 Mechanical Products Inc Electric circuit breaker

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2980779A (en) * 1958-10-22 1961-04-18 Ranco Inc Motor protector
US3238335A (en) * 1962-06-05 1966-03-01 Robertshaw Controls Co Thermal time delay electric switch means having selectively adjustable on and off times
US3423712A (en) * 1965-05-15 1969-01-21 Gen Electric Canada Thermal protective device having rapid response to sudden high overloads and delayed response to moderate overloads
US20100042652A1 (en) * 1999-02-05 2010-02-18 O'donnell Michael System for tracking distribution for internet-distributed works of authorship
US20120237802A1 (en) * 2011-03-14 2012-09-20 Sangwon Byun Secondary battery
US8753765B2 (en) * 2011-03-14 2014-06-17 Samsung Sdi Co., Ltd. Secondary battery
US9941549B2 (en) 2013-01-23 2018-04-10 Samsung Sdi Co., Ltd. Rechargeable battery

Also Published As

Publication number Publication date
FR1132466A (fr) 1957-03-12
CH333333A (de) 1958-10-15
CH327891A (de) 1958-02-15
CH333075A (de) 1958-09-30
BE538489A (enrdf_load_stackoverflow) 1955-06-15

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