US2822431A - Electric switch - Google Patents

Electric switch Download PDF

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Publication number
US2822431A
US2822431A US280252A US28025252A US2822431A US 2822431 A US2822431 A US 2822431A US 280252 A US280252 A US 280252A US 28025252 A US28025252 A US 28025252A US 2822431 A US2822431 A US 2822431A
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Prior art keywords
conductors
bar
bars
vertical
contact
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US280252A
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English (en)
Inventor
Kruithof Jakob
Nys Louis Jacques Ghislain
Donceel Jules Louis Joseph
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International Standard Electric Corp
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International Standard Electric Corp
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H67/00—Electrically-operated selector switches
    • H01H67/22—Switches without multi-position wipers
    • H01H67/26—Co-ordinate-type selector switches not having relays at cross-points but involving mechanical movement, e.g. cross-bar switch, code-bar switch

Definitions

  • the invention relates to an electric switch, e. g. for use in telephone systems, and more particularly to a switch of the type disclosed in the Belgian Patent No. 488,634 (J. Kruithof 40) which is essentially a multiswitch, i. e. a switch with a plurality of inlets and a plurality of outlets with means for the interconnection of any one inlet with any one outlet.
  • the switch disclosed in that patent included two main parts: the contact bank and the operating mechanisms for establishing a connection between an inlet and an outlet.
  • the contact bank formed a three-dimensional lattice of spaced crossing points between conductors respectively belonging to a first and to a second set. Parallel rows of such crossing points could then be bridged by means of contact fingers and the operation of these contact fingers was controlled by means of a crossbar arrangement, i. e. a set of clutch or select bars and another set of hold or actuating bars permitting to select a particular contact finger by using a number of electro-magnets controlling these bars which is appreciably smaller than the total number of fingers.
  • the object of the invention is to improve the type of switch described above, one particular object being a reduction in the number of select or clutch bars which are necessary for a switch having a predetermined num ber of outlets.
  • a feature of the invention resides in an electric switch with a plurality of inlets and a plurality of outlets and comprising a first set of fixed parallel conductors, i. e. outlet conductors, a second set of parallel conductors substantially perpendicular to those of the first set and interleaved therewith so as to form a three-dimensional lattice of spaced crossing points, parallel rows of which, extending in a direction substantially perpendicular to both sets of conductors, can be bridged by means of outlet contact fingers, one for each row and movable substantially perpendicular to both the first and the second sets of conductors, while furthermore said conductors of the second set are used as intermediate conductors between conductors of the first set, i. e. outlet conductors, and fixed conductors of a third set of conductors, i. e. inlet conductors, whereby each connection between an inlet and an outlet is established via one or more intermediate conductors in series.
  • Fig. 1 a block diagram of a multi-switch
  • Fig. 2 a schematic representation of a multi-switch showing the various contacts
  • Fig. 3 a schematic representation of a modified multiswitch showing the various contacts
  • FIG. 4 a schematic representation of the mechanical parts necessary for the operation of a multi-switch as shown in Fig. 3;
  • FIG. 5 a schematic representation of a partial modification for the switch shown in Fig. 4;
  • FIG. 6 a schematic representation of an embodiment of a multi-switch in accordance with the invention.
  • Fig. 7 a schematic representation of the mechanical parts necessary for the operation of a multi-switch as shown in Fig. 6;
  • FIG. 8 a perspective view of part of the multi-switch schematically shown in Figs. 6 and 7; I
  • FIG. 9 a perspective view of another part of the multiswitch schematically shown in Figs. 6 and 7;
  • FIG. 10 a perspective view of yet another part of the multi-switch schematically shown in Figs. 6 and 7;
  • Fig. 1 shows the general principle of a multi-switch M with m inlets and n outlets.
  • Each of these inlets and outlets may, of course, include any number of conductors, i. e. p, which are used for each connection from any one inlet to any of the outlets.
  • Fig. 2 shows a schematic arrangement for the electrical contacts which are needed for the various connections in the multi-switch M, these contacts being numbered in accordance with the particular connection which the contact can effect, e. g. contact ij provides for the connection of the ith inlet to the jth outlet.
  • contact ij provides for the connection of the ith inlet to the jth outlet.
  • this represents a modification of Fig. 2, in which two-way contacts are used, i. e. contact 11-2 provides for the connection between the first inlet and either the first or the second outlet, in accord ance with the sense of displacement of the contact.
  • the principle of such an arrangement is also well known and has, for example, been disclosed in the Belgian Patent Number 501,688 (G. X. Lens 44).
  • Fig. 4 is a known arrangement representing schematically the necessary mechanical parts for operating the contacts included in the multiswitch M schematically shown in Fig. 3.
  • the Belgian Patent Number 477,334 discloses a contact bank with a plurality of horizontal conductors interleaved with a plurality of vertical conductors so as to form a three-dimensional lattice of spaced crossing points between conductors of the first set and conductors of the second set, i. e. between inlet conductors and outlet conductors.
  • the latter can generally be assumed to be fixed conductors, while the former are resilient or at least portions of these are resilient so as to permit the necessary displacement to establish contact with a corresponding outlet conductor.
  • these horizontal conductors can be provided with suitable contact extensions and therefore only these need be resilient so that they may be displaced to effect contact with an outlet conductor.
  • contact fingers are used to displace the contact extensions provided on the horizontal conductors, in order to establish the connection.
  • These contact fingers as disclosed in said Belgian patent, are located at right angles to both the horizontal and the vertical conductors and they will generally be used to drive a whole row of contacts by displacing the fingers longitudinally in one or the opposite sense. Accordingly, by referring to Fig. 3, these contact fingers, although they are not shown in that figure, can be assumed to be located substantially at right angles to both the inlet and the outlet conductors.
  • Fig. 4 e. g. F will be used to drive a plurality of contacts 11-2, only one of which is shown in Fig. 3 although, in general, there will be a number p of such contacts in accordance with the numberof conductors which are used for each connection between any inletand any outlet.
  • Fig. 4 is more particularly related to-the mechanism necessary for the operation of the fingers .
  • these selective means comprising avertical or select bar corresponding to each vertical row or fingers, e. g. vertical bar V for the fingers suchas F Only the first two (V V and the last (V,, ,,)'ver-tical bars have been shownbut it is evident that thenumber of vertical bars is immaterial anddepends on the capacity of the switch.
  • the selectionof a vertical row of fingers is essentially a clutch operation since the fingers will not be actually displaced. As soon as this selectionis per.- formed, actuating and holding means will be used to cause the displacement of a particular selected finger.
  • This has also been schematically represented in Fig. 4 .by horizontal or hold bars of which only the first two (H H and. the last (H have been shown.
  • Figs. 3 and 4 show in a schematic manner that servo mechanisms are used to cause the displacementof both types of bars.
  • electromagnet such ash/M is first of allused to select-a vertical bar, i. e. V and as soon as thisselection is performed, a common bar H will be displaced under the control of the servo-magnet VS, the latter displacement causing the movement of the selecte vertical bar, i. e. V
  • a servo-magnet can also be used to control the movements of the horizontal bars and al hough each horizontal bar such as H will first of all be selected by the operation of a corresponding electro-magnet, i. e. Hit I the actual operation will heperforrned under the control of the common bars VL and VR which arecontrollcd by the servo-magnets HSL and HSR.
  • the use of two common bars and two servo-magnets is here necessitated in view of the fact that it is desirable to displace the horizontal bars such as H in two opposite senses resulting in the displacement of the corresponding fingers, i e. F also in two opposite senses. This is schematically indicated in Fig.
  • a servo-magnet is particularly advantageous when the horizontal bars are movable in two opposite senses, sinceif this wereavoided, two electro-magnets would have to be used for each horizontal-bar resulting in the use of twice as many electro-magnets such as HM lfthe number of inlets and accordingly the number of horizontal bars is fairly considerable the use of a servomechanism will certainly be advantageous in such a case.
  • Fig. 5 shows a partial modification of the controlling arrangement shown in Fig. 4 andrepresents acode bar mechanism CB,.also called permutation barmechanism, by means of whichthe number ofelectro-magnets such as VM is appreciably reduced, these magnetsbeingreplaced by a smaller number'of so-called code'bar mag:
  • CM a plurality of whichrnay, besimultaneaseaeal ously energized in different combinations, resulting in the selection of a particular vertical bar such as V corresponding to a particular combination.
  • code bar mechanisms generally operate on a binary basis, since electro-magnets are essentially two-condition devices and such a mechanism is for example disclosed in the Belgian Patent Number 493,326 (0. BrackeG. X. Lens 24-46).
  • FIG. 6 shows a schematic representation of the electrical connectionsfor a modified multi-switch M.
  • each inlet conductor is first directed to either one of two intermediate horizontal conductors, thereby affording an additional selection of one out of two.
  • This principle will be exemplified by referring to a connection between inlet No. l and any one of the first four outlets, i. e. Nos. 1-4. Assuming it is desired to establish a connection between inlet No. l andoutlet No.
  • Fig. 7 the'latter schematically shows the mechanical parts for operating a multi-switch as represented in Fig. 6.
  • Fig. 4 only the first horizontal row of contact fingershas been partially represented but it should, of course, be understood that similarhorizontal rows of fing ers are provided for each-inlet.
  • These fingers arelabelled in the same manner as those shown in Fig. 4, in order to show correspondencebetween the fingers and the contacts which they control.
  • finger 'F is the finger controlling'contacts such as 11-2 and 13-4.
  • Two additional fingers per inlet have'also been representcd'in Fig. 7', i. e.
  • the intermediate contact fingers; such asF are also selected in vertical rows by means of vertical select bars such as .Y' -in the same manner. as for the outlet contact fingers; As shown in Fig. 7, a codebar mechanism CB.
  • the advantage of the type of construction disclosed in Figs. 6 and 7 resides in the fact that in this manner the number of vertical bars can be appreciably reduced as compared to the known arrangement shown in Figs. 3 and 4. Assuming that the multi-switch has a capacity of 100 outlets, and that the horizontal bars are movable in two opposite senses, the necessary number of vertical bars will be equal (in the known arrangement) to On the other hand, if intermediate conductors are used, e. g. between contact 1,, and contact 11-2, the number of vertical bars will only be i. e. V V V plus the two vertical bars V and V making a total of 27 vertical bars as compared to the original 100 and showing therefore a reduction of nearly 50%. This has also the advantage of reducing the largest dimension of the switch which is generally determined by the length of the common bar H and accordingly by the number of vertical bars in a row.
  • the increase in size will be determined by the ratio between the number of intermediate contact fingers and the number of outlet contact fingers which, in the example considered, is equal to producing a percentage increase of 8% with respect to the switch of optimum size shown in Fig. 4. Since this is very small it can obviously be disregarded as compared with the advantage of using a substantially reduced number of vertical bars and accordingly a substantially reduced number of contact fingers.
  • FIG. 8 This embodiment is shown in Figs. 8, 9 and 10 which should be assembled as indicated in Fig. 11 and which show a perspective view of a rnulti-switch.
  • the multi-switch is similar to that disclosed in the Belgian Patent Number 488,634 (I. Kruithof 40), in which to each inlet corresponds as indivilual switch, all the various individual switches being piled up on top of one another.
  • an individual switch such as that giving access from inlet No. 1, will therefore comprise the contacts 1a, 1b, 112, 13-4, 156, 17-8, etc. together with the necessary means for operating these contacts, it being understood that the total number of these contacts should, in fact, be multiplied by p, i.: e. the number of conductors necessary for each connection between an inlet and an outlet.
  • the individual switch e. g. that corresponding to inlet No. 8, is mounted on an insulated plate 1006 and essentially comprises a series of ten metal strips 81a, 82a, 83a, 84a, 85a and 81b, 82b, 83b, 84b, 25b, strips 85a, 81b and 82b only being shown.
  • Each of these metal strips, e. g. 85a is provided with a number of oblique contact extensions which are designed to be driven into contact with vertical conductors such as 975 (the 5th conductor of outlet No. 97) or 985 (the 5th conductor of outlet No. 98) (Fig. 9).
  • the metal strips such as 85a correspond with the so-called intermediate conductors which are shown in the latter figure, e. g. the conductor between contact 1a and any of the contacts such as 11-2, 156 etc. for inlet No. 1.
  • the vertical conductors such as 975 and 985 correspond with the fixed outlet conductors which are shown in Fig. 6.
  • All the oblique contact extensions carry contacting strips of precious metal such as 897-985 which, in accordance with the lettering scheme used, refers to the contact permitting the connection of inlet No. 8 to either the fifth conductor of outlet No. 97, or the fifth conductor of outlet No. 98.
  • the horizontal strip 85a terminates into the oblique contact extension which carries the contacts 8a5, which, when driven either in the direction of the arrow f or f' will establish contact between the horizontal strip 85a and the inlet terminal P which is connected to the fifth conductor of inlet No. 8.
  • this corresponds (for the inlet) to contact 1a effecting contact with terminal P to which inlet No. 1 is connected, noting, of course, that the references such as In and P in Fig; 6 cover an arbitrary number of contacts or terminals, e. g. 5, in accordance with the number (p) of conductors necessary for such inlet-tooutlet connection.
  • both the contact extensions carrying respectively, the contacts SM. and 8991001 should be displaced, the first either in the sense of the arrow f or in the sense of the arrow 7%, and the second in the sense of the arrow f so as to establish an electric connection between the vertical conductor 1001 and the inlet terminal P' via the horizontal metal strip 81b.
  • This is, of course, the required operation for one conductor only, i. e. the first and it should also be done simultaneously for the remaining conductors (2nd, 3rd, 4th and 5th) of the inlet-to-outlet connection (not shown).
  • lever 1016 when the lever 1016 has been moved downwards by some operating means which will be de scribed later, it will be engaged in the slot 1011 whereby. upon the horizontal bar H being displaced either in the sense of the arrow f or in the sense of the arrow f the lever 1016 will be driven in that sense and will, therefore, drive the fork-shaped member 1015 which will pivot in a horizontal plane around the pivot 1010', which, incidentally, also carries the spring 1018.
  • each vertical bar V consists of a U-shaped profiled bar which is guided in a fixed plate 1021 (Fig. 10) at its bottom and also through an aperture such as 1022 (for bar V which is not shown) in the fixed part 1023 at its upper end, the top end of the bar VA having, of course, a cross section compatible with the shape of the aperture 1021.
  • Parts ofthe middle side of the U-shaped profiled bar V have been cutaway so as to leave bridge-shaped parts such as 1024-around which resilient strips such as 1025" are fixed, secure fixing'being obtained by the projection 1026, these resilient parts being used to pushthe levers such as 1016 in a downward direction to place them under the control oftheir corresponding horizontal bar.
  • the resilient part 1025 is T-shaped so that the top part of the T, 1027, is used to prevent undue upward displacement of the lever during the displacement of the hor'izontal bar.
  • a centering mechanism has been provided for all the fingers such as P397400 (Fig. 9), this mechanism mainly comprising a spring 1020 which is respectively anchored around the small levers 1030 and 1031. These levers are respectively pivoted at one of their ends in apertures 1031 and 1033 respectively provided in a fixed part 1034. The other ends of these levers, i.
  • the remaining part 1042 of the arm 1040 is located above a set of code bars CB CB CB CB; and CB
  • code bars are the essential part of the code bar mechanism CB schematically represented in Fig. 7 and are each provided with slots in such a manner that when a particular combination of code bars is displaced in the direction of the arrow f slots will be aligned at one particular position along the length of said code bars whereby a lever arm such as 1042 will be able to drop in these slots.
  • any operated finger is maintained in its actuated position by frictional pressure between e. g. the horizontal bar H and the lever 1016.
  • This frictional pressure is quite sufiicient to ensure a safe operation, since pressure is exerted not only by the centering spring 1029 but also by the back pressure on all the ten contact extensions such as 899-1001.
  • the multi-switch can now provide ten conductors for each inlet-to-outlet connection instead of five with, of course, a corresponding diminution in the number of outlets, which becomes fifty instead of one hundred.
  • the two intermediate contact fingers should always be in an actuated position, or else, their corresponding contacts should be by-passed to the inlet conductors.
  • Figs. 8 to 10 shows a code bar mechanism for selecting a particular vertical bar, this is by no means essential and individual electro-magnets could also be used to control each vertical bar. Also, the use of servo-mechanisms such as the horizontal bar H and the vertical bars VL and VR (Fig. 7), are not essential and may be omitted.
  • the invention is neither restricted to a switch of any particular capacity nor to a switch in which only two intermediate vertical bars are used.
  • each finger now controls 4x5 contacts, i. e. 20 contacts instead of 10, and this may become a limiting factor.
  • the real disadvantage will be the increase in the size of the switch as compared to the optimum size and therefore the use of more than two intermediate vertical bars is probably only of advantage (for economic reasons) when the multi-switch has a larger number of outlets.
  • a clutch operating mechanism for an electric multiswitch comprising a plurality of spaced clutch members extending in a first plane, first actuating means for moving said members in a direction perpendicular to said first plane, a plurality of spaced actuating elements extending in a second plane perpendicular to said first plane for moving said clutch members into clutching relation with said first actuating means, second actuating means for moving said elements, a plurality of parallel movable code bars extending in a direction having a third plane, said third plane perpendicular to both said first and said second planes, a plurality of separate latch means, each pivotally connected to a different one of said elements, said latch means having a first portion and a second portion, said first portion extending transversely across said code bars and adapted to engage said bars under control of said second actuating means, said second portion adapted to be engaged by said second actuating means upon movement of said code bars to a predetermined position said first portion adapted to be pivoted against said code bars under control of said
  • each of said elements comprises a member having a plurality of spaced projecting strips extending perpendicularly therefrom, each strip associated with a different one of said clutch members and adapted to remain in movable engagement therewith.
  • An electric cross-bar multi-switch for use in a telecommunications system comprising a first set of spaced parallel conductors (e. g. outlet conductors) arranged in rows in two directions at right angles, a second set of parallel conductors substantially perpendicular to those lit of said first set and interleaved therewith so as to form spaced crossing points,- said second set of conductorscomprising a first plurality of spaced movable" contacts, first means for moving said contacts in either one of two directions substantially perpendicular to said first set of conductors to make electrical contact with either one of two of said first set of conductors according to the direction in which they are moved, a third set'of conductors (e. g.
  • said second set of conductors comprising further movable contacts, additional means for moving said further contacts to make contact with either one of a pair of said third set of conductors, the conductors of each said third pair of conductors being electrically connected together and common actuating means for actuating both said first moving means and said additional moving means, whereby a circuit path from a given conductor of said third set to a given conductor of said first set, includes a given conductor of said second set via a first movable contact and a further movable contact associated therewith.
  • said first moving means comprises a plurality of parallel outlet contact fingers each adapted to move corresponding ones of said first movable contacts associated with conductors of said second set
  • said additional moving means comprising an intermediate contact finger mounted parallel to said plurality of outlet contact'fingers and adapted to move corresponding ones of said further movable contacts associated with conductors of said second set
  • said common actuating means comprising a drive-bar, separate clutch means intermediate each of said contact fingetsand said drive-bar, said drive -bar adapted to move in a selected one of said outlet contactfing'ers and said intermediate contact finger simultaneously in the desired 7 direction, whereby'ea'ch connection between an inlet and 1 an outlet is established through two electrical connections common means for operating said select bars, said operated select bars adapted to couple said clutch mechanisms to said-common drive-bar.
  • A- switch as claimed in claim 9 and wherein said means for selecting a select-bar extending'transverse of said outlet contact fingers comprises a code bar mechamsm.

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US280252A 1951-04-13 1952-04-03 Electric switch Expired - Lifetime US2822431A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL317711X 1951-04-13
NL2787668X 1952-02-12

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US2822431A true US2822431A (en) 1958-02-04

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US280252A Expired - Lifetime US2822431A (en) 1951-04-13 1952-04-03 Electric switch
US329424A Expired - Lifetime US2787668A (en) 1951-04-13 1953-01-02 Assembling arrangement for commutating mechanisms

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US329424A Expired - Lifetime US2787668A (en) 1951-04-13 1953-01-02 Assembling arrangement for commutating mechanisms

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US (2) US2822431A (xx)
BE (2) BE510602A (xx)
CH (1) CH317711A (xx)
DE (1) DE929557C (xx)
FR (2) FR65385E (xx)
GB (1) GB722438A (xx)
NL (1) NL74795C (xx)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3115553A (en) * 1959-05-09 1963-12-24 Automatic Telephone & Elect Automatic telephone systems
US3289127A (en) * 1965-01-19 1966-11-29 Bell Telephone Labor Inc Code-bar controlled coordinated switch

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1339001A (en) * 1917-04-11 1920-05-04 Western Electric Co Cross-bar switch
US1564231A (en) * 1925-12-08 Telephone switch
US2082911A (en) * 1935-11-08 1937-06-08 American Telephone & Telegraph Switch
US2653486A (en) * 1950-01-17 1953-09-29 Int Standard Electric Corp Selecting and controlling mechanism for movable parts
US2664468A (en) * 1949-03-09 1953-12-29 Int Standard Electric Corp Commutating mechanism for crossbar switches

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2239329A (en) * 1937-12-21 1941-04-22 Ericsson Telefon Ab L M Selector

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1564231A (en) * 1925-12-08 Telephone switch
US1339001A (en) * 1917-04-11 1920-05-04 Western Electric Co Cross-bar switch
US2082911A (en) * 1935-11-08 1937-06-08 American Telephone & Telegraph Switch
US2664468A (en) * 1949-03-09 1953-12-29 Int Standard Electric Corp Commutating mechanism for crossbar switches
US2653486A (en) * 1950-01-17 1953-09-29 Int Standard Electric Corp Selecting and controlling mechanism for movable parts

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3115553A (en) * 1959-05-09 1963-12-24 Automatic Telephone & Elect Automatic telephone systems
US3289127A (en) * 1965-01-19 1966-11-29 Bell Telephone Labor Inc Code-bar controlled coordinated switch

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FR1059933A (xx) 1954-03-29
GB722438A (en) 1955-01-26
DE929557C (de) 1955-06-30
BE510602A (xx)
BE516812A (xx)
FR65385E (fr) 1956-02-09
CH317711A (de) 1956-11-30
US2787668A (en) 1957-04-02
NL74795C (xx)

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