US3900807A - Magnetically controlled switching device - Google Patents

Magnetically controlled switching device Download PDF

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Publication number
US3900807A
US3900807A US408816A US40881673A US3900807A US 3900807 A US3900807 A US 3900807A US 408816 A US408816 A US 408816A US 40881673 A US40881673 A US 40881673A US 3900807 A US3900807 A US 3900807A
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United States
Prior art keywords
reed
reed switches
multiple connecting
terminals
coil
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
US408816A
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English (en)
Inventor
Michihiro Hamada
Youji Maeda
Shinichi Inoue
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.)
Fujitsu Ltd
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Fujitsu Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from JP10907472A external-priority patent/JPS5242223B2/ja
Priority claimed from JP12598572U external-priority patent/JPS536324Y2/ja
Priority claimed from JP12598472U external-priority patent/JPS5215142Y2/ja
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Application granted granted Critical
Publication of US3900807A publication Critical patent/US3900807A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • H01H67/30—Co-ordinate-type selector switches with field of co-ordinate coil acting directly upon magnetic leaf spring or reed-type contact member
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00—Electromagnetic relays
    • H01H51/28—Relays having both armature and contacts within a sealed casing outside which the operating coil is located, e.g. contact carried by a magnetic leaf spring or reed
    • H01H51/282—Constructional details not covered by H01H51/281
    • 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
    • H01H67/24—Co-ordinate-type relay switches having an individual electromagnet at each cross-point

Definitions

  • ABSTRACT A magnetically controlled switching device in which a plurality of reed relays are arranged in matrix array, each relay being composed of a plurality of reed switches, and which has the following characteristic features. Firstly, a coil form where the reed switches are positioned provides guides which introduce leads of the reed switches toward the edge portion of the coil form. The end of the leads are bent so as to easily introduced the leads along the guides of the coil form.
  • the reed relays are disposed so that the lead terminals are not arranged in the direction of the multiple connecting wires and the leads and the projected portions are respectively connected.
  • the coil forms where said reed switches are positioned and a group of terminals for the exciting coils are fixed to a magnetic shunt plate. Said magnetic shunt plate, said coil forms. said group of terminals, terminal flanges which insulate said terminals and supporting members which support the base plate on which the multiple connecting wires are arranged are formed simultaneously as one body with synthetic resin.
  • the present invention relates to a magnetically controlled switching device, which is composed of reed switches and is principally used for speech path switches and for electronic switching system.
  • reed switches are used as crosspoint switches of speech path circuits in electronic switching systems.
  • reed relays are arranged in matrix form and a speech path circuit is selected by exciting reed relays which are positioned at the crosspoints.
  • the magnetically controlled switching device using reed switches which have a function of selecting such speech path circuit is widely used.
  • the construction of such magnetically controlled switching device is disclosed, for example, in THE BELL SYSTEM TECHNICAL JOURNAL, VOL. 43, PART I, January, I964, pp 25-30 (FIGS. 7-H) and the corresponding explanation).
  • magnetically controlled switching devices are divided into two types, that is, electrically holding type and magnetically latching type.
  • electrically holding type In the magnetically latching type, there is no current and no electrical loss during the hold condition and, consequently. many advantages can be expected from this type.
  • the present invention relates to a magnetically latching type magnetically controlled switching device.
  • a conventional type of magnetically controlled switching device requires a magnetic core plate for latching composed of semihard magnetic material, at every crosspoint because the reed switch used in said device has no holding function of its own.
  • the type FDR 8 reed switch which has now been developed by Fujitsu Limited. utilizes semi-hard magnetic material in the reed member of said reed switch and has a magnetic latching function due to the residual magnetism of the reed members.
  • said FDR-8 reed switch is an epoch making switch due to the fact that the magnetic core plate for latching which is conventionally required can be removed, and the magnetic in tcrference between crosspoints is small because the residual magnetism of the reed members can be directly utilized to close the contacts,
  • the magnetic latching type magnetically controlled switching device F-IL which utilizes this type FDR-8 reed switch and which was developed by Fujitsu Limited, has a simpler and smaller construction and stabler action than the conventional speech path switch which requires a magnetic core plate for latching at every crosspoint. Further, the magnetic latching type magnetically controlled switching device F- I L is considerably smaller and lighter than the conventional speech path switch. Further because the number of its components is less its construction is simple. Consequently. the F-IL device is increasingly used as the speech path switch in electronic switching systems.
  • miniaturized reed switch When such miniaturized reed switch is used in a coil form the distances between the lead terminals are so small that connection of the multiple connecting wires to the lead terminals is difficult and short circuit between said lead terminals are easily caused. Further, when a large scale electronic switching system is assembled by using such miniaturized reed switches, a large number of components and a great amount of labor are required. Consequently, low cost due to mass production cannot be expected.
  • the object of the present invention is to provide a magnetically controlled switching device which overcomes the above-mentioned problems.
  • the magnetically controlled switching device has a plurality of reed switches having a magnetically latching function, and a plurality of coil forms containing said reed switches and around which the driving coils of said reed switches are wound, and which connects the lead terminals of the reed switches with the vertical and horizontal multiple connecting wires, and the device provides: (a) holding portions for holding said lead terminals in edge portions of the coil forms, and; (b) holes for obliquely passing through the lead terminals in said holding portions so that the lead terminals which are bent are easily passed through said holes.
  • the horizontal and vertical multiple connecting wires to which the above-mentioned lead terminals are connected provide projections having a U-shaped bent part in every matrix crosspoint.
  • a line drawn between adjacent lead terminals in a coil form is at an angle to the direction of the multiple connecting wires, and the connections between the lead terminals and the multiple connecting wires are effected in the above-mentioned U-shaped bent part.
  • the magnetically controlled switching device provides, on a magnetic shunt plate, coil forms and insulating plates which provide a plurality of terminals for driving wires of the reed switches, and supports the magnetic shunt plate with supporters, said coil forms, said insulating plates and said supporters for supporting said magnetic shunt plate are formed simultaneously as one body by molding with synthetic resin.
  • FIG. I is a general view of a four wire magnetically controlled switching device
  • FIG. 2 is a partially enlarged view of the device shown in FIG. 1;
  • FIGS. 3A and 3B are diagrams explaining the connection of the multiple connecting wires shown in FIG.
  • FIG. 4 is a further partially enlarged view of the device shown in FIGS. 1 and 2;
  • FIG. 5 is a crosspoint used in the present invention.
  • FIGS. 6A and 6B are diagrams explaining a function of reed switch shown in FIG. 5;
  • FIGS. 7A and 7B are diagrams showing the construction of the conventional coil form for a reed switch
  • FIGS. 8A and 8B are diagrams showing the construction of the coil form for the reed switch according to one embodiment of the present invention.
  • FIG. 9 is an enlarged view of the holding part of the coil form shown in FIG. 8;
  • FIG. is a diagram explaining the construction of the magnetic shunt plate of the magnetically controlled switching device of one embodiment of the present invention.
  • FIG. 11 is a section of an enlarged portion of the coil form and the control terminal shown in FIG. 10.
  • a coil form 1 contains a plurality of reed switches which are used as crosspoint switches, as mentioned hereinafter, and outside of each 1, a driving coil 8 which drives the above-mentioned reed switch 1 is wound.
  • a magnetic shunt plate 2 is composed of magnetic material and provides a plurality of holes for arranging the above-mentioned coil forms 1 in matrix array.
  • Horizontal and vertical multiple connecting wires 3 and 9 shown in FIG. 2 connect the lead terminals 6 of the reed switches held in the coil forms 1 with the output terminals (hereinafter described) of the circuits of the speech path.
  • Said multiple connecting wires 3 and 9 are composed of high permeability magnetic material and are capable of relieving and demagnetizing effect between reed switches. Such phenomenon is frequently produced when the reed switch is miniaturized.
  • FIG. 3A shows a case where exciting coils XX and YY' (hereinafter described) corresponding to the reed switches positioned at special crosspoints are selectively excited and the other reed switches positioned in the same rows and columns are restored.
  • a surface determined by the one dot chain lines x, and y; represents the magnetic shunt plate surface, and the length of the arrows and the arrow heads, shown along the one point chain lines, respectively represent the magnitude and the direction of the magnetic field applied to the reed member of each reed switch.
  • a surface determined by the two dot chain lines x, y represents multiple connecting wires 3 and 9.
  • the reed member of the reed switch which is positioned at the crosspoint (x y,-), multiple connecting wires 3, 9, the reed members of the reed switches which are positioned in the identical row or column adjacent to said reed switch and the magnetic shunt plate constitute a closed magnetic path. Therefore, when the excitation as shown in FIG. 3A is carried out, the reed member positioned at the crosspoint receives the additional magnetic flux from the adjacent reed switches. Then, even if the required magnetomotive force is small, the function of the reed member can be effected.
  • FIGS. 2 and 4 As shown in FIG. 2, four reed switches are inserted in the respective coil forms 1 so as not to lie on the same line with respect to the longitudinal directions of the respective multiple connecting wires 3 and 9, and connected to said respective multiple connecting wires 3 and 9.
  • the multiple connecting wires 3 and 9 are respectively arranged on the same plane in parallel, with a substantially equal distance between adjacent connecting lines.
  • FIG. 4 is an enlarged perspective view illustrating a method of connecting the vertical multiple connecting wires 3 and the upper lead ends 6 of the four reed switches inserted in the coil form 1 and arranged at the four corners thereof.
  • the horizontal multiple connecting wires 9 and the lead ends 6 are connected in the same manner as the wires 3 and the lead ends 6.
  • a projection 7, for engagement with each reed end 6, is formed on each multiple connecting wire 3 at the connecting portion of 3 and 6.
  • This projection 7 is composed of a U-shaped bent portion 11 the inside of which contacts the lead end 6, and a supporting portion 10 supporting the bent portion 11 so as to prevent the bent portion from contacting the adjacent multiple connecting wire 3.
  • the multiple connecting wires 3 and the reed switches contained in the respective coil forms I are arranged in the same manner as explained in FIG. 2, and the bent portion 11 of the projection 7 is engaged with and then soldered to the lead end 6. As a result of this arrangement the work of the assembly becomes very easy.
  • FIG. 5 shows the relation between the coil form I and the reed switches 13-15 which are contained in the bobbin 1.
  • four remanent reed switches I3, 14, 15 and 16 are contained in the wire coil form 1, and the lead ends 6 of these reed switches are arranged in row and column direction as shown in FIG. 2 and FIG. 4 as mentioned above, and connected with the multiple connection wires.
  • FIG. 6A shows the function of the exciting coil, 6 represents one lead end of a reed switch and 2 represents the magnetic shunt plate.
  • the exciting coils XX and YY are wound in opposite direction to each other, and the number of turns of the exciting coils XX and YY' under the magnetic shunt plate 2 are repsectively n, and n (rt n On the other hand, number of turns of the exciting coils XX and YY' above the magnetic shunt plate 2 are respectively n and n (n n And the portion of each exciting coil XX and YY' above the magnetic shunt plate is wound in a direction opposite to that which is wound on the lower side of the magnetic shunt plate. Accordingly, when the exciting current i is applied only to the exciting coil YY', the magnetic field Y shown in FIG.
  • FIG. 7A is a reed switch
  • FIG. 7B is a perspective view partly in broken section, showing a construction of the conventional coil form. Reference numerals which are the same in FIGS. 7A or 7B and in FIG. 5, represent the same meanings.
  • a plurality of remanent reed switches 13 are contained in the coil form I which is inserted in the each hole of the magnetic shunt plate 2.
  • the insertion of the reed switches 13 etc. into the coil form 1, is carried out as follows. Firstly, the lower side leads of said reed switches 13 etc. are held by respective jigs (not shown) and the upper side leads thereof are connected to respective horizontal multiple connecting wires.
  • the construction of the bobbin for the reed switches according to the conventional art has several drawbacks in that the space between the two lead ends of the reed switch becomes small due to the miniaturization of the selector switch, so that it is very difficult to carry out the connecting operation between lead ends of the selector switches and the vertical and horizontal multiple connecting wires respectively, and there is a possibility of producing a dangerous short-circuit phenomenon. Moreover, a large amount of time and a human labor are required for the insertion of the selector switches into the bobbin. Further, it is very difficult to insert the reed switches in so that they are correctly disposed.
  • FIGS. 8A and 8B are perspective views, partly in broken section, of a reed switch and a construction of a coil form according to the present invention.
  • FIG. 9 is an enlarged perspective view, partly in broken section, of a holding member of the coil form shown in FIG. 8B.
  • both lead ends of the reed switches I3, etc. are bent at point 17.
  • a holding member 19 provided with a plurality of guide holes 18 for guiding said bent lead ends of the reed switches 13, etc., are disposed at the upper and lower end portions of a coil form as shown in FIG. 9.
  • a plurality of guide projections 20 for guiding all the reed switches I3, etc., are provided on the inside wall of the coil form I as shown in FIG. 8B.
  • the reed switches 13, etc. are inserted into the coil form I and the bent lead ends of the reed switches 13, etc., are inserted into the guide holes I8.
  • FIG. shows the magnetic shunt plate 2
  • FIG. II shows the portion where the coil form I and control terminals 21 are fixed on the magnetic shunt plate 2.
  • a magnetic shunt plate made of a magnetic material and provided with a plurality of through holes for securely holding therein the coil form 1 control (or junction, repeating) terminals 21 and supporting poles or pillars 22.
  • L-shaped fixtures 23 are mounted on the extended four corners of the magnetic shunt plate 2. These fixtures 23 are used for attaching and earthing the entire device.
  • the magnetic shunt plate 2 is provided with (a) the coil form 1, each containing the reed switches; (b) end flanges 24 for insulating and securing the control terminals 21 connected to corresponding exciting coils, each exciting the reed switches contained in the each coil form 1; (c) the supporting pillars 22 for supporting insulated substrates 25 and 25a, multiple connecting wires 3 connected to the corresponding lead ends 6 of the reed switches disposed above the insulated substrate, and; (d) insulating members 27 for preventing a short-circuit phenomenon between signal terminals 26 and the side surface of the magnetic short-circuit plate 2.
  • the magnetic shunt plate 2, the coil form 1, the end flanges 24, the insulating member 27 and the supporting pillars 22 are formed simultaneously as one body by molding with synthetic resin. As shown in FIG. 11, after heating the control terminal 21, the heated control terminal 21 is pressed into the end flange 24 secured through the through hole formed in the magnetic shunt plate 2.
  • the end portion of the winding wire is firstly wound about the control terminal 21, and after completion of the winding operation a so]- dering treatment is carried out.
  • a so]- dering treatment is carried out.
  • the end portion of the winding wire can be wound about the control terminal 21 by horizontally displacing and turning the winding bit after the winding wire has been wound around the coil form 1. This is a necessary condition for automating the winding operation.
  • the end flange 24 In the case of the conventional art where the control terminal 21 and the end flange 24 are separately formed and then are assembled together, it is necessary that the end flange 24 should have a sufficient thickness from the point of view of the strength and handling thereof. However, in the case of the present device, where the end flange 24 made of a resinous material is firstly formed to the magnetic shunt plate 2 and then the control terminal 21 is pressed into the end flange 24, the thickness of the end flange 24 can be reduced.
  • the construction of the magnetically controlled switching apparatus according to the present invention results in the following three characteristic features.
  • the directions and positions of the respective reed switches can be correctly set by only inserting the lead ends of the reed switches into the guide holes. Further. the connection treatment between the two lead ends of the reed switches contained in the coil form and the multiple connecting wires can be carried out very simply because the space between the lead ends of the reed switches can be increased to approximately twice the length of that of the conventional art.
  • the reed switches contained in the respective coil forms and the vertical and horizontal connecting wires in the manner as shown in FIGS. 2 and 4 the above-mentioned reed switches and multiple connecting wires can be connected on the same plane. Further, the distance between facing connecting portions becomes large, so that operations such as assembling and soldering become very easy. Moreover, even though the distance between two lead ends is reduced due to the miniaturization of the reed switches, the connecting portions can be upwardly projected by providin g the projections on the multiple connecting wires, and the possibility of producing a dangerous shortcircuit phenomenon between the adjacent multiple connecting wires can be extremely reduced.
  • the composition of the magnetic shunt plate can be remarkably simplified. Further, since the magnetic shunt plate acts as an attaching member concurrently with an earth treatment member, the number of circuit components can be decreased. Moreover, the winding operation becomes very easy. Thus the present device displays a great many enhanced effects.
  • a magnetically controlled switching assembly comprising:
  • a magnetically controlled switching assembly according to claim 1, further comprising a magnetic shunt plate on which said coil forms are mounted, a plurality of insulating plates on which are mounted a plurality of terminals for said driving coils, and supporting pillars which support said magnetic shunt plate, said coil forms, said insulating plates, said supporting pillars and said magnetic shunt plate constituting an integral structUI'C.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Switches That Are Operated By Magnetic Or Electric Fields (AREA)
US408816A 1972-10-30 1973-10-23 Magnetically controlled switching device Expired - Lifetime US3900807A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP10907472A JPS5242223B2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1972-10-30 1972-10-30
JP12598572U JPS536324Y2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1972-10-31 1972-10-31
JP12598472U JPS5215142Y2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1972-10-31 1972-10-31

Publications (1)

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US3900807A true US3900807A (en) 1975-08-19

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US408816A Expired - Lifetime US3900807A (en) 1972-10-30 1973-10-23 Magnetically controlled switching device

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US (1) US3900807A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
CA (1) CA994022A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
FR (1) FR2204871B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
IT (1) IT996902B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
NL (1) NL162240C (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
SE (1) SE397432B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3982216A (en) * 1974-09-09 1976-09-21 Nippon Electric Company, Ltd. Electromagnetic coordinate switching device
US4075433A (en) * 1975-10-14 1978-02-21 Nippon Electric Co., Ltd. Signal switching device
WO2006064292A1 (en) * 2004-12-18 2006-06-22 Pickering Interfaces Limited Reed switch arrays

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3431520A (en) * 1966-12-29 1969-03-04 Bell Telephone Labor Inc Reed switches fused by their walls to each other and a metal support member
US3760311A (en) * 1972-04-17 1973-09-18 Datron Systems Inc Reed relay
US3805378A (en) * 1972-02-22 1974-04-23 Bell Telephone Labor Inc Manufacture of remanent reed switch

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1065852A (en) * 1964-01-07 1967-04-19 Ass Elect Ind Improvements relating to the interconnection of electric components
DE1537798C3 (de) * 1966-12-09 1975-08-14 Nippon Electric Co. Ltd. Koordinatenschalter
DE1972052U (de) * 1967-03-01 1967-11-09 Standard Elektrik Lorenz Ag Relaisstreifen mit schutzrohrankerkontakten, vorzugsweise fuer koordinatenmaessig aufgebaute durchschaltenetzwerke.

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3431520A (en) * 1966-12-29 1969-03-04 Bell Telephone Labor Inc Reed switches fused by their walls to each other and a metal support member
US3805378A (en) * 1972-02-22 1974-04-23 Bell Telephone Labor Inc Manufacture of remanent reed switch
US3760311A (en) * 1972-04-17 1973-09-18 Datron Systems Inc Reed relay

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3982216A (en) * 1974-09-09 1976-09-21 Nippon Electric Company, Ltd. Electromagnetic coordinate switching device
US4075433A (en) * 1975-10-14 1978-02-21 Nippon Electric Co., Ltd. Signal switching device
WO2006064292A1 (en) * 2004-12-18 2006-06-22 Pickering Interfaces Limited Reed switch arrays
US20090231774A1 (en) * 2004-12-18 2009-09-17 David Paul Owen Reed Switch Arrays
US8027140B2 (en) 2004-12-18 2011-09-27 Pickering Interfaces Limited Reed switch arrays

Also Published As

Publication number Publication date
DE2354393A1 (de) 1974-05-09
FR2204871B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1978-07-07
NL162240B (nl) 1979-11-15
NL162240C (nl) 1980-04-15
DE2354393B2 (de) 1975-06-19
CA994022A (en) 1976-07-27
NL7314743A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1974-05-02
SE397432B (sv) 1977-10-31
IT996902B (it) 1975-12-10
FR2204871A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1974-05-24

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