US3362013A - Sequential switching device - Google Patents

Sequential switching device Download PDF

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Publication number
US3362013A
US3362013A US360894A US36089464A US3362013A US 3362013 A US3362013 A US 3362013A US 360894 A US360894 A US 360894A US 36089464 A US36089464 A US 36089464A US 3362013 A US3362013 A US 3362013A
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United States
Prior art keywords
reed
switches
switch
line
output
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Expired - Lifetime
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US360894A
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English (en)
Inventor
Abramson Paul
Richard W Bennett
Jr George R Stilwell
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International Business Machines Corp
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International Business Machines Corp
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Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Priority to US360894A priority Critical patent/US3362013A/en
Priority to GB12006/65A priority patent/GB1073054A/en
Priority to DE19651437699 priority patent/DE1437699B2/de
Priority to SE04882/65A priority patent/SE325945B/xx
Priority to CH547865A priority patent/CH429839A/de
Priority to BE662578D priority patent/BE662578A/xx
Priority to FR13770A priority patent/FR1430741A/fr
Priority to NL656504951A priority patent/NL148735B/xx
Application granted granted Critical
Publication of US3362013A publication Critical patent/US3362013A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G08—SIGNALLING
    • G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
    • G08C15/00—Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path
    • G08C15/06—Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path successively, i.e. using time division
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H36/00—Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding
    • H01H36/0006—Permanent magnet actuating reed switches
    • H01H36/0053—Permanent magnet actuating reed switches periodically operated
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H67/00—Electrically-operated selector switches
    • H01H67/02—Multi-position wiper switches
    • H01H67/04—Multi-position wiper switches having wipers movable only in one direction for purpose of selection
    • H01H67/06—Rotary switches, i.e. having angularly movable wipers

Definitions

  • the commutator cannot be used in an explosive atmosphere because the sparks generated by arcing as the terminals make and break and from friction as the terminals rub against each other could be potentially dangerous.
  • the impossibility of preventing ordinary dirt from accumulaitng on the terminals even in a non-contaminated atmosphere prevents such a commutator from being used effectively in a dry circuit (i.e., in a circuit having very low voltage and current requirements). In such a circuit, even the slightest dirt on the terminals could prevent the low power signal from setting through.
  • a commutator using these switches is generally constructed by mounting a magnet on the end of a rotating arm and causing the arm to pass in succession over a group of reed switches. With such a commutator, it is desired that a reed be closed only when the magnet is directly over it.
  • the magnetic lines of force generated by the 3,362,013 Patented Jan. 2, 1968 magnet are not confined in a thin band, but in fact radiate over a small area, so that it is possible that a sufficient number of lines of force will link the next reed to be energized to cause this reed to close while the magnet is still over the preceding reed or, in the more likely situation, that sufficient lines of force will link the last reed energized to maintain this reed closed after the magnet has passed on to the next reed.
  • the non-precision nature of the reeds further complicates this problem.
  • a primary object of this invention is to sample a plurality of switches using a frictionless reed relay commutator.
  • a more specific object of this invention is to obtain precision sampling of a plurality of remote switches using non-precision elements.
  • Another object of this invention is to sample a plu rality of remote switches with a commutator in an explosive atmosphere.
  • this invention provides a sequential switching device, such as a commutator, which is made up of a plurality of switching elements and a means, for example a rotating arm, for sequentially energizing these switching elements.
  • a sequential switching device such as a commutator
  • a means for example a rotating arm, for sequentially energizing these switching elements.
  • the novel feature of this invention which allows non-precision switching elements to be used is a means which is operable during the time period that a given switching element is being energized for deactivating the adjacent switching elements, regardless of whether these elements are open or closed at that time.
  • this means comes into play at the input to the switching elements and is operative during the time period that a given switching element is to be energized to prevent input signals from being applied to the switching elements which are adjacent to the energized switching element.
  • the means for preventing an output from a switching element during undesired periods takes the form of a gate in the output circuit of the switching element, which gate is energized only during time periods when an output signal is desired from the element. Therefore, even if the switching element does generate an output signal during undesired periods, this signal is blocked by the gate. Since in either of the embodiments described above the signals applied to the switching elements are effectively divided into two or more groups, the number of switching elements required in the commutator is increased.
  • FIG. 1 is a schematic diagram of one embodiment of the invention.
  • FIG. 2 is a schematic diagram of a second embodiment of the invention. 1
  • FIG. 3A is a timing chart illustrating the minimum and maximum reed closure times permissible with prior art reed commutators.
  • FIG. 3B is a timing chart illustrating the minimum and maximum reed closure times for the embodiments of the invention shown in FIGS. 1 and 2.
  • FIG. 1 General circuit description, FIG. 1
  • FIG. 1 shows one embodiment of the precision commutator of this invention being used to multiplex informationas to the location of a plurality of switches which may be positioned at one or more remote stations and to detect the open or closed condition of these switches.
  • an arm having a magnet 12 mounted on the end thereof is rotated in a counter-clockwise direction around a hub 14 past a plurality of coils 21-26.
  • a dipulse having a generally sine wave shape is induced in the coil.
  • a second arm 30 having a magnet 32 mounted on the end thereof is rotated in a counter-clockwise direction around a hub 34 past a plurality of reed switches 41-48.
  • Reed switches 41-48 are hermetically sealed and are normally open.
  • a reed switch is closed by placing it in a magnetic field of sufiicient energy.
  • Magnet 32 is of suflicient strength so that a reed switch is closed when the magnet is adjacent to it.
  • Rotating arms 10 and 30 are connected to rotating drive shaft 50 through gear box 52.
  • the gear ratios in gear box 52 are such that arm 11 is rotating at four times the speed of arm 30. Therefore, for each complete revolution of arm 10, arm 30 moves past two reed switches 41-48.
  • each coil 21-26 is connected to common line 54.
  • One terminal of each reed switch 41-48 is connected through a line 61-68 respectively to an input of OR circuit 70.
  • Output line 72 from OR circuit 70 is the information output from the circuit.
  • Output line 81 from coil 21 is connected through diodes 91A-91D to one terminal of switches 101A-101D respectively.
  • Output line 82 from coil 22 is connected through diodes 92A-92D to one terminal of switches 102A-102D respectively.
  • output line 83 from coil 23 is connected through diodes 93A-93D to one terminal of switches 103A-103D respectively.
  • Switches 101A-103A may, for example, be located at one remote station, switches 101B-103B at a second remote station, and so on. The other terminal of each switch 101A-103A is connected through line 111 to the other terminal of reed switch 41.
  • each switch NIB-103B is connected through line 113 to the other terminal of reed switch 43.
  • the other terminal of each switch 101C-103C is connected through line 115 to the other terminal of reed switch 45 and the other terminal of eachswitch 101D-103D is connected through line 117 to the other terminal of reed switch 47.
  • Output line 84 from coil 24 is connected through diodes 122 and 124 and lines 112 and 116 respectively to the other terminal of reed switches 42 and 46.
  • Output line 85 from coil 25 is connected through diodes 126 and 128 and lines 114 and 116 respectively to the other terminal of reed switches 44 and 46.
  • output line 86 from coil 26 is connected through diode 130 and line 118 to the other terminal of reed switch 48. All of the diodes shown in FIG. 1 are connected so that only the positive half of the dipulse generated in coils 21-26 is allowed to pass.
  • the signals generated in coils 21-23 are applied to sample successive contacts 101-103 at remote stations A-D.
  • the particular remote station which is being sampled at any given time is determined by the position of arm 30 over reed switches 41-48.
  • the outputs from coils 24-26 are used to provide a binary code representation of the particular one of the remote stations being sampled at any given time with the signal from coil 24 being the lowest order digit of this number.
  • the outputs are therefore applied to output line 72 in groups of six possible pulses, the first three of which indicate the closed condition of the switches being sampled, and the last three of which indicate the remote station at which the switches are being sampled.
  • FIGS. 3A and 3B show the sets of six possible pulses which may appear on line 72 when any remote station is sampled.
  • the minimum and maximum reed closure times are decreased and increased respectively (reference to FIG. 3B).
  • the minimum and maximum reed closure times shown in FIG. 3B allow rather wide tolerances for the reed which are easy to meet and make a device such as that shown in FIG. 1 both possible and practical.
  • Magnet 12 proceeds past coils 25 and 26.
  • magnet 32 has advanced to a position adjacent to reed 43. It remains substantially adjacent to this reed as magnet 12 passes coils 21, 22 and 23.
  • contacts NIB-103B are sampled in a manner similar to that previously described. It is quite possible that reed 42 will be closed during the early part of this sampling and that reed 44 may close while magnet 12 is still adjacent to 'coil 23; however, since no signals are applied to either reed 42 or 44 during the period that switches 101B-103B are being sampled, no erroneous indication is received.
  • the circuit proceeds to sample the remaining switches in the circuit of FIG. 1 and to apply the binary location code for each of these switches to output line 72 in a manner similar to that previously described.
  • FIG. 2 Alternate embodiment, FIG. 2
  • FIG. 2 The embodiment of the invention shown in FIG. 2 is quite similar to that shown in FIG. 1 and like elements have been given the same number in both figures to assist in correlating them.
  • One difference between the two figures is that there are now six contacts 101-106 being sampled at each of the remote stations, and the pulses in all six of the coils 21-26 are being used for sampling purposes.
  • a second difference is that all the switches at a given remote station are connected through a single line to one terminal of two reed switches. Therefore, line 111v is connected to one terminal of reed switches 41 and 42, line 113 to one terminal of reed switches 43 and 44, line 115 to one terminal of reed switches 45 and 46, and line 117 to one terminal of reed switches 47 and 48.
  • Lines 61, 63, 65, and 67 from the other terminal of reed switches 41, 43, 45, and 47 respectively are commoned and connected as one input to an AND gate 134.
  • Output lines 62, 64, 66, and 68 from the other terminal of reed switches 42, 44, 46, and 48 respectively are commoned and connected as one input to AND gate 136.
  • Output lines 81, 82, and 83 from coils 21, 22, and 23 respectively are connected through diodes 141, 142, and 143 respectively and line 150 as the other input to AND gate 134.
  • Output lines 84, 85, and 86 from coils 24, 25, and 26 respectively are connected through diodes 144, 145, and 146 respectively and line 152 to the other input of AND gate 136.
  • Output lines 154 and 156 from AND gates 134 and 136 respectively are connected as the two inputs to OR gate 158.
  • Output line 160 from OR gate 158 is the circuit output line.
  • magnet 12 is initially positioned adjacent to coil 21' and magnet 32 is initially positioned adjacent to reed 41.
  • pulses are applied through lines 81, 82, and 83 respectively to sample switches 101A, 102A, and 103A respectively. If the first of these switches is closed, a signal is applied through line 111 to one terminal of reed switches 41 and 42. Since magnet 32 is adjacent to reed switch 41 at this time, the vpulses pass through reed switch 41, and line 61 to one input of AND gate 134.
  • the signals applied to lines 81-83 are also applied through a corresponding diode 141-143 and line 150 to the other input of AND gate 134.
  • the signal applied to line 61 is therefore passed through AND gate 134, line 154, and OR gate 158 to output line 160.
  • the resulting signal on line 111 would therefore find both reeds 41 and 42 closed, resulting in the signal being applied to both lines 61 and 62.
  • the signal on line 61 would be passed to output line 160 in a manner previously described.
  • a signal on line 62 is applied to one input of AND gate 136. Since the signal on line 83 is not one of the conditioning inputs to AND gate 136, the spurious signal on line 62 is ineffective to cause an output from the circuit.
  • the energizing of the reed switches 41-48 in the commutator by magnet 32 determines the sequence in which switches at the remote stations are sampled.
  • the time period during which an output is derived from a given reed is determined not by the reed energizing circuit but by the reed activating circuit which includes the pulse generator coils 21-26, the sampled switches, the diodes, and lines 111-118 in FIG. 1 and these elements plus diodes 141-146 and AND gates 134 and 136 in FIG. 2.
  • the reed activating circuit prevents spurious outputs from being derived from a reed during these incorrect time periods.
  • the main advantage of using the technique shown in FIG. 1 is that it reduces the number of logical components which must be employed at the central station.
  • the advantage of using the embodiment of the invention shown in FIG. 2 is that it reduces the number of wires which are run between the central station and the various remote stations. The technique employed will depend on these and other considerations.
  • FIGS. 1 and 2 show the commutators of this invention being used as part of a switch sampling mechanism, and this is one preferred use of such commutators, it is by no means the only way in which these commutators may be used.
  • the teachings of this invention may be employed in any situation where it is desired to obtain a precision commutator while obtaining the benefits inherent in non-precision elements such as reed switches.
  • reed switches have been shown in the preferred embodiments of the invention, and these switches are energized by rotating a magnet past them, the invention may be practiced with any suitable switching device which is sequentially energized in any suitable fashion.
  • FIGS. 1 and 2 show the commutators of this invention being used as part of a switch sampling mechanism, and this is one preferred use of such commutators, it is by no means the only way in which these commutators may be used.
  • the teachings of this invention may be employed in any situation where it is desired to obtain a precision commutator while obtaining the benefits
  • each set of pulses has been divided into two groups, the circuits may be easily modified by providing additional reeds to divide each set of pulses into as many groups as is required to achieve the desired tolerances.
  • the number of pulse generating coils and reeds in the embodiments of FIGS. 1 and !2 has been arbitrarily selected for the purpose of illustrating the invention, and it is to be understood that the number of coils and reeds employed in any application of the invention would depend on the particular design problem presented.
  • a switching device comprising:
  • a commutator having mounted thereon a plurality of switching elements, said switching elements being divided into N groups, each switching element being in the same group as the switching element N positions advanced from it;
  • commutator energizing means for sequentially energizing said switching elements and said signal generating means, said energizing means energizing one of said groups of signal generating means during the time period in which one of said switching elements is energized, N groups of said signal generating means being energized during the time period in which reed switches, each having an input and an output, divided into two groups with alternate reed switches being in each group;
  • a switching device comprising: said sampling lines and a reed switch in said second a commutator
  • crating means being divided into N groups; an f 1 h commutator energizing means for sequentially energizj z ymg m 1mg pulses sald secqnd ing said switch elements and said signal generating O Sal Sal-lip mg gate slgnals passnig means, one of Said groups of said Sig n a1 generating through reed switches in said second group of said means being energized during the time period in 5 2 g g d which one of said switching elements is being ener- 5 z 2 Comprising gized, all of said signal generating means being enera dsecon swlfc mg element each havmg an gized during the time period in which N of said mpu an i Output Switching elements are being energized; signal generating means for producing a first and secmeans for selectively applying the signals from said 0nd slgnali signal generating means to the switching elements in means elierglz
  • the Penod of signal generating means gating signals from a difi Sal d swltc i element 18 elier'glzed ⁇ and ferent one of said groups of switching elements to Secon Slgnal being P F dunng h said output means period that sald second switching element 1s ener- 3.
  • p d Switch is in comprising: swrtc means in said iirst connecting means for intera plurality of p g lines; ruptrng sald connecting means; Pulse generating means for generating pulses on each 40 second conne ctmg mealis for applylpg f Second one of Said Samp1ing1ines nal to the input of said second switchlng element; means for connecting some of said sampling lines to i g gfi gggi g g for pp y g Signals p g l i h of said gi uii i s irfit hzssald Switches m we through said first and second switching elements to a commutator having mounted thereon a plurality of sald Output whereby an output slgnal p cuted representing the status of said switch means. 6.
  • a circuit to provide a switch status and identification signal comprising:
  • a plurality of switching elements each having an outswitch in a group of sampled switches through a put and an input, said elements being divided into wo groups of N elements each; common line to the input of a reed switch in a first Signal generafin means roduci U fi t d d of said groups of reed 1fwitches; d f d 1 set of signals P rs an sewn a fig g gg ggi g 23 gf j jfif i enellgizing means sequent ally energizing said switchin in said commutator, said network supplying a coded e ements first swl tchmg element m the first P f combination of pulses to each reed switch in said groups f finerglzed fonfjwed by fir st swltchnfg other group of rzed switches; element in the second of said groups until all of sald energizing
  • a device for sampling a plurality of switches each switching element of said second group is being enerhaving an input and an output arranged in a plurality gized; of groups comprising: a plurality of switch means divided into N groups, each a plurality of sampling lines; switch means having an output and an input;
  • connecting means applying one signal of said first means for connecting each of said sampling lines to the set of signals to the input of one of said switch means input of one of said switches in each of said groups in each of said N groups of switch means; of switches; a plurality of second connecting means connecting a commutator having mounted thereon a plurality of 7 the outputs of each of said N groups of switch means to the input of a difierent one of said switching elements in said first group of switching elements;
  • third connecting means for applying said second set of signals to the inputs of said second group of switching elements, said third connecting means providing a binary code signal for each of said switch means;
  • fourth connecting means connecting the outputs of said switching elements to said output line, whereby said switch status and identification signal is produced on said output line.
  • a circuit to provide a switch status signal comprising:
  • a switching element having an output and an input
  • energizing means energizing said switching element; operating means operating said signal generating means, said signal being generated during the time period in which said switching element is energized; switch means having an input and an output;
  • first connecting means for applying said signal to the input of said switch means
  • third connecting means connecting the output of said switch means to the input of said switching element
  • fourth connecting means connecting the output of said switching element to the other input of said AND gate, whereby said switch status signal is produced.
  • a circuit for providing a plurality of switch status signals comprising:
  • switching elements each having an input and an output, said switching elements comprising a first and second group of N elements each;
  • signal generating means for producing a plurality of signals divided into a first and second set of signals
  • energizing means sequentially energizing said switching elements, a first one of said switching elements in said first group being energized followed by a first one of said switching elements in said second group until the N element in said second group is energized;
  • operating means operating said signal generating means, all of said first set of signals being generated during the time period in which one of said first group of switching elements is energized and all of said second set of signals being generated during the time period in which one of said second group of switching elements is energized;
  • N groups of switch means each having an input and an output
  • first and second connecting means applying each of said signals produced to the input of a diiferent one of said switch means in each group of switch means;
  • said first connecting means further applying said first set of signals to a first input of said first AND gate
  • said second connecting means further applying said second set of signals to a first input of said second AND gate
  • third connecting means connecting all of the outputs of each group of switch means to the inputs of corresponding switching elements in each of said first and second groups of switching elements;
  • fourth connecting means connecting the outputs of said first group of switching elements to the second input of said first AND gate
  • fifth connecting means connecting the outputs of said second group of switching elements to the second input of said second AND gate
  • sixth connecting means connecting the outputs of said AN.D gates to the inputs of said OR gate.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Magnetic Treatment Devices (AREA)
  • Switches That Are Operated By Magnetic Or Electric Fields (AREA)
  • Electronic Switches (AREA)
  • Control Of Linear Motors (AREA)
  • Near-Field Transmission Systems (AREA)
US360894A 1964-04-20 1964-04-20 Sequential switching device Expired - Lifetime US3362013A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US360894A US3362013A (en) 1964-04-20 1964-04-20 Sequential switching device
GB12006/65A GB1073054A (en) 1964-04-20 1965-03-22 Sequential switching system
DE19651437699 DE1437699B2 (de) 1964-04-20 1965-04-07 Impulsgeber mit mehreren schutzrohrkontakten
SE04882/65A SE325945B (xx) 1964-04-20 1965-04-14
CH547865A CH429839A (de) 1964-04-20 1965-04-15 Elektrische Schalteinrichtung, insbesondere in Fernmeldeanlagen
BE662578D BE662578A (xx) 1964-04-20 1965-04-15
FR13770A FR1430741A (fr) 1964-04-20 1965-04-20 Dispositif rotatif de commutation
NL656504951A NL148735B (nl) 1964-04-20 1965-04-20 Verdelerschakeling.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US360894A US3362013A (en) 1964-04-20 1964-04-20 Sequential switching device

Publications (1)

Publication Number Publication Date
US3362013A true US3362013A (en) 1968-01-02

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Application Number Title Priority Date Filing Date
US360894A Expired - Lifetime US3362013A (en) 1964-04-20 1964-04-20 Sequential switching device

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US (1) US3362013A (xx)
BE (1) BE662578A (xx)
CH (1) CH429839A (xx)
DE (1) DE1437699B2 (xx)
GB (1) GB1073054A (xx)
NL (1) NL148735B (xx)
SE (1) SE325945B (xx)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3495172A (en) * 1967-03-31 1970-02-10 Jordan Ray Davis Electronic cable inspection device and method utilizing and circuits and or circuits

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2162170A (en) * 1939-06-13 Decoder
US2701357A (en) * 1950-12-22 1955-02-01 Bell Telephone Labor Inc Capacitive commutator transmitter
US3105232A (en) * 1959-04-20 1963-09-24 F L Moseley Co Position indication systems
US3174081A (en) * 1962-11-21 1965-03-16 Cincinnati Milling Machine Co Logic nor relay circuits
US3222646A (en) * 1960-08-10 1965-12-07 Sinclair Research Inc Supervisory remote control system
US3264529A (en) * 1963-01-11 1966-08-02 Bell Telephone Labor Inc Magnetically controlled stepping switch
US3275896A (en) * 1964-04-21 1966-09-27 Clare & Co C P Sequential counting circuit using differentially operated realays

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2162170A (en) * 1939-06-13 Decoder
US2701357A (en) * 1950-12-22 1955-02-01 Bell Telephone Labor Inc Capacitive commutator transmitter
US3105232A (en) * 1959-04-20 1963-09-24 F L Moseley Co Position indication systems
US3222646A (en) * 1960-08-10 1965-12-07 Sinclair Research Inc Supervisory remote control system
US3174081A (en) * 1962-11-21 1965-03-16 Cincinnati Milling Machine Co Logic nor relay circuits
US3264529A (en) * 1963-01-11 1966-08-02 Bell Telephone Labor Inc Magnetically controlled stepping switch
US3275896A (en) * 1964-04-21 1966-09-27 Clare & Co C P Sequential counting circuit using differentially operated realays

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3495172A (en) * 1967-03-31 1970-02-10 Jordan Ray Davis Electronic cable inspection device and method utilizing and circuits and or circuits

Also Published As

Publication number Publication date
DE1437699A1 (de) 1968-10-24
NL148735B (nl) 1976-02-16
GB1073054A (en) 1967-06-21
SE325945B (xx) 1970-07-13
NL6504951A (xx) 1965-10-21
BE662578A (xx) 1965-08-02
CH429839A (de) 1967-02-15
DE1437699B2 (de) 1971-10-21

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