US2713681A - Impulse generator for debiting of communications - Google Patents

Description

July 19, 195s R7 Al A2 A3 B7 B2 B3 B4- 01 D2 D3 D4 05 R2 R3 R4 R5 IMPULSE GENERATOR FOR DEBITING OF COMMUNICATIONS Filed Dec. 8, 1952 gtfiow ahm nd-mw /MM 2 HM IQTTOR/VE Y United States Patent Hagersten, Sweden, L M Ericsson,

Arvo Treifner, assignors to Telefonaktiebolaget Stockholm, Sweden, a Swedish company Application December 8, 1952, Serial No. 324,736 Claims priority, application Sweden December 19, 1951 1 Claim. (Cl. 340362) The present invention refers to impulse generators of the kind used especially to actuate the communication counters in a telephone system.

According to one debiting method an impulse generator is connected to the counters, which generator con tinuously emits debiting impulses at regular intervals. The first debiting impulse will then be emitted at a time chosen at random during the first period of the communication, whereafter the debiting impulses are emitted at regular intervals. Said time intervals may vary as to their length in dependence on the fee prevailing for the communication, so that for more expensive communications the time intervals are shorter than for cheaper communications. Until now, one or more impulse clocks have been used for that purpose, the clocks having been arranged to emit impulses at determined time intervals. Thus, for each change of the fee the mechanical devices in all the impulse clocks must be changed. Furthermore, the impulse clocks are complicated from a mechanical point of view and consequently expensive.

The present invention relates to an impulse generator which, by means of one single impulse clock emitting one impulse per unit of time, can emit impulses at determined time intervals, said intervals being multiples of the unit of time. According to the invention, this is achieved by the impulse emitting device feeding a number of frequency dividers, each of which emits one or more impulses per multiple of the unit of time. The invention is characterized by a number of relays actuated by the impulses emitted by said frequency dividers, the relays upon operation closing circuits in which are comprised contacts on one or several actuated relays, impulses being fed to said circuits at time intervals, the length of which is a multiple of the unit of time equal to the produce of the multiples of the unit of time at which the relays necessary for the closing of the respective circuits are actuated.

The invention will be described more clearly with reference to the accompanying drawing, which relates to an embodiment. In the figure, IG designates an impulse emitting device consisting of an impulse clock of some kind, RI an impulse relay actuated by the impulse emitting device, and Al-A3, B1-B4, and D1-D5 three relay chains functioning as rotary selectors and moved forward one step for each impulse from the impulse emitting device. R2R5 are relays actuated over contacts on different relays in the relay chains.

For each primary impulse from the impulse emitting device IG the relay R1 is actuated, said relay closing the contacts 21 and 22 and being switched from 24 to 23. If the impulse emitting device IG emits one impulse per unit of time t sec., the output terminal 1 thus receives one positive impulse each tth second over the contact 22. The relay chains A1-A4, Bl-B3, and Dl-DS areactuated over the contacts 23 and 24, said relay chains being constructed according to known principles. Supposing for instance that all the relays of the relay chain A1-A3 are released, the following process takes place upon imis closed through the lower 2,713,681 Patented July 19, 1955 first primary impulse, a circuit winding on relay Al, which impulse is over, a circuit is closed pulse emission. At the Both A1 At the second impulse the current is broken through the upper winding on A1, which releases, whereas A2 remains attracted over the lower winding, When the second impulse is over, a circuit is closed through the upper winding on A2 and the lower winding on A3, and at the third impulse the current is broken through the upper winding on A2 but relay A3 remains attracted over the lower winding. When the third impulse is over, a circuit is closed through the upper winding on A3 and the lower winding on A1 so that during the fourth impulse the relay chain has the same position as during the first impulse. Thus the relay chain steps round on three primary impulses. In the same manner the relay chain B1B4 steps round on four primary impulses and the relay chain Dl-DS on five primary impulses. Thus the relay chains can divide the original impulse frequency by two, three, four or five by providing one relay in the chain Al-A3, two relays in the chain B1-B4 and one relay in the chain D1-D5 with contacts. Thus, relay R3 receives over contact 25 on A1 one impulse for every third primary impulse Whereas relay R2 receives one impulse for every second primary impulse on one hand over contact 26 on relay B1, and on the other hand over contact 28 on relay B3. An impulse is also fed over a contact 27 on relay B1 every fourth primary impulse, and finally relay R5 receives an impulse for every fifth primary impulse over contact 29 on relay D1.

The contacts on relays RZ-RS are combined so that it is necessary to actuate one or several relays in order to obtain a positive impulse on the output terminals 2-12. On for example the output terminal 7 a positive impulse is obtained when the relays R2 and R5 are operated simultaneously, i. e. once for 25:10 primary impulses. The maximal time interval to be obtained with three relay chains according to the figure is 3.4.5=60 times the time interval between the primary impulses from the impulse generator IG. The different impulse trains to be obtained with a device according to the embodiment are shown in the following table.

Time Output gg Operated relays Contact path impulses 1 t 2 2t 3. 3t 4 4t 5.. 5t 6. 66 R2 7. mt R2 8 R3 9 1 5t R3 10 201 R4 11. 302 R2 1 2 Got R3 The impulse generator may naturally comprise an arbitrary number of impulse trains, and therefore the invention is not limited to the shown embodiment.

We claim:

A debiting impulse generator comprising an impulse generating device generating one impulse per unit of time, a plurality of relay chains actuated by said impulses, each of said relay chains being arranged to complete a cycle of operation during one multiple of the unit of time, a plurality of auxiliary relays, contacts on at least one relay of each relay chain arranged to actuate said plurality of auxiliary relays, a number of contacts oneach auxiliary relay, and a plurality of terminals connectable to a source of voltage in series with at least one of said contacts of the auxiliary relays, whereby impulses are obtained at each of said terminals at intervals equal to the product of the multiples of unit of time at which those auxiliary relays are operated which have contacts in said series connection between the voltage source and the respective output terminal.

References Cited in the file of this patent UNITED STATES PATENTS Saunders Oct. 24, 1933 Saunders May 8, 1934 Cook May 30, 1944 Westerveld Nov. 4, 1952

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