US2958028A - Remote control system - Google Patents

Description

Oct. 25, 1960 J. w. SMITH REMOTE CONTROL SYSTEM Filed Nov. 1, 1957 l l i 0 III a llIO.

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o O o m I o, 0 QN 5N h i INVENTOR. JOHN W SM/rH A TTORNEY-S' United States Patent REMOTE CONTROL SYSTEM John W. Smith, Cedar Rapids, Iowa, assignor to Collins Radio Company, Cedar Rapids, Iowa, a corporation of Iowa Filed Nov. 1, 1957, Ser. No. 694,036

2 Claims. (Cl. 318-467) This invention relates to remote control systems and more particularly to such systems employing trinary codes in conjunction with the connecting media between a controlling and a controlled position which are removed from each other.

This application is a continuation in part of my application, U.S. Serial Number 499,649 filed April 6, 1955, entitled Remote Control System, now abandoned.

Remote control systems have been priorly devised whic'n utilized metallic conductors as connectors between the remote controlled position and the local controlling position. Remote control systems using metallic conductors to transmit information between the controlling and the controlled positions possess better operating characteristics than remote control systems which transmit information between the controlling and the controlled positions by means of the atmosphere. However, the better operating characteristics obtained by using metallic conductors as connectors must be balanced by the greater economy of the atmosphere as a connector. Economy in remote control systems using metallic conductors as connectors is necessary for these systems to successfully compete with the atmospheric media connection systems. The necessary economy is best obtained by reducing the number of wires required between the controlling and the controlled positions. This is the obvious place to obtain economy since these wires are normally of considerable length and consequently are the items of the greatest expense. One way in which the number of connecting wires may be reduced in a remote control system using shaft positioning is fully described and claimed in Patent No. 2,476,673 issued July 19, 1949, to R. W. May et al. and assigned to the assignee of the present invention.

The shaft positioning remote control position of May et al. saves on the amount of wires between the controlling and the controlled positions and therefore has become one of the preferred methods of interconnection in remote control systems. However, if a large number of positions are to be selected and remotely controlled, the May et al. system does not sufiiciently reduce the number of wires required as the number of positions becomes increasingly large. Thus, some new method of economically controlling a large number of selection positions in remote control systems is necessary.

This invention is a remote control system which will handle a large number of controlled positions economical- 1y. This invention utilizes metallic conductors as connection media between the controlling position and the controlled position thereby gaining the desired operating characteristics of the metallic conductor type of remote control system. This invention also improves on the economy heretofor possible with the metallic conductor connection type of remote control system.

This invention provides a remote control system wherein trinary code combination indicia is carried on the metallic conductors serving as connectors between the controlling and the controlled units. A manual selec- 2,958,028 Patented Oct. 25, 1960 tion device is located at the controlling unit and rotates to predetermined positions a number of rotating contact elements. These contact elements may assume several shapes and configurations but must always be so designed so that for each position of the manual selection device each individual rotating contact element is positioned in a predetermined relationship with a plurality of stationary contacts. The rotating contacts are connected in accordance with a predetermined and prescribed arrangement to a pluarlity of voltages from various electrical sources. In this invention this plurality of voltages consists of two electrical conditions or voltages, each of which is connected individually to a predetermined one of said rotating contact elements. The third electrical condition for each conductor is an open-circuit condition obtained by the rotating contact elements being configured so that no contact is made between the voltage sources, the rotating element, the specified contact, and the related conductor.

The fixed contacts associated with each of the rotating contact elements are individually connected to the controlled unit by an individual conductor. The voltages which are impressed upon the stationary contacts of the controlling station and the connecting conductors extend operating circuits to combinations of fixed contacts at the controlled unit. These contacts bear a predetermined relationship to the selected position of the control unit. There is a motor responsive to the voltage received from the controlling station which rotates a plurality of pre-cut contact elements until these contact elements bear a predetermined relationship to the fixed contacts of the controlling unit, this predetermined relationship being such that the rotational movement of the motor has positioned the shaft on which the rotating elements are aflixed to correspond exactly to the position of the rotating elements of the controlling position. The proper alignment of the rotating contact elements removes the voltage from the motor to reproduce the selected position at the controlled unit.

This invention makes it possible to provide i code combinations or control positions, where n is the number of wires or conductors between the controlling and the controlled units. There may be a ground return conductor in this type of remote control system which is not included in the number of wires n.

In the specific embodiment of this invention, all possible code combinations are utilized. The dead position as described in the May et al. patent supra resulting from the use of a positive voltage, a negative voltage, and no voltage or ground as the three electrical conditions has been avoided. It is to be realized that other embodiments of this invention may also transmit and utilize 3 code combinations if different voltages are used.

If three wires and a ground return are utilized in this invention, it is possible to control 27 positions. This represents a considerable economic saving over prior remote control systems, which prior systems could only control 2, or 8, positions on three wires and a ground return.

It is an object of this invention to provide a remote con trol system using shaft positioning mechanisms which will economically select any one of a plurality of remote control positions. It is another object of this invention to provide a remote control system using shaft positioning mechanisms which presents continuous selection control information to the controlled unit. It is still another object of this invention to provide a remote control system using shaft positioning mechanisms which will economically present continuous selection control information as a trinary code combination.

It is a still further object of this invention to provide a remote control system using shaft positioning mechanisms which will economically provide a maximum of 3 code positions, where n is the number of code conductors between the controlling and the controlled units.

These andother objects of this invention will become apparent when read in conjunctionwith the accompanying drawing, the single figure of which is a schematic diagram of one illustrative embodiment of this invention.

This invention consists of a controlling unit 2 and a controlled unit 3 which are usually separated'from each other by a considerable physical distance. Selector knob '7 on the controlling unit 2 is rotatable and provides for the selection of any one of 27 positions. The selector knob 7 is mechanically fastened to the shaft 51, which has a plurality of rotating contact elements 8 and 9 also mechanically fastened to it. The rotating contact elements 8 and 9 in this embodiment comprise a pair of pre-cut rotor contact discs which are contoured or cut out to form a configuration of common, interconnected contacts so that an electrical contact, or no contact, is made with three stationary contacts, 8a, 8b, 8c and 9a, 9b, 9c respectively. These three stationary or fixed contacts, as shown in the drawings, are each connected to one of the long line wires or conductors 54, 55 or 56. The rotating contact elements or means 8 and 9 are electrically connected to the sources of voltage and 6. Thus, the rotor contact element 8 always has a positive potential impressed on it to be applied to the selected ones of the three fixed contacts, 8a, 8b and 80, while the cam 9 has a negative voltage impressed on it which may be applied to selected ones of the fixed contacts 9a, 9b and 9c associated therewith. It is an obvious requirement that the rotor contact elements 8 and 9 be so designed that at no time are the sources of positive and negative voltages applied simultaneously to related fixed contacts.

At the controlled station 3, the voltages which are applied from the selection means at the controlling station on connecting wires 54, 55 and 56 are applied to a plurality of interpolating means comprising unilateral conduction devices 14-19, and relay windings 14al9a for actuating relay switches 14b and 19b. The connecting wires are connected to the unilateral conduction devices or diodes which are individually connected to the windings of associated relays I ia-19a. The operation of each relay is thus dependent upon the voltage applied from the connecting Wires 54, 55 or 56. Each of the relays has associated therewith a set of contacts. The contacts are interconnected so that ground potential is connected to at least one of a plurality of fixed contacts. These fixed contacts, 20a-c, Zia-c and 22ac, are associated with the respective rotating contact elements 2.0, 21 and 22. These elements 20, 21 and 22 are cut in a predetermined manner so that if the ground potential from the relay contacts is applied to any one of the nine fixed contacts, such ground potential is connected to the winding 38 of the relay 39. When ground potential is applied to the winding 38, a circuit is completed including the voltage source 4i) to actuate the relay 39. This closes contact 41 and applies voltage from source 40 to the motor 39. Motor 30 then rotates the shaft 52 which has the rotor or common contact elements 20, 21 and 22 connected thereto. Motor 30 will rotate the shaft 52 until such time as the contoured portions of the rotors 20, 21 and 22 are aligned with the fixed contacts so that no ground potential is electrically transmitted through the rotors 20, 2 1 and 22 to the winding 38 of relay 39.

In operation, if it is desired to select position 5, the manual selection knob 7 is rotated until the pointer points at 5. This, then, rotates the shaft 51 and rotors 3 and 9 until the fifth segments of the respective rotors are opposite the fixed contacts 8a and 9a. When this rotation is accomplished, the rotor 8 applies a positive voltage from the source 5 to contacts 8b and 8c, and rotor 9 applies a negative voltage to the contact 9a. With the positive voltage applied to the wire 54, the relay 19a is operated by the current flowing through the diode 19. This moves contact arm 1% to the upper contact and applies ground potential through the upper contact of relay 19a to contact 20c. The negative voltage applied on wire 56 operates relay 14a through diode 14-. This applies current potential through arm 14b to the upper contact of relay 14a and thence to contact 21a. The positive voltage applied on wire 55 operates relay 17a. This applies ground potential through the contact arm 17b to the upper contact of relay 17a thence to contact 2%. This ground potential with the rotors 20, 2d and 22 in the position shown in the drawing is applied through rotor 29 to the winding 38 of the relay 39, and the potential from the voltage source 449 is applied through the contact 41 to the motor 3% thus causing rotation of the shaft 52. The contact elements of rotor 20 will maintain electrical contact with one of contacts Ztia, 2% or 200, thereby maintaining the ground potential on the Winding 38 of relay 39 until such time as the shaft has rotated rotor 20 five positions to the left or until the arrow on rotor 26 points to the contact arm 5. In this position, contacts 20a, 20b and we will be open due to the corfiguration of the rotor 20, and the motor 30 will stop due to the release of relay 39.

The operation of the system for selecting remaining positions is easily traceable and similar to that already described, so it will not be described in detail. Each coding selection or each connecting wire carries a trinary code of various combinations of three different potentials or voltages. It is readily apparent that each wire thus carries only one of three code or voltage conditions and that by combining any three of these Wires with a ground return wire, not shown, the code combinations which may be utilized are 3, where n is the number of connecting wires between the controlling and the controlled units.

The use of diodes to correctly decode the code combinations arriving on the connecting wires is the result of the particular code combination which was selected for this particular embodiment. It is to be understood, of course, that if necessary, voltage value diiferentiating means rather than polarity differentiating means might be used to insure proper operation of the decoding device if various values of voltages are used.

Although this invention has been described with respect to a particular embodiment thereof, it is not to be so limited as changes and modifications may be made therein which are within the full intended scope of the invention as defined by the appended claims.

I claim:

1. A remote shaft positioning system that utilizes trinary coded electrical information comprising a controlling station, a controlled station, three conductors and a ground return circuit for connecting said controlled station to said controlling station, means at said controlling station for applying to said conductors permutations of three electrical conditions, a switching device at said controlled station having three groups of three individual contacts and a group of common interconnected contacts for each of said groups of individual contacts, an actuator drivingly coupled to said switching device for selectively positioning simultaneously said common cont-acts relative to the respective group of individual contacts, an operating circuit for said actuator connected to said common contacts, interpolating means connected to said conductors having three different conditions of operation corresponding to the three different electrical conditions, said interpolating being responsive to the application of different ones of said electrical conditions for extending said opcrating circuit to a different individual contact in different ones of said groups, said switching device having a predetermined position corresponding to each of said permutations to be applied to said conductors, said operat ing circuit being completed through said switching device in response to the application of a different permutation to said conductors to operate said switching device, and said operating circuit being disabled in response to said switching device being positioned in said corresponding position.

2. A remote shaft positioning system comprising a controlling station, a controlled station, a plurality of conductors, a source of negative voltage, a source of positive voltage, a rotary switch assembly at said controlling station, said switch assembly having a plurality of groups of fixed contacts, each group having a contact connected to each of said conductors, a rotor contact assembly for each of said groups, each rotor contact assembly having a plurality of interconnected contacts arranged in a predetermined configuration for engaging upon rotation said fixed contacts of the respective group in diiferent permutations, said sources of voltage being connected individually to different ones of said rotor contact assemblies, means for rotating said rotor contact assembly for applying selectively permutations of positive voltage, negative voltage and open circuit condition to said conductors, a plurality of polarized relay means at the controlled station connected to said conductors, said relay means each having switch means for interpolating said permutation into circuit open and closed conditions, a second rotary switch assembly having a plurality of rotor contact assemblies, each of said second rotor contact assemblies having a plurality of interconnected contacts arranged in a predetermined configuration, an actuator connected to said second rotor contact assemblies, a group of fixed contacts for each of said second rotary contact assemblies, each of said second groups of fixed contacts having a contact selectively connected to said relay switch means, each of said relay means being responsive to the different electrical conditions of positive voltage, negative voltage and open circuit to selectively complete circuits through different respective ones of said second fixed contacts for completing said operating circuit of said actuator, said second rotor contacts being arranged so that for any particular permutation of said electrical conditions on said wires said operating circuit is open for a predetermined position of said second rotor assembly, and said actuator responsive to said second rotor assembly being in any position other than said predetermined position operating to rotate said second rotor assembly to said predetermined position.

References Cited in the file of this patent UNITED STATES PATENTS 2,474,576 Fedotofi? June 28, 1949 2,476,673 May et al. July 19, 1949 2,563,127 McGoffin Aug. 7, 1951 2,601,393 Hammond June 24, 1952 2,755,425 Reid July 17, 1956 2,796,574 Hatfield June 18, 1957 2,808,557 Smith Oct. 1, 1957

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