US3304541A

US3304541A - Reset means for coded control

Info

Publication number: US3304541A
Application number: US261809A
Authority: US
Inventors: Walter L Probert; Keith N Shade
Original assignee: AO Smith Corp
Current assignee: Smith Meter Inc
Priority date: 1963-02-28
Filing date: 1963-02-28
Publication date: 1967-02-14
Anticipated expiration: 1984-02-14
Also published as: NL6402025A

Description

FQPCB- W67 w. 1.. PROBERT ETAL 3304,43

RESET MEANS FOR CODED CONTROL Filed Feb. 28, 1963 2 Sheets-Sheet l I20 0 A) I I/l L F-TZ/ 5 V j-o 1 3 8 U11 A), 3 [ii w T T l E i P W T/\\/ v: @ET/ I INVENTOR.

\ VVALTER A. PAOBERT Feb. 14, 1967 w.1 PROBERT ETAL 3,304,541

RESET MEANS FOR CODED CONTROL Filed Feb. 28, 1963 2 Sheets-Sheet 2 INVENTOR. MLTER L. PROBERT BY KEITH N SHADE AffOr-Ilnr/s United States Patent 3,304,541 RESET MEANS FQR CUDED CONTROL Walter L. Probert, Erie, and Keith N. Shade, Wesleyvilie, Pa, assignors to A. 0. Smith Corporation, Milwaukee, Wis., a corporation of New York Filed Feb. 28, 1963, Ser. No. 261,809 12 tilairns. (Cl. 34tl147) This invention relates to a coded control input for a coded unit having a reset means for resetting of the input to standby and particularly to a coded unit in which a series of codes are sequentially established with the code identification or input received from a control center.

In various remote control systems, for example, inventory control systems, a coded release unit may be provided at a plurality of remote storage locations. Each of the coded release units in provided with a multiple input control for actuating a release mechanism in accordance with a series of sequentially established controls. Each time a release is desired, the proper code is obtained from the control center for operation of the release mechanism of which is stepped for each positive actuation of an input For example, the copending application of James H. Mc- Gaughey entitled Control System, Ser. No. 88,208 which was filed on Feb. 9, 1961 and assigned to a common assignee with the present application discloses a particularly practical remote inventory control employing a plurality of input buttons for actuating a release mechanism in accordance with a code carried by a perforated code card mounted to open and close a series of control branch circuits. The particular control circuitry shown therein employs a pair of series-connected stepping switches one of which is stepped for each positive actuation of an input and the other of which remains stationary so long as a proper input button is actuated. After the code has been inserted in the release mechanism, a final release button or actuator is provided for completing an inventory release circuit if the input corresponded to the code. If an improper input has been made, whether accidental or fraudulent, the device locks up to prevent subsequent operation of the device. The operator must then call the control center and special personnel must be sent to release the mechanism with the consequent expense and time loss, as well as the unsatisfactory customer relations arising from the annoyance and inconvenience to him. The latter is particularly true if the customer is in great need of a release at the particular moment and must wait upon service from the control center.

It has been suggested that a certain number of wrong code inputs be permitted before the device actuates or prevents further operation. However, when the customer knows this, it allows him to try various combinations in an elfort to eliminate or break the code and thus reduces the security. Additionally, such a system tends to induce a certain amount of carelessness on the part of the operator because he knows all he has to do is call in and get a new code.

The present invention is particularly directed to a means whereby the code can be inserted and then checked before the making of a final circuit.

In accordance with the present invention, a multiple input is employed for conditioning a control circuit. Interconnected therewith is a final control means which is adapted to complete the operative connection of the control circuit, if the control circuit has been properly conditioned. Prior to operation of the final control means the input may be checked and if an erroneous code has been inserted, the input can be reset. After actuation of the final input control, the system prevents further resetting if an erroneous code input has been made. In this manner, it is possible to maintain full security and prevent fraudulent operation while minimizing honest errors and accidental operations and thereby substantially eliminating the disadvantages of the prior systems of control.

In the event maximum security is not desired, it may be possible to allow one or more additional erroneous actuations of the final control means. However, this reduces the security of the system and does carry the disadvantage of the previous systems as heretofore discussed.

The present invention provides a very simple and inexpensive means for allowing reset of a multiple input coded system while maintaining full security and minimization of accidental errors.

The drawings furnished herewith illustrate the best mode presently contemplated for carrying out the invention.

In the drawings:

FIG. 1 is a schematic circuit diagram of a coded control system with certain of the operational components pictorially shown for purposes of simplicity and clarity of explanation;

FIG. 2 is a front elevational view of a multiple code input system with parts broken away to show certain details of construction for switches of the circuit of FIG. 1;

FIG. 3 is an enlarged vertical section taken on line 33 of FIG. 2; and

FIG. 4 is another schematic circuit embodying the present invention.

Referring to the drawings and particularly to FIG. 1, a coded control motor 1 is shown diagrammatically coupled by a dashed line to a cyclically actuated load 2.

For example, load 2 may constitute a gasoline inventory disconnect system such as shown and described in the copending application of Charles D. Erickson which was filed Mar. 13, 1962 with Ser. No. 179,373, now U.S. Patent 3,247,425. In that application, the control system is shown applied to a gasoline inventory control for the conventional service station and includes a release mechanism which allows releasing of preselected subincrements of gasoline from the main storage tank at the service station. The corresponding load 2 in that application constitutes a presettable switch apparatus interconnected with the dispensing means to release an additional increment of gasoline for delivery from a main storage tank. Withdrawal of gasoline from the dispensing means results in reverse actuation of the load 2 such that when the total released quantity has been withdrawn the means are operatively disabled to prevent further withdrawal until the motor 1 has been again actuated.

The illustrated embodiment of the invention includes a motor start solenoid 3 coupled to control a switch 4 which is connected in a series operating circuit with the motor 1 to a suitable AC. power source 5, shown as a transformer having one side grounded to form a common return for simplicity of description. A cycle cam 6 is coupled to and driven by the motor 1. Cam 6 is located to engage and hold switch 4 closed for one cam revolution and thereby maintains energization of the motor for a predetermined cycle after predetermined initial energization of the solenoid 3.

A triggering circuit 7 connects the solenoid 3 to the incoming power source 5 for a selective coded operation thereof. Generally, the operating circuit 7 includes the contacts of an alternating current, hereinafter abbreviated A.C., stepping relay 8 which is responsive to alternating current energization and a direct current, hereinafter a'bbreviated D.C., stepping relay 9 which is responsive to a direct current energization. The stepping relays 8 and 9 must be actuated in a predetermined manner to complete the triggering circuit 7 and connect the solenoid 3 to the power source 5. A card coded control 10 is provided for actuating stepping relays 8 and 9 and includes a bank of ten push button type switches 11 and a pair of

code selection switches

12 and 13 forming a multiple input to the control.

In the illustrated embodiment of the invention, either

code selection switch

12 or 13 and three of the bank of push button switches 11 must be actuated to establish a proper code input and conditioning of the circuit 7 for energizing of solenoid 3, generally in accordance with the control circuit shown in the previously referred to Erickson application. 7

The switches 11 are individually connected one each in circuit with a code card reader 14 in which a code card 15 is mounted. The code card 15 carries a series of code rows each including three code apertures 16 in three of ten possible aligned code positions in the embodiment of FIG. 1. The code card 15 is disposed between a contact plate 17 and ten code reading brushes 18, spaced in accordance with location for apertures 16. The brushes 18 urged into engagement with the contact plate 17 and those aligned with an aperture 15 engage the contact plate.

Contact plate 17 is connected to one side of the power sources and the brushes 18 are connected to the opposite side by

switches

11, 12 and 13 as hereinafter described to control completion of circuit 7.

Each of the switches 11 is shown as a single-pole double-throw variety related respectively to the digits through 9. Each switch 11 includes a spring-loaded contact arm 19, a normally engaged contact 20 and a normally disengaged contact 21. Each of the normally engaged contacts 20 is connected to a corresponding brush 18 except for the digits and 6 wherein the connection of the contact 20 to the brush 18 is made via the

code switches

12 and 13 respectively. Contacts 21 are dead contacts except for digits 5 and 6 wherein contacts 21 are connected to

switches

12 and 13.

Switches

12 and 13 are similar single-pole, double-throw switches and each includes a spring-loaded contact arm 22 connected to the corresponding brush 18, the arm of switch 12 being connected to the brush 18 corresponding to the digit 5 and the arm of switch 13 connected to brush 18 corresponding to the digit 6.

Switches

12 and 13 include a normally engaged contact 23 connected to the normally engaged contact 20 of corresponding switch 11 and a normally disengaged contact 24 connected to the corresponding disengaged contact 21 of the corresponding switch 11. If an aperture 16 is aligned with the brush 18 for switch 12, the corresponding branch circuit may be broken by operation of the switch 12 or the switch 11. However, the switches 11 and 12 cannot both be actuated or the circuit is maintained complete via the connection of

contacts

24 and 21. The brush circuits for switch 13 provide a similar operating limitation.

In the illustrated embodiment of the invention, as in the previously referred to application of C. D. Erickson, the circuits including brushes 18 aligned with apertures 16 must be opened in order to produce a proper operation of the solenoid operating circuit.

Thus, in the illustrated embodiment of the invention, an aperture 16 is shown in the code card 15 for the digit 1. This circuit must be opened as more fully described hereinafter in order to maintain proper actuation of the circuit. Similarly an aperture 16 is shown in the

digit

3, 5, 6 position. The latter circuit may be opened by the corresponding switch 11 or by the code selection switch 12.

The manually actuated switches 12 and 13 are coupled one each to interlock switches 25 and 26 for operation therewith. The interlock switches 25 and 26 are connected in parallel with each other and in series in the solenoid operating circuit such that one must be closed to complete the solenoid operating circuit.

In FIG. 1, switches 11, 12 and 13 are diagrammatically shown including similar push button operators and latch means and one of the switches 11 is described. A preferred mechanical structure is diagrammatically shown in FIGS. 2-4.

In FIG. 1, a push button operator 27 is diagrammatically shown mounted adjacent and in operative engagement with the spring-loaded arm 19. The latch means of FIG. 1 includes a spring-loaded pawl 28 pivotally mounted in holding engagement with an abutment of the operator 27. When an operator 27 is pushed in to move switch arm 19 from contact 20 into engagement with contact 21, the pawl 28 pivots with locking abutment moving into the locking position for holding operator 27 in the actuated position.

A reset plate 29 is shown engaging the lower end of the pawl 27 for releasing the pawl 27 and allowing return of the contact arms 19.

Switches

11, 12 and 13 are held in an actuated position until reset by movement of plate 29, as hereinafter described.

The

switches

11, 12 and 13 are interconnected to control a trigger relay 30 which has a set of contacts 30-1 connected in a control circuit for the D.C. stepping relay 9. Relay 30 includes a coil 31 connected by a common line 32 to all of the contact arms 19 of the switches 11 and the opposite side connected to the power source in series with a manually operated release button switch 33, the paralleled interlock switches 25 and 26 and the stepping relays 8 and 9 to ground.

The D.C. stepping relay 9 includes an operating coil 34 which is connected to a suitable D.C. power source 35, shown as a rectifier connected to a portion of source 5, by the contacts 301. The D.C. stepping relay 9 includes a movable contact arm 36 having a home or a standby contact 37 and a plurality of sequentially engaged dead contacts 38. Each energization and deenergization of coil 34 is operative to effect a movement of the contact arm 36 to the next adjacent contact 38. A reset coil 39 is provided for returning of the contact arm 36 into engagement with the home or initial standby contact 37.

The A.C. stepping relay 8 similarly includes an operating coil 44) connected to the alternating current source 5 in series with a normally open switch 41. A stepping relay contact arm 42 normally engages an initial contact 43 and is coupled to and driven by the operating coil 40 to sequentially engage a series of contacts 44. The third contact 44 removed from the initial contact 43 is connected by a jumper lead 45 to the initial contact 37 of the D.C. stepping relay 9. The A.C. stepping relay 8 includes a reset coil 46 which is connected in series with the D.C. stepping relay reset coil 39 for resetting of the switching circuits as hereinafter described. The switch 41, controlling energization of coil 40, is coupled to each of the push button switches 11 such that each actuation of one of the switches causes a similar closing and opening of the switch 41. Each time a push button switch 11 is operated, erroneously or properly, the A.C. stepping relay coil 40 is energized and moves contact arm 42 to engage the next contact 44.

The solenoid operating circuit 7 which includes relays 8 and 9 is traced as follows. Beginning with the ungrounded side of the A.C. power source 5, the circuit runs directly to the solenoid and therefrom to the release switch 33 in common with the connection of relay coil 31. The circuit then continues through the release button switch 33, the paralleled interlock switches 25 and 26, the contact arm 42 and associated contacts 44 of the stepping A.C. stepping relay 8, jumper lead 45 and the contacts 37 and contact arm 36 of D.C. stepping relay 9 to the ground return.

Energization of solenoid 3 for initiating a cycle of motor operation therefor depends on holding the D.C. stepping relay 9 in standby position while proper actuation of switch 41 moves arm 42 of relay 8 into engagement with the third removed contact 44.

In summary, the coded operation or actuation of the solenoid 3 is as follows, with a code input of A-136 given for the aligned code row.

Depressing or operation of switch 12 for the A selection moves contact arm 22 from contact 23 to contact 24 and thus opens the circuit through the corresponding brush 18 and the exposed plate 17 at the aligned aperture 16. Simultaneously, the switch 25 which is coupled to switch 12 is closed. Actuating switches 11 for

digits

1, 3 and 6 opens the circuit of the correspondingly located apertures.

The actuation of the switches for

digits

1, 3 and 6 also closed switch 41 three times and moved the contact arm 42 of the A.C. stepping relay 8 into engagement with the third removed contact 44. The circuit through relay 8 is thereby established. As a result, when the release button switch 33 is closed the previously described energization circuit for the solenoid 3 is completed and switch 4 is closed. Motor 1 begins to rotate and moves the latching cam 6 into latching engagement with the back side or with the switch 4. The switch 4 will then be held closed until the cam 6 completes one revolution and allows the switch 4 to open.

The closing of the manually operated switch 33 did not complete the circuit through the relay coil 31 of the trigger relay 30 because all of the branch circuits at the card reader 10 are held open by either card or the

switches

11, 12 or 13. As a result, the associated contacts 31-1 remain open and the coil 34 of DC. stepping relay 9 remains deenergized and contact arm 36 engages contact 37 completing the circuit to ground.

However, if an erroneous input has been made, for example, by actuation of switch 11 for digit 2 rather than for digit 1, a circuit is completed between plate 17 and line 32 via the aperture 16 for digit 1. When switch 33 is closed, the coil 31 of trigger relay 30 is energized and related contacts 30-1 close to complete circuit connection of the DC. stepping relay coil 34 to the power source. The associated contact arm 36 disengages the contact 37 and immediately breaks the operating circuit to both the trigger relay 30 and the solenoid 3. As a result, the motor 1 is not driven sufficiently far to latch in switch 4 and establish a cycle of operation.

To allow resetting of the circuit in the illustrated embodiment of the invention, the reset coils 39 and 46 of the relays 8 and 9 are connected in series with one side thereof connected directly to one side of the AC. power source. The opposite side of the series connected resetting coils 39 and 46 is connected in series with a mechanically actuated reset switch 57 to the jumper lead 45 connecting the control contacts of the stepping relays 8 and 9 via a lead 48. Whenever the switch 47 is closed, the circuit through the resetting coils 39 and 46 is completed to ground through the DC. stepping relay contact 37 and arm 36, assuming that an improper coded actuation as heretofore described has not been attempted. If such an erroneous input has been effected, the ground return through the DC. stepping relay 9 is broken and it is then impossible to reset the stepping relays through the circuit of switch 47.

The switch 47 is also shown coupled to the reset plate 39 and thus to the cam 6 of the motor 1 by a conventional dashed line. When a proper input has been established and the cam 6 moves to hold switch 4 closed, the release plate 29 is pivoted sufficiently to reset the push button switches 11, 12 and 13 to the normal extended position and to momentarily close the reset switch 47 and reset the stepping relays 8 and 9 to standby condition but insufiiciently to actuate the AC. stepping relay switch 41; for example, as more fully described with respect to FIGS. 2 and 3.

A key lock switch 49 is provided connecting the resetting coils directly to ground for resetting of the stepping relays 8 and 9. The key for operation of the lock switch 49 is held at and maintained under the control of the control center. If an erroneous input has been established, the control center must be notified thereof in order to have the coding mechanism reset.

In accordance with the present invention, a manual reset button 50 is provided and coupled to the reset plate 29 to manually actuate plate 29 in accordance with the action of the cam 6 and allow manual resetting of the push button switches 11 as well as the code selection switches 12 and 13. Actuation of the reset button 50 also closes switch 47 as a result of the mechanical interconnection to plate 29. However, the resetting coils 46 and 39 of stepping relays 8 and 9 respectively will be energized only if the DC. stepping relay 9 has not been actuated as a result of an erroneous input in combination with a closing of the release button switch 33. The operator may therefore reset the coding mechanism any time prior to actuation of the button switch 33.

In summary, the push button switches 12, 13 and 11 are actuated in accordance with a given code. After all of the appropriate switches have been actuated, the operator can check to see that his input corresponds to the given code. If an accidental error has been made, the manual reset button 50 is actuated, the coding mechanism and the A.C. stepper contact arm 42 return to the standby position. When the desired code input is made, the switch 33 is closed to complete the circuit to solenoid 3. Once the release button switch 33 has been actuated, however, the input must have been proper or the device will lock up and prevent further operation until reset by actuation of the key lock switch 49.

In the illustrated embodiment of the invention, the circuit may be reset if more or less than three push button switches 11 have been operated. For example, if in attempting to close one of the switches 11, the operators finger accidentally pushes a pair of switch buttons even though only one locks in, four steps may be registered in the A.C. stepping relay 8. Even though the input board appears to be in a proper condition, no release will be obtained because of the erroneous number of input steps. The operator can manually reset the switches because the circuit through the trigger relay 30 is now opened at the A.C. stepping relay 8. The system of the present invention therefore maintains flexibility while minimizing service calls. The operator will merely reset the circuit and again insert the proper code and then upon actuation of the push button release switch 33 properly operate the solenoid.

Referring particularly to FIGS. 2 and 3, a mechanical switching arrangement is shown to more clearly illustrate the mechanical operation of the switching mechanism.

Each of the push button switches 11 includes a rodshaped actuator 51 which is journaled within front panel 52 of a housing, not shown, and has an inner head adjacent the housing and an inner tubular spring carrier 53 which projects rearwardly and is journaled in a suitable partition behind the panel. A spring 54 encircles extension 53 and continuously urges the rod-shaped actuator outwardly to the non-actuated position. A cam surface 55 is formed on the inner end of the rod-shaped actuator 51 and includes a button-locking ledge 56 normally engaging the back surface of the panel 52 with the actuator n the non-set position. An L-shaped switch lever 57 is pivotally mounted with a projecting cam follower 58 riding on cam surface 55. A coil spring 59 is disposed between a stationary support and a leg of the L-shaped switch lever 57 to continuously urge cam follower 58 into engagement with cam surface 55. The opposite leg of the L-shaped switch lever 57 is adapted to operate the push button switch 11.

In operation, when the rod-shaped actuator is pushed inwardly, the cam follower 58 rides along the cam surface pivoting lever 57 to close switch 11 until the button locking ledge 56 moves past the cam follower 58. The coil spring 1 then forces the cam follower 58 and lever 57 to pivot outwardly a slight amount and locates the projecting cam follower 58 engaging the button locking ledge 56 and preventing return movement of the rod-shaped actuator 51. The outward locking movement of lever 57 is only a small portion of movement established by cam surface 55 and the opposite leg of the L-shaped switch lever 57 maintains the push button switch 11 in the actuated position described with respect to FIG. 1; i.e., with arm 19 engaging contact 21.

A plate 60 is secured to a pivot shaft 61 supported at opposite ends above the switch bank of push button switches 11 and depends therefrom with the lower edge disposed in the path of the upper end of the head on the rod-shaped actuator. Switch 41 is mounted to one side of switches 11, shown to the left in FIG. 2, and an actuating arm 61 therefor is secured to the pivot shaft 61 and actuates switch 41 each time any of the switch actuators 51 are moved into the latched position. Therefore, each time a push button switch 11 is actuated, the plate 60 is pivoted about its supports. Switch 41 is closed to operate stepping relay 8. Consequently, the alternating current stepping relay coil 40 of the stepping relay 8 is energized for each actuation of a push button switch 11 and contact arm 42 sequentially engages contacts 44.

The push button switches 12 and 13 are similarly constructed and switch 12 is shown and described. Switch 12 is mounted with an outer cap 62 pivotally mounted as at 63 thereon for actuating a switch pin operator 64 for positioning contact arm at the switches. A coil spring 65 is disposed between the outer cap 62 and the switch operator 64 and continuously urges the cap outwardly.

A projecting pin 66 is secured to the cap 62 on the side opposite to the pivotal mounting thereof. Pin 66 is adapted to be disposed within a detent 67 in a latch member 68 upon inward movement of the cap 62 to hold the associated switch 12 in the actuated position. The latch member 68 is slidably disposed within a fixed support 69 and urged upwardly by a spring 70 which is releasably secured to the support 69 and to the latch member 68. A release arm 71 overlies the upper end of member 68 and is keyed or otherwise fixed to a pivot shaft 72, which as most clearly shown in FIG. 3 also supports the levers 57 for pivotal movement thereon. Proper rotation of shaft 72 is effective to depress member 68 to release the cap 62 of switch 12 and return the switch to the standby or non-actuated position. Reset switch 47 is mounted adjacent the underside of member 68 and is actuated, momentarily, as a result of the unlatching movement of member 68 to reset the stepping relays 8 and 9, assuming the circuit through relay 9 has not been interrupted.

A release plate 73 corresponding to plate 29 of FIG. 1 is pivotally mounted on a shaft 74 located below and forwardly of shaft 72. A spring 75 is secured to the release plate 73 and continuously urges the lower end in spaced relation to the levers 57. An actuating arm 76 is secured to the plate 73 and extends downwardly with an offset portion engaging a cam roller 77 secured to the edge of the motor driven cam 6. A reset arm 78 is secured to shaft 72 and projects downwardly into engagement with the back side of plate 73. During each cycle of cam rotation, cam roller 77 engages the offset portion of the depending actuating arm 76 and pivots the arm and attached plate 73 about the shaft 74. The pivotal movement of plate 73 pivots the levers 57 in a counterclockwise direction as viewed in FIG. 3 sufiiciently to disengage the cam follower 58 from locking ledge 56 to release the actuators 51. A

The pivotal movement is also transmitted by the reset arm 78 and shaft 72 to the arm 71 which pivots counterclockwise in FIG. 3 and forces the latch member 68 downwardly whereby the detent 67 moves downwardly below the level of the projecting pin 66. The coil spring 65 causes the cap 62 to move outwardly and open the associated switch 12.

This movement of the reset arm 78 and latch member 68 simultaneously actuates the reset switch 47 to energize the resetting coils 39 and 46 of the stepping relays 8 and 9 and return them to the standby position.

In the illustrated embodiment of the invention of FIGS. 2 and 3, the reset button 50 includes an operating rod 79 journaled in the panel 52 in engagement with the actuating arm 76. When button 50 is pressed, the rod 79 engages and pivots the arm 76 to complete the reset just described resulting from rotation of cam 6.

In the embodiment of the invention illustrated in FIGS. 2 and 3, the push button switches 11 and switches 12 and 13 are releasably locked in place upon initial actuation of each. However, they are mechanically locked in place and can be released through the simple mechanical actuation of the reset button 50. However, the mechanical reset is only effective to reset the coded control circuit if the release button 33 has not been previously actuated with an erroneous input set in the circuit. This is true because of the circuit connection through the DC. stepping relay 9.

An alternative embodiment of the invention is schematically shown in FIG. 4 for controlling an electroresponsive load 79 shown diagrammatically by a labeled block.

In the embodiment of FIG. 4, load 79a is connected to power lines 80 and 81 in series with one side of singlepole, double-throw switch 82 and a set of normally open contacts 83-1 of a trigger relay 83. The opposite side of switch 82 is connected to actuate relay 83 and a coded control circuit 84.

Trigger relay 83 is connected to lines 80 and 81 in series with switch 82 and a set of normally closed contacts 85-1 of a code relay 85 and a disconnect switch 86 for initial energization of relay 83. The relay 83 includes a second set of normally open contacts 83-2 connected across the switch 82. Once relay 83 is energized to close contacts 83-2, it remains energized independently of switch 82 until contacts 85-1 or switch 86 open.

The coded control circuit 84 includes a code card reader 87 for establishing a plurality of branch circuits in accordance with code perforations 88 of a code card 89 as in the previous embodiment. A multiple input switch unit 90 includes control switches in each branch circuit for opening of the code reader completed branch circuits. The switches of unit 90 are mechanically actuated and releasably latched in position as shown in FIGS. 2 and 3 or in any other suitable manner.

Code relay 85 is a dual winding unit wherein contacts 85-1 maintain the open or closed position in accordance with the last energization of a pair of windings 91 and 92. Contacts 85-1 are moved to open position by relay winding 91 and to the closed position by a second winding 92. Winding 91 is connected in series with the paralleled branch circuits across the trigger relay 83 and the contacts 85-1. Thus, when switch 82 is turned to the code position, the coded control circuit 84 is connected across lines 80 and 81. Whether the circuit to relay winding 91 is completed then is determined by the relative setting of the switch unit 90 with respect to the code openings or perforations 88 of code card 89. If not properly related, winding 91 is energized and opens the contacts 85-1 to prevent energization of trigger relay 83 and therefore load 79a.

The second winding 92 of relay 85 is connected to lines 80 and 81 in series with reset switch 93 which may be key actuated such as switch 49 of the first embodiment.

In summary, the code switch unit 90 can be set in one of the plurality of possible positions and reset to a different position until the switch 82 is placed in the code position. This permits the operator to insert the code input and before actuating switch 82 checking the inserted input against the code characters, as in the first embodiment.

The circuitry of FIG. 4 has been substantially simplified for more clearly illustrating the invention. In FIG. 4, the code system could be made inoperative by opening all the switches of switch unit 90. In practice, such possibility would be avoided in any suitable manner; for example, by a mechanical switch interlock to limit the number of individual switches which can be actuated at any one time or by suitable interlocking control switches which demand that one or more of the switches of unit 90 remain open.

The present invention thus provides a very simple and inexpensive structure and system which permits the operator to check his settings and correct them if necessary before pushing a final release control and in this manner minimizes the problem of establishing of accidental operation of the control with an erroneous input. The system furthers the public acceptance and relations between the supplier and the user as well as reduces and minimizes service expense and time. The reset function of the present invention however maintains maximum security in that attempted fraudulent operation of the coded control will result in locking of the control circuit and require servicing.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

We claim:

1. A coded control for a load, which comprises (a) a plurality of input elements having a standby position and an actuated position,

(b) control circuit adapted to be connected to the load and having a comparator means connected to said input elements and to a resettable control means preset for operation of the load by predetermined actuation of said input elements,

(c) circuit switching means to operatively complete said control circuit when said control means is properly preset for operating said load,

((1) separately actuated means to reset said input elements to standby, and

(e) means to reset said control means and coupled to the circuit switching means to prevent operative re- I setting of the control means subsequent to predetermined actuation of said control means.

2. The coded control of claim 1, having (a) said input elements including switches having actuating means and latching means therefor,

('b) said control means including electroresponsive means having a plurality of positions one of which is established by proper code operation of the actuating means and a second of which is established by improper code openation of the actuating means, and

(c) a separate reset means for said electroresponsive mean-s is provided for resetting thereof.

3. A coded control circuit for a load, which comprises (a) a plurality of circuit controlling input elements having a standby position and an actuated position,

(b) a control circuit having input circuit switching means operated by said input elements and a comparator means having coded circuit switching means connected with the input circuit switching means and an output means adapted to be connected to the load and conditioned to operate by predetermined actuation of said input elements,

(c) disabling means connected in said control circuit for selective disabling of the control circuit,

(d) selectively operated control means connected in the control circuit to operatively complete said control circuit when said control circuit is properly conditioned and to actuate said disabling means when said control circuit is improperly conditioned, and

(c) separately actuated mean-s operably independently of the control circuit to reset said input elements to standby for correcting an erroneous operation of the input elements.

4. A coded control circuit for a load,

(a) a plurality of code lines each including an input switch means and code operated switch means,

(b) code means for presettingsaid code operated switch means requiring a selected position of said input switch means,

(c) individual resettable means for actuating said input switch means and including releasable latch means to latch the resettable means in an actuated position,

(d) a main control switch for connecting said code lines to a power source to establish an output control circuit,

(e) load control means adapted to control the load connected in the output control circuit,

(f) disabling means connected in circuit with said code lines and said main control switch and actuated with an erroneous setting of the input switch means in response to actuation of said main control switch, and

(g) means to reset said resettable means.

5. The coded control circuit of claim 4 having,

(a) an electroresponsive control including means actuated by said load control means for controlling the load, and

(b) said main control switch being a two position switch connected to the code lines and to the electroresponsive control and adapted to selectively and alternatively connect the same to a source of power.

6. In a coded input control for controlling an electroresponsive device:

(a) a pair of circuit switching means each having a series of operative conditions, and means being interconnected in a control circuit such that certain of said conditions conjointly control actuation of the electroresponsive device,

(b) means biasing said circuit switching means to predetermined conditions preventing operation of the device,

(c) a multiple input code means presettable in a plurality of combinations and coupled to actuate said circuit switching means, selected actuation of a first of said circuit switching means preventing actuation of the device and selected operation of the second circuit altering means permitting actuation of the device and having selected combinations thereof conditioning said circuit altering means for operation of the device,

(d) a main circuit switching means connected in circuit with said pair of circuit switching means,

(e) means to reset said input code means, and

(f) disabling means connected in said control circuit and responsive to actuation of the main circuit switching means with an improper actuation of the pair of circuit switching means to disable the control circuit.

7. A coded control circuit for a load, which comprises (a) a pair of stepping relay switches having serially connected outputs connected to form a coded control circuit,

(b) multiple code input means coupled to actuate one of said stepping relay switches once for each input,

(c) code means coupling said code input means to the second stepping relay and including comparator means establishing a coded combination of said code input means and actuating the second stepping relay in response to an erroneous actuation of said code input means,

(d) means to reset said code input means, and

(e) electroresponsive reset means connected in an operating circuit with said second stepping relay for resetting of the stepping relay switches.

8. The coded control circuit of claim 7, having (a) reset switch means coupled to said means to reset the code input means,

(b) said electroresponsive reset means includes an operating coil connected between said relay switches and in series with the reset switch means, and

(c) a separate service reset switch means adapted to 1 1 connect the operating coil to a source of power is provided. 9. In a coded input control for controlling energization of a load,

(a) a first electroresponsive switch means having a plurality of switching positions and means biasing the switch means to a first switching position,

(b) a second electroresponsive switch means having a plurality of switching positions and means biasing the switch means to a first switching position,

() a main control switch,

((1) circuit means for operating the load including main control switch and said first and second electroresponsive switch means with the first circuit switch means in the first switching position and the second circuit switch means in a selected position other than said first switching position when conditioned to operate the load,

(e) a plurality of input switches connected for actuating said switch means and presettable in a plurality of combinations,

(f) code means coupled to said input switches to actuate the second switch means once for each actuation of an input switch and including comparator means establishing a coded combination of said input switches and restricting actuation of the first circuit switch means to selected input switches,

(g) means to reset said input switches, and

(h) reset means connected in circuit with the first circuit altering means to disable the circuit means in response to actuation of said main control switch in the presence of a Wrong preset combination of said input switches.

10. A coded control circuit for a load which comprises,

(a) a plurality of manually actuated switches,

(b) latch means to latch said switches in an actuated position,

(0) reset means coupled to set latch means to release said latch means and return said switches to standby,

(d) first circuit altering means,

(e) second circuit altering means connected in circuit with said first circuit altering means to form a control circuit,

(f) a control circuit altering means holding said control circuit inoperative and operable to actuate the control circuit conjointly with the first and second circuit altering means,

(g) code means coupling said push button switches to said first and second circuit altering means for coded actuation thereof,

(h) reset control means connected to said control circuit to reset said circuit altering means to standby, and

(i) means to actuate reset control means.

11. A coded control for a load,

(a) an electroresponsive load control means adapted to control the load,

(b) a coded electroresponsive means connected to control operation of the load control means,

(0) a coded control circuit having a plurality of input means and a comparator establishing a coded input combination for controlling said coded electroresponsive means and having a second electroresponsive means operable if the input means are set in other than the coded setting,

(d) a main control switch means adapted to selectively connect the electroresponsive load control means and the coded control circuit to a source of power, and

(e) means to reset said input means operably independently of the control circuit.

12. The coded control of claim 11 wherein (a) said main control switch is a single-pole, doublethrow switch having one position operatively connected in circuit with the load control means and a second position operatively connected in circuit with the coded control circuit.

References Cited by the Examiner UNITED STATES PATENTS 2,855,588 10/ 1958 Allen. 3,024,452 3/1962 Leonard 340-l64 X 3,234,516 2/1966 Miller 317134 X NEIL C. READ, Primary Examiner. THOMAS B. HABECKER, Examiner.

P. XIARHOS, D. YUSKO, Assistant Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE- OF CORRECTION Patent No. 3,304,541 F b 14, 9 7

Walter L Probert et a1 It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 22, strike out "of which is stepped for each positive actuation of an input" and insert instead which automatically establishes the next code setting. column 5, line 24, for "31-1" read 30-1 column 10, line 29, for "and" read said Signed and sealed this 7th day of November 1967.

(SEAL) Attest:

Edward M. Fletcher, 11'. EDWARD J. BRENNER Attesting Officer Commissioner of Patents

Claims

1. A CODED CONTROL FOR A LOAD, WHICH COMPRISES (A) A PLURALITY OF INPUT ELEMENTS HAVING A STANDBY POSITION AND AN ACTUATED POSITION, (B) CONTROL CIRCUIT ADAPTED TO BE CONNECTED TO THE LOAD AND HAVING A COMPARATOR MEANS CONNECTED TO SAID INPUT ELEMENTS AND TO A RESETTABLE CONTROL MEANS PRESET FOR OPERATION OF THE LOAD BY PREDETERMINED ACTUATION OF SAID INPUT ELEMENTS, (C) CIRCUIT SWITCHING MEANS TO OPERATIVELY COMPLETE SAID CONTROL CIRCUIT WHEN SAID CONTROL MEANS IS PROPERLY PRESET FOR OPERATING SAID LOAD, (D) SEPARATELY ACTUATED MEANS TO RESET SAID INPUT ELEMENTS TO STANDBY, AND (E) MEANS TO RESET SAID CONTROL MEANS AND COUPLED TO THE CIRCUIT SWITCHING MEANS TO PREVENT OPERATIVE RESETTING OF THE CONTROL MEANS SUBSEQUENT TO PREDETERMINED ACTUATION OF SAID CONTROL MEANS.