Changeable Character Display System

Abstract

A changeable message signal comprises a plurality of multiple light source panels arranged in rows for presentation of letters and numerals. The panels are energized in accordance with predetermined patterns and the patterns for the individual panels are changed by operation of stepping switches. A bank of circuit-selecting members such as printed circuit cards may readily be changed to change the information on the panels and each position of the stepping switches energizes a different set of the members to provide a multiplicity of messages in turn.

Description

This invention relates to changeable character signs and particularly to a sign for presenting a series of messages in succession and including an improved arrangement for quickly and easily changing the individual messages to present a different series.

Many types of changing message signs have been provided heretofore; these include signs employing a multiplicity of electric lamps which are energized in patterns presenting the desired messages. The patterns may be provided on punched tapes or cards which determine the lamp circuits to be closed by spring contact fingers positioned to enter holes in the card or tape and make contact to energize the lamps. For some applications it is desirable to present numbers of messages in succession and further to facilitate the changing of one set of messages to another. Accordingly, it is an object of the present invention to provide a message-changing sign or the like including an improved arrangement for the rapid change from one set or series of successive messages to another.

It is another object of this invention to provide a character or message changing electric sign including an improved and compact arrangement for the rapid changing of the programming of the sign.

Briefly, in carrying out the objects of this invention in one embodiment thereof, a composite panel is provided which comprises a plurality of panel units each having a line or row of individual letter or character panels. A multiplicity of electric lamps behind each panel provides the field for the display of a letter or other character. The sign is programmed to present a series of successive messages by operating stepping switches which energize in turn each successive message. Individual stepping switches are provided for each panel and the lamps are energized through readily replaceable conductor members each of which is programmed for a respective character. The stepping switch energizes each conductor member in turn and the corresponding characters are formed on the face of the panel. All of the stepping switches of the composite panel are driven in synchronism and the message on the sign is thus changed upon each operation of the stepping switches. The entire series of messages or any message thereof is changed by selection of a different set of conductor members one for each of the letter panels.

The features of novelty which characterizes this invention are pointed out with particularity in the claims annexed to and forming a part of this specification. The invention itself, however, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of a changeable message sign assembly embodying the invention;

FIG. 2 is an enlarged perspective view of one of the module elements of the sign of FIG. 1;

FIG. 3 is an enlarged perspective view of one of the single panel letter units of the module of FIG. 2;

FIG. 4 is a somewhat diagrammatic wiring schematic of the electric circuit of the sign-changing system of FIG. 1;

FIG. 5 is a perspective view of a stack or bank of detachable conductor members employed with the system of FIG. 4;

FIG. 6 is a perspective view of a base assembly for one of the conductor members of FIG. 5;

FIG. 7 is an enlarged sectional view along the lines 7--7 of FIG. 6;

FIG. 8 is an enlarged sectional view along line 8--8 of FIG. 6; and

FIG. 9 is a plan view of a conductor side of one of the conductor members of FIG. 5.

Referring now to the drawings, the composite message sign illustrated in FIG. 1 is built up from nine units or modules 10 arranged in three vertical and three horizontal rows. Each of the modules comprises four letter or character panels and thus 12 letters may be formed on each of the three horizontal lines of the sign.

As shown in FIG. 2, each of the modules 10 comprises four letter panels 11 arranged on the face of a rectangular box structure. Each of the panel structures 11 comprises a square front opening covered by a light-transmitting screen 12 and behind the screen is a rectangular cell structure or "egg crate" comprising vertical walls 13 and horizontal walls 14 forming seven square cells or compartments in each row along both the vertical and horizontal axes. A multiplicity of lamp bulbs 15 is mounted within the cell structure, there being one lamp in each cell except in the third and fifth cells in the second and sixth rows from the top of the panel. It has been found that it is not necessary to provide lamps in these four cells because all of the characters and letters required in the signs of this embodiment may be formed without the use of lights in these four cells. It will be understood that all the letters of the alphabet, all the numerals and many other characters may be formed by the energization of selected lights in the panels of the single character units 11. Obviously the arrangement of the modules 10 to form sign units and the number of units employed may vary widely depending upon the application for which the sign is intended; furthermore, one or more single units 11 may be added as desired when the design of the sign is other than that which can be built from four panel units.

The apparatus and control circuits for selecting the lamps to be energized and the mechanism for periodically changing the sign by automatic operation of the control is all arranged within the rectangular housings or enclosures comprising the modules. By way of example, there is illustrated in FIG. 4 a circuit and mechanism which may be used for energizing the lights of one of the modules 10 and which may also be employed for controlled energization of the light panels of several modules.

The control system as illustrated in FIG. 4 is arranged to supply the four light panels of a single unit 10. The system includes high and low side bus bars or main leads 17 and 18, respectively, arranged to be connected by a switch 19 to a suitable source of alternating current. The leads 17 and 18 terminate in a terminal box indicated by a dotted rectangle 21 which is provided so that the bars may be connected to a second module unit. Four connection blocks 22, 23, 24 and 25 have been illustrated each being provided for energization of a respective bank or panel of lamps. For purposes of illustration, only the circuit connected to the connection block 22 has been illustrated it being understood that a similar circuit will be employed at each of the other connection blocks. A bank of lamps generally designated by the numeral 26 is connected to the low side or neutral line 18 through leads 27 and 28. The bank 26 comprises a multiplicity of incandescent lamps 30 each having the usual two terminals and individually connected by one terminal to the line 27. The other terminal of each of the lamps is connected to a respective series of contact elements 31 each series comprising a multiplicity of contact elements arranged in spaced relationship. Connection of any one of the elements of a selected series 31 to the high side bus 17 will energize the respective lamp 30. Respective ones of the contact elements in the series 31 are arranged in alignment and also in alignment with a respective row of the contacts 32 which are connected to the bus 17 by operation of a stepper switch 33. Detachable conductor members (not illustrated in FIG. 4) are provided for connecting selected conductors of the series 31 to contacts in the respective series 32. The alignment or arrangement of the contacts in the two series 31 and 32 depends upon the type of conductor member employed and for purposes of illustration the two series of contacts have been shown as arranged in straight line alignment for use with a printed card circuit conductor member described below.

The stepper switch 33 has been illustrated as actuated by a solenoid 34 which is provided with periodic energizing pulses by operation of a pulsing generator 35. The generator 35 includes a motor 36 connected across the lines 17 and 18 and arranged to rotate a cam disc 37 at a preselected rate of speed which determines the timing of the stepping operations of the stepper switch 33. The cam 37 comprises a circular disc having an indentation 38 in its outer periphery and a switch 40 is arranged to ride on the outer surface of the cam 37 and is biased into position against the cam by a spring 41. Each time the cam recess 38 passes under the stem of the switch 40 the switch moves into its closed position connecting a relay coil 42 between the leads 17 and 18 and energizing the coil to close a relay switch 43 and thereby energize a pulse line 44 which extends through the several connection blocks 22, 23, 24 and 25 and is connected to the terminal box 21. It will thus be seen that an alternating current pulse appears on the line 44 each time the switch 43 is closed. Coil 34 of the stepper switch is connected between the pulse line 44 and the neutral bus 18 in a circuit including a diode 46 and a smoothing filter including a series coil 47 and a shunt capacitor 48. It will thus be apparent that the alternating current is rectified and a pulse of direct current applied across the coil 34 thereby attracting an armature 50 to rotate a ratchet wheel 49 and thereby move the stepper switch 33 one position on the occurrence of each pulse. The switch 33 includes a plurality of switch arms 51 all of which lie in the same plane and engage in turn respective contacts in one row of a series of rows of contacts 52. The contacts 52 are connected individually to respective contacts of a respective one of the series 32; thus when the stepper switch is in operation the rows of contacts 52 are engaged successively in turn. When the conductor members are in position the line 17 thus is connected through a lead 54 and the switch arms 51 and contacts 32 to selected ones of respective row of contacts 31, these being the contacts determined by the detachable contact conductor member which has been placed in position on the contacts 31 and 32. In this manner, selected lamps 30 are energized and present a predetermined character on the face of the corresponding panel 11.

The screen 12 covering the face of the panel 11 may be a fine-mesh aluminum screen which acts as a dispersion screen and provides general illumination in the square area of the compartment in which the selected lamp is located.

The stepping switch 33 has been illustrated as of a type comprising a multiplicity of arms and the capacity of these arms is selected so that each arm will easily carry the current required for a plurality of lamps 30, it having been found that in the patterns for the letters, numerals and symbols which appear on the panels 11 sets of two or three lamps are always required when any one of the lamps of a set is required and it is therefore desirable to connect all of the lamps of each set directly by a single switch. A single one of the contact arms 51 thus may energize one, two or three of the lamps 30 depending upon the positions of the lamps selected.

Only three sets of lamp terminals 31 and stepping switch contacts 32 have been illustrated in order to simplify the drawing. It will be understood that the number of sets of lamps and stepper contacts depends upon the design of the individual sign assembly. Thus two or more stepper switches may be required to provide larger numbers of contacts, and each stepper switch may have a greater number of sets of contacts 52. Furthermore the ratchet wheel 49 is provided with the number of teeth or stepping points which correspond to the required number of rows of contacts 52, thus corresponding to the number of pairs of contact series 31 and 32.

When two of the units or modules 10 are connected together, the bus bars 17 and 18 may be connected directly by connecting the terminals of the block 21 to the terminals of the switch 19 of the following module. In other cases it may be desirable merely to connect additional panel units to be operated directly by the pulse generator 35 of one module in which case the units are connected to the three terminals of the block 21 and operate in the same manner as the units connected to any of the blocks 22, 23, 24 and 25 illustrated in FIG. 4.

In FIG. 5 there is illustrated a bank of the aligned series of contacts 31 and 32 provided with conductor members which are printed circuit cards 55 seated in racks 56 on which the groups or series of contacts 31 and 32 are arranged. The cards are readily detachable from the racks and thus a compact bank of detachable conductor members is provided which may readily be changed to introduce different characters in each of the positions of the cards 55.

The structural features of the racks 56 are shown in FIGS. 6, 7 and 8. Each of the racks comprises an elongated hollow insulated base structure comprising longitudinal sidewalls 57 and 58 and top and bottom walls 60 and 61 secured together in a suitable manner and having end plates 62 and 63 with upright groove extensions 64 and 65, respectively. The wall 57 extends above the top 60 and acts a longitudinal guide for the card 55 which may be inserted within the grooves in the upright extensions 64 and 65 and when pressed into position against the top 10 lies in engagement with the contacts 31 and 32 which have been illustrated as spring clips. Each of the clips is connected in the manner indicated in FIG. 4 and the leads for the series of clips 32 have been indicated at 66 in FIG. 8 as extending through the end wall 63 which is provided with an opening 67 for this purpose. As shown in FIG. 7, adjacent contacts 31 in the line from each lamp 30 are connected together by a plug and socket arrangement on the sidewalls 57 and 58 of the racks 56; plugs 69 on conducting bars 69a extending outwardly from the walls 58 and complementary sockets being provided in the opposite ends of the bars which terminate flush with the walls 57. The plugs and sockets of each rack are connected to their respective ones of the clips 31.

The printed circuit card 55 is illustrated in FIG. 9 and comprises a card or plate 68 of stiff insulating material which may be a synthetic plastic; each card 68 is provided with a multiplicity of conductor lines 70 printed on the surface of the card and arranged in parallel spaced relationship to connect spaced points along the right-hand bottom edge of the card to selected points along the left-hand bottom portion of the card card in positions corresponding to the lamp clips to be engaged by the conductor when the card is placed in the rack 56. Each of the cards in the illustrated embodiment provides 22 contact points on the right-hand bottom portion and 20 conductors have been illustrated for connecting the selected series of switch contacts 32 to selected ones of the contacts 31 in alignment therewith. The stack of cards 55 is provided to represent all of the characters which may be required and a sufficient number of duplicates to take care of the probability of duplicate letters or characters in several of the panels 11. With an adequate supply of the cards it will be apparent that the messages to appear on the sign may readily be changed by the simple procedure of changing the cards in the bank illustrated in FIG. 5. This provides a simple and effective arrangement for changing part or all of the information presented on the sign and provides a sign which will present a large number of different messages successively in turn at each operation of the stepping switches.

It will be understood that when the plurality of modules 10 of any sign are to be operated together as a unitary board the stepping switches of the several modules are positioned so that they will operate in synchronism this being effected by starting all of the cams 37 in the same position and energizing all of the motors 36 simultaneously. For some applications a single pulsing unit 35 may be employed to energize the pulsed current line 44 which may then be connected throughout all of the units to be employed in the same manner as the supply lines 17 and 18.

While the invention has been illustrated in connection with a specific embodiment various modifications and applications may occur to those skilled in the art. Therefore, it is not desired that the invention be limited to the specific details illustrated and described and it is intended by the appended claims to cover all modifications which fall within the spirit and scope of the invention.

Claims

I claim:

1. A changeable character display system comprising:

a character display panel having a multiplicity of electric light sources arranged for selective energization to produce visual characters,

each of said light sources having a pair of electric conductors for its connection in an electric power circuit,

means for connecting one conductor of each of said light sources to the same side of the electric power circuit,

the other conductor of each of said pairs of conductors having a multiplicity of contact points connected thereto,

corresponding ones of the contact points of said other conductors constituting a set and being arranged in alignment,

a stepping switch having a multiplicity of switch positions each with at least one contact and means including an arm for movement successively into each of said positions for engaging the respective at least one contact thereof,

means for driving said stepping switch to move said arm with a stepping action,

means for connecting said arm to the other side of the electric power circuit whereby the respective at least one contact of each of said multiplicity of switch positions is connected successively in turn to said other side of the power circuit,

a multiplicity of stationary conductor members each readily and removably mounted in position adjacent said sets for engagement with selected ones of the aligned contact points of any selected one of said sets,

each of said members having conductors positioned for engagement with the respective selected ones of said aligned contact points for connection to respective ones of said light sources for producing a predetermined visual character when energized,

and means for connecting the conductors of each of said members in conducting relationship with a predetermined respective aforesaid at least one of said stepping switch position contacts when the member is positioned with its conductors in engagement with the selected contact points of a respective one of said sets of said aligned contact points whereby when a plurality of said conductor members are each connected to said respective aforesaid at least one of said stepping switch position contacts the operation of said selector switch energizes the conductors of respective ones of said members successively in turn and energizes the respective ones of said light sources for producing corresponding images on said panel.

2. A changeable character display system as set forth in claim 1 wherein said conductor members are printed circuit cards and said sets of contact points are aligned in a straight line, said means for connecting said conductors to said switch contacts being arranged in straight line alignment with the respective sets of contact points for engagement by the conductors of said cards, and said sets being arranged in closely spaced parallel positions whereby said cards are positioned in a close bank.

3. A changeable character display system as set forth in claim 1 wherein said stepping switch has a plurality of said arms aligned with one another and arranged to move together into said positions for simultaneous engagement with a plurality of respective contacts, and said means for connecting the conductors of said members to respective ones of said switch positions contacts comprising spaced contacts connected to respective ones of the contacts in each position of said arms and arranged in alignment with the contacts of respective ones of said sets.

4. A changeable character display system as set forth in claim 1 including a plurality of said character display panels and respective stepping switches and conductor members and adapted for energization by alternating current, said means for driving the respective stepping switches of said panels comprising means for producing a spaced pulse supply of alternating current for synchronously energizing the driving means of the stepping switches of all of said panels and a respective diode rectifier for converting the pulses to direct current to energize the driving means and effect the stepping action of each of said switches.

5. A changeable character display system as set forth in claim 1, including a plurality of said character display panels and respective stepping switches and respective multiplicities of said readily detachable conductor members, said means for driving the stepping switches of said panels comprising means for producing spaced electric current pulses for driving the stepping switches of all of said panels whereby all said switches may be driven in synchronism to energize all said panels simultaneously.