United States Patent 3824723

The display unit comprises an electric lamp located in each of its compartments. Various transparencies, each containing an advertising or educational message thereon, are placed over the compartment openings. A plug board enables certain lamps to be selectively energized. A control circuit provides a sequenced energization of the lamps and also an adjustable display period for each lamp.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
40/463, 40/573, 340/815.55
International Classes:
G09F13/10; (IPC1-7): G09F13/10
Field of Search:
35/1,8R,8A,9R,9B,9A,22R,35C,48R,6 40
View Patent Images:
US Patent References:
3662381LIGHTING DEVICES1972-05-09Steffens
3573792UNIVERSAL DISPLAY PANEL1971-04-06Reed
3414985Teaching apparatus1968-12-10Ashley
3402491Portable visual display device1968-09-24Wagner
3390397PSYCHOLOGICAL TESTING RECORDER1968-06-25Friedlander
3384888Optical apparatus1968-05-21Harnden, Jr. et al.

Other References:

Sylvan, T. P. "Notes on the Application of the Silicon Unijunction Transistor," May, 1961, Pgs. 77..
Primary Examiner:
Schnall, Jerome
Assistant Examiner:
Hum, Vance Y.
Attorney, Agent or Firm:
Peterson, Stuart R.
I claim

1. A multiple transparency display unit and sequencing control comprising means for supporting a plurality of transparencies, illumination means for each transparency, a stepping switch including a plurality of fixed contacts and a movable contact successively engageable with said fixed contacts, means for stepping said movable contact from one fixed contact to the next adjacent fixed contact, a plurality of individually adjustable means for controlling said stepping means to vary the stepping intervals and hence the period of energization of each illumination means, and means connecting at least certain of said fixed contacts in circuit with at least certain of said illumination means whereby those illumination means connected in circuit are energized only when said movable contact engages the particular fixed contact electrically associated with the selected illumination means and whereby only each illumination means is energized for a period determined by the individual adjustment of the particular adjustable means associated therewith.

2. A multiple transparency display unit and sequencing control comprising a cabinet having a plurality of forwardly facing individual compartments open at the front, a lamp disposed in each compartment adjacent the rear thereof so that light therefrom will pass through the open front of the compartment and any transparency associated therewith, means for selectively energizing each lamp, and an adjustable impedance means for each lamp for determining the period that each lamp is energized, said impedance means including an adjustable resistor for each lamp and a capacitor common to the various lamps to provide a resistance-capacitance circuit for each lamp, said means for energizing said lamp including a stepping switch having a plurality of fixed contacts, a wiper arm successively engageable with said fixed contacts, a coil and armature for advancing said wiper arm from contact to contact, and means controlled by said resistance-capacitance circuit for providing pulses to said coil to effect the successive advancement of said wiper arm from contact to contact after a delay period determined by the setting of the adjustable resistor for the particular fixed contact with which the wiper arm is then engaged.

3. A multiple transparency display unit and sequencing control comprising means for supporting a plurality of transparencies, illumination means for each transparency, a stepping switch including a plurality of fixed contacts and a movable contact successively engageable with said fixed contacts, means for stepping said movable contact from one fixed contact to the next adjacent fixed contact, adjustable means for controlling said stepping means to vary the stepping intervals and hence the period of energization of said illumination means, said controlling means including an adjustable resistor connected in circuit between its associated fixed contact and said stepping means, and means connecting at least certain of said fixed contacts in circuit with at least certain of said illumination means whereby those illumination means connected in circuit are energized only when said movable contact engages the particular fixed contact electrically associated with the selected illumination means.

4. A multiple transparency display unit and sequencing control in accordance with claim 3 in which a capacitor is included in circuit with said various adjustable resistors, and a unijunction triggered by the time constant provided by said resistors and capacitors, a silicon controlled rectifier gated by said unijunction transistor and in circuit with said stepping means so that pulses are delivered to said stepping means each time that said rectifier is fired by said unijunction transistor.

5. A multiple transparency display unit and sequencing control in accordance with claim 4 in which said connecting means includes a plurality of conductors each selectively connectable between a fixed contact and an illumination means so that the sequencing of said various illumination means depends upon the selected connection of said conductors with said fixed contacts and also with said various illumination means.


1. Field of the Invention

This invention relates generally to visual display aids, and pertains more particularly to a display unit that can be programmed both as to the order of display presentation and also the time interval for each display.

2. Description of the Prior Art

Visual display devices, of course, are not new. An example of such a device is described in U.S. Pat. No. 3,402,491, issued on Sept. 24, 1968 to Arthur M. Wagner. While the device described in this patent makes provision for changing the display sequence, it must be done by substituting a new disc containing the programming information thereon in the form of arcuate conductive strips. Provision is made for manually interrupting the program sequence. However, to change the program or order in which the transparencies are illuminated requires a substitution of discs that must be previously prepared with the particular program thereon.


Accordingly, one object of the present invention is to provide display equipment that will enable the individual user to change the programming or order of presentation to suit his individual circumstances. More specifically, an aim of the invention is to enable the user to modify or change the program to whatever degree he needs to, depending upon the particular requirements at a given time. Consequently, if the order of disply presentation must be deviated from that which he has personally set up, he can do so very conveniently when practicing the teachings of the present invention.

Another object is to provide flexibility as far as the periods of presentation are concerned. Stated somewhat differently, if it becomes important to have one or more transparencies illuminated for a longer or shorter period than others, this can be accomplished through the simple expedient of manually adjusting a resistor.

Further, an object of the invention is to provide for the multiple illumination of transparencies. In this regard, the user may select more than one transparency so that all so selected will be simultaneously illuminated. Also, the user has the choice of having various lamps contained in the display unit remain de-energized, thereby giving an interval of darkness which can lend emphasis or indicate a change of subject. Coupled with the different periods of display made available to the user, a highly varied program can be devised.

Yet another object of the invention is to provide display equipment that can be manufactured at a relatively low cost, which is compact, and which is readily transportable from one place to another. Consequently, a distinct advantage to be obtained when utilizing the present invention is that a lecturer or salesman who travels can carry with him the display equipment that constitutes the present invention.

Briefly, my invention comprises a stepping switch which is operated upon receipt of various electrical pulses. Provision is made for varying the times at which these pulses are supplied, thereby enabling the various presentation periods to be modified as to the intervals they are made visible to the viewer. By means of a plug board, various lamps can be selected for energization and thereby whatever transparency confronting a particular lamp can be either illuminated or left dark as circumstances dictate. The plug board also permits several lamps to be illuminated simultaneously and others to be left de-energized, thereby providing a considerable amount of flexibility with respect to the presentation of the messages contained on the various transparencies.


FIG. 1 is an electrical schematic view of a multiple transparency display unit and the sequencing control circuitry utilized therewith;

FIG. 2 is a fragmentary perspective view of the upper portion of the display unit appearing at the right in FIG. 1, and

FIG. 3 is a sectional view taken in the direction of line 3--3 of FIG. 2.


Referring now in detail to the display unit and control circuit therefor shown in the drawing, it is to be observed that the display unit diagrammatically appearing in FIG. 1 has been denoted generally by the reference numeral 10. It may contain any number of electric lamps 12. In the exemplary instance, though, six lamps have been rather arbitrarily depicted and have been assigned suffixes a, b, c, d, e and f.

Each lamp has a base 14 (FIGS. 2 and 3) and leads 16, 18 extending therefrom, these leads being shown in FIG. 1 as well. From FIGS. 2 and 3 it will be seen also that the various lamps 12 are housed in a cabinet 20. More specifically, each lamp 12 is contained in an appropriately sized compartment 22 having an opening 24 at the front thereof. There is a top grooved runner 26 and a bottom grooved runner 28, these runners 26, 28 being in alignment with an access slot 30 via which a transparency 32 can be inserted. The particular arrangement for mounting each transparency 32 is unimportant to a practicing of the invention. As a matter of fact, the cabinet 20 may be designed so as to accommodate a single panel having the desired transparencies integral therewith, one such integral transparency overlying or confronting a given lamp 12 much like that illustrated in said U.S. Pat. No. 3,402,491. Still further, while the various compartments 22 are vertically arrayed in FIGS. 1, 2 and 3, it will be appreciated that these compartments can be horizontally disposed or where a greater number of compartments are employed then the various compartments can be arranged both horizontally and vertically to constitute a grid or network of compartments.

At this stage of the description attention is directed to a plug board 34 shown in FIG. 1. While the term plug board has been employed, it will be appreciated that appropriate switches, a barrier strip or a so-called vector board may be used, the function of the plug board being that it is to selectively connect any of the lamps 12a-12f in circuit so that they will be energized at the proper time.

Accordingly, in the form illustrated in FIG. 1, the plug board 34 is wired so as to provide pairs of female contacts 36 and 38. Inasmuch as each pair of contacts 36 and 38 is to be electrically attached through a diode 39 to one of the leads 16, it will be well to use the same suffix designation for the contacts 36, 38 as used in denoting the various lamps 12a-12f. Similarly, additional female contacts are paired and the reference numerals 40, 42 have been used to denote these additional contacts. More will be said presently concerning the means by which power is delivered to the contacts 40, 42. At the present time, though, it will be observed that a plurality of flexible conductors 44, each equipped with male contacts 46 and 48 at their opposite ends. A supply of additional conductors 44 would normally be made available to the user of display equipment of the type herein described, the specific conductors 44 illustrated in FIG. 1 being sufficient for an understanding of the versatility obtainable with my invention.

It will be recognized that the conductor 44 provided with the contact 46a at one end and the contact 48e at the other end thereof supplies an electrical connection between the contact 36a and the contact 40e. Similarly, the conductor 44 having the contact 46b thereon is mated at one end with the contact 38b, thereby supplying power from the other end thereof having the contact 48c which is mated with the fixed contact 40c. Regarding the conductor having the contact 46d thereon, it will be seen that this is mated with the contact 38d at one end and the other end having the contact 48f is mated with the contact 40f. With respect to the conductor 44 having the contact 48ff at one end, it will be seen that by reason of the other end having the contact 48ee that a circuit is effected between the contacts 38f and the contact 42e. On the other hand, an additional conductor 44 is used, reference being made to the one having the contact 46f at one end which is mated with the contact 36f, the conductor in this instance extending to the contact 38c which is made with the contact 48c at the other end of this particular conductor 44. As will be apparent when presenting an operational description, this enables three of the lamps 12 to be energized simultaneously.

Inasmuch as six lamps 12 have been selected to illustrate the invention, six conductors 50, each being distinguished from the other by letter suffix, extend from the paired contacts 40, 42 to a sequencing control circuit indicated in its entirety by the reference numeral 50, more specifically to a stepping switch denoted generally by the reference numeral 54. As is customary, stepping switches are provided with various banks of fixed contacts. In order to keep the description as simple as possible by virtue of having selected only six lamps 12, only six fixed contacts 56 are shown in conjunction with the construction of the stepping switch 54. A wiper arm 58 serves as a movable contact for successively engaging each of the fixed contacts 56a-56f. The wiper arm 58 is conventionally advanced by reason of its mechanical connection to an armature 60 that is actuated by the pulsing of a coil 62. More specifically, each time that an electrical pulse is delivered to the coil 62 it literally moves upwardly to actuate the wiper arm 58 from one contact 56 to the next adjacent contact. A set of normally closed contacts 64 are instrumental in completing the pulsing circuit through the coil 62 as will become clearer as the description progresses.

Before describing further the control circuit 52, it might be well to explain that a conductor 66 extends from the wiper arm 58 through a disconnect switch 68 to another conductor 70. The conductor 70 is connected to a conventional bayonet-type plug 72 which has a pair of prongs or blades 74 and 76. More specifically, the conductor 70 is electrically connected to the prong or blade 74 whereas an additional conductor 78 extends from the blade or prong 76 via a conductor 78 to a conductor 80 connecting with the various leads 18. Although the electrical paths will perhaps be clearer when the operational description is presented, it should be evident, at least to some extent, that the power supplied to the various lamps 12 is done through the various contacts 56 belonging to the stepping switch 54.

Continuing now with the description of the control circuit 52, it will be perceived that a number of conductors 82 are connected to the previously mentioned conductors 50. The same suffix designation will be used and it will also be employed in conjunction with a number of adjustable resistors 84. Each resistor 84 in turn has a conductor 86 leading to the anode of a diode 90, the cathode of the diode 90 being connected to one plate of a capacitor 92. The other plate of the capacitor 92 is connected through the agency of a conductor 94 to the earlier mentioned conductor 78 attached to the plug 72. Depending upon which adjustable resistor 84 is connected into the circuit, and this in turn depends upon which fixed contact 56 is engaged by the movable contact or wiper 58, a time delay or R-C circuit is provided, the capacitor 92 serving to provide the capacitive action in each instance.

The time constant provided by the foregoing resistance and capacitance combination is used in the triggering of a firing circuit now to be described. Accordingly, a conductor 96 leads from the junction between the diode 90 and the capacitor 92 to the emitter of a unijunction transistor 98. One base of the unijunction transistor 98 is connected through a dropping resistor 100 to the conductor 94, whereas the other base of the unijunction transistor 98 is connected through a second resistor 102 to a conductor 104 which leads to one side of a switch 106, the switch 106 being in circuit with a battery 108. The other or negative side of the battery 108 is connected to the conductor 94.

The firing circuit additionally includes a silicon controlled rectifier (SCR) 110. In this regard, it will be noted that the gate of the rectifier 110 is connected directly to the first mentioned base of the unijunction transistor 98, this being the one associated with the dropping resistor 100. Hence, when the unijunction transistor 98 is switched into a conductive state, this provides a triggering or firing pulse for the rectifier 110 with the consequence that it becomes conductive so as to supply a pick-up or energizing pulse to the coil 62 of the stepping switch 54. Of course, the interval or time before the unijunction transistor 98 is triggered is determined by the previously mentioned R-C time constant. This time constant in turn is variable by reason of the particular setting of each adjustable resistor 84.

Having mentioned the plug 72, it should be pointed out that this plug 72 is intended to be connected to an ordinary household outlet and therefore a plug receptacle 112 is depicted. The plug receptacle has a pair of slots 114 and 116 into which the previously mentioned blades 74, 76 of the plug 72 are inserted. The slots 114 and 116 have electrical contacts therein which are connected to conductors 118 and 120 in circuit with an alternating current source 122.


Although the foregoing description perhaps is generally adequate for an understanding of my invention, nonetheless a description of how the invention functions should be of additional help in appreciating the benefits to be gained. Accordingly, it will first be assumed that the appropriate transparencies 32 have been inserted through the access slots 30. Each transparency 32 will contain thereon an appropriate message, perhaps associated with the advertising of a product or the description of how a particular piece of machinery operates. Particularly where a large number of compartments 22 comprise the cabinet 20, there will be occasions where certain transparencies 32 will not be used. It is not necessary to remove these transparencies as the plug board 34 enables the user to energize only those lamps 12 associated with the specific transparencies to be illuminated and thereby viewed. It will be recalled that any preferred number of conductors 44 may be used in conjunction with the plug board 34. Six such conductors are employed for illustrating the particular energizing program that will permit a facile understanding of the invention; others would be made available to the user, though. While all of the lamps 12 are connected so as to be energized, these lamps with the illustrative program are not all individually energized.

With respect to the manner in which each particular lamp 12 is energized, it will be observed that when the stepping switch 54 starts its sequencing action, the first contact to be brought into the circuit is the fixed contact 56a. A circuit can be traced from the plug 72 over the conductor 70, the switch 68 and the conductor 66 to the movable wiper arm 58. From the fixed contact 56a there extends the conductor 50a to the contacts 40a and 42a belonging to the plug board 34. Since only the contact 42a is connected by way of a conductor 44 to the contact 36e it follows that only the lamp 12e is energized at this particular time. Hence, only the transparency 32 associated with the particular compartment in which the lamp 12e is housed will be illuminated.

Depending upon the setting for the adjustable resistor 84a, it will take a little time for the capacitor 92 to become sufficiently charged, this time being influenced by the amount of resistance provided by the resistor 84a, and hence it will trigger the unijunction transistor 98 into conduction at the appropriate time determined by the setting of the adjustable resistor 84. When the transistor 98 conducts, this fires the silicon controlled rectifier 110 which supplies a pulse to the coil 62, the contacts 64 being normally closed so as to complete the pulsing circuit. This causes the armature 60 to be immediately picked up and to move the wiper arm 58 to the next fixed contact 56b. Since only a pulse is forwarded to the coil 62, the armature 60 falls back to its original position, closing the contacts 64 in preparation for the next pulse when it arrives.

Inasmuch as no conductor 44 has been connected with either of the contacts 40b or 42b, consequently there will be no illumination of any transparency during this interval and the resulting lack of any illumination can be used to impart emphasis or to start a different chain of messages.

Of course, when the wiper arm 58 reaches the third contact 56c, then there is an electrical path established to the lamp 12b. There will be an inactive period once again when the wiper arm 58 reaches the contact 58d. However, when the wiper arm 58 engages the contact 56e, then power will be supplied to both contacts 40e and 42e, and since there is a conductor 44 connected to each, power will be forwarded to the lamp 12a and also to the lamp 12f. Owing to the presence of a conductor 44 leading from the contact 36f to the contact 38c, power will also be delivered to the lamp 12c. Thus, at this stage three lamps will be energized, these being the lamsps 12a, 12c and 12f. When the wiper arm 58 reaches the contact 56f, then the lamp 12d will be energized and this will terminate the illustrative sequence.

It should be readily apparent that the wiper arm 58 is advanced in succession from one fixed contact to the next but that the advancement is not necessarily at regular intervals. Actually, the intervals are varied by virtue of the fact that the various resistors 84 vary the time constant of the triggering circuit. The time constant is set for a particular contact 56 and this will remain as a fixed time constant for that particular contact and also any lamp 12 that might be connected through the agency of the plug board 34. Considerable latitude or freedom is provided the user by reason of the various conductors 44 that can be selectively mated as far as their contacts are concerned with those permanently installed on the board 34.

Although a specific description has not been presented with respect to the homing action of the stepping switch 54, nonetheless this is a feature that is conventional. Thus, after the foregoing sequencing has been completed, the stepping switch 54 can be used for repeating the particular sequence as long as that sequence is desired. On the other hand, if at any time the user wishes to adjust the time interval which any particular transparency 32 is illuminated, he is free to do so, it only being necessary that a new setting be adopted for the particular adjustable resistor 86. By the same token, if a different order of sequencing is desired, then the user simply rearranges the conductors 44, either adding to or subtracting from the number of conductors 44 shown for the display program herein described.

It will be appreciated that the various diodes 39 assure that each lamp 12 is isolated from the other as far as the feedback circuit through the variable resistors 84 are concerned to the base of the unijunction transistor 98, without the diodes 39, all of the lamps 12 would be essentially connected together and there would then be only one resistance in the circuit.