US 3659366 A
Display apparatus for presenting data in visual form having panels provided with passages in which display elements, such as balls, are movably positioned and means for selectively moving the balls in their passages between their operative visible positions and their inoperative positions to cause the balls to form or delinate characters. The display apparatus may include a plurality of such panels connected in an endless belt and movable before an opening or window so that the data on more than one panel may be visible at a single time. The means for moving the balls may be jets of air delivered by nozzles mounted on a carriage movable relative to a panel when it is in a predetermined position.
Description (OCR text may contain errors)
United States Patent Woolfolk [151 3,659,366 51 May 2,1972
[ 54] DISPLAY APPARATUS Robert L Woolfolk, Dallas, Tex.
Dow Jones & Company, Inc., New York, NY.
 Filed: Jan. 5, 1970  Appl. No.: 674
Related U.S. Application Data  Inventor:
 Continuation-in-part of Ser. No. 645,022, June 9,
1967, Pat. No. 3,487,568.
 References Cited UNITED STATES PATENTS 3,545,459 12/1970 Phillips ..239/186 X Primary Examiner-Robert W. Michell Assistant Examiner-Richard Carter Attorney-Walter J. Jagmin [5 7] ABSTRACT Display apparatus for presenting data in visual form having panels provided with passages in which display elements, such as balls, are movably positioned and means for selectively moving the balls in their passages between their operative visible positions and their inoperative positions to cause the balls to form or delinate characters. The display apparatus may include a plurality of such panels connected in an endless belt and movable before an opening or window so that the data on more than one panel may be visible at a single time. The means for moving the balls may be jets of air delivered by nozzles mounted on a carriage movable relative to a panel when it is in a predetermined position.
17 Claims, 35 Drawing Figures PATENTEDMAY 2 I972 SHEET 01 0F 15 U. l III-I.
Robert L.Woolfo|k 4% W W X ATTORNEY PATENTEDMAY 2 I972 SHEET 02 0F 15 Fig.4
} INVENTOR Robert L. Woolfolk ATTORNEY PATENTEBMAY 21912 3,659,366
SHEET 03 0F 15 i1 Wm,
INVENTOR .v Fi .l9 1 120k 9 Robert L.Woolfolk Fi g .2 ATTORNEY BY W WW PATENTEDMAY 21972. 3,659,366
sum usnr1s ATTORNEY PATENTEUMAY 2 1912 SHEET 09 [1F 15 QM mm m m V W.
Robert L.Woo|folk & a; ATTORNEY- PATENTEDMY 2 4912 SHEET 13 [1F 15 INVENTOR. Robert L. Woolfolk ATTORNEYS PATENTED MY 2 I972 SHEET l 0F 15 INVENTOR Robert L.Woolfolk My ATTORNEY PATENTEDHAY 2 I972 sum 15 0F 15 mmm INVENTOR.
I I V an) wa Robert L.Woo|fo|k k W XW ATTORNEY DISPLAY APPARATUS CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of copending applieation Ser. No. 645,022 filed June 9, 1967, by Robert L. Woolfolk, now US. Pat. No. 3,487,568 granted Jan. 6, 1970.
This invention relates to display apparatus and more particularly to a display apparatus for visually presenting data or information.
An object of this invention is to provide a new and improved display apparatus for visually displaying data which has a plurality of discrete elements mounted on panels for movement between inoperative positions wherein they are not visible to the viewer and operative positions wherein they are visible.
Another object is to provide a display apparatus having a panel provided with a plurality of passages in which are disposed display elements, such as balls, which are movable between front or outer operative positions at the front side of the panel wherein they are visible and rear or inner inoperative positions wherein they are not visible.
Still another object is to provide a display device wherein the balls of a panel are held in their operative and inoperative positions by gravity. I
A further object is to provide a display apparatus wherein the balls of a panel are movable between their operative and inoperative positions by an operator means or assembly which is movable relative to the panel and has means for directing jets of air at selected balls to move them between their operative and inoperative positions as the operator means moves past the panel.
A still further object is to provide a display apparatus which includes a plurality of panels connected in an endless belt and forming a display assembly movable in a close path which includes a front vertical view portion so that the data displayed by a plurality of panels in the front vertical portion is visible to a viewer.
Another object is to provide a display apparatus which permits the display of a large amount of data at any one time.
A still further object of the invention is to provide a display apparatus including a panel having a plurality of spaced groups of passages, each of the groups comprising a plurality of passages arranged in vertical columns and horizontal rows, balls movably mounted in the passages of each group which in operative positions are adapted to form or delineate different characters, such as letters or numerals, and a carriage movable relative to the panel and having nozzles aligned with the horizontal rows of passages for selectively delivering jets of air to the ends of the passages of each column as the nozzles move therepast.
A further object is to provide a display apparatus wherein the carriage and'the panels have index means for permitting operation of the noules only when the nozzles move into alignment with the passages of each column of passages.
A still further object is to provide a display apparatus wherein the panel assembly is movable in a closed path and wherein each of the panels is provided with index means and the carriage is provided with sensor means for arresting movement of each panel when it moves in proper alignment with the nozzles of the carriage.
Another important object of the invention is to provide a display apparatus for translating data received in digital fonn, as forexample, over teletype lines, into visible alphanumeric characters.
Still another object is to provide control means for controlling operation of the carriage and its nozzles and of the display assembly or belt of panels in accordance with the signals received over a teletype line.
Additional objects and advantages of the invention will be readily apparent from the following description of certain preferred embodiments, when read with reference to the accompanying drawings, wherein:
FIG. I is a front partly schematic view, with some parts broken away, of a display apparatus embodying the invention;
FIG. 2 is a vertical partly schematic partly sectional view taken on line 2-2 of FIG. I;
FIG. 3 is a front enlarged fragmentary view of a panel of the display apparatus illustrated in FIGS. 1 and 2;
FIG. 4 is a schematic, fragmentary partly sectional view, with some parts broken away, taken on line 4-4 of FIG. 3;
FIG. 5 is a schematic view of the display assembly or belt of panels of the apparatus;
FIG. 6 is an enlarged, partly schematic sectional view taken on lines 6-6 of FIG. I;
FIG. 7 is a partly schematic perspective view of the operator means or carriage of the apparatus illustrated in FIG. I;
FIG. 8 is an enlarged front view of the carriage of the display apparatus;
FIG. 9 is a vertical sectional view taken on line 9-9 of FIG.
FIG. 10 is an enlarged fragmentary partly sectional view taken on line 10-10 of FIG. 8;
FIG. 1 l is a plan view of an orifice plate of the carriage;
FIG. 12 is a schematic, side view, with some parts broken away and in section, of a modified form of the display apparatus illustrated in FIG. 1; 1
FIG. 13 is en enlarged fragmentary sectional view taken on line 13-13 of FIG. 12; I
FIG. 14 is a fragmentary perspective view of a nozzle pipe of the display apparatus illustrated in FIGS. 12 and 13;
FIG. 15 is a functional block diagram of a control circuit for the apparatus illustrated in FIGS. 1 through 11, and for the apparatus illustrated in FIGS. 12 through 14;
FIG. 16 is a fragmentary partly sectional view of another modified form of the display apparatus takenvon line 16-16 of FIG. 17;
FIG. 17 is a partly schematic sectional view taken on line 17-17 ofFIG. 16; v
FIG. 18 is an enlarged fragmentary sectional view of a panel of the apparatus of FIG. 16;
FIG. 19 is a fragmentary horizontal sectional view similar to FIG. 16 of another modified form of the display apparatus embodying the invention;
FIG. 20 is an enlarged partly sectional view of one of the display elements of the display apparatus illustrated .in FIG. 19;
FIG. 21 is a front view of a further preferred form of display apparatus embodying the invention;
FIG. 22 is a top view of the apparatus illustrated in FIG. 21;
FIG. 23 is a partly sectional view, with some parts broken away, taken on line 23-23 of FIG. 21;
FIG. 24 is a sectional view, with some taken on line 24-24 of FIG. 23; I
FIG. 25 is an enlarged partly sectional view taken on line 25-25 of FIG. 24;
FIG. 26 is a sectional view, with some parts broken away and others removed, taken on line 26-26 of FIG. 26;
FIG. 27 is a fragmentary sectional view taken on line 27- 27 of FIG. 24;
FIG. 28 is an enlarged fragmentary front view of panels of the display or panel assembly of the apparatus illustrated in FIGS. 21 through 27;
FIG. 29 is a fragmentary partly sectional view taken on line 29-29 of FIG. 28;
FIG. 30 is an enlarged sectional view taken on line 20-20 of FIG. 28;
FIGS. 31A and 31B are a functional block diagram of the control circuit of the apparatus illustrated in FIGS. 21 through 30;
FIG. 32 is a diagrammatic illustration of a buffer storage register of the control circuit illustrated in FIGS. 31A and 31B; and,
FIGS. 33A and 33B are a diagrammatic illustration of the control circuit of the motors for moving the carriage and the panel belt of the apparatus illustrated in FIGS. 21 through 32.
Referring to FIGS. 1 and 2 of the drawings, the display apparatus 20 includes a housing 21 having a horizontal bottom parts broken away,
wall 22, a top wall 23, a rear wall 24, side walls 26 and 27, and a front wall 28. The front wall has a display aperture or window 30 therein.
A light case 32 is rigidly secured to the front wall 28 about the window 30. The case 32 includes side sections 35 and 36, top and bottom sections 39 and 40 which extend divergently forwardly relative to one another, top and bottom front sections 41 and 42 which extend convergently rearwardly from the front edges of the top and-bottom sections, and side front sections 44 and 45v which extend inwardly from the side sections 35 and 36, respectively. The top and bottom sections 39 and 40 may have flanges 47 and 48, respectively, which abut and are rigidly secured to the front housing wall by screws 33. The front sections 41, 42, 44 and 45 define an aperture or window 49 which opens to the window30 of the housing.
A support frame 50 is mounted in the housing 21 and includes a pair of vertical support plates 51 and 52, and top and bottom angle members 54 and 55 which extend between the two support plates and are rigidly secured thereto as by welding. The support plates may also have angle members 56 at their outer peripheral edge portions similarly secured thereto.
The peripheral angle members have flanges which abut adjacent walls of the housing and are secured thereto in any suitable manner,- as by'bolts 57 in the case of the peripheral angle members at the upper and lower ends of the support plates and as by screws 58 (FIG. 6) in the case of the peripheral angle members which abut the fi-ont and rear walls. The support plates have forward portions which extend forwardly through the window 30 of the housing and into the light case. 7
A plurality of light tubes 60 are mounted between the support plates 51 and 52 in the upper portion of the light case 32. The ends of the tubes 60 as disposed in the usual sockets 62 located above the lower edge of the top'flange 41 of the light case and below a reflector plate 63. The light emitted by the tubes is directed downwardly and rearwardly through the housing window 30. The emitted light is'of a predetermined wave length outside the range of visible light.
-A pair of similar light tubes 64 is located between the support plates 51 and 52 below the top edge of the bottom front flange of the light case 32. The tubes 64 are held in position by the usual sockets 65 above an arcuate reflector plate 66. The light emitted by the tubesis directed by the plate 66 upwardly and rearwardly through the housing window.
A movable display assembly (FIGS. 3-5) is mounted between the support plates 51 and 52 by means of a top drive shaft 76 and a bottom idler shaft 77. These shafts are carried by the plates in suitable bearings 78. The display assembly 75 includes a plurality of panels 80 connected by horizontal pivot shafts 81 in a manner to be described in greater detail below. A pair of sprockets 82 rigidly secured to the drive shaft 76 have spaced radial arms 84 in whose outer recesses 85 are receivable the rollers 87 mounted on the pivot shaft 81. It will be apparent that as the drive shaft 76 is rotated in a counterclockwise manner, as viewed in FIG, 5, the engagement of the sprocket arms with the rollers 87 causes the front visible portion of the display assembly (the right hand portion, as viewed in this Figure) to be moved upwardly. The drive shaft 76 is driven by a suitable electric motor 88 (FIG. 1) which is rigidly secured to the support plate 51 by bolts 89. The motor 88 is preferably of the synchronous type having a permanent magnet armature in order that the rotation of the drive shaft is immediately arrested when the stator windings of the motor are disconnected from a source of alternating current. The idler shaft 77 is provided with similar sprockets 90 rigidly secured thereto whose radial arms 91 are provided with recesses or sockets 92 in which the rollers 87 of the pivot shafts are receivable. The sprockets of the drive and idler shafts are aligned vertically and inwardly of the support plates.
The panels 80 are connected by the pivot shafts 81 to'form an endless belt which travels in a closed path. This path has a front portion A in which the panels move upwardly adjacent to and past the housing window 30, an upper portion B in which the panels move rearwardly, a rear portion C in which the panels move downwardly and a bottom portion D in which the panels move forwardly. The panels are guided in their movement not only by the sprockets on the drive and idler shafts but also by guide rollers 94 rotatably mounted on the opposite ends of 'the pivot shafts and movably disposed in the guide recesses 95 of the support plates. The guide recesses are of somewhat greater width than the diameter of the guide rollers. v v
Adjacent top and bottom edges of adjacent panels are provided withslots 96 and tongues 97, the tongues of one panel being received in the slots of the other. The pivot shafts 81 extend through such slots and through bearings 98 carried by the tongues.
It will be apparent that the display assembly is guided and held in a desired path of movement by the engagement of the sprockets on the drive and idler shafts with the rollers 87 of the pivot shafts and also by the engagement of the guide rollers with the surfaces of the support plates defining the guide recesses.
When the panels are located in the front portion A of the path of movement of the display assembly 75, the outer sides of all such panels, except the lowermost panel located in the path portion A, are visible to view through the windows 49 and 30 of the light case and the housing, respectively. A
Each of the panels may be formed of a planar outer member and a planar inner member 111 secured to one another in any suitable manner, as by adhesive, bonding and the like. The panels have transverse passages 112 therethrough which are formed by the divergently outwardly sloping bores 113,and 114 of the outer and inner panel members, respectively, so that the opposite portions of the passages of a panel slope downwardly and outwardly from the middle of the panel when the panel is in the front view portion A of the path of movement, and slope upwardly and outwardly when the panel is in the rear portion C of the path of movement. The outer ends of the passages are reduced as by the lips 1 16 and 1 17 to prevent movable elements located in the passages from moving out of the passages.
The bores 113 constitute outer portions of the passages since they open outwardly at the outer face or surface of the path of movement of the panels. The bores 114 constitute inner portions of the passages since they open inwardly relative to the path of movement of the panels.
As best illustrated in FIGS. 4 and 5, when a movable element 120 is in either its outer operative position or its inner inoperative position within the panel, i.e., in the outer or inner portion of a passage at the time the panel is in the vertical por tion A of the path of movement, it is held in such position by gravity, and its outward movement in the passage is limited by alip1l6or 117.
As a panel proceeds rearwardly and upwardly and then rearwardly and downwardly in the top portion B of the path of movement, the elements move due to the force of gravity first to their inner position wherein their movement is limited by the lips 116 and then to the middle of the passages. The elements remain in the middle of the passages during the downward movement of the panel in the rear portion C of the path of movement. As the panel thereafter proceeds downwardly and forwardly and then forwardly and upwardly, all of the elements move to their outer positions in the passages of the panel wherein their outward movement is limited by the lips 116. The arrangement is such that as each panel is moved to a vertical position at the bottom end of the front view portion A of itsmovement, all of the elements carried by the panel are in their outer operative positions. lf thereafter any such element is moved, as will be described below, inwardly in its panel passage to its inner inoperative position, it will be held in such inoperative position by gravity as long as the panel is in the front view portion of the path of movement.
If, as illustrated in FIG. 3, the panels are designed to display alpha-numeric characters, the passages are arranged in longitudinally spaced character groups G1, G2...Gn, the passages of each group being arranged in a plurality, for example, 5, vertical columns C1-C5 and a plurality, for example, 7, rows Rl-R7.
Each panel has a bottom longitudinal slot 121 (FIG. 4) through which a portion of a reflective strip 122, secured between the two panel members and 111, is exposed. The reflective strip may be disposed in a longitudinal recess 124 in the outer panel member 110. A similar strip 125 of reflective substance is located above the passages 112 of each panel and is disposed in a longitudinal recess 126 in the outer panel member 1 10. As best shown in FIG. 3, the portions of the strip 125 in alignment with the columns C1-C5 of the passages are exposed through slots S1, S2, S3, S4 and S5 in the outer panel member 110.
The reflective strip 122 is used as an index means to control the vertical positioning of each panel relative to a movable carriage (FIG. 4) as the panels move successively into alignment with the carriage so that the outer ends of the passages in the rows R1-R7 will be in proper alignment with the nozzles N1-N7, respectively, of the carriage. The portions of the reflective strip 125 exposed through the slots Sl-SS are used to control the operation of valve means associated with the nozzles. As will become more fully apparent hereinafter, the valve means control flow of gas under pressure to the nozzles as the nozzles move successively into alignment with the outer ends of the passages of each column Cl-CS.
The carriage 140 is movable horizontally, in front of the lowermost panel in the portion A of the path of movement of the panels, on a pair of slide bars 141 and 142. The slide bars 141 and 142 extend through openings 143 in the support plates 51 and 52, and the opposite ends of the slide bars are rigidly secured to suitable brackets 144 and 145, respectively. These brackets are disposed outwardly of the support plates and are secured to the bottom housing wall 22. The movement of the carriage on the slide bars is controlled by the sprocket chain one of whose ends is secured to one side of the carriage by a bolt 151 which extends through suitable aligned apertures in one end link of the sprocket chain and the brackets 154 (FIG. 7 secured to one side of the carriage. The other end of the chain 150 is similarly secured to the opposite side of the carriage by a bolt 155 and brackets 156.
The sprocket chain 150 extends about an idler sprocket rotatably mounted on a bracket 161 secured to the housing bottom wall 22 outwardly of the support plate 52. The chain 150 proceeds about a drive sprocket 163 rigidly secured to a drive shaft 165 (FIG. 6) which is rotatably mounted in suitable bearings on a pair of support brackets 166 and 167. The drive sprocket shaft 165, and therefore, the drive sprocket 163, are driven in a clockwise direction, FIG. 1, by a motor 170 (FIG. 6) when the electric clutch 171 is energized. The clutch may be of any suitable type, for example, the type available from American Precision Industries, Inc. of Buffalo, New York, under Model No. API LLCF-20, and is mounted on the bottom housing wall by a bracket 172. The clutch 171 when energized causes a pulley 174 to be rigidly connected to the drive shaft. A belt 175 connects the pulley 174 to a pulley 176 on the drive shaft 177 of the motor.
The drive sprocket 165 is rotated by the motor 170 in a counterclockwise direction, FIG. 1, when an electric clutch 180, which may be identical to the clutch 171, is energized. Energization of the clutch 180 connects a pulley 182 to the drive sprocket shaft. The pulley 182 is connected to a pulley 184 rigidly secured on a reversing shaft 185 by a belt 186. The reversing shaft 185 is rotatably mounted on pillow blocks 187 and 188 affixed to the mount plate 189 of the motor. A gear 190 on the reversing shaft 185 meshes with a gear 191 on the motor drive shaft 177.
It will be apparent that since the diameter of the pulley 174 is greater than that of the pulley 176 while the diameter of the pulley 182 is smaller than that of the pulley 184 and the diameter of the gear 190 is smaller than that of the gear 191, the shaft 165, and therefore the drive sprocket 163, will be rotated at a slower speed in a clockwise direction than in a counterclockwisedirectionLThus,the carriage 140 will move from right to left, FIG. 1, at a much greater speed than it is moved from left to right. Due to the provision of the two electrically operated clutches 171 and 180, the motor 170 is energized continuously during the operation of the apparatus and, depending on which clutch is energized, will move the carriage relatively slowly from left to right and very rapidly from right to left.
An electrically operated brake 195 (FIG. 6) is mounted on the support bracket 166 and is provided to brake or arrest the rotation of the shaft 165 when the carriage 140 approaches the extreme limits of its movement to prevent the carriage from forceably engaging either of the brackets 144 and 156. Similarly, an electric brake 196 (FIG. 1) is mounted on the support plate 52 and is provided to arrest rotation of the shaft 76, and therefore the upward movement of the front view portion of the display assembly, when a bottom panel thereof moves into proper alignment with the nozzles of the carriage. The brakes 195 and 196 may be of the type commercially available from American Precision Industries, Inc. under Model No. LLBF-20.
The panels 80 are coated with a black, light absorbing nonreflective substance, or are formed of such light absorbing substance, so that the light emitted by the light tubes 60 and 64 and impinging on the outer surfaces of the panels is absorbed. The balls or display elements, however, are of a substance which fluoresces when the light of predetermined wave length, for example, the so-called black light, emitted by the light tubes impinges thereon. The spherical shape of thedisplay elements, which may be relatively small, for example, three-sixteenth of an inch in diameter, and the light contrast between the balls in their outer visible positions and the panels, causes the characters formed or delinated by such balls to be clearly visible and the characters so formed to be sharply defined. I
The carriage 140 may include a substantially rectangular housing 201 (FIGS. 7-9) having suitable bearings 202 and 203 secured to its opposite end walls 204 through which extend the slide bars 141 and 142, respectively. The front wall 205 of the housing may have a flange 206 which telescopes over the end, top and bottom walls of the housing and is secured thereto by screws 207. The front wall has a rectangular opening 208 defined by an inwardly extending continuous flange 209 having a continuous stop flange 210 at its inner edge which limits inward movement of a manifold assembly 212 into the housing through the opening. The manifold assembly includes an orifice plate 214 having the seven vertically spaced apertures 215a-g of the nozzles, N1-N7, respectively. The nozzles Nl-N7 may be integral with the orifice plate 214 and extend forwardly therefrom. The apertures 215a-g open to grooves 216a-g, respectively, in the inner surface of the orifice plate which extend to and are in communication with the passages 217a g respectively, of a valve mount plate 218. Solenoid valves 220a-g are secured to the valve plate in any suitable manner, as by screws 221. The outlet ports 219a-g of the valves are aligned with and in communication with the valve mount ports 217a-g, respectively, and their inlet ports are open to the interior of the manifold housing 224. The manifold housing is also substantially rectangular in form and has a back wall 224a and side walls 224b provided with an external outwardly extending flange 226 which is adapted to engage the flange 210 of the carriage front wall 205. The orifice and valve mount plates and the manifold housing are secured to the carriage front wall by bolts 227 which extend through aligned apertures in the orifice and mount plates and the abutting flanges of the front wall and the manifold housing. A gasket 228 seals between the plates about the grooves of the orifice plate and has slots 229a-g which are aligned with the grooves 216a-g, respectively. A second gasket 230 seals between the flange 210 and the valve mount plate.
The valve housings are sealed to the mount plate about the passages 217a-g and.219ag by a suitable sealing compound,
' nuts 238, a gasket or seal ring 239 and a washer 240. The nipple 236 also extends through a suitable aperture in the rear wall 241 of the carriage housing and is threaded in the adjacent end of an inlet elbow 242. The nipple is secured to the rear wall 241 of the carriage housing by nuts 243 and washers 245. A flexible conduit 246 is secured in any suitable manner as by fitting 247 to the other end of the elbow 242. The flexi- In use, assuming that the carriage 140 is at its extreme left hand position, FIG. 1, the panel A1 (FIG. 4) in the front portion of the path of movement of the display assembly is a position wherein the nozzles N1-N7 are in horizontal alignment with the rows of passages 112. The carriage motor 170 is energized, the motor 88 is de'energized, all of the balls in the panel Al-are now in their outer from positions in the passages 112,
' all of the solenoid valves are closed and air under pressure is ble conduit may extend through a suitable aperture in a wall of the display housing 21 to a source of compressed air under pressure (not shown) located externally of the display apparatus.
The front wall 205 of the carriage housing 201 has a sensor assembly 250 mounted thereon. The assembly 250 includes a pair of electric light bulbs 251 carried in suitable sockets 253 on the front wall and a photocathode tube 255 carried in a socket 256 also secured to the front wall. The light bulbs 251 and the photocathode tube 255 are aligned vertically, and the light bulbs direct their light convergently outwardly so that each time the carriage 140 is in alignment with one of the slots S1-S5 (FIG. 3) of an outer panel member 80, the light from the bulbs is directed through such slot at the reflective strip 125 and is reflected back to the photocathode tube. The photocathode tube provides a column position signal to a suitable control circuit which then causes selected solenoid valves to be energized as the nozzles move into alignment with passages 133 of the column under such slot.
A group sensor assembly 260 (FIG. 8), which includes a pair of electric light bulbs 261 and a photocathode tube 263, is similarly secured to the front wall 205. The photocathode tube 363 provides a voltage or signal of a control circuit each time it moves into alignment with one of the slots 81-85 of a panel 80. The group sensor assembly 260 is spaced from the column sensor assembly 250 a distance equal to the distance between the midlines of the. adjacent slots of each group Gl-Gn of passages of a panel but is spaced therefrom a distance less than the distance between adjacent slots of adjacent groups. For example, if the photosensor assembly 250 is in alignment with the slot S1 of the character group G1, the group sensor assembly 260 will be aligned with the slot S2. However, when the group sensor assembly 260 is positioned in alignment with the first slot S1 of a group G, such as that of Group G2, FIG. 3, the column sensor assembly 250 will be positioned between the slot S5 of group 1 and the slot S1 of group 2. The column sensor assembly 250 will thus not transmit a signal to the control circuit when the carriage is in this position.
The sensor assemblies 250 and 260, as will be explained in greater detail, cause opening of preselected valves as the nozzles move into successive alignment with the five columns of each group of passages and also provide a signal to the control circuit as the group sensor assembly moves into alignment with the first column C1 of such group.
A panel position sensor assembly 270 (FIGS. 7-9) on the carriage 140 includes a pair of light bulbs or lamps 271 and a photocathode 273. The lamps 271 and the photocathode 273 are mounted in suitable sockets 272 secured to the front wall below the manifold assembly 212 and are disposed in horizontal alignment so that light reflected from the portion of the reflective strip 122 (FIG. 3) exposed through the bottom longitudinal slot 121 of each panel 80 will provide a signal to an appropriate control circuit. The circuit controls operation of the motor 88 and the electromagnetic brake 196 to stop upward movement of each lowermost panel in the front view portion of the path of movement of the display assembly when the panel advances into proper vertical alignment with the noules of the carriage.
introduced into the manifold housing. As the control circuit receives a digital signal from a teletype line to cause the display apparatus todisplay data, the clutch 171 (FIG. 6) is energized by the teletype signal, and the carriage will move from left to right. When the group sensor assembly 260 is brought into vertical alignment with the first column of the first group G1 of the passages, the signal produced by the photocathode tube of the group sensor assembly 260 and the lack of a signal from the photocathode tube of the column sensor assembly 250 will cause a suitable signal to be transmitted to a control circuit. This signal conditions the control circuit to permit a new character, either a number or a letter, to be formed by the balls in thefirst group G1 of passages of the column. As'the column sensor assembly 250 and the nozzles Nl-N7 move into vertical alignment with the slot S1 of group G1, the control circuit actuates selected solenoid valves to cause preselected balls in the passages of the first column of the group to be moved to the rear portions of the passages. The nozzles N 1-N7 are similarly brought into vertical alignment with the succeeding columns in the group G1 as the carriage continues it s movement, thus directing selected balls in the passages of each column to their rearward positions. As the column sensor assembly moves past the last column C5 of the first group those balls which have not been moved back will be in their front visible operative positions and will delineate a predetermined alpha-numeric character.
At the time the group. sensor assembly 260 moves into alignment with the first column of thenext group G2, it again conditions the control circuit to open selected solenoid valves as the nozzles N1-N7 move past the columns of the group G2. During the movement of the nozzles past the columns, the next character is delineated or formed by the balls of the group G2 which have not been moved back to their rear inoperative positions. When the characters of a particular line, as determined by the teletype message, have all been delineated, a suitable signal is transmitted by the control circuit to de-energized the clutch 171 and simultaneously energize the clutch 180 to cause the carriage to move from right to left, as viewed in FIG. 1, at a rapid speed. As the carriage 140 approaches its extreme left position, the electric brake 195 is energized, and the clutch is de-energized so that the carriage is heldstationaryThe motor 88 is energized and the brake 196 is de-energized at the time the carriage begins to move to the left to carry the next panel A2 of the panel assembly into the lowermost position on the front vertical portion A of the path of movement. As the slot 121 in the panel A2 moves into alignment with the panel sensor assembly 270, the assembly 270 provides a signal to the control circuit which causes the control circuit to de-energize the motor 88 and energize the brake 196.
The above sequence of operations is repeated as the panel assembly is moved sequentially as determined by the teletype signal. The information display by each panel remains in view for a considerable period of time depending on the speed of movement of the panel assembly and the number of panels within the area of the front view portion A of the path of movement. The more panels in the front view portion, the longer will be the time the information carried by each panel will be in view for a given speed of transmission of the teletype signals and the greater the amount of data that can be displayed at one time.
It will be apparent that if a line of data received from the teletype line is relatively short and the carriage is returned to its left hand position before it has moved completely across a panel, the balls in the groups of passages to the right of the