US 3509509 A
Description (OCR text may contain errors)
April 28, 1970 A. r-ZfRAPISARDA APPARATUS FOR PROVIDING A PLURALITY 0F INDEPENDENT CONTROL SIGNALS 4 vShe:ets-Sheet 1 IJ ommolvyvml @1L I J www# J 1J www w,-
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I 1 l l r l l IFI lllllllllmll l 1W L I V Mnpgllmllllmll J W I l IHIIHHHWHH o l l l I I I 64 69 1 "/IHIIIIH" L ,I INVENTOR. N1'- ALEX/w05? F www April 28, 19470 A. F. RAPlsARDA APPARATUS FOR PROVIDING A PLURALITY OF INDEPENDENT CONTROL sIGNALs v 4 Sheets-Sheet 2 Filed Dec- 5. 1967 April 28, 1970 A. F. RAPlsARDA 3,509,509
APPARATUS FOR PROVIDING A PLURALITY OF INDEPENDENT CONTROL SIGNALS Filed DSC. 5. 1967 4 Sheets-Sheet 5 April 28, 1970 A. F. RAPISARDA 3,509,509
APPARATUS FOR PROVIDING A PLURALITY 0F INDEPENDENT CONTROL SIGNALS Filed Dec. 5. .1.967v 4 Sheets-Sheet 4 United States Patent O 3,509,509 APPARATUS FOR PROVIDING A PLURALITY OF INDEPENDENT CONTROL SIGNALS Alexander F. Rapisarda, Mount Vernon, N.Y., assignor to Ward Leonard Electric Co., Mount Vernon, N.Y., a corporation of New York Filed Dec. 5, 1967, Ser. No. 688,158 Int. Cl. H01c 5/02 U.S. Cl. 338-128 2 Claims ABSTRACT OF THE DISCLOSURE A preset card comprises a mounting board and cover. The mounting board has spaced parallel potentiometers extending between electrically conductive buses at adjacent opposite edges of the mounting board. The potentiometers have movable contacts mounted on the cover for tapping a given voltage. The potentiometers comprise a wire wound resistor extending between the buses and electrically connected thereto and rails parallel to the resistors and connected to the resistors by the movable contacts. The rails project through the mounting board for contacting the terminals of a controlled apparatus. The preset card is removably mounted in a panel having individual terminals for engaging a respective rail for applying the selected voltage to a controlled apparatus.
BACKGROUND OF THE INVENTION In present commercial systems for dimming theatre lights a preset console is provided with two or more potentiometers for a given lighting circuit. One set of potentiometers is set in advance of the scene and the lighting systems faded from the controlling set to the succeeding controlling set on a change of scenes. This means that the operator of the stage lights is required to set each scene for each performance. This has the disadvantage of error being introduced into the presetting of the Vpotentiometers so that the planned or programmed lighting effect is not attained due to a misadjustment of the potentiometers.
SUMMARY OF THE INVENTION An apparatus for providing a plurality of independent control signals, such as a preset card for setting the illumination of stage lights, comprises a mounting board with potentiometers on one side and the terminals for the control signals on the opposite side and a cover with movable contacts engaging a respective potentiometer for selecting the control signals appearing on the terminals on the other side. The apparatus or preset card is mountable in a console panel for insertion and removal therefrom with the movable contacts preset to provide the selected signals. v
An object of the invention is to provide a preset signal control apparatus that is readily inserted and removed from a panel for applying signals at preset values to controlled equipment.
Another object of the invention is to provide a preset signal control apparatus that comprises a minimum or parts and is easily assembled.
Other and further objects and advantages will be apparent from the following description taken in connection with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is a front view of the preset card mounted in a panel.
FIG. 2 is a partial side view of the preset card mounted in a panel and partial sectional view taken along lines 2 2 of FIG. 1.
FIG. 3 is a sectional view of the preset card mounted in a panel taken along lines 3-3 of FIG. 1.
FIG. 4 is a perspective view of the cover and mounting board exploded from the panel shown perspectively.
FIG. 5 is a front view of the mounting board.
FIG. 6 is a fragmentary perspective view of the mounting board with a rail illustratively positioned forwardly from the mounting board.
FIG. 7 is an enlarged perspective fragmentary view of the cover with a movable contact separated from the cover. Y
FIG. 8 is an enlarged perspective view of the contact and supporting block of the movable contact in a separated relation.
FIG. 9 is a fragmentary perspective rear view of the comer of the cover.
FIG. 10 is a sectional view of the mounting board taken along lines 10-10 of FIG. 5.
FIG. 11 is a sectional view of a resistor of the potentiometer taken along lines 11-11 of FIG. 10.
FIG. 12 is a front view of the terminal board.
DETAILED DESCRIPTION As best shown in FIGS. 2, 3 and 4 the preset card comprises a mounting board 20 and a cover 21, both made of a plastic electrical insulating material. The mounting board has buses or electrically conductive strips 22, 23 extending longitudinally along opposite edges of the mounting board on the same side. Potcntiometers 24 are mounted between the buses 22, 23 in a parallel relation. The cover 21 is positioned over the resistors 36 and rails 40 of the potentiometers and the movable contacts 25 (FIGS. 2 and 3) of the potentiometers are slideably mounted in the cover and adjustably engage the resistors 36 and rails 40 of the potentiometers. The mounting board and cover are fastened together providing a unitary member that is mountable in a pan assembly 26 rernovably holding the preset card. The pan assembly 26 1s secured to a panel 27. The pan assembly has a terminal board 28 (FIG. 3) with resilient contact fingers 29 for engaging the rails 40 of the potentiometers 24 (FIG. 3) to receive the selected voltage or signal and pass it to the controlled equipment (not shown) through the terminal extensions 30 (FIG. 3) of control lingers 29. The terminal extensions 30 are connected to controlled equipment such as theatre dimmers.
The mounting board is formed from a thin plastic sheet of insulating material and has a generally elongated rectangular shape, as shown in FIGS. 4, 5 and 6. The buses 22 and 23 are formed from electrically conductive strips riveted to the mounting board at spaced points 33 and electrically isolated from one another. Lugs 34 and 35 are stamped from the respective buses 22, 23 into U-shaped clamps for receiving the wire wound resistors 36 spanning the space between the buses. The wire wound resistors 36 (FIG. l1) comprise a solid copper core 37 witha polyethylene coating 38 electrically isolating the helically wound resistor wire 39 from the conductive core 37. The resistors are preferably spot welded and/ or cemented with a conductive cement to the lugs 34, 35 to electrically connect the resistors to the buses 22 and 23. The resistors 36 are mechanically secured to the buses by slight closure of the U-shaped clamps. The wire 39 is of a fine gage and closely wound to evenly divide a 24volt supply connected to the buses 22, 23. The resistors are spaced parallel to one another with the rails 40 positioned adjacent a respective resistor and presenting an upper at edge 41 for receiving the tapped voltage. The movable contacts 25 bridge the resistors and rails and reect a potential proportional to the position of the movable contacts. The rails are stamped from brass or copper strip and extend parallel to the resistors and have a generally rectangular cross section. The lingers 42 extend over or in front of the bus 22 and are spaced therefrom. However, a thin insulating strip 31 may be provided on the front of bus 22 to insure that no contact is made between the bus 22 and lingers 42. An insulating strip 32 may be provided on the front of bus 23. At the bus 22 end projections 43 are provided litting into slots 44 (FIGS. 3 and 6) in the mountingjb'oard. At the other end of the rails L-shaped projections 45 extend in the plane of the rail and ft through slots 46 (FIGS. 3 and 6) in the mounting board so that the L-shaped projections extend underneath the board on the opposite side from the bus 23 to electrically isolate the rails 40 from the bus 23. The rails 40 are easily positioned on the mounting board by inserting the L-shaped projections 45 through the slots 46 and pivoting the rails 40 into place with the projection 43 extending through the opening 44.
At one end of the mounting board the bus 23 is provided with a T-shaped terminal 47 (FIGS. 2, 4, 5 and 6) extending through the mounting board and electrically fastened to the end of the terminal to provide a contacting surface 48 (FIG. 2) underneath the board for engaging a voltage source. At the other end of the board a terminal 49 (FIG. 5), similar in configuration to the rail 40, has an L-shaped projection 50 extending through a slot 51 for engaging the other terminal of the power source. The terminal 49 is connected to the upper bus 22 thereby permitting the energization of the resistors 36.
The cover 21 is a molded pl'asticfmember and has a front panel member 55, longitudinal sides 56 and 57 and ends 58, 59 perpendicular to the panel member 55. The sides 56 and 57 (FIG. 3) and ends 58 and 59 (FIG. 2) have a recess 60 (FIGS. 2, 3 and 9) formed therein to receive the mountingboard 20. Notches 61 are provided in the side 56 to receive the fingers 42 of the rails 40. Parallel partitions 62 extend between the sides 56 and 57 to form recesses or grooves 63 (FIG. 9). The partitions extend from the panel member 55 down to the mounting board 20. Slots 64 (FIGS. 1 and 11) extending parallel to the resistors 36, rails 40 and -grooves 63 are provided in the panel member 55. The movable sliderl contacts 25 extend through the slots 64 and are slideably mounted on the panel member 55.
The movable slider contact 25 (FIGS. 2, 3, 7 and 8) comprises a supporting block 65 with an indexing projection 66 and a positioning projection 67. The supporting block has a rectangular configuration with the projections 66 and 67 extending therefrom, as illustrated in the drawings. A bolt or threaded member l68 extends through the threaded positioning projection 67 to receive a knob 69. rI`=he projections 66 and 67 fit in the slot 64 with the supporting block 65 in the groove 63 (FIG. 2)..The bolt 68 extends exteriorly to the panel member 55 so that the knob 69 is on top of the cover 21 readily accessible for setting the position of the movable contact and locking it in place by threading down against the top surface of the panel member 55. A generally U-shaped, bifurcated beryllium-copper contact member 70 .has one leg separated into fingers 71 and 72 (FIGS. 7 and 8) for lengaging the rail 40 and resistor 36, respectively. The supporting block 65 is guided in its longitudinal movement by the projections 66 and 67 so that the movable contacts linearly move in relation to the resistor 36 and the rail 40. The rounded portions 71a and 72a engage the rail 40 and resistor 36 and when the movable slider contact 25 is at the low voltage end the rounded portions 71a and 72a may be spaced from the end of the resistor in order to provide a minimum voltage for application to the controlled equipment.
The cover has bosses 73 (FIGS. 1 and 9) for receiving screws 74 passing through holes and/or slots 75 (FIGS. 5 and 6) in the mounting board 20 to securely clamp the mounting board and cover together. The slots 61 receive the fingers 42 of the rails to limit the sidewise movement of the rails and hold the surface 41 facing the finger 71.
The preset card tits into the pan assembly 26 (FIGS. 2, 3 and 4) having a bottom 76, three side walls 77 perpendicular to the bottom 76 and flanges 7S extending perpendicular to the side walls to-overlap with the panel 27. The pan is secured to the panel 27 by fastening means passing through the anges 78.
Along one longitudinal edge of the pan assembly 26 the side wall 77 and the flange 78 are omitted and the bottom wall 76 is cut away, as illustrated in FIGS. 3 and 4, to form a longitudinal opening 80 between the bottom wall 76 and the panel 27. The longitudinal projection 81 (FIGS. 1, 3 and 4) on the side 57 ts underneath the panel 27 to rotate the preset card into the pan assembly. On the side 56 the longitudinal projection 82 (FIGS. 3; 4, 7 and 9) engages the projections 83 (FIGS. 1, 3 and 4) mounted on the leaf spring 84 attached to the longitudinal side 77 to retain the preset card in the pan assembly until forcefully removed therefrom.
Underneath and attached to the pan assembly 26 is the terminal board 28. The electrically conductive fingers 29 are riveted to an insulated block or strip (FIGS. 2, 3 and 12). Bolts 86 passing through the strip 85 are fastened to` mounting members 87 on the bottom 76 lof the pan. The fingers 29 have V-shaped portions 291i extending into the slot 80 to engage the L-shaped portions 45 of the rails 40 (FIG. 3). Thus each potentiometer 24 may be connected to a respective controlled circuit.
The opening 80 is partially closed over by a longitudinally extending insulating strip 88 (FIGS. 3 and 4) riveted to the bottom 76 to prevent shortng of the rails 40' on insertion of the preset card in the panel.
It is thus seen from the foregoing that a preset card has been described which is rugged in construction and can stand abuse while providing a range 'of controlled voltages or signals which may be readily varied by small amounts so as to easily provide the desired illumination for stage lights. The setting of the movable contacts at the desired controlled voltage is readily attained by loosening the knob `69, adjusting the movable contact 25 and relooking in the new position by tightening the knob 69. The parts are readily made by standard techniques and are easily fitted together to form the assembled preset card. The partitions in addition to separating the potentiometers also engage the exterior surface of the mounting board to add rigidity and strength. l
Various modifications and changes may be made in the foregoing preset card without departing from the invention as set forth in the appended claims.
1. A preset card for providing a plurality of inde-I pendent control signals and for being removably mounted in a pan assembly comprising a mounting board, a cover, said cover having a plurality of partitions forming a plurality of grooves, slots in said cover-between said partitions and extending longitudinally thereto, two buses on said mounting board extending parallel to one another in spaced relation and crosswise to said partitions, wound potentiometers on said mounting board extending between said buses and between said partitions to fit in said grooves, said cover slida'bly supporting movable contacts fitting in said grooves to engage 4respective potentiometers, means exterior to said cover mounted on the movable contacts for positioning and securing said movable contacts to provide selected control signals, said potentiometers comprising resistors connected across said buses and elongated rails on the same side of said mounting board as said resistor and extending longitudinally adjacent to said resistor with said respective movable contacts having resilient fingers slidably engaging said resistors and rails, said rails having portions extending rearwardly to the opposite side of said mounting board for removably engaging terminals connected to a control circuit in said pan assembly, means on said card for releasably engaging the pan assembly, said slots extending parallel to said potentiometers and said partitions and said movable contacts having supporting blocks fitting in said grooves and having projections extending from said supporting block into said slots for guiding said blocks in linear movement in said grooves, said ngers being mounted on said block for electrically connecting said rail and said resistor, fastening means on said block extending exterior to said cover, and a knob mounted on said fastening means for moving said movable contact and securing said contact in a given position.
2. The apparatus as set forth in claim 1 wherein each of said rails has a inger and said cover has notches for receiving a respective finger to hold said rails in engageable relation with said movable contacts.
References Cited UNlTED STATES PATENTS 2,288,043 6`/l942 Stanton '338-183 2,339,721 1/1944 Wilson 338-183 2,975,389 3/1961 Karg 338-183 3,307,133 2/1967 Wolff 338-183 3,341,799 9/1967 Van Benthusyen et al. 338-184 3,390,366 6/1968 Izenour 338-130 3,416,120 12/1968 Klug et al 338-183 LEWIS H. MYERS, Primary Examiner G. P. TOLIN, Assistant Examiner U.S. Cl. X.R. 338-183, 194