Lighting apparatus, in particular for stage use
The present invention relates to a lighting apparatus, in particular for stage use, and of the type described in the introductory part of claim 1.
Usually lighting apparatuses of this type for stage use are provided as spotlights, which only to a limited extent are adapted to remote control, that is that essential changes of the stage lighting - including for instance profile cutting at change of scenery - normal¬ ly require manual adjustment of several spotlights, as only remote control of colour filter is common technich.
US-A-4.890.208 discloses a ligthing apparatus for stage use comprising a lamp, which sends out a spectrum of visible and infra-red light, a reflector for projection of light from the lamp in a pencil of rays, rays of light modifying lens systems including an infra-red filter inserted between reflector and lens systems, which infra-red filter comprises a liquid chamber filled with a liquid being in a selective manner adapted to absorb infra-red light and allowing visible light to pass. The described lighting apparatus, which has a very complicated construction, furthermore comprises a diaphragm system with four knife plates being adapted to profile cutting of the rays of light, which diaphragm system may be remote controlled.
The invention has for its purpose to provide a lighting apparatus of the type mention in the introductory part, and which makes it possible in a specially simple manner to obtain any easily reproducible profile cutting of the rays of light, so that the work with the setting up of stage lighting respectively stage lighting in connection with change of scenery may be simplified.
The diaphragm system according to the invention is distinctive in that said diaphragm system for profile cutting of the rays of light comprises two or four knife plates being individually adjustable in such a manner, that the rays of light optional may be cut from several sides, and being adapted to be adjusted individually by means of moving means being adapted to be remote controlled, and that said diaphragm system in general is adapted to be turned around a center axis. By means of simple technical provisions a stage lighting, for instance a spotlight, hereby may be obtained, where the stage lighting by profile cutting of the rays of light at stage lighting respectively change of scenery may be carried out remote controlled in a reproducible manner, that is where specific profile cutting of the rays of light from the individual spotlight for the indivi-
dual scenery in a performance may be remote controlled and pre-programmed, so that the stage lighting during change of scenery may be carried out quickly and precisely.
The lighting apparatus according to the invention may be such provided, that said diaphragm system comprises two angular knife plates being individually adjustable in such a manner, that the rays of light optional may be cut from two, three or four sides.
Appropriately the lighting apparatus according to the invention may be such provided that said moving means are made of excentrically arranged steering discs, against which holding parts for said knife plates or rear edges of said knife plates are pressed by means of one or more springs, said steering discs being pivotally connected with each its motor.
And concerning a simple and precise sideways guiding of the knife plates said steering discs may advantageously be provided with a surrounding steering recess, in which said holding parts or rear edges of the knife plates are engaging.
Alternatively the diaphragm system at the lighting apparatus according to the invention may be such provided that said moving means consist of - at opposite end parts of said knife plates or holding means for said knife plates - connected pull wires being lead over warping ends of each its motor, as the knife plates are spring-affected in opposite direction.
Or the diaphragm system at the lighting apparatus according to the invention may be such provided that said moving means consist of - at opposite end parts of said knife plates or holding means for said knife plates - turnably connected spindle mechanisms being operated by also turnably arranged motors.
A further possiblity would be that said moving means consist of - at opposite end parts of said knife plates or holding means for said knife plates - turnably connected mutual parallel turning arms, of which one turning arm for each knife plate is pivotally connected with a turning motor.
In order to obtain sufficient flexibility and accuracy at the focussing of the diaphragm system at the lighting apparatus according to the invention said motors advantageously may consist of servomotors or stepmotors.
For stage lighting the lighting apparatus according to the invention with extra advantage may comprise a mirror being adapted to be tilted 80 to 90 degrees and to be rotated about 180 degrees, as the apparatus preferably is adapted to be permanently mounted in mainly horizontal position.
The invention is explained in more detail in the following with reference to the drawing, in which :-
Fig. 1 shows a principle sketch of an embodiment for a lighting apparatus according to the invention,
Fig. 2 shows a principle sketch of another embodiment for a lighting apparatus according to the invention,
Fig. 3 shows a plane view of an embodiment for a diaphragm system for a lighting apparatus according to the invention,
Fig. 4 shows in views A - C a part of another embodiment for a diaphragm system for the lighting apparatus according to the invention,
Fig. 5 shows a view corresponding to the arrangement shown in Fig. 4 A,
Fig. 6 shows a part of an alternative embodiment for a diaphragm system for the lighting apparatus according to the invention,
Fig. 7 shows a part of a further embodiment for a diaphragm system for the lighting apparatus according to the invention,
Fig. 8 shows an embodiment for a diaphragm system with two angular knife plates and three motors for a lighting apparatus according to the invention,
Fig. 9 shows a further embodiment for a diaphragm system wiϋ two angular knife plates and four motors for a lighting apparatus according to the invention,
Fig. 10 shows a still further embodiment for a diaphragm system with two angular knife plates and two motors for a lighting apparatus according to the - invention, and
Fig. 11 shows a part of a still further embodiment for a diaphragm for the lighting apparatus according the invention.
The lighting apparatus or spotlight 2 shown in the principle sketch cf. Fig. 1 comprises a light source 4 with reflector 6, a heat filter 8, a condenser lens 9, a diaphragm system 10 with belonging steering means and a lens system 12 for focussing and/or zooming of the rays of light 14, before the latter leave the spotlight 2.
The lighting apparatus 16 shown in the principle sketch cf. Fig. 2 comprises the same components as these of the spotlight cf. Fig. 1. The lighting apparatus 16 is furhermore built up as a light scanner with a mirror 18, which as indicated may tilt in relation to vertical, and which furthermore may be rotated about a horizontal axis, as the light scanner 16 is adapted to be mounted in horizontal position, so that the rays of light 20 by tilting and turning the mirror 18 may light up a very large area of for instance a stage.
The diaphragm system 10 may be built up in many different manners, where it is common that so-called knife-plates 22 are used being individually movably arranged close behind each other that the rays of light 14 or 20 effectively may be profile cutted in accordance with purpose/need, and which cf. Figs. 3 - 11 may be arranged in many different manners.
The diaphragm system 10 shown in Fig. 3 comprises four knifeplates 22 each being secured in a holding part 24 which in the transverse direction being controlled by means of a steering journal 26 engaging into a steering rail 28 or eventually only in a corresponding recess provided in a circular supporting plate 30. At opposite end parts of the holding parts 24 these rest against excentrically arranged steering discs 32, which along the periphery in a not shown manner are provided with a steering recess, in which said holding parts 24 are steered. Furthermore the holding parts 24 are spring- affected against the steering discs 32 by means of pulling springs 34 being secured in a distance from the holding parts 24 to the supporting plate 30 and 36.
The steering discs 32 are pivotally connected with each its motor being placed on opposite side of the supporting plate 30 and secured thereto. Furthermore the support- ing plate 30 is adapted to be rotated in relation to a building-in plate 38, as the suppor¬ ting plate 30 is pivotally arranged by means of three steering rolls 40. The supporting plate 30 is furthermore provided with an arched or edged rack 42, which for rotation of
the supporting plate 30 through about 45 degrees engages with a gear wheel being drive-connected with a drive motor on opposite side of the building-in plate 38.
The knife plates 22 or the holding parts 24 are kept in their places close to each other 5 by means of suitable slideways. The knife plates 22, which preferable are replaceable, consist of plate material, which may stand heigh temperature, for instance incoloy, aluminium or a corresponding heat-resistant plate material. The holding parts 24 consist of a heat-resistant, self-greasing material, for instance teflon or a teflon-coated material. Possibly the holding parts 24 do not exist, as the rear edges of the knife plates 10 22 itselves may be adapted to engage directly with the steering means - steering discs or steering motors.
The focussing arrangement shown in Figs. 4 A - 4 C uses turnably arranged motors 46, which by means of each its spindle mechanism 48 also in a turnable manner are
15 connected with knife plates 50, so that said knife plates individually from each its side may be moved into the rays of light represented by the dotted circle 52. It shall be pointed out, that only the knife plates 50 and the motors 46 is shown in only one plan, that is that the arrangement furthermore comprises 4 motors 46 with each its spindle mechanism 48 for further two knife plates 50. As it appears from the shown arrange-
20 ment a quite arbitrary profile cutting of the rays of light 52 may be obtained, as the shown arrangement in general furthermore may be rotated.
The arrangement shown in Fig. 6 comprises for each of two knife plates 50 one turnably arranged motor 54 and to mutual parallel turning arms 56, of which the one
25 turning arm extents between one end of the knife plate 50 and the motor 54, while the other turning arm 56 is passive, as it extents between the opposite end of the knife plate 50 and a fixed turning point being placed in a position corresponding to the turning motor 54. Also here it applies that only the one plan of the focussing arrangement is shown, that is that perpendicular to the shown arrangement a corresponding arrange-
30 ment with to co-operative knife plates 50 is arranged.
Fig. 7 shows how the knife plates in stead of displacement into the rays of light during profile cutting may be swung inwards. The shown system comprises four turnable knife plates on each its motor, which preferably consists of a servo motor or a step motor, 35 which in general is the case in connection with the invention.
Fig. 8 show how the profile cutting of the rays of light may be carried out by means of two mutual cooperative and mutual displaceable arranged angular knife plates 58 and
60 being operated by respectively one and two motors, that is totally by three motors. Furthermore the system comprises a fourth motor for rotation of the system - as a unit.
Fig. 9 shows profile cutting by means of two angular knife plates each being operated by two motors, that is that the system comprises a total number of five motors; while the arrangement for profile cutting shown in Fig. 10 comprises two angular knife plates being operated by each its own motor.
Finally Fig. 11 shows an arrangement, where the knife plates are operated by pull- wires, pressure springs and two motors with wiredrums for each knife plate.