 Collimating TIR lens devices employing fluorescent light sources |
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| Lighting unit |
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| Luminaire device |
| OF PREFERRED EMBODIMENTS A multilayer luminaire device constructed in accordance with one form of ... |
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| LED with light extractor |
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| Light intensity converter |
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| Pulsed two lamp single light valve display system |
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Apparatus for controllng the opening and/or closing of high-speed shutter doors
| Details |
Inventors: Rejc, Gabriel;
Assignee: Efaflex Transport und Lagertechnik GmbH (Bruckberg-Edlkofen, DE)
Primary Examiner: Nelms; David C.
Assistant Examiner: Allen; Stephone B.
Attorney, Agent or Firm: Vigil; Thomas R.
The apparatus is utilized to detect disturbance created in an opening by objects even when the objects do not move so that they cannot be detected by a motion detector. The apparatus includes a transmitter-receiver apparatus provided at the opening comprising a plurality of arrays, each of which comprises a receiver and a plurality of transmitters. Because divergent beams are emitted by the transmitters, which preferably consist of infrared-emitting diodes, the transmitters and the associated receiver can be arranged to define a triangle in space so that the space of the opening can be completely covered by a plurality of transmitter-receiver arrays. By means of a cyclic signal sequence it is ensured that a signal which has been transmitted is checked in the receiver whether it belongs to the correct transmitter. In order to ensure that high-speed folding shutter doors which are being closed or opened will be controlled so that they move into undisturbed areas, the space in which the movement of the high-speed doors is effected must be protected so timely that an impact on an object protruding into the region of the opening will be prevented in time. For this reason an evaluation signal generated by a control circuit is utilized to operate the door drive in time. |
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DETAILED DESCRIPTION This invention relates to apparatus for controlling the opening and closing of high-speed shutter doors by detecting the presence or absence of an object in a space.
Such apparatus are constituted, e.
g.
, by photoelectric barriers, which comprise a light source as a transmitter and a photodetector as a receiver and in which the light beam is a continuous signal that is emitted by the transmitter and reaches the receiver directly or after a deflecting reflection.
Such systems comprising a transmitter and a receiver are usually described as photoelectric barriers and are relatively expensive and bulky.
A transmitter and a receiver are associated with each line to be watched.
Their large bulk is particularly due to the fact that in most photoelectric barriers the light source emits light in the visible spectral range and light which is emitted by extraneous sources also in the visible spectral range may be superposed on the light used in the barrier.
For this reason the light source must have a particularly high signal amplitude so that a superposition of light from other light sources will be avoided as far as possible.
Particularly in interior rooms, such photoelectric barrier can be more easily implemented because light, e.
g.
, from the sun, will not effect a false response of the photoelectric barrier.
Where relatively large areas must be watched, a plurality of photoelectric barriers will be required and in most cases will involve high costs of an order of many thousands of deutschmarks and will require intense maintenance.
Apparatus used outdoors or on external walls preferably comprise a detector which is responsive to ultrasonic energy or operates-like a radar.
Such detector will not be affected by disturbing light, as is the case with photoelectric detectors.
But such detectors have the disadvantage that only moving object can be detected in the area to be watched.
If an extraneous object enters into the area to be watched and said object remains in that area without moving, it will not be possible to detect whether the object which has entered is still within the area to be watched or has left that area
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Lighting 
