Abstract: An optical web monitoring apparatus has an illuminating arrangement which images the pupil of the source of illumination into the observing pupil of the camera objective (18) of a diode row camera using a strip-like concave mirror (14), or two strip-like concave mirrors (14, 15), and thus achieves the maximum attainable light yield. The construction is realized such that a fault seeking apparatus with a laser scanner can be used at the same time using the same mirror strips (14, 15). Thus two monitoring operations can be carried out simultaneously.

Abstract: In a method of marking faults on rapidly moving material webs the material web is moved past a fault detection scanning device, which cyclically scans the web transverse to its longitudinal direction, and past a marking device at a defined distance therefrom. Signals coming from the fault detection scanning device (16) are analyzed one after the other to determine whether they are fault signals or structure signals. The fault signals which are detected are stored with their web coordinates. Checks are made at short time intervals as to whether a fault signal is present in the store (11) which corresponds to the longitudinal coordinate which is just moving past the marking device (13). A marking is effected if a fault signal is present at the corresponding web coordinates (FIG. 1).

Abstract: An apparatus for measuring the transit time of electromagnetic waves has a pulse generator (11) which is arranged in a feedback loop (12) and which can be triggered by pulses. Either the measurement path (13) or a reference path (14) with a reference receiver (16) at the end of it can be selectively included in the feedback loop (12). The pulse generator is also connected to a computing/counting stage (19) which counts the pulse transmitted during the measurement and reference periods separately and computes the transit time therefrom (FIG. 1).

Abstract: The luminescence sensor has a housing insert (30) which is formed as an extruded section which carries the optical and optoelectronic components in a preadjusted arrangement. The housing insert can be built into the housing (10) on which a peripheral part of the optical system is mounted in an adjusted manner. A fluorescent tube (34) with a precision mount is located in a receiving mount of the housing insert (30) and is accessible in order to exchange it through a housing opening (56).

Abstract: In a machine having automatic article transport individual identical articles are conveyed along a conveyor path (21) past various processing stations. A clock (12) is associated with the conveyor path. Furthermore, a characteristic detection apparatus (13) is provided which delivers information corresponding to the characteristics of the articles (16) which are moving past to a characteristic shift register (11), which is pulsed by the clock (1). An article sorting apparatus (14) is arranged spaced from the characteristic detection apparatus and is controlled by the associated storage (11') of the characteristic shift register. A further presence shift register (15) is arranged parallel to the characteristic shift register (11) and the information contained in the presence shift register (15) is compared with the output of a presence detection apparatus (17) and can be used to stop the machine in the event that a deviation is detected (FIG. 1).

Abstract: A light scanning device for determining the condition of a surface has an optical system which concentrates light beams leaving a scanning line in a specific direction at a concentration zone (16'). A light concentrator (11) with a light entry surface (12) and a desired light exit surface (13) arranged parallel thereto are arranged at the location of the concentration zone (16'). Convexly curved side surfaces (15) which are mirrored at the outside are present between the light entry surface (12) and the desired light exit surface (13) and ensure that light entering alongside a dark field stop (14) all falls onto a photomultiplier which adjoins the desired light exit surface (13) (FIG. 5).

Abstract: An optical thread breakage monitoring apparatus for tufting machines has a laser beam scanning apparatus (21). The retroreflecting strip (11) illuminated by this laser beam scanning apparatus (21) is secured above the eyes (12) of the needles (13) to the front side of the needle beam (14) (FIG. 1).

Abstract: An optoelectric comparison apparatus for structures on plane surfaces or for planar structures has a laser light source 35 the operational light beam of which is split into two component beams 21, 22 by an optical displacement device 26, 25 for laterally displacing part of a beam. These two component light beams 21, 22 impinge on the mirror surfaces of a mirror wheel 11 obliquely to the axis of rotation 20. Two mutually crossed flat first strip mirrors 12, 13 are arranged in the direction of the light reflected from the mirror wheel 11 and each receive only one of the emergent component light beams 14, 15. The emergent component light beams 14, 15 are deflected in substantially opposite directions where, in each case, a further plane second strip mirror 16, 17 is provided which reflects the light to the scanning surface parallel to the light beams 14, 15 which enter into the first strip mirrors 12, 13.

Abstract: An optical fault seeking apparatus has a light scanning apparatus (21) and a light line receiving apparatus (14) which receive the light reflected from the material to be investigated and direct it onto a photoelectric converter. The light beam which forms the light line 11 impinges at an acute angle (.alpha.) onto the surface (13) of the article or web (18) under investigation. The image forming optical light line receiving apparatus (14), effectively consists of two light receivers (14, 14') positioned away from the normally reflected beam (23) and arranged to receive light from respective ones of two spaced apart strip-like regions (11', 11") extending parallel to and partly overlapping the line of light (11). In this way the device is able to detect faults (e.g. lumps or depressions) in fleece-type webs with irregular surface structures which are normally very difficult to monitor with optical fault seeking apparatus (FIG. 1).

Abstract: A protective zone apparatus on a vehicle capable of travelling along a path has a light transmitter (16) and a light receiver (18). The transmitted light beam (11) is obliquely directed onto the path of travel (12) at a first fixed angle (.alpha.) and executes a scanning movement about an axis (13) perpendicular to the path of travel (12). The received light beam extends at a second fixed angle (.beta.) from the point of impingement (15) of the transmitted light beam (11) on the path of travel (12) to the perpendicular axis (13) and executes a scanning movement synchronous with that of the transmitted light beam (11). An electronic processing circuit transmits a control signal which stops the vehicle if an obstacle arises in the protective zone (FIG. 1).

Abstract: An elongate retroreflector has a cylindrical lens arrangement (11) and a cylindrical stepped mirror arrangement arranged therebehind, with the axis (M) of the cylindrical stepped mirror arrangement extending parallel to the axis of the cylindrical lens arrangement (11) and lying on the principal plane (H) of the cylindrical lens arrangement, whereas the focal line (f) of the cylindrical lens arrangement (11) is arranged on the stepped mirror arrangement (12).

Abstract: An apparatus for determining the transit time of ultrasonic pulses in a fluid has two spaced apart electro-acoustic converters (11, 20). A transmitter signal proportional to the sound pressure is applied via a controllable delay circuit (23) to a multiplication circuit (25) to which the received signal is also passed. The product signal is in turn passed to a transit time detector circuit (10) (FIG. 1).

Abstract: A fault detecting apparatus for flat articles generates a line of light on the article which is imaged onto a photoreceiver via an optical system having cylindrical imaging characteristics. For use with an article 11 having light diffracting characteristics the line of light 12 is arranged substantially at right angles to the structure 13 which causes the light diffraction. The optical system 14 having cylindrical imaging characteristics detects, apart from the zero order at least also the first diffraction order of the light leaving the article. The light of the first diffraction order is also imaged onto its own photoreceiver (FIG. 1).

Abstract: An optical thread breakage monitoring apparatus for tufting machines contains a laser (36), a mirror wheel (17) which is illuminated by the laser and also a plurality of spaced apart strip-like deflecting mirrors (23, 11, 12) which direct the laser light which is cyclically deflected by the mirror wheel (17) onto a horizontally disposed concave mirror (13) which is arranged above the mirror wheel (17) and the deflecting mirrors (11, 12) and which forms the scanning beam (20'") which is directed towards the row of needles (14) of the tufting machine. A retroreflecting strip (15) is arranged behind the row of needles (14). The receipt of the light reflected from the retroreflecting strip (15) takes place in autocollimation (FIG. 1).

Abstract: In a light barrier apparatus for monitoring doorways to the left and to the right of a central post two light transmitter/receiver devices (11, 12) are mounted together with the associated electronic circuitry on a structural element to form a first unit. This unit is releasably secured to a base member which carries two deflecting mirrors (14, 15) and the electrical connection terminals. The unit can be removed from the base member (17) at right angles to a plane which includes the optical axes (11c, 12c) of the light transmitter/receiver devices (11, 12).

Abstract: In optical mark recognition apparatus the light transmitter has two light sources 11, 12 which can be selectively switched on and which transmit light beams of different spectral compositions. A semi-permeable mirror 15 directs the light beams 13, 14 of both light sources 11, 12 along a common optical path 16 (FIG. 1).

Abstract: In an optical fault seeking apparatus for webs moved in their longitudinal direction there is provided an optical scanning arrangement which generates a light bead on the surface of the web which moves transversely to the direction of the movement of the web. The scanning arrangement generates several light traces (12, 13, 14) which are displaced in the direction of advance and are parallel to one another. A light receiving arrangement (15) for each light trace has a photoelectric receiver (16, 19; 17, 20; 18, 21). The light traces (12, 13, 14) either adjoin one another or have a distance such that after the passage of the web (22) past all the light traces (12, 13, 14) each web region has been detected once by one scanning light bead (FIG. 1).

Abstract: An apparatus for determining the transit times of ultrasonic pulses in a fluid has at least two electroacoustic converters (11, 20) arranged spaced apart in the fluid. An electrical signal proportional to the sound pressure generated at the transmitting converter (11) is derived from the transmitting converter (11) and is fed to the input of a correlation circuit (12).

Abstract: A fault pre-warning device for use in tufting machines has a switching strip (11) over which the carpet web is guided in such a way that the switching strip (11) is acted on by a defined force in the switching direction. On the occurrence of excessive tension in one or more of the warp threads the switching strip (11) initiates a switching process.

Abstract: Light barrier apparatus arranged in a housing comprises at least one photoelectric converter, at least one front lens arranged in a wall of the housing, an electronic circuit connected to the photoelectronic converter(s), power supply lines leading from power supply terminals to the electronic circuit, and also, in the case of a receiver or a transmitter/receiver signal lines and signal terminals. The housing is subdivided into first and second housing parts (11, 12) which are pivotably connected together by an articulated coupling (15). The first housing part (11) contains, at least in large part, the electronic circuit including the power supply lines, power supply terminals and, if present, the signal lines and signal terminals. The second housing part contains at most a part of the electronic circuit, the electronic converter and also the front lens.