Abstract: A method and a device for controlling a drive unit which conveys a striplike laterally pre-printed recording medium, whereby a sensor is sensitized with respect to a regularly re-occurring mark of the recording medium. The recording medium is continuously scanned by the sensor during the printing operation and the speed at which the recording medium is conveyed is adjusted according to scanned signals from the sensor.

Abstract: Apparatus and method for manufacturing helically wound insulated conductors with filament fillers includes first and second payoff stations for paying off a plurality of insulated conductors and elongate filaments of filler materials. These cable components are guided from the payoff stations to a closing die, and are arranged in positions suitable for twisting into a cable by a double twist machine to form a cable of twisted insulated components forming radially outwardly facing helical interstices each of which is substantially filled with another one of the filaments of filler material. Differential or incremental lengths of filler material are metered upstream of the double twist machine to compensate for the differences in the radial distances of the insulated conductors and filaments of filler material on the center or cable of the axis.

Abstract: A method of controlling the drive of the electric pretensioning unit of rotary printing machines having individually driven rotary printing cylinders and folders is specified, so that, in the event of changes being made to the paper grade or to the production sequence without the machine being stopped, only slight web tension changes occur, and the operating limits with regard to web tension are reliably maintained. This method is equally well suited to rotary printing machines having individually driven printing units or printing bridges and folders and to conventional printing machines that are driven by mechanical shafts via couplings.

Abstract: Drag rollers disposed in a region from the paper feed side to the paper discharge side of a printing machine are driven one after another from the paper feed side with torque control, by which the slack of a web is removed successively from the upstream side of a web delivery running path.

Abstract: A method for self-adjusting color and cut register control in rotary printing machines having individual or a plurality of webs is specified, according to which the amount of relative web stretching of the individual web sections is calculated from the operating points of the drives driving the web and the correcting variables for color and cut registers are derived from the production-dependent combination of all the stretching values.

Abstract: A film conveying apparatus includes a conveying mechanism and a speed control mechanism. The conveying mechanism includes a plurality of lower rollers arranged in a lateral direction perpendicular to a film conveyed direction. The lower roller is equipped with a motor to variably control its speed. A plurality of upper rollers is disposed to correspond to the lower rollers so as to sandwich the continuous film with the lower rollers. The roller-speed control mechanism controls a rotation speed of each lower roller so that the film is conveyed at a desired speed in a desired direction.

Abstract: In the production of thin film that is extruded onto a cooling roller and then fed through a further treatment station such as stretching roller station, it may become necessary to stop the extrusion if a fault is present in the further treatment station. In order to avoid stopping the extrusion, a detour station with a roller set is positioned between the extrusion station and the further treatment station for detouring extruded film in response to a detected fault in any system component, except the extruder, whereby the extrusion can continue while the film is supplied to some other use while its supply to the further treatment station is interrupted. The detouring roller set includes at least one guide roller and a press-on roller that is automatically movable, for example by a piston cylinder device into a working position in response to a fault signal.

Abstract: An apparatus is provided in a printer to prevent wrapping of the paper web onto the printer's fixing roller which fixes the toner particles onto the paper web. The apparatus includes a sensor to monitor the speed and moving direction of the web at the output of the fixing station. The sensor is connected to a controller which operates to halt the operation of the fixing station or the printer when the sensor senses a reversal of the moving direction of the web. The controller may average the web moving speed and compare the average speed to a predetermined speed for halting printer operation if the average speed traverses the predetermined speed.

Abstract: A metal coil printing mechanism for providing alignment between two patterns to be printed on a surface of the coil includes a blanket cylinder for applying a pattern to the metal coil and first and second plate cylinders which apply first and second patterns to the blanket cylinder. The first plate cylinder is geared directly to the blanket cylinder for rotation therewith. The second plate cylinder is geared for rotation with the blanket cylinder through a phase shifting device. The phase shifting device can be adjusted such that the circumferential position of the second pattern relative to the first pattern is adjusted such that desired alignment of the two patterns can be obtained.

Abstract: Press rollers for being pressed respectively against wires are provided on an upper side of the wires while length-measuring rollers for respectively contacting the wires are provided on a lower side of the wires. A number of revolutions of each length-measuring roller is detected by an encoder, and an amount of actual feed of each wire is detected in accordance with its revolution number, and a pulse signal, representing its detection value, is sent to a comparison processing portion of a controller. In this comparison processing portion, the amount of actual feed of each wire, detected by the encoder, is compared with a predetermined feed amount of a feed roller beforehand given as an instruction to the processing portion, and if there is any difference between the two, an instruction is given to a servo amplifier, and the servo amplifier sends an instruction to a servo motor for driving the feed roller so as to rotate the servo motor in a normal or a reverse direction in accordance with this difference.

Abstract: A primary drive assembly which drives photosensitive material through a photographic processor is provided at a point of a photoprocessing path of the processor at which a precise speed control is desired. A secondary drive assembly is provided downstream of the primary drive assembly at the end of the processor to pull the photosensitive material through the end of the processor. The primary drive assembly includes a control member which controls the speed of the secondary drive assembly based on the tension of the photosensitive material in the vicinity of the primary drive assembly. If the tension is below a predetermined point, the speed of the secondary drive assembly is increased, and if the tension is too high, the speed of the secondary drive assembly is decreased. The primary drive assembly uses a pivotable roller arrangement in combination with a switch to monitor tension and supply a signal to the secondary drive assembly.

Abstract: A system and method for incorporating, in the production of a continuous stream of images, by an image transfer device upon a moving web, post-production operations upon the web at various locations. Locations of a web, having a plurality of images placed thereon, output from an image transfer device are tracked. Specific operations at various locations upon the web are performed by a post-production device as the web passes through it. The web is directed from the image transfer device to the post-production device. In response to the tracking of locations upon the web, the point when a location has entered the post-production device is determined. In response to this determination, the post-production device is commanded to perform its specific operation at a connect location.

Abstract: A printer includes a tractor unit for feeding continuous form paper, encoders driven in synchronization with a tractor belt, and detecting sensors for detecting rotation of the encoders to generate feed pulses at a standard interval. The printer further includes a paper top sensor which detects a leading edge of the continuous form paper to generate a paper top signal and is arranged to control the feeding of the paper based on a feed pulse generated after the paper top signal. In order to compensate for a delay of the paper top signal, the printer controller is arranged to determine if there is a delay in the paper top signal by comparing the time interval between the paper top signal and the feed pulse with a threshold value. The printer is so arranged that the threshold value is stored in a non-volatile memory and can be set after assembly of the printer.

Abstract: A sheet feeder feeds a continuous form in a reverse feeding direction to the normal feeding direction from a position detected by a first sheet sensor. A timer counts a predetermined interval until the continuous form is surely fed by the distance from the sensor to the exterior of the printer. An additional sensor, downstream of the first sheet sensor and close to the sheet outlet in the normal printing direction, is used with the timer and appropriate counting intervals to detect paper jams as the reversely fed continuous form passes through the printer. A controller stops the reverse feeding upon the detection of a jam, and displays a jam error message on a display provided to a control panel. The sheet feeder is alternatively a pair of rollers or a tractor unit.

Abstract: Apparatus and method for feeding a web having two portions in a path of travel. The apparatus comprises a first module including a device for feeding the two web portions in side-by-side relationship and a second module located downstream in the path of travel from the first module where the second module includes a device for feeding the two web portions in upper-lower relationship. Accordingly, the two web portions each form a loop between the first module and the second module so as to reorient from side-by-side to upper-lower relationship. The apparatus further comprises a controller operatively connected to the first module feed a device and the second module feed a device for setting the feed speed of the first module feed a device corresponding to the feed speed of the second module feed device. The method includes the steps of: (a) determining the feed speed of the second module; and (b) setting the feed speed of the first module to a corresponding value for a given feed speed of the second module.

Abstract: In the fixing station, the recording substrate 4 is transported by friction between two rollers (1, 2). In order to tauten the recording substrate (4), it is braked by a braking device (3) upstream of the rollers (1, 2). A length equalizing element (5) equalizes any length differences occurring in the recording substrate (4). The rotational speed of the rollers (1, 2) is controlled as a function of the deflection of the length equalizing element (5). The deflection time (txy) between reaching a deflection point a and a deflection point b is registered and compared with a desired deflection time (tsp). The braking force of the braking device (3) is reduced if the desired deflection time (tsp) is exceeded.

Abstract: A continuous form printer is provided with two rotary encoders, corresponding to different paper feed intervals, and mounted coaxially on a drive shaft. The drive shaft drives a tractor for feeding the paper. The rotary encoders are read by photo-interruptor sensors, and the sensor signals are selected by a selector. The selector is able to select either one of the sensor signals generated by the encoders, or a signal formed by performing an AND operation on the two sensor signals. A controller controls a motor driving the drive shaft according to the selected signal, the selected signal corresponding to a chosen feeding interval. The controller is further able to precisely adjust the leading edge of the paper to a predetermined position based on the selected sensor signal, a known paper length, and a paper top sensor.

Abstract: Apparatus for feeding flexible sheet (2) onto an inwardly facing curved surface (6) of an imagesetter comprises a feed system (3,4,7,8) for feeding the sheet from an input side onto and along the surface towards an output side. The feed system is also adapted to exert a force in the plane of the sheet (2) to cause the sheet to flex into conformity with the surface (6) and to form a ridge near one side. A monitoring system (12) monitors for formation of the ridge as an indication that the sheet conforms to the curved surface.

Abstract: A quilting machine includes a multiple needle quilter with a panel cutter located in-line therewith and downstream thereof and having an accumulator therebetween. A programmable controller operates the quilter to stitch a programmed series of one or more patterns on a web. A feed roller angular encoder measures the quilted web length fed under tension to the accumulator. A detector signals when the accumulator is full, whereupon the controller causes web to be fed from the accumulator to the panel cutter, where it passes without tension thereon toward a photo sensor. The photo sensor signals the controller which activates the cutter to sever a predetermined panel length from the web. The controller then reads information from the encoder and the accumulator detector to determine the amount of stressed quilt required to replenish the cutoff panel length.

Abstract: A feed monitor for providing a selectable midcycle coil stock feed check on a mechanical power press. A midcycle position of the coil stock feed from which the press can be stopped prior to the reciprocating die contacting the coil stock is chosen. With each reciprocating cycle of the die, a desired midcycle coil stock feed length is compared to a measured midcycle feed length. The press is stopped if the difference between the desired and measured feed lengths is greater than a predetermined tolerance. If the measured midcycle feed length is within the tolerance, the press operation continues.

Abstract: In an electrophotographic imaging apparatus, an imaging operation, to form an image on a continuous recording sheet, is executed. First, an unfixed toner image is transferred on the recording sheet, and fixed by a pair of fixing rollers, while the imaging operation is executed, the continuous sheet is fed. If all of the transferred images, i.e., unfixed images have been fixed, the fixing operation is stopped, and at least one of the fixing rollers is retracted.

Abstract: An apparatus and method for sensing gaps between labels adhered to a backing material in longitudinally spaced-apart positions as the backing material travels along the print path of a thermal printer. An array of light-emitting diodes oriented transverse to the print path illuminates the backing material. A fiber optic detects the light transmitted through the backing material and passes the light to a photodiode. The photodiode produces an analog electrical signal indicative of the amount of light transmitted, which varies depending on whether the light has passed through only the backing material or through both the backing material and the print media it carries. The analog signal is converted to a digital signal which is processed by a microprocessor to monitor and control the advancement of the print media and backing material through the printer.

Abstract: A web tensioning control device includes a cylindrical roller that automatically adjusts its orientation in order to equalize the tension across a moving web. Each end of the cylindrical roller is supported by a pneumatic spring. A conduit connects the two pneumatic springs so that pressurized air can shift between the springs in response to changes in the tension across the moving web. Thus, the cylindrical roller is allowed to pivot about an axis perpendicular to its roll axle so that the tension at each point across the moving web is substantially equal after encountering the roller.

Abstract: To provide a compact monitoring unit for substrate webs passing through a printing machine, typically paper webs, and thereby provide rapid response of damage control units, such as paper capturing rollers, small tears, fissures or holes in the substrate webs are sensed by locating an elongated light source (12) below the web, the light source extending beyond the lateral sides of the web to be supervised; an optical scanner (2) formed of a plurality of light guides (4) within a plastic block (5a) provides signals representative of light shining through damaged areas, and on the side of the web. The light guides then are bundled or compressed in a bundling or compression element (6), and the outputs thereof are applied to a charge coupled device sensor chip (7), directly, without intervention of optical systems, the charge coupled device being in turn connected to an evaluation and control unit which can provide "damaged web" signals to the damage control unit itself through a suitable output coupling.

Abstract: A master tape movable in a closed loop including a pinch roller transfers a mirror image to a slave tape movable in a closed loop including a capstan. A thermomagnetic layer on the slave tape has a Curie temperature above which magnetic information is destroyed and below which magnetic information can be recorded on such layer. The thermomagnetic layer is heated above the Curie temperature, thereby becoming lengthened by thermal expansion just before the slave tape reaches the capstan. A downstream portion of a peripheral surface, preferably defining a cylindrical segment, on a first guide receives a pressurized fluid for sensing the tape tension in accordance with the tape width, distance from the cylinder axis and fluid pressure. An upstream portion of the guide peripheral surface receives a vacuum adjustable to regulate tape tension in response to variations in the pressurized fluid pressure.

Abstract: An process for controlling the force exerted on a moving web of material, including a batten roller having an adjustable drive and a fixing roller having a pressure sensor. An amplifier is coupled between the pressure sensor and the adjustable drive. A web pulling device pulls the web in a downstream direction across the batten roller and the fixing roller. The pressure sensor generates a first signal representing the tensile force on the web as it passes the fixing roller. The first signal is amplified to provide a control signal to the drive for adjusting the speed of the batten roll.

Abstract: A sensor is provided to measure the diameter of a wire, and a radius of curvature of the center of the core wire of the wire is found from the obtained wire diameter and the radius of a measuring roller. The number of revolutions of the measuring roller is determined according to the radius of curvature. An appropriate radius of curvature is found for each wire to be processed, and an accurate number of revolutions can be found irrespective of the type of wire. Accordingly, the wire feeding accuracy is improved, and the preparation work is simplified.

Abstract: An apparatus for measuring and controlling lengths of movement of a continuous stock material strip which is intermittently fed by feed rollers along a predetermined path of travel to a machine which includes a reciprocally operable carriage having tooling for acting upon the strip. The apparatus comprises a strip measuring mechanism for engaging with and sensing a length of movement of the strip and generating a first signal representative of the length of movement of the strip. A controller receives the first signal from the strip measuring mechanism, and comparing the first signal to a second signal representative of a predetermined desired length of movement of the strip. The controller generates a shut-down signal to the machine if the difference between the first and second signals exceeds a predetermined shut-down limit range and generates a length error signal representing the difference between the first and second signals.

Abstract: A system for feeding and positioning articles being processed comprises: a conveying device for driving and conveying the articles; a passage detecting component for detecting the passage of a part to be detected of one part of an article, which is being thus conveyed and driven, past a forward mark point which has been set at a position spaced apart by a specific distance immediately in front of an ultimate objective stopping position; a position pulse counter for counting the timing of the passage of the part to be detected past the forward mark point; an additional feed quantity setting component for setting the quantity of feeding of an article up to the ultimate objective stopping position in accordance with the timing of passage of the part to be detected past the forward mark point; and a feed quantity control component for controlling the driving quantity of the conveying device in accordance with the said quantity feeding thus set.

Abstract: An endless tape transport apparatus is comprised of a tape transport unit having a tape feeding device for transporting an endless tape, a tape compartment unit in which the endless tape is housed, the endless tape being transported around the tape transport unit and the tape compartment unit in a loop fashion, and a tape attracting device disposed near the tape feeding device at its position in which the tape attracting device contacts the endless tape, wherein the tape attracting device is driven to attract the endless tape when the endless tape stops running.

Abstract: An automatic document feeder (ADF) for use with an electrophotographic copier, digital copier or similar image recorder for selectively feeding ordinary documents in the form of separate sheets and a continuous document in the form of computer form (CF) paper. Sprocket holes formed through the CF paper are sensed to controllably transport and stop the CF paper on the basis of the number of sensed holes. Even when the sprocket holes are partly deformed or practically lost due to breakage, the positions where they should exist are surely sensed to control the transport and stop of the CF paper. Sensors responsive to the sprocket holes do not have to be shifted in matching relation to the width of CF paper and, therefore, eliminates the need for a complicated structure.

Abstract: In an apparatus for applying a non-woven web to a moving carrier web, a straight configuration of the longitudinal edges of the non-woven web being applied to the carrier web is obtained by controlling the feeding speed of the feeder for the non-woven web in dependence on the distance between the carrier web and an unguided course of the non-woven web extending between the carrier web and a preceding fixed guide leading the non-woven web to the carrier web.

Abstract: In a process and apparatus to automatically make textile sleeves for toothed belts, a continuously fed fabric 4a is cut to obtain a plurality of cloths 7 of predetermined sizes. The cloths 7 are joined together by sewing them along respective edges that are perpendicular to the cut thus forming a continuous textile band 12. The front end 12b of the textile band 12 is locked to a predetermined position after a band moving step is carried out. During the movement, a photoelectric cell 46 and an encoder 28 identify the distance between the front end 12b of the band and the first connecting seam 12a. If this distance is less than a minimum value, the band 12 is cut upstream of the seam 12a and the moving step is repeated. If the distance exceeds the minimum value, the band is formed into a loop 44 of predetermined width.

Abstract: A wire flame spray apparatus includes a wire feed pulley driven by a motor. A first counterpulley urges a wire into engagement with the feed pulley. A detector pulley with a second counterpulley engages the wire to detect actual wire feed rate. A balance beam supports the counterpulleys. A pressure cylinder acts on the beam to increase counterpulley force on the wire in response to a lagging of actual feed rate from a predetermined feed rate so as to avert slippage of the wire on the feed pulley. A sensor senses changes in rotational speed of the detector pulley and generates signals to increase the counterpulley force. A microprocessor provides control signals for the motor and pressure cylinder.

Abstract: An apparatus having a drive pulley around which the wire is rolled, driven by a motor coupled to a speed control element. The pulley is provided with a tachometer which generates a signal proportional to the speed of movement of the wire. An extensometer, coupled to the wire, generates a signal, representative of a predetermined, ideal tension in the wire, which is compared with a set value. The resulting signal is superimposed on the tachometer signal to generate a signal to control the control element. The apparatus may also be provided with a spring biased oscillating arm located after the extensometer that has a pulley on one end, over which the wire passes. Also, a coding wheel may be provided after the oscillating arm assembly which generates a signal proportional to the speed of the wire. The coding wheel signal is converted to a signal representative of a variation in tension of the wire.

Abstract: An automatic document feeder (ADF) for use with with a copier, laser printer or similar image recorder and capable of handling a computer form (CF) document in addition to ordinary documents in the form of sheets. The ADF is selectively operable in either one of two different document transport modes, i.e., it transports initial fives pages of a CF document at a speed per page which is lower than an ordinary speed. While the lower transport speed is selected, the operator has a sufficient time to determine in which direction the CF document neatly folds along the perforation intervening between the first and second pages.

Abstract: In a level control method of controlling levels of a series of mutually joined materials when the materials pass through a catenary zone, whenever the joint travels a given length in the catenary zone, a plurality of optimum catenary curves are calculated with the position of the joint in the catenary zone as a parameter. Based upon a result of the calculation so obtained, a relationship indicative of the level of a material at the location of a catenary sensor is then calculated as a function of the position of the joint in the catenary zone. At this moment, the catenary sensor is used to detect the level of the material. Finally, the level of the material at the location of the catenary sensor is controlled with a value indicated by the above relationship being used as a target value. As a result, even when a joint between two adjoining materials having different unit weights passes through the catenary zone, the materials can travel in the catenary zone while the level is appropriately maintained.

Abstract: A system for incorporating, in the production of a continuous stream of images, by an image transfer device upon a moving web, post-production operations upon the web at various locations. Locations of a web, having a plurality of images placed thereon, output from an image transfer device are tracked. Specific operations at various locations upon the web are performed by a post-production device as the web passes through it. The web is directed from the image transfer device to the post-production device. In response to the tracking of locations upon the web, the point when a location has entered the post-production device is determined. In response to this determination, the post-production device is commanded to perform its specific operation at a connect location.

Abstract: An electrophotographic printer using a plurality of types of continuous recording forms having different page lengths, respectively, with perforations being provided between pages of each of the continuous forms. The printer is operated at least in a standby state and in a printing state. The printer comprises feed means for feeding the continuous-form recording sheet loaded into the printer, and control means for controlling the feed means in such a fashion that the perforations is located at a predetermined position when the printer is in the standby state, regardless of the page length of the recording form loaded into the printer. The predetermined position coincides either with an image-transfer position or an image-fixing position.

Abstract: An automatic document feeder (ADF) for use with an electrophotographic copier, digital copier or similar image recorder for selectively feeding ordinary documents in the form of separate sheets and a continuous document in the form of computer form (CF) paper. Sprocket holes formed through the CF paper are sensed to controllably transport and stop the CF paper on the basis of the number of sensed holes. Slippage of the CF paper apt to occur when the paper begins to be transported and when it is transported by a belt that faces a glass platen is prevented from being erroneously determined to be a jam. Cuts intervening between nearby sprocket holes for temporarily fastening a carbon to the CF paper are prevented from being sensed as the sprocket holes.

Abstract: A plotter wherein, while a sheet is being moved on a recording surface, figures, characters etc. are automatically depicted on the surface of the sheet, or the contours of figures, characters etc. are automatically cut in the surface of the sheet. In the plotter, both the side edges of the sheet are respectively held between drive rollers and corresponding pinch rollers mounted at both the sideward parts of the recording surface in opposition to each other, and the drive rollers at both the sideward parts of the recording surface are rotated synchronously to each other, whereby the sheet is moved in the rotating direction of the drive rollers on the recording surface. Each of the drive rollers is formed at its peripheral surface with milling or ruggedness for preventing the sheet from slipping.

Abstract: A relieved plastic floor tile rolling press having an automatic alignment device comprising a surface roller from which a surface substratum with plane patterns printed thereon is unwound, a pressing roller on which recessed carves shaped the same as the plane patterns are formed to form relieved patterns on the plastic tile, and a sensing device to detect the lateral deviation and also detect the longitudinal location of the surface substratum. The sensing device also comprises a sensor to detect the rotational location of the pressing roller. The information detected by the sensing device is then sent to microprocessors to adjust the lateral location of the surface substratum and eliminate the difference between the longitudinal location of the surface substratum and the rotational location of the pressing roller.

Abstract: A wire feed apparatus for a wire cut electric discharge machining apparatus, capable of moving a wire conveyor belt from an automatic wire extension position to a non-wire-transfer shunt position at the time of electric discharge machining, thereby preventing wear of the belts and reducing variation in the wire feed speed. The apparatus includes first and second conveyor belts selectively operated in accordance with predetermined conditions for wire feeding. At the time of automatic wire extension, an air cylinder of a wire feed mechanism is driven to move the second conveyor belt from a non-wire-transfer shunt position to the automatic wire extension position using a parallel link mechanism. The second conveyor belt is pressed against the first conveyor belt at the automatic wire extension position.

Abstract: A web drive cyclically moves a web a fixed distance. First and second spaced draw roll units include separate servo motors. Separate programmed controllers are connected to energize the servo drives with a time motion profile including acceleration and deceleration periods to move the web in a fixed time period. The one programmed controller generates the profile program each cycle during the execution of program to move the web the next cycle. The generated program is down-loaded to the second controller to duplicate energization of the second servo motor. A dancer unit between the drive rolls maintains the tension with a change in web length and includes a movable roll unit. A potentiometer sensor is coupled to the roll unit and establishes an output signal voltage proportional to the direction of the web change and to the length thereof.

Abstract: In a printing device such as a laser beam printer utilizing a continuous-form recording sheet, two controlling members are provided for controlling the recording sheet to be discharged from the printing device after a printing operation, and for controlling the recording sheet so as to be located at a position from which a printing operation is restarted. Thus, recording sheet is not wasted when the output begins.

Abstract: A microprocessor controlled thermal printer particularly usable in a hand-held labeler for printing labels on a composite web detects indices on the web and utilizes the detected indices to position the labels relative to the print head. The printer utilizes an improved index detection system that compensates for variations in index size and density and for variations in sensor sensitivity by detecting both the leading and trailing edges of an index and utilizing the distance between the detected leading and trailing edges to determine the length of the index. By dividing the length thus determined by two, and by advancing the web by this amount after the detection of the leading edge of an index, the center of the index can be accurately located, and the web can be accurately registered at any desired position relative to the center of the index.

Abstract: A microprocessor controller thermal printer particularly usable in a hand-held labeler for printing labels on a composite web detects indices on the web and automatically adjusts the distance that the web is advanced based on a measurement of the distance between indices made during a paper loading sequence. The printer includes automatic jam detection that measures the length of time that one of the indices is being detected and provides a jam indication if it is detected for more than a predetermined time period. A solenoid operated braking mechanism retains the web in position upon completion of a printing cycle to prevent the web from being moved relative to the print head while the label is being applied.

Abstract: A splicing apparatus for joining a trailing end of a first sheet to a leading end of a second sheet comprises a first servomechanism including a first drive for engaging and advancing the first sheet in a direction of advance; a second servomechanism including a second drive for engaging the first sheet upstream of the first drive; a splicing device for joining the trailing and leading ends to one another upstream of the second drive; a sensor for generating a signal when the trailing end of the first sheet passes a predetermined location upstream of the splicing device; and a computer connected to the first and second servomechanisms, the splicing device and the sensor for reducing the speed of the advancing first sheet and for subsequently effecting a joining operation of the splicing device upon receiving the signal from the sensor; and a sheet length compensating device engaging the first sheet at a location between the first and second drive for reducing or increasing the length of the first sheet betwee

Abstract: A perforated paper feed mechanism such as a tractor has an optical system for detecting the presence of the form and particularly the motion of the form and utilizes a reflector which may be mounted on the lid of the tractor at one end of the tractor (where the paper enters or leaves the tractor). The optical system may be implemented by a prism which folds the path of light from a light source (an LED) to a photo detector (a photo-transistor) the path is aligned with the perforations in the paper. Since the perforations are spaced, the photo transistor provides a train of pulses as the paper is fed by the tractor. A pulse detector responds to the presence or absence of pulses within a given period of time comparable to the time when perforations are fed past the optical path. An output from the detector thus indicates whether the paper is in motion and is being fed by the tractor. Failure to receive pulses indicates either the absence of paper (paper out) or a jam in the feed.

Abstract: A paper advance control for a progressive X,Y plotter with unidirectional paper movement senses the actual advancement of the paper and controls the drive to a take-up roll in such a way as to keep the speed of advancement constant over the major portion of its advancement. It also through the same sensor keeps informed of its actual paper position and stops the paper with accurate positioning at the end of an advancement, its stopping procedure including a pre-stop slow down of the paper speed.