Abstract: Provided is a conveying apparatus for conveying a molded body for heat exchanger fins that can achieve high-speed conveyance of a molded body for heat exchanger fins, prevent generation of noise during conveyance, and have a smaller size.

Abstract: A sprocket for a tracked vehicle. The sprocket has a plurality of sockets for engaging drive lugs on an inner surface of a track driven by the sprocket. The sprocket also including a support surface for engaging with an inner surface of the track and which is in rolling contact with the inner surface of the track.

Abstract: In an example, an edge holder may include a strap, a first end cap fixed to the strap, and a second end cap fixed to an opposite end of the strap from the first end cap. The second end cap may include a fixed end and a cam engaged with the fixed end. The cam may adjustably tension the strap between the first end cap and the second end cap.

Abstract: An endless track for traction of an off-road vehicle, such as an agricultural vehicle, an industrial vehicle (e.g., a construction vehicle) or a military vehicle, is provided. The endless track a plurality of elastomeric lugs, such as drive/guide lugs projecting from the inner surface and/or traction lugs projecting from the ground-engaging outer surface. An elastomeric lug may have a material composition defining an arrangement of zones of different materials which comprises a plurality of zones of different elastomeric materials, may exhibit a desired variation of a material property (e.g., across the arrangement of zones of different materials. A zone of the elastomeric lug may have a dedicated function, such as a sacrificial zone or a wear indicator zone. An elastomeric drive lug may comprise an uneven drive surface, such as an angled or curved surface, for engaging a drive member of a drive wheel of the vehicle.

Abstract: A printer capable of preventing clogging the printhead nozzles due to paper dust produced from sprocket holes in continuous paper, and preventing the printhead from ejecting ink droplets except on the continuous paper, has a printhead that ejects ink droplets toward continuous paper having sprocket holes formed along both sides of the paper width; a cover member that covers the edge part of the width of the continuous paper where sprocket holes are formed in the range of the printhead in the conveyance direction of the continuous paper, and can move in the paper width direction; and a detection mechanism that detects the position of the cover member in the paper width direction.

Abstract: A feeding apparatus feeds a metal strip with cutaway portions in a conveying direction and includes: a reference plate on which the metal strip is placed and in which a slit is formed; moving bodies that are provided below the reference plate and are moved by driving means parallel to the reference plate in the conveying direction; feed pins that advance into the cutaway portions, are provided on the moving bodies so as to move up and down with respect to the reference plate, and pull the metal strip in the conveying direction when the moving bodies move; and at least one guide portion that contacts a side surface on an opposite side of the metal strip to the cutaway portions and guides conveyance of the metal strip.

Abstract: A printer has a tractor unit with a simple configuration that can prevent the feed holes in continuous paper from disengaging the engagement pins of the tractor unit during conveyance. The tractor unit of the printer has a pair of tractors that hold the continuous paper with tractor pins (engagement pins) engaged in sprocket holes (feed holes), a drive shaft and a support shaft that support the pair of tractors, and a frame that supports the drive shaft and support shaft. The first tractor is fixed in position to the support shaft after engaging and holding one side of the continuous paper, but the support shaft is supported on the frame movably widthwise to the printer. If the continuous paper becomes skewed, the first tractor moves with the support shaft widthwise to the printer following the skew, and the sprocket holes therefore do not disengage the tractor pins.

Abstract: According to one embodiment, a tractor comprises a guide shaft, a first belt unit, a second belt unit, a fixing unit and a connecting unit. The first belt unit is supported by the guide shaft so as to move in an axis direction of the guide shaft. The second belt unit is arranged to face the first belt unit in the axis direction of the guide shaft and supported by the guide shaft. The fixing unit, which is movably supported by the guide shaft in the axis direction of the guide shaft and is capable of being fixed on the guide shaft. The connecting unit configured to connect the first belt unit to the fixing unit with a clearance in the axis direction of the guide shaft.

Abstract: According to one embodiment, a tractor comprises a pin belt, a pair of rotating units and a roller. The pin belt configured as an endless belt, which has a plurality of pins on the outer peripheral surface thereof, wherein the pins are respectively inserted into feeding holes formed on a tractor paper, and the pin belt rotates to convey the tractor paper. The pair of rotating units configured to rotate the pin belt. The roller, which is arranged between the pair of rotating units, with a groove on the outer peripheral surface thereof, wherein the front end of the pin is fitted into the groove, so that the front end of the pin is abutted against the groove to space between the outer peripheral surface of the pin belt and the outer peripheral surface of the roller.

Abstract: At least one paper web is drawn into a web-fed rotary printing press. A draw-in device is provided with permanently fixed pointed bars or spikes. These can be moved or oriented so that they penetrate the paper web only during drawing in of the web into the printing press.

Abstract: A roller and a device for guiding paper w bs to a unit of a rotary printing press includes paper web traction devices. These traction devices may be endless or of finite length. The roller that cooperates with these traction devices includes a passage that receives the traction devices. The axial width of the passage is adjustable.

Abstract: A roller and a device for guiding paper webs to a unit of a rotary printing press includes paper web traction devices. These traction devices may be endless or of finite length. The roller that cooperates with these traction devices includes a passage that receives the traction devices. The axial width of the passage is adjustable.

Abstract: An apparatus for reducing friction, tearing, or wrinkling of the surface of a single-ply or multiple-ply continuous medium being fed to a processing station by either sprocket engagement of an edge-perforated medium or pinch roller pressure engagement of the medium as the medium moves in a vertically-oriented path, said reduction being effectuated through selectively altering the contact path length of guides supporting the medium in a direction reducing any friction forces.

Abstract: A system and method for utilizing web that is free of tractor pin feed holes comprises the driving of the web along a predetermined path within the utilization device. A web guide is provided in an upstream location from a utilization device element. The guide engages width-wise edges of the web and forms the web into a trough to stiffen the web. A drive roller and a follower roller impinge upon opposing sides of the web and rotate to drive the web through the guide. The drive roller is located adjacent to the guide according to a preferred embodiment. A registration controller is utilized to synchronize the movement of the web with the operation of the utilization device element. The controller includes a drive controller that controls the speed of either the drive roller or the utilization device element to maintain the web and the utilization device element in appropriate synchronization.

Abstract: A continuous paper treating apparatus is provided which includes a tractor for feeding continuous paper and a paper treating unit for treating the paper. The tractor includes a driving belt provided with tractor pins, a tractor lid for covering the driving belt, a support base having a paper support surface for supporting the continuous paper. The tractor also includes a presser member supported by the tractor lid. The presser member is variable in position and posture relative to the tractor lid, and has a pressing surface for pressing the paper. In the tractor, use is made of springs for urging the presser member toward the paper supporting surface, so that the pressing surface presses the continuous paper onto the paper supporting surface.

Abstract: A system and method for utilizing web that is free of tractor pin feed holes comprises the driving of the web along a predetermined path within the utilization device. A web guide is provided in an upstream location from a utilization device element. The guide engages width-wise edges of the web and forms the web into a trough to stiffen the web. A drive roller and a follower roller impinge upon opposing sides of the web and rotate to drive the web through the guide. The drive roller is located adjacent to the guide according to a preferred embodiment. A registration controller is utilized to synchronize the movement of the web with the operation of the utilization device element. The controller includes a drive controller that controls the speed of either the drive roller or the utilization device element to maintain the web and the utilization device element in appropriate synchronization.

Abstract: A system and method for utilizing web that is free of tractor pin feed holes comprises the driving of the web along a predetermined path within the utilization device. A web guide is provided in an upstream location from a utilization device element. The guide engages width-wise edges of the web and forms the web into a trough to stiffen the web. A drive roller and a follower roller impinge upon opposing sides of the web and rotate to drive the web through the guide. The drive roller is located adjacent to the guide according to a preferred embodiment. A registration controller is utilized to synchronize the movement of the web with the operation of the utilization device element. The controller includes a drive controller that controls the speed of either the drive roller or the utilization device element to maintain the web and the utilization device element in appropriate synchronization.

Abstract: A paper transfer apparatus is provided which is incorporated in an electrophotographic printer having a photosensitive drum for printing on elongated paper. The paper transfer apparatus serves to transfer the elongated paper along a transfer path extending via the photosensitive drum. The paper transfer apparatus includes a discharge or scuff roller for pulling the elongated paper in a transferring direction. The discharge roller is spaced downstream from the photosensitive drum. The paper transfer apparatus also includes a pair of tractors for advancing the elongated paper along the transfer path. The tractors are spaced upstream from the photosensitive drum. Each of the tractors is provided with a presser member supported by a tractor lid of the tractor. The presser member serves to apply friction to the elongated paper when the tractor lid is in closed position.

Abstract: A yarn delivery device for a textile machine has at least one yarn delivery roller, and a drive device for a propulsion of the delivery roller, the drive device including a drive belt, a drive roller with a peripheral section alterable in diameter and at least in part in part looped around by the drive belt, and a tensioning unit with a guide member acting on the drive belt, the tensioning unit including a controller for producing at least one larger belt tension for normal operation of the delivery roller and a smaller belt tension for alteration of the diameter of the peripheral section of the drive roller.

Abstract: A system and method for utilizing web that is free of tractor pin feed holes comprises the driving of the web along a predetermined path within the utilization device. A web guide is provided in an upstream location from a utilization device element. The guide engages width-wise edges of the web and forms the web into a trough to stiffen the web. A drive roller and a follower roller impinge upon opposing sides of the web and rotate to drive the web through the guide. The drive roller is located adjacent to the guide according to a preferred embodiment. A registration controller is utilized to synchronize the movement of the web with the operation of the utilization device element. The controller includes a drive controller that controls the speed of either the drive roller or the utilization device element to maintain the web and the utilization device element in appropriate synchronization.

Abstract: A system for utilizing web that is free of tractor pin feed holes comprises the driving of the web along a predetermined path within the utilization device. A web guide is provided in an upstream location from a utilization device element. The guide engages width-wise edges of the web and forms the web into a trough to stiffen the web. A drive roller and a follower roller impinge upon opposing sides of the web and rotate to drive the web through the guide. The drive roller is located adjacent to the guide according to a preferred embodiment. A registration controller is utilized to synchronize the movement of the web with the operation of the utilization device element. The controller includes a drive controller that controls the speed of either the drive roller or the utilization device element to maintain the web and the utilization device element in appropriate synchronization.

Abstract: A web handling apparatus for delivering thin web materials comprises a support frame; a pair of laterally spaced-apart and substantially longitudinally extending frame rails carried by the support frame and positioned to support a web of material delivered therebetween. It also includes a support rail affixed outwardly of each frame rail adjacent an exit end, the support rails configured to support the pair of frame rails from the support frame wherein unobstructed access between the frame rails is provided from the exit end. In addition, it includes an adjustment mechanism positioned to adjust relative positioning of the pair of frame rails in spaced-apart relation.

Abstract: A second frame 12 is arranged at a predetermined position with respect to a drive sprocket 15 engaged with a drive shaft DS through a substantially true-circular hole shape drive bearing bore 14, and a transferring belt 25 is supported by a belt guide 18 integrally incorporated with the second frame 12 under a suitable tension while a predetermined positional relationship is maintained between the transferring belt 25 and the drive sprocket 15.

Abstract: A number of identified actuators are adjusted by identical absolute values which have an effect on a web end only within a noise level. A series of transverse profile measurements are then carried out, from which in each case a previously determined mean value of the transverse profile is subtracted and the results are superimposed until a number of measuring signals, which corresponds to the actuators to be identified, stands out in a clearly recognizable fashion in terms of amplitude and/or shape from the superimposed noise components of the transverse profile.

Abstract: Apparatus for transporting a web of paper having tractor holes along only one margin thereof.

Abstract: A sheet feed mechanism utilizing a continuous form sheet, with a plurality of equally spaced sprocket holes formed on both side edges thereof in the direction along a straight sheet feed path, is fed between a photoconductive member and transfer member. Each side of the sheet feed mechanism includes an endless tractor belt looped between two feed rollers disposed upstream and downstream of the transfer member, respectively. In one aspect, engaging pins are provided on the circumferential surface of the feed rollers and engaging holes on the tractor belt spaced at the same interval as the holes of the continuous form sheet, to feed the sheet by engagement of the engaging pins and the sprocket holes through the engaging holes. In another aspect, the endless belt is provided with the engaging pins and a regulation member for moving the tractor belt such that a portion of its upper part is separated from the photoconductive member.

Abstract: A sheet feed mechanism including a first tractor slidably mounted onto a drive shaft and a guide shaft respectively disposed between a first and a second frame of the printer. A wire is passed through the first tractor and is stretched between the first and second frames by the use of a tension spring or another energizing device connected to one end of the wire adjacent the first frame. Both the first tractor and the second tractor have pin belts with a plurality of pins disposed thereon for aligning and meshing with the holes in the sides of successive sheets of paper.

Abstract: An electrophotographic imaging apparatus using a continuous form recording sheet is provided, in which the recording sheet carrying an unfixed toner image is passed through a fixing device and the toner image is fixed thereon. The imaging apparatus includes a recording sheet transporting device, disposed on the downstream side of the fixing device, to ensure that the recording sheet is stably transported and discharged from the imaging apparatus.

Abstract: Each of a pair of spaced apart paper feed mechanisms within the paper feed system of a dot matrix line printer has opposite upper and lower portions thereof slightly angled relative to each other and disposed on opposite sides of and close to an elongated print station having a platen at one side thereof on which the paper feed mechanisms are mounted. Guides within the print station direct a length of paper introduced onto one portion of the paper feed mechanism through the print station and onto the other portion. Each paper feed mechanism is locked in a desired position on the platen using a manually operated lever arm arrangement having a mechanical advantage. Phasing or pitch adjustment between the opposite portions of each paper feed mechanism is accomplished by either of two arrangements which vary the position of a pulley engaging an endless belt between the opposite portions in combination with an opposite spring mounted pulley which bears against the inside of and tensions the endless belt.

Abstract: A paper feed device for feeding continuous stationery (12), provided with lateral perforations, into the transport elements (44) of a transfer station (17) of a non-mechanical printing device, in which paper feed device the transfer station (17) has in the transport direction of the continuous stationery paper transport belts (44) which are motor-driven both on the input and on the output side and engage in the lateral perforation of the continuous stationery (12), and a paper brake (31), which can be actuated when required, is arranged upstream of the input-side transport elements (47) in the transport direction. A switch device (D, C) is provided to feed the continuous stationery accurately after the continuous stationery (12) has been deposited in the output-side paper transport elements (48), which switch device drives the output-side paper transport elements (48) at least for a predeterminable feed time when the paper brake (31) is activated.

Abstract: A printer, for printing on continuous recording paper, includes tractors disposed in the recording paper feed path of the printer, with each of the tractors circumferentially travelling in synchronism with movement of the continuous recording paper when the tractors engage feed holes of the continuous paper. When no printing operation is performed, travel of the tractors can be prevented by operation of an electromagnetic clutch, or a combination of one way clutches. Further, the printer uses an electrophotographic method wherein when no printing operation is performed, a transfer charger or fixing roller can be retracted from an operational position. A lever, associated with movement of the transfer charge or fixing roller, is pressed against and locked with the pulley fixed to the rotating shaft of each of the tractors to thereby prohibit the movement of the tractor.

Abstract: A relatively low cost, low friction plastic needle bearing assembly uses a unitary plastic circular member with multiple frangibly attached substantially cylindrical needles axially inserted into a cover. A plastic needle separator housing element provides a race and is in axial registration with the frangibly attached needles. A shaft (on which a sprocket of a web feed device or tractor is mounted), upon axial insertion through the member to which the needles are attached, frees the multiple needles from the frangible attachment to the member and ejects the member from the cover leaving the needle bearings captured by the race in the cover.

Abstract: An articulating paper sensor for sensing the presence of continuous paper in a tractor drive assembly for transporting continuous paper along a travel path. The articulating paper sensor comprises a body having a portion including a sensing element for detecting continuous paper and producing a signal in response to such detection. The body is pivotably attached to the tractor drive assembly. When the tractor drive assembly is positioned to have continuous paper loaded therein, the body is moved to a remote location relative to the continuous paper travel path; and when the tractor drive assembly is positioned to transport continuous paper along the travel path, the body is moved to a location relative to the travel path such that the sensing element detects the presence of continuous paper in the travel path.

Abstract: Apparatus for use with a printer which has a pair of tractors that engage sprocket holes in the paper to adjust for different paper widths or to adjust the lateral position of the paper. The apparatus comprises a pair of coaxial lead screws, one attached to a rotatable shaft and the second rotatable on the shaft adjacent to and relative to the one lead screw. One tractor is coupled to each lead screw. Rotation of the one lead screw is obtained by a knob keyed to an end of the rotatable shaft. Rotation of the second lead screw is prevented during rotation of the knob by spring loaded fingers with detent elements engageable with detention gearing on the end of the second lead screw. Rotation of both screws is obtained by rotation and axial movement of the knob on the shaft so that a cam surface on the knob engages cams of the spring fingers to disengage detent elements from the detention gearing and drive gearing on the knob engages drive gearing on the second lead screw.

Abstract: A sheet feeding device for feeding paper in a predetermined direction while a paper presser plate keeps the paper pressed to a sheet feeding mechanism. The sectional shape of the paper presser plate is modified according to the distribution of a bending moment applied to the paper presser plate so as to prevent creep.

Abstract: To prevent concurrent mounting of two tractor units on an upstream side and a downstream side of a platen of a printer, a rocker member is pivotally mounted by a pivot pin on a side plate of a chassis to which the tractor unit is attachable. The rocker member has an upper end portion disposed close to an upper lock pin of a downstream side mounting portion. The lower end portion of the rocker member is disposed close to a lower lock pin of an upstream side mounting portion. When the tractor unit is locked with the lower lock pin, the lower end portion of the rocker member is firmly locked in position against rotation, so that the upper end portion of the rocker member is no longer separable from the upper rock pin, and hence, is able to prevent another tractor unit from moving into that portion.

Abstract: A tractor feed mechanism combines, in a unitary assembly, components which provide the capabilities of separate, independent, left and right-hand tractors and their support and drive shafts. The assembly has fewer parts than a tractor feed using separate tractors thereby reducing the cost and increasing the reliability of the feed mechanism. In the unitary tractor feed, endless tractor belts are positioned by lid belt guide members which are slidable on a bar having a surface which provides a platform which sets the height of the belts, while the web is disposed on a gap between an upwardly facing surface of the guide members and a downwardly facing surface of the lid. The bar and a sprocket which engages the belt extends laterally (width-wise) of the web a distance at least as wide as the longest web to be fed.

Abstract: A paper feeding tractor in which perforated paper is fed by a pin carrying feed belt includes a feed belt driving sprocket which is housed between a pair of side frames. Two side faces of an inner circumferential portion of the sprocket body, except an outer circumferential portion formed with teeth, are formed with round fitting protuberances concentric with an axial hole therein such that the inner circumferential portion of the sprocket body is thinner than the outer circumferential portion. Thus, contact between the sprocket and the drive shaft is reduced to a relatively small sliding resistance. Paper can be moved in the axial direction of the drive shaft by a small force. During paper feed, any phase difference in rotation between the drive shaft and the sprocket can be eliminated. Alternatively, the feeding sprocket and a belt reception rotary member are housed within an auxiliary frame structure which is fit within and longitudinally slidable with respect to the main frame structure.

Abstract: A paper feed apparatus including a pair of side frames connected together so as to face one another with a predetermined gap therebetween, an endless feed belt mounted between the pair of side frames, a driving sprocket engaged with the endless feed belt and mounted between the pair of side frames at a first end thereof, and a belt receiver mounted between the pair of side frames at a second end thereof and supporting the endless feed belt. The driving sprocket and belt receiver have the endless feed belt trained thereabout with a predetermined amount of slack, such that the upper and lower runs of the belt are substantially linear. A feed belt supporter is mounted to the pair of side frames so as to contact an outer surface of and support the lower run of the endless feed belt so as to prevent the predetermined slack from gathering at the lower run of the endless feed belt.

Abstract: A clamp is used for clamping a paper feed tractor to a support shaft at a predetermined distance from another paper feed tractor. The clamp comprises a semi-cylindrical elongated clamp guide member which is cantilevered from a frame of the paper feed tractor, and a cylindrical clamp member rotatably mounted about the clamp guide member. The clamp guide member has a clamping inner peripheral surface adapted to complementarily engage the support shaft, a first outer peripheral surface, a second outer peripheral surface having a radius of curvature larger than the first outer peripheral surface and a sloped outer peripheral portion joining the first and second outer peripheral surfaces.

Abstract: A paper feed mechanism for feeding fan-fold paper into a printer, a typewriter, or the like has a drive roller, an idler roller, and a pin belt trained around the drive and idler rollers and having a series of pins for engaging in perforations of the fan-fold paper. The fan-fold paper is guided by first and second paper holders that are angularly supported on a frame. The first paper roller is of an arcuate shape and extending along an outer periphery of the drive roller. The first paper roller is angularly movably supported on the second paper roller. The second paper roller extends along a straight portion of the pin belt between the drive and idler rollers.

Abstract: A document feed tractor in which pins which drive the paper upon entry into perforations in margins of the paper along the edges thereof are connected to a belt on beams cantilever mounted thereto. A guide and support bar holds the beams and the pins down so that they travel along a linear path entering and leaving the perforations at opposite ends of the path. In order to drive the paper precisely, especially at high speeds where the belt and pins start and stop, without denting or ticking the paper and to maintain alignment of multi-part documents (without shingling), an adjustable shelf is located on the inside of the tractor so that the paper overlies the shelf. The elevation of the shelf with respect to the pins is selectively set in accordance with the thickness of the paper. The tractor can then be set so that the web is maintained at the center line or pitch line of the belt, thereby insuring precision feeding of the form even at high speeds with rapid accelerations and decelerations.

Abstract: A tractor mechanism has an endless pin belt entrained around spaced drive and idler sprockets mounted between a pair of frame members. The idler sprocket is supported by a carrier movable longitudinally by springs to apply tension to the belt. The edges of the belt overhang gear teeth of the belt and are prevented from contact with the frame members by the gear teeth engaging an endless vertical wall on one of the frame members. The frame members and sprocket carrier are molded polycarbonate with carbon fiber and solid lubricant fillers to reduce electrostatic charge buildup and wear of the belt. The frame members are bolted together to clamp the sprocket carrier in place to maintain the belt tension applied by the springs. The sprocket carrier and frame members have aligned elongate openings for receiving a tractor guide shaft with a concentric plastic tube, the latter being attached to a retainer plate held loosely between the sprocket carrier and a frame member.

Abstract: A clamp for a paper feed tractor for clamping a paper feed tractor to a support shaft. Such a clamp is used for clamping the paper feed tractor to the support shaft at a predetermined distance from another paper feed tractor which corresponds to a width of a perforated paper to be fed by the tractors. The clamp comprises a cylindrical holder member which is cantilevered from a frame of the paper feed tractor, and a cylindrical clamp member rotatably mounted about the holder member. The holder member comprises a pair of semi-cylindrical holder plates, each of which has two outer peripheral surface portions of differing radii and a sloped outer peripheral portion joining the two outer peripheral surface portions. The larger radius outer peripheral surface portion of each holder plate is arranged diametrically opposite from the other.

Abstract: In a sheet feed tractor, a lid confines a paper sheet on a frame surface when the paper sheet is conveyed on a belt. The lid is constructed so that it can overrun and return to its normal open position. The lid is constructed so as to include a lid member rotatable between a closed position spaced closely adjacent the surface of the frame so as to confine the paper sheet and an open position spaced away from the surface. The lid member has at one side edge thereof a pair of hinge pins disposed with a space therebetween and projecting over one side of the frame. The frame includes a pair of hinges projecting from one side of the frame and has the hinge pins of the lid member rotatably mounted thereto. The hinges of the frame include grooves opening towards the outside of the sheet feed tractor and are adapted to pivotally receive the hinge pins of the lid member.

Abstract: A printer tractor drive assembly is specified having a belt with pins which engage paper which is to be moved across a print station. The assembly includes a split lid covering the paper being driven. One portion of the split lid can be opened to expose and remove the paper along its perforations, while the other portion of the split lid retains the paper on the tractor pins.

Abstract: A paper feeder for printers having front and back pin tractor assemblies disposed on opposite sides of a platen roller with respect to the paper feed route. Each tractor has a plurality of pins which are rotatable so as to convey the continuous paper. A reversible drive source is coupled to both the pin tractors. A clutch selectively decouples the drive source from the front pin tractors in accordance with the rotational direction of the drive source. A switch mechanism independent of the clutch also selectively decouples the front pin tractor from the drive source. The described structure allows paper stack to be automatically removed from between the tractors.

Abstract: A cover is disclosed for a paper feed tractor having first and second side frames, a paper receiving plate extending perpendicularly from the second side frame and having a hole formed therein, and a paper exhaustion detector mounted to the second side frame. The paper exhaust detector of the paper feed tractor includes a microswitch with an upwardly biased plunger, and an actuator pressed upwardly by the plunger and pivotable between a first position in which it detects the presence of paper and a second position in which it detects the absence of paper. The cover of the present invention includes a plate, and elongated ribs projecting downwardly from the bottom surface of the plate on opposing sides of an elongated slot formed through the plate.

Abstract: A printer including at least two tractor unit mounting sections upstream of the print position in the sheet feed direction, and at least one tractor unit can be mounted on either of these tractor unit mounting sections. The sheet feeding direction can thus be selected freely in accordance with the web replacement frequency or the printer installation location merely by changing the mounting position of the tractor unit. If the number of tractor units is increased, a plurality of webs can be set up simultaneously and used selectively.

Abstract: The drive assembly for a form feeding tractor has a flexible endless belt comprising an endless band member of synthetic resin with a generrally planar outer surface and metallic drive pins spaced about its circumference. The band member has a series of spaced apart drive sections each with a plurality of drive teeth extending transversely thereof on its inner surface, and the metallic drive pins are disposed in the spaces between the drive sections. The pins have a base section which extends through the band member with a circumferential groove intermediate its length and into which the band member extends, and the band member has platform portions on its inner surface which extend about the base portions on the pins.