A control system for controlling operation of main and secondary drive units in a web winder system to provide tension control of a continuous material web is disclosed. The control system causes the main drive unit to operate in a velocity mode to set a linear velocity of the continuous material web. The control system receives inputs from tension and speed detectors in the web winder system that detect a tension and speed of the continuous material web and causes the secondary drive unit to operate in a modified torque regulated closed-loop tension control mode so as to control a tension in the web material, with the control system causing the secondary drive unit to operate according to a torque regulated closed-loop tension control mode and integrate a speed feedback loop into the torque regulated closed-loop tension control mode so as to introduce active damping into the tension control.

An apparatus for controlling conveyance between rollers includes: a tension-control-amount-detector; a speed-shaft-speed-controller; a tension-shaft-speed-controller; a synchronous-speed-command-generation-unit synchronizing the speed-shaft speed command with a tension-shaft reference speed command; a tension-control-calculation-unit outputting a tension-control correction value based on proportional compensation based on a proportional gain, and integral compensation based on an integral gain; an adjustment-execution-command-generation-unit outputting an adjustment execution command during an automatic adjustment period; a binary-output-unit outputting one of positive and negative values of the additional-value amplitude as an additional value in adjustment during the automatic adjustment period; a tension-shaft-speed-command-generation-unit outputting a tension-shaft speed command based on the tension-shaft reference speed command, the tension-control correction value and the additional value in adjustment; and a gain-calculation-unit calculating a proportional gain and an integral gain based on a period and an amplitude of the tension control deviation for the automatic adjustment period.

A sheet transporting apparatus is provided, including a transport mechanism provided with a roller, a motor, a controller, and a measuring input unit, wherein a transport route has a curved area for inverting the sheet, and the controller is constructed such that the control on the motor is executed by a closed loop control system by using a measured value of an control output at an initial stage of the transport of a sheet from a tray, and the control on the motor is switched from the control performed by the closed loop control system to control performed by an open loop control system on condition that a preset phenomenon arises after the sheet is taken out of the tray.

A sheet transporting apparatus is provided, including a transport mechanism provided with a roller, a motor, a controller, and a measuring input unit, wherein a transport route has a curved area for inverting the sheet, and the controller is constructed such that the control on the motor is executed by a closed loop control system by using a measured value of an control output at an initial stage of the transport of a sheet from a tray, and the control on the motor is switched from the control performed by the closed loop control system to control performed by an open loop control system on condition that a preset phenomenon arises after the sheet is taken out of the tray.

A rope replacement apparatus includes: a rope conveying mechanism, used for driving a first rope to move along a moving path of a second rope, so as to replace the second rope; a first detection part, used for detecting a first moving speed V.sub.1 of the first rope output by the rope conveying mechanism; the first detection part being installed on the rope conveying mechanism; a second detection part, used for detecting a second moving speed V.sub.2 of the second rope outside the rope conveying mechanism; the second detection part being installed on the moving path of the second rope; a control part, used for adjusting V.sub.1 according to the difference between V.sub.1 and V.sub.2; the first detection part and the second detection part being both in communication connection with the control part. The rope replacement apparatus improves rope replacement efficiency and slipping can be reduced.

A media conveying apparatus includes a feed table on which a medium is placed, a conveyor to convey the medium placed on the feed table, a sensor to detect floating of the medium conveyed by the conveyor, an ejector to eject the medium conveyed by the conveyor, an ejection tray located above the feed table to stack the medium ejected by the ejector, and an extension tray connected to a downstream side of the ejection tray in a media ejection direction. In a state where the medium ejected from the ejector is stacked on the ejection tray and the extension tray, a lower end portion of the extension tray on an upstream side in the media ejection direction is located closer to the feed table than a lower end portion of the ejection tray on a downstream side in the media ejection direction.

The rewinding machine (1) includes: a winding station (3) with winding members (5, 7) operated by winding motors (8.1, 8.2); an unwinder (31.1, 31.2) with an unwinding member (35.1, 35.2) operated by at least one unwinding motor (38.1, 38.2); a guide roller (43.1, 43.2) along a feed path (P) of the web material (N, N2). There is associated with the guide roller (43.1,43.2) at least one load sensor (42.1, 42.2), adapted to detect a parameter proportional to the tension of the web material (N; N2) guided around the guide roller (43.1,43.2). There is also provided a control unit (71) adapted to modulate a difference in speed between the winding members (5, 7) and the unwinding member (35.1,35.2) as a function of a signal corning from the load sensor (42.1,42.2).

The invention discloses a clearance adjusting apparatus, a clearance adjusting method and a conveyance device. The clearance adjusting apparatus is used for adjusting a clearance between two opposite rollers and comprises: a driver for driving the roller to move up and down, at least one of the rollers being movable relative to the other; and a controller that stores a predetermined clearance scope being connected with the driver for controlling the driver to drive the movable roller to move up and down, so that the clearance between the two rollers falls into the predetermined clearance scope.

The roller-to-roller conveyance control apparatus includes an amplitude target setting unit that sets an amplitude target value of the tension deviation; an adjustment execution command generation unit that provides a command to adjust the control gain; an adjustment manipulated-variable output unit that outputs an adjustment manipulated variable; a manipulated-variable amplitude determination unit that increases the amplitude of the adjustment manipulated variable until the amplitude of the tension deviation becomes larger than the amplitude target value; and a control-gain calculation device that calculates the control gain from the amplitude and the vibration period of the tension deviation. A tension-shaft speed controller controls a tension-control-shaft motor on the basis of the line speed reference and the adjustment manipulated variable during the adjustment of the control gain.

A printer 1 has a movable member 27 that can move following change in the tension on recording paper 3 between a roll paper compartment 7 and a conveyance mechanism 12 on the paper conveyance path 8. When recording paper 3 of which the end is glued to the core 2a of a paper roll 2 runs out, the tension on the recording paper 3 rises and the movable member 27 goes to a tension-side error determination range E1 in its range of allowable movement E0. When the movable member 27 is in the tension-side error determination range E1, the time the movable member 27 remains in the tension-side error determination range E1 is counted, and if this measured time exceeds an error determination time, an error detection unit 38 detects an error. No-paper errors can therefore be detected without using a dedicated sensor.