An image forming apparatus has a sheet feed portion, a conveying portion, a control portion, a first sensor having the detection position at a first position in the sheet conveying passage, and a second sensor having the detection position at a second position downstream of the first position in the sheet conveying direction. The control portion performs first sensing to sense whether the sheet's rear end has passed the first position within a first time of the start of the feeding and second sensing to sense whether the sheet's rear end has passed the second position within a second time of the start of the feeding, Even if the control portion is unable to sense passage of the sheet's rear end in the first sensing, when it senses passage of the sheet's rear end in the second sensing, it makes the conveying portion continue feeding the sheet.

An image forming apparatus has a sheet feed portion, a conveying portion, a control portion, a first sensor having the detection position at a first position in the sheet conveying passage, and a second sensor having the detection position at a second position downstream of the first position in the sheet conveying direction. The control portion performs first sensing to sense whether the sheet's rear end has passed the first position within a first time of the start of the feeding and second sensing to sense whether the sheet's rear end has passed the second position within a second time of the start of the feeding, Even if the control portion is unable to sense passage of the sheet's rear end in the first sensing, when it senses passage of the sheet's rear end in the second sensing, it makes the conveying portion continue feeding the sheet.

It aims to solve a problem that in a printer including a mixture of sheet feeding devices for which points of view regarding the presence/absence of sheets are different, such as a deck-type sheet feeder and a manual feed tray, appropriate warning displays cannot be presented regarding the presence/absence of printing sheets in the respective sheet feeding devices, and thereby improve the operability of a printing system. In a printing system including an image forming apparatus and a print controller, the image forming apparatus has a deck-type first sheet feeder, a tray-type second sheet feeder, and a sheet quantity notification unit for the sheet feeders, and the print controller has a display unit. The print controller displays a warning when there are no remaining printing sheets in the first sheet feeder, and does not display a warning when there are no remaining printing sheets in the second sheet feeder.

A system for detecting labels arranged on a support and spaced apart from one another by a spacing, the system including a transmitter part including a transmitter arranged to transmit a beam of ultrasonic waves towards the support which carries the labels, a receiver part, separated from the transmitter part, such that the support carrying the labels can pass along a plane located between the transmitter part and the receiver part, the transmitter part or the receiver part being arranged so that the beam of ultrasonic waves transmitted by the transmitter covers, on the support carrying the labels, a total surface area in which the surface area occupied by the spacing between two labels is greater than the surface area occupied by the labels.

A medium conveyance device includes: a first conveyance unit that applies a first conveyance force in a conveyance direction to a lowest medium among media on a medium stacker; a second conveyance unit disposed downstream in the conveyance direction of the first conveyance unit and that applies a second conveyance force in the conveyance direction to the medium being conveyed in the conveyance direction; a detector that detects that a rear end of the lowest medium receiving the first conveyance force passes through the first conveyance unit; and a controller that controls the first and second conveyance units. Upon determining that the rear end of the lowest medium receiving the first conveyance force passes through the first conveyance unit, the controller switches the first conveyance unit from a conveyance state of applying the first conveyance force to a non-conveyance state of not applying the first conveyance force.

A medium conveyance device includes: a first conveyance unit that applies a first conveyance force in a conveyance direction to a lowest medium among media on a medium stacker; a second conveyance unit disposed downstream in the conveyance direction of the first conveyance unit and that applies a second conveyance force in the conveyance direction to the medium being conveyed in the conveyance direction; a detector that detects that a rear end of the lowest medium receiving the first conveyance force passes through the first conveyance unit; and a controller that controls the first and second conveyance units. Upon determining that the rear end of the lowest medium receiving the first conveyance force passes through the first conveyance unit, the controller switches the first conveyance unit from a conveyance state of applying the first conveyance force to a non-conveyance state of not applying the first conveyance force.

The component supply device includes a body, a first carrier tape transporter, a second carrier tape transporter, and a controller. The body includes a tape transport path. The first carrier tape transporter transports a carrier tape to a component pickup position. The second carrier tape transporter transports the carrier tape to the first carrier tape transporter. The controller is configured to communicate with the component installation device and control the first carrier tape transporter and the second carrier tape transporter in one operation mode selected from a plurality of operation modes.

A system for detecting labels arranged on a support and spaced apart from one another by a spacing, the system including a transmitter part including a transmitter arranged to transmit a beam of ultrasonic waves towards the support which carries the labels, a receiver part, separated from the transmitter part, such that the support carrying the labels can pass along a plane located between the transmitter part and the receiver part, the transmitter part or the receiver part being arranged so that the beam of ultrasonic waves transmitted by the transmitter covers, on the support carrying the labels, a total surface area in which the surface area occupied by the spacing between two labels is greater than the surface area occupied by the labels.

A first actuator is detected at a first detection position by a detecting unit when no sheet is held on a feed tray, and is not detected at a first non-detection position by the detecting unit when the first actuator is in contact with a sheet held on the feed tray. A second actuator is detected at a second detection position by the detecting unit when the second actuator is in contact, at a predetermined position downstream of the first actuator in a conveying direction, with a sheet conveyed, and is not detected at a second non-detection position by the detecting unit when the second actuator is out of contact, at the predetermined position, with the sheet conveyed. A restricting member restricts the first actuator from moving from the first non-detection position to the first detection position when the second actuator is at the second detection position.

A first actuator is detected at a first detection position by a detecting unit when no sheet is held on a feed tray, and is not detected at a first non-detection position by the detecting unit when the first actuator is in contact with a sheet held on the feed tray. A second actuator is detected at a second detection position by the detecting unit when the second actuator is in contact, at a predetermined position downstream of the first actuator in a conveying direction, with a sheet conveyed, and is not detected at a second non-detection position by the detecting unit when the second actuator is out of contact, at the predetermined position, with the sheet conveyed. A restricting member restricts the first actuator from moving from the first non-detection position to the first detection position when the second actuator is at the second detection position.