1. Field of the Invention
The present invention relates to a label printer. More specifically it relates to an RFID reader/writer and a media roll with a rewritable RFID tag that can keep track of the number of remaining labels on the roll.
2. Description of Related Art
Printable labels generally come in a roll. The roll of label media has a finite number of labels on it. To reduce or eliminate downtime (of both staff and machinery) and to not waste any labels, it is important to know the number of labels remaining on the roll. An accurate count of the number of remaining labels allows a user to prepare for changing the label roll at the appropriate time. Prior art printers have a counter that keeps track of the number of labels printed.
Some user applications require that the label media be changed before the roll is depleted. This may occur when a number of first labels need to be printed and then a number of second labels need to be printed where the two labels require different label media. Prior art label printers cannot accurately determine the number of labels remaining on a media roll that has been changed prior to being depleted. Prior art label printers estimate the number of remaining media by measuring the roll diameter, as labels are used the diameter of the media roll decreases. However, this method does not provide an accurate count of the number of remaining labels. Alternatively, a user can manually enter label count into the printer each time the label roll is changed. This requires that the user maintain records on the number of remaining labels and manually enter this information into the printer each time a roll of label media is replaced.
There is a need for an automated system that keeps track of the number of labels remaining even when media rolls are switched out before the roll is depleted.
The inventive device is the label printer with an RFID reader/writer and a media roll with a rewritable RFID tag. The printer “odometer” keeps track of the number of labels remaining on a media roll. The printer sends a signal to the rewritable RFID tag on the printer media with information about the remaining labels.
A label printer embedded RFID tag reader/writer and the media roll with a rewritable RFID tag affixed to the media are used to keep a running tally of the number of remaining labels on the roll and record the tally onto the RFID tag.
When a roll of media is manufactured an RFID tag can be affixed to the media, generally on the media hub. The RFID tag contains information about the total number of labels on the roll. When the media is loaded onto a printer, the printer queries the roll to determine the number of labels remaining. When each label is printed, the printer's RFID writer decrements the label count on the rolls and writes this information to the RFID tag. This feature allows the printer to always report the correct number of remaining labels on the roll, even if the printer is loaded with a partially full roll. When a partially used roll of media is removed from the printer the RFID tag “remembers” the number of labels remaining. When the roll is again loaded onto the printer, the printer RFID reader interrogates the RFID tag for the number of labels remaining.
Alternatively, in the case of a receipt printer, the length of the receipt media is initially written onto the RFID tag in the media hub. As receipts are printed the printer keep keeps track of the remaining length of the roll. After each receipt is printed, the length of the printed receipt is subtracted from the stored value on the RFID tag and a new value is stored.
The inventive device is the label printer 1 with an RFID reader/writer 2 and a media roll 3 with a rewritable RFID tag 4. The printer “odometer” keeps track of the number of labels remaining on a media roll 3. The printer 1 sends a signal to the rewritable RFID tag 4 on the printer media 3 with information about the remaining labels.
A label printer 1 embedded RFID tag reader/writer 2 and the media roll 3 with a rewritable RFID tag 4 affixed to the media 3 are used to keep a running tally of the number of remaining labels on the roll and record the tally onto the RFID tag 4.
When a roll 3 of media is manufactured an RFID tag 4 can be affixed to the media, generally on the media hub. The RFID tag 4 contains information about the total number of labels on the roll 3. When the media 3 is loaded onto a printer 1, the printer 1 queries the RFID tag 4 on the roll 3 to determine the number of labels remaining. When each label is printed, the printer 1 decrements the label count on the roll 3. The RFID reader/writer 2 then writes this information to the RFID tag 4. This feature allows the printer 1 to always report the correct number of remaining labels on the roll 3, even if the printer 1 is loaded with a partially full roll 3. When a partially used roll 3 of media is removed from the printer 1 the RFID tag 4 “remembers” the number of labels remaining. When the roll 3 is again loaded onto the printer 1, the printer RFID reader 2 interrogates the RFID tag 4 for the number of labels remaining. The RFID writer 2 can write to the tag 4 each time a label is printed, each time a set number of labels have printed, each time a specified period of time has elapsed, at a specified period after a print job, at some other regular interval or based on some other criteria. The regular interval may be based on print time, elapsed time, number or amount of media printed or some other criteria.
Alternatively, in the case of a receipt printer 1, the length of the receipt media is initially written onto the RFID tag 4 in the media hub. As receipts are printed the printer 1 keeps track of the remaining length of the roll 3. After each receipt is printed, the length of the printed receipt is subtracted from the stored value on the RFID tag 4 and a new value is stored.