Method and apparatus for determining halt of tape feed in a tape cartridge for a printer

Claim 2

Apparatus for use with a tape cartridge for a printer to determine halt of tape feed from a supply reel having a tape thereon to a take-up reel, said apparatus comprising first means on one of said reels for undergoing rotation therewith, second means fixed in position to face said first means to cooperate with said first means without mechanical contact therewith for producing electrical output pulses as said first means rotates with said one reel, third means coupled to said second means for determining halting of rotation of said one reel and consequent halting of tape feed upon cessation of said output pulses, locking means for locking said supply reel against rotation at the end of tape feed from the supply reel, and ratchet means coupled to said supply reel, said locking means being coupled to said ratchet means, said ratchet means including a ratchet wheel secured for common rotation with said supply reel and a pivotable pawl lever engaging the tape under tension during feed of the tape and including a pawl tooth engageable with said ratchet wheel, said locking means including a second tooth on said lever for engaging said ratchet wheel to lock the ratchet wheel against rotation when tension in the tape increases at the end of tape feed.

Claim 3

Apparatus for use with a tape cartridge for a printer to determine halt of tape feed from a supply reel having a tape thereon to a take-up reel, said apparatus comprising means including alternate reflective and non-reflective portions coupled to one of said reels for undergoing displacement as said one reel rotates and the tape is being fed, a fixed irradiation means facing said reflective and non-reflective portions for irradiating said reflective and non-reflective portions alternately as said one reel rotates, a fixed receiver means for receiving pulses of reflected radiation from said reflective portion as said one reel rotates, means coupled to said receiver means for determining whether said one reel is rotating or has stopped depending on the presence or absence of said pulses, said reflective and non-reflective portions being arranged as alternating radial bands on said one reel, said one reel being the supply reel, locking means for locking said supply reel against rotation at the end of tape feed from the supply reel, ratchet means coupled to said supply reel, said locking means being engaged with said ratchet means, said ratchet means including a ratchet wheel secured for common rotation with said supply reel and a pivotable pawl lever engaging the tape under tension during feed of the tape and including a pawl tooth engagable with said ratchet wheel, said locking means including a second tooth on said lever for engaging said ratchet wheel to lock the ratchet wheel against rotation when tension in the tape increases at the end of tape feed.

Claim 4

Apparatus for use with a tape cartridge for a printer to determine halt of tape feed from a supply reel having a tape thereon to a take-up reel, said apparatus comprising means including alternate reflective and non-reflective portions coupled to one of said reels for undergoing displacement as said one reel rotates and the tape is being fed, a fixed irradiation means facing said reflective and non-reflective portions for irradiating said reflective and non-reflective portions alternately as said one reel rotates, a fixed receiver means for receiving pulses of reflected radiation from said reflective portion as said one reel rotates, means coupled to said receiver means for determining whether said one reel is rotating or has stopped depending on the presence or absence of said pulses, said reflective and non-reflective portions being arranged as alternating radial bands on said one reel, said one reel being the supply reel, locking means for locking said supply reel against rotation at the end of tape feed from the supply reel, ratchet means coupled to said supply reel, said locking means being engaged with said ratchet means, said ratchet means including a ratchet wheel secured for common rotation with said supply reel and a pivotable pawl lever engaging the tape under tension during feed of the tape and including a pawl tooth engagable with said ratchet wheel, said locking means including a second tooth on said lever for engaging said ratchet wheel to lock the ratchet wheel against rotation when tension in the tape increases at the end of tape feed.

Claim 7

A method as claimed in claim 3 wherein the supply reel is locked against rotation at the end of tape feed from the supply reel.