Calculator with keys which can selectively be disabled

Details Calculator with keys which can selectively be disabled Calculator with keys which can selectively be disabled

1994-12-22

1997-06-10

Mai, Tan V.

Boots, shoes, and leggings

G06F 300

Patent

active

056383088

ABSTRACT:
A portable, preferably pocket-sized electronic calculator includes provision for disabling the use of certain keys on its keyboard. By holding down a number key or certain of the function keys for a predetermined period of time such as two to four seconds, the user can disable the selected number or function. This allows the calculator to be used effectively in teaching factoring and various mathematical properties and leads the student to innovate in substituting different numbers and functions in solving problems in the student's own way. For discontinuing all key disabling a reset key preferably is provided.

REFERENCES:
patent: 4154007 (1979-05-01), Judd
patent: 4262337 (1981-04-01), Jones
patent: 4831569 (1989-05-01), Duriez
patent: 4836786 (1989-06-01), Wong
patent: 5020012 (1991-05-01), Stockberger et al.
patent: 5035502 (1991-07-01), Stokes

Affiliated with

Also associated with

Rating

Calculator with keys which can selectively be disabled does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Calculator with keys which can selectively be disabled, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Calculator with keys which can selectively be disabled will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-770382