| 摘要 |
<p>The invention relates to an abacus which can be used as a didactic means in kindergarten, in primary school as well as at home, for teaching the first mathematic notions and abilities referring to numbers and operations with numbers. According to the invention, the abacus comprises a bedframe (1) lengthwise partitioned into some compartments separated by some side walls, wherethrough four axles (2) pass, within the said compartments, on the said axles, there being some rollers (3 and 4), either simple or provided with a driving collar, on which, at the top part of the bedframe (1) there are some running tapes (5, 11 and 12) printed with the images of countable objects, while, at the bottom part of the bedframe (1) there are some running tapes (6) printed with graphic signs, making up an assembly over which a cover (7) is placed, this cover being provided with some recesses (10) through which a part of the collar of the driving rollers (4) comes out and with two transparent windows (8 and 9) with the possibility of manually driving the printed tapes (5, 11 and 12) so as to suitably match, upon use, what the image window (8) and the graphic sign window (9) display, depending on the proposed activity.</p> |
