| 摘要 |
<p>An erasure board with several writing fields (6), whereby each field is erased independently of the other fields during the separation of a writing layer (3, 4) from an underlayer (5). The underlayer is a bottom plate (5) which is divided into a number of tongues (7) corresponding to the number of writing fields (6). Between the bottom plate and the frame (1) is placed a writing layer which consists, for example, of waxed paper (4), over which is placed a translucent writing plate (3). By means of dividing pieces (2), the frame (1) divides the writing layer (3, 4) into a number of writing fields. The information noted down in the fields can be erased completely or partly by pressing down the tongue (7) under each of the fields. The board consists of simple parts moulded in plastic, the result being a very simple and cheap construction. The individual parts of the construction are assembled by merely placing them on top of one another in that sequence in which they enter into the construction.</p> |
