| 摘要 |
<p>PURPOSE:To prevent the deterioration of a position detecting function of a light-sensing element as a photosensor due to paper powder or the like by covering the top part of the light-sensing element with a transparent cover having a large curvature and by constructing the same so that a paper sheet wipes the top part of the cover. CONSTITUTION:In a bank note conveyance unit 1, a light-emitting element 3 directed downward and a light-sensing element 4 directed upward which detect the pass or position of a bank note 2 are disposed on the opposite sides of a conveyance line A-A of the bank note 2. The bank note 2 intercepts a light emitted by the element 3 and sensed by the element 4 and it can be detected thereby that the bank note 2 passes or that it is positioned. While the element 4 is held in a sensor holder 5, the top part of the element 4 is covered with a transparent cover 6 having a projecting surface of a large curvature and the top part of the cover 6 is made to project slightly from the conveyance line A-A. Since the bank note 2 wipes the top part of the transparent cover 6 at all times according to this constitution, neither paper powder nor dust is accumulated on the surface of the cover 6. Since the top part of the transparent cover 6 has the large curvature, in addition, it does not check the conveyance of the bank note 2, and skew and paper clogging caused thereby can be prevented.</p> |
