Patent EA-000425-B1 (EA)
Title: Device and process for separating a sheet article from a stack
Inventor: LEUTHOLD KARL
IPC: B65H1/24
Filed: 1996-11-22
Abstract: 1. A device for separating a sheet article from a stack, such as bank notes, the stack lies on a moveable pressure plate (20) with which the stack (10) is led to a removal device (30) the latter lies on a moveable pressure plate (20) with which the stack (10) is led to a removal device (30), which separates a sheet from upper sheets of the stack, characterized in that a density sensor (50, 60, 70, 80, 81) is provided which determines the density of the stack (10) continuously during separation of sheets at least in the region of the removal device (30), the density acts as a gauge of the surface pressure of the sheets on the removal device (30) a control device (21) is provided which controls the distance (D) between the pressure plate (20) and the removal device (30) in relation to the determined density in such a manner that during separation the stack (10) is pressed at a constant surface pressure against the removal device (30). 2. The device of Claim 1, characterized in that the density sensor (50, 60) comprises at least the following elements: an air nozzle (50) blowing air between sheets of the stack (10), causing the sheets to vibrate and a microphone (60) for measuring noise level, caused by sheets vibration. 3. The device of Claim 1, characterized in that the density sensor (50, 70) comprises at least the following elements: an air nozzle (50) blowing an air between sheets of the stack (10), arranged on one of sides of the stack (10) an air pressure sensor (70) for measuring the air pressure, passed through the stack (10) on its opposite side. 4. The device of Claim 1, characterized in that the density sensor (80, 81) comprises at least the following elements: a light source (80) lighting one of the pack (10) sides; and a light receiver (81), arranged on the opposite side from the pack (10) for measuring the light, passed through it. 5. The device of Claim 4, characterized in that the light source (80) is a light diode matrix. 6. The device of Claim 4, characterized in that the light source (80) is a photo diode matrix or a matrix of a charge-coupled device (CCD). 7. The device of Claim 1, characterized in that the density sensor (80, 81) comprises at least the following element: CCD-chamber (90), permitting to obtain the edges of sheets in the pack (10). 8. A method of separating a sheet article from a stack, such as bank notes, the stack lies on a moveable pressure plate (20) with which the stack (10) is led to a removal device (30) the latter lies on a moveable pressure plate (20) with which the stack (10) is led to a removal device (30), which separates a sheet from upper sheets of the stack, characterized in that: in the process of separation sheets from the pack (10) the density of the stack (10) is continuously determined at least in the region of the removal device (30) the density acts as a gauge of the surface pressure of the sheets on the removal device (30). the distance (D) between the pressure plate (20) and the removal device (30) is controlled in relation to the determined density in such a manner that during separation the stack (10) is pressed at a constant surface pressure against the removal device (30). 9. The method of Claim 8, characterized in that to determine density of the pack (10) at least the following steps to be undertaken: blowing air between sheets of the stack (10), causing the sheets to vibrate measuring noise level, caused by sheets vibration determining the pack (10) density by the noise level. 10. The method of Claim 8, characterized in that to determine density of the pack (10) at least the following steps to be undertaken: blowing air between sheets of the stack (10), causing the sheets to vibrate measuring the air pressure, passed through the stack (10), and determining the pack (10) density by the measured pressure. 11. The method of Claim 8, characterized in that to determine density of the pack (10) at least the following steps to be undertaken: lighting one of the pack (10) sides measuring of light, passed through the pack (10) and determining the pack (10) density by intensity of the measured light. 12. The method of Claim 8, characterized in that to determine density of the pack (10) at least the following steps to be undertaken: obtaining the image of the sheets edges in the pack (10). calculating by the obtained image of the sheets edges in the pack (10). determining the pack (10) density by a number of the sheet edges.