Method and device for detecting multiple feed
AssigneeRiso Kagaku Corporation
InventorShinya Okada
Life of this patent
Estimating the term…
Abstract
A light emitting sensor emits light toward sheets carried along a carriage path and the quantity of light transmitted through each to the sheets is detected by a light receiving sensor. A predetermined sampling number of electric signals indicative of light quantity detected by the light receiving sensor is stored in a memory. A histogram of the light quantities stored in the memory is created. A light quantity corresponding to a maximum frequency for an underlying portion of the sheets is detected based on the created histogram. A multiple feed of the sheets is detected based on a variation in the light quantity of the maximum frequency for the underlying portion.
Claims8
A multiple feed detection device comprising:
- a sheet detector having a light emitting sensor and a light receiving sensor arranged in vicinity of a carriage path to detect quantity of light that has transmitted through a sheet;
- a memory which stores a predetermined sampling number of electric signals indicative of light quantity outputted from the sheet detector;
- and
- a processor which creates a histogram of the light quantity stored in said memory, obtains the light quantity corresponding to a maximum frequency for an underlying portion of sheets based on the created histogram, and detects a multiple feed of said sheets based on a variation in the light quantity of the maximum frequency.
A multiple feed detection method comprising the steps of:
- arranging a sheet detector having a light emitting sensor and a light receiving sensor in vicinity of a carriage path to detect quantity of light that has transmitted through a sheet;
- storing a predetermined sampling number of electric signals indicative of light quantity outputted from the sheet detector in a memory;
- creating a histogram of the light quantity stored in said memory;
- detecting the light quantity corresponding to a maximum frequency for an underlying portion of sheets based on the created histogram;
- and
- detecting a multiple feed of said sheets based on a variation in the light quantity of the maximum frequency.
Dependencies are inferred from the claim text.