The paper thickness measuring device
The utility model relates to a kind of thick device of using of measurement paper in optical character reader (OCR), intelligent character reader.
At present, the paper thickness measuring device of using in known optical character reader (OCR), the intelligent character reader has two kinds.
A kind of is to utilize optical transmission, promptly place photoemission cell and receiving tube respectively in the both sides up and down of release, judge release thickness by measuring the light intensity that sees through release, this mode is subjected to the influence of release quality, color and the mark of card own easily, and precision and reliability are not high.
Another kind is a physical construction, transfer at paper feed wheel a pinch roller being set, by the leverage that is connected with the paper feed wheel with the thick amplification of paper, measurement again.Because the paper feed wheel is direct and leverage links, again rubber wheels that adopt more, after wearing and tearing, the position of lever can change, and causes to measure error to occur; The vibration that produces when in addition, the paper feed wheel rotates also can produce harmful effect to the result who measures; This device can't be as an independent component debug, must debug together being installed on the reading machine back and main frame, very is unfavorable for being unfavorable for use increasing work efficiency.
Summary of the invention
Poor in order to overcome the paper thickness measuring device measuring accuracy of using in existing optical character reader (OCR), the intelligent character reader, the deficiency that can not debug separately, the purpose of this utility model provides a kind of paper thickness measuring device, this device can not only high precision to measure paper thick, and can do as a whole the debugging easily, after finishing, debugging can be installed on the reading machine at any time.
To achieve these goals, the utility model by the following technical solutions: a kind of paper thickness measuring device comprises housing, paper feed tray, leverage, optocoupler and voltage table, and described paper feed tray, leverage, optocoupler are fixed in the housing, forms an integral body; Be provided with a wear-resisting paper feed tray in the paper feed position of housing bottom, one end of leverage is provided with rolling bearing as pinch roller, pinch roller is pressed in the paper feed tray top, the other end of leverage is provided with a light barrier, the light barrier edge is positioned at the centre position of optocoupler, the output terminal of the optocoupler voltage table outer with being arranged on housing is connected, and its output voltage is read by voltage table, thereby obtains the thickness of release.
The end that the leverage of described paper thickness measuring device is provided with light barrier is connected with a spring, and spring is fixed on the housing, can prevent since the not enough leverage that causes of pinch roller deadweight can not return phenomenon.
The beneficial effects of the utility model are, because what link with leverage be pinch roller, so can overcome the wearing and tearing of former paper feed wheel, the measurement of avoiding the vibrations of paper feed wheel to cause is inaccurate, makes it in quite long serviceable life, and assurance is to the accurate measurement of release thickness; Because each parts of this device are installed in the same housing, it can independently be debugged, the convenient installation.
Description of drawings
Fig. 1 is the utility model paper thickness measuring device structural representation.
Fig. 2 is the utility model paper thickness measuring device Sensor section circuit diagram
As Fig. 1, shown in Figure 2, a kind of paper thickness measuring device comprises housing 7, paper feed tray 6, leverage 1, optocoupler 5 and voltage table 8, and described paper feed tray 6, leverage 1, optocoupler 5 are fixed in the housing 7, form an integral body; Be provided with a wear-resisting paper feed tray 6 in the paper feed position of housing 7 bottoms, one end of leverage 1 is provided with rolling bearing as pinch roller, pinch roller 2 is pressed in the paper feed tray top, the other end of leverage 1 is provided with a light barrier 4, light barrier 4 edges are positioned at the centre position of optocoupler 5, the output terminal of optocoupler 5 voltage table 8 outer with being arranged on housing 7 is connected, and its output voltage is read by voltage table 8, thereby obtains the thickness of release.
The end that the leverage 1 of described paper thickness measuring device is provided with light barrier 4 is connected with a spring 3, and spring 3 is fixed on the housing 7, can prevent since the not enough leverage that causes of pinch roller deadweight can not return phenomenon.
As shown in Figure 1 and Figure 2, V is a supply voltage, and by resistance R 0, rheostat R1 is the optocoupler power supply, and the output voltage of optocoupler 5 is U0, and the output terminal of optocoupler 5 is connected with voltage table 8.When light barrier 4 was positioned at the core of optocoupler 5, the light accepting part branch of optocoupler 5 was in the amplification region of triode, and adjust R1 this moment, with output voltage V
0Be made as set-point.When the position of light barrier 4 changes, output voltage V 0 also can respective change.The release of different-thickness can make light barrier 4 produce different amount of movements, thereby produces different output voltage V
0, measure output voltage V by voltage table 8
0, thick according to the paper of given voltage correspondence, can draw release thickness.
Rolling bearing 2 and light barrier 4 are installed in the two ends of lever 1 respectively, and the lever arm length that is provided with light barrier 4 one sides is greater than the lever arm length that is provided with rolling bearing 2 one sides.When release passed through, pinch roller was lifted slightly, and under the effect of spring 3, pinch roller is pressed on the carriage 6, and the displacement of pinch roller is exaggerated by lever, and light barrier 4 just blocks the part light path of optocoupler 5.At this moment, because variation has taken place light path, optocoupler changes on its output voltage values through photoelectric effect, thereby records the thickness of release.
Because the outer ring of rolling bearing has good smooth finish and hardness, can not think and can be worn and torn by release.Because rolling bearing self precision is higher, complete simultaneously and paper feed kinematic train breaks away from simultaneously, and therefore just passive rotation under the drive of release can not produce harmful vibration.