A paper feed sensor for a miniature printer

Abstract

The invention discloses a paper feeding sensor of a miniprinter. The sensor comprises an installation frame connected to a printer engine, a touch arm, and a support provided with a photoelectric sensor, wherein a rotary shaft perpendicular to the touch arm is arranged at one end of the touch arm, the touch arm is hinged to one end of the installation frame through the rotary shaft, the rotary shaft is sleeved with a torsion spring, one of the two positioning ends of the torsion spring is clamped to the touch arm, and the other positioning end of the torsion spring is clamped to the installation frame; the support is installed on the installation frame and provided with a light sensing channel, a limiting block is arranged on the lower side of the touch arm, a limiting surface is arranged at the lower end of the installation frame, the limiting block is matched with the limiting surface to enable the lower side face of the touch arm to be as high as the upper edge of the light sensing channel, and a sensing part protruding out of the installation frame is arranged on the upper side face of the touch arm. The photoelectric sensor is combined with a mechanical blocking structure, reaction speed is high, required printing paper pressure is small, paper feeding is smoother, paper jamming is reduced, and the paper feeding sensor is suitable for printing paper in dark color.

Description

technical field [0001] The invention relates to a paper feeding sensor for a micro printer. Background technique [0002] Micro printers are widely used in various industries, such as instrumentation, supermarkets, convenience stores, postal services, banks, tobacco monopoly, utility meter reading, mobile police systems, mobile government systems, etc. A paper feed sensor is provided in the micro printer to monitor whether there is printing paper in the printer, and the traditional paper feed sensor is a mechanical sensor or a photoelectric sensor. [0003] The mechanical sensor uses the swing of the hook handle to drive the spring contact switch in the sensor to disconnect or combine, and realizes the detection of printing paper by judging whether the circuit is disconnected or conducted, and the spring contact switch of the mechanical sensor has With a certain amount of resilience, when using some thinner or softer printing paper, the printing paper may not completely pre...

AI Technical Summary

Problems solved by technology

When encountering printing paper with a darker color (such as black), part of the light emitted by the transmitting end may be absorbed by the printing paper, and the intensity of reflected light received by the receiving end is insufficient, resulting in detection failure

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