| 摘要 |
<p>PURPOSE: To improve usage value and secure high reliability in operation by radiating radiation to a transport route of a thready element and by detecting and evaluating variation of a signal generated due to receiving of passed radiation. CONSTITUTION: Radiation generated from infrared light emitting diode 3 penetrates through an opening 9' and a glass tube 10, irradiates the inside of the glass tube 10, and thus almost whole of passage region of thread and others is irradiated. A visual field of the facing light receiving element 5, in assist of a lens 7, covers cross section of thread supply in surface regions of the light emitting diode and the light receiving element. Therefore, the light receiving element 5 receives radiation transmitted from the light emitting element 3 and passing through whole thread passing cross section, the strength of the received light there varies by certain amount depending on different diffusion and refraction by the thread and deviation of the axial position of the moving thread. Such signal variation is evaluated in an evaluation circuit, and stopping or absence of threads can be detected in high reliability.</p> |
