发明名称 |
SYSTEM FOR DETECTING HUMAN PRESENCE IN HAZARDOUS SITUATIONS |
摘要 |
The disclosure relates to a system for the detection of human presence in hazardous situations near moving machinery; appropriately shaped electrodes are placed in an area to be safeguarded and a radio-frequency signal of appropriate frequency and voltage is applied on the electrodes creating an alternating electric field around them. A bridge circuit is used to measure the capacitive impedance created by the electrodes and a dissipation factor is calculated from the real and imaginary parts of the impedance. If a foreign object is introduced into the electric field, the characteristics of the dielectric are modified creating a change of the value of the dissipation factor. The dissipation of energy in the high frequency region is much greater if this foreign object is a biological tissue as compared to other types of materials, such as conductors or insulators. Thus, the system detects human presence by noting the increase of the dissipation factor above a threshold value, and the movement of the appropriate machine part can then be stopped, thereby eliminating the danger of injury to the person. |
申请公布号 |
CA2095398(C) |
申请公布日期 |
2001.06.12 |
申请号 |
CA19932095398 |
申请日期 |
1993.05.03 |
申请人 |
I.R.S.S.T. INSTITUT DE RECHERCHE EN SANTE ET EN SECURITE DU TRAVAIL DU QUEBE |
发明人 |
GHOSH, KALYAN;BOSE, TAPAN K.;COURTEAU, RAYMOND;GIBELLO, PIERRE |
分类号 |
F16P3/14;G08B13/26;(IPC1-7):G08B13/24 |
主分类号 |
F16P3/14 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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