Automatic powder supply trace detection equipment and powder supply method for extracting fingerprints by powder method at crime scene

Abstract

The invention relates to a trace detection tool in the field of public security criminal investigation, in particular to an automatic powder trace detection device and a powder supply method for extracting fingerprints by powder method at a crime scene. The front cover and the rear cover and the base are respectively installed on the bracket , the air pump and the powder bottle are respectively housed in the inner space formed by the back cover and the bracket, the base and the bracket, and are installed on the bracket respectively, the spray tube is placed in the front cover, one end is hinged with the bracket, and the other end is installed with a fluffy brush; The fluidized bed is located below the powder contained in the powder bottle. The lower end of the powder bottle is connected to the air pump, and the upper end is connected to the spray barrel through the airflow conduit; the pressurized gas provided by the air pump is "boiling" the powder through the fluidized bed. The mixed gas with powder is sprayed onto the trace inspection working surface through the nozzle, the flowing powder touches the trace and is adsorbed on the surface of the trace to form a clear image. , the image after brushing is clearer and more stable.

Description

technical field [0001] The invention relates to a trace detection tool in the field of public security criminal investigation, in particular to an automatic powder trace inspection device and a powder supply method for extracting fingerprints by powder method at a crime scene. Background technique [0002] Currently, the most common method used to image and analyze crime scene fingerprints is called powder visualization. This is often seen in movies or television, where investigators brush fine powder on fingerprints and stick scotch tape to get the shape and traces of the powder (actually traces of fingerprints); The information is stored on tape so it can be easily taken back to the lab for in-depth analysis. If fingerprints remain on the surface of non-absorbent items such as metal, plastic, glass, tiles, etc., you can use the powder method to extract fingerprints, dip a little powder with a soft brush, and flick the brush handle to make the powder evenly scattered on th...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the problem that harmful dust diffuses in the air and pollutes the environment and harms the bodies of police officers handling the case, the purpose of the present invention is to provide an automatic powder supply trace inspection device and powder supply method for extracting fingerprints by powder method at the crime scene

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