Automatic magnetic fingerprint brush

Abstract

The invention relates to an automatic magnetic fingerprint brush. The brush includes a handle and a brush head internally provided with a permanent magnet and a connecting base; the permanent magnet is fixed to the lower portion of the connecting base; the inner side wall of the brush head is evenly provided with two track grooves, the circumferential surface of the connecting base is provided with sliding blocks corresponding to the two track grooves in a one-to-one mode, and the sliding blocks are connected to the track grooves in a sliding mode; a spring is installed between the bottom of the brush head and the connecting base; the sliding blocks are clamped to lower locating points of the track grooves, and the brush head is used for attracting magnetic powder; the sliding blocks detach from the lower locating points and are reset to high locating points under the effect of the spring, and then the brush head releases the magnetic powder; the bottom of the handle is fixedly provided with a connecting shaft made of ferromagnetic metal; a first sleeve hole is formed in the portion corresponding to the permanent magnet and above the connecting base, and a connecting shaft is sleeved in the first sleeve hole, so that under the effect of the magnetic attraction force of the permanent magnet, the connection between the brush head and the handle is achieved. The automatic magneticfingerprint brush is small, exquisite, light and portable in structure, convenient to use and capable of reducing load of surveyors and improving the survey efficiency.

Description

technical field [0001] The invention relates to the field of fingerprint brushes for criminal investigation, in particular to an automatic magnetic fingerprint brush. Background technique [0002] Collecting fingerprints or palmprints is an indispensable work in on-site investigation, which can provide important clues for the detection of cases. Have it extracted by a technician. Existing fingerprint brushes include chinchilla hair fingerprint brushes, magnetic fingerprint brushes, feather fingerprint brushes, powder storage fingerprint brushes, and fiber fingerprint brushes. Magnetic fingerprint brushes have the characteristics of easy operation and good fingerprint extraction effects, so they are widely used by criminal investigation agencies. application. [0003] The applicant previously applied for an invention patent with the publication number CN106175786 (denoted as patent 1) and the patent name of an automatic fingerprint display brush in 2016, including the handl...

AI Technical Summary

Problems solved by technology

However, (1), the fingerprint display brush of Patent 1 has a large volume and a certain weight, which increases the burden on the staff, which is not conducive to fast and flexible scanning of the scene and reduces work efficiency

(2) The structure of the fingerprint display brush in Patent 1 is complicated, and cumbersome power lines need to be laid out, which increases the difficulty of assembly, increases the skill requirements for workers, reduces production efficiency, and greatly increases processing costs

(3) The fingerprint display brush of Patent 1 requires a large number of electronic components and housing blocks, which increases the cost of raw materials and reduces the profit of the enterprise, which is not conducive to widespread application

(4) When patent 1 uses an electromagnet to absorb magnetic powder, the electromagnet needs to be kept energized and consumes a lot of power, which has a certain impact on the overall working time and is not conducive to long-term operation

The magnet stays inside the plastic headgear for a long time, and some magnetic powder or other impurities remain on the plastic headgear. It is very troublesome to clean up, and it will seriously affect the integrity and accuracy of the brush display. Therefore, the plastic headgear needs to be replaced frequently

The plastic headgear of the above-mentioned patent is tightly connected by the collar and then slipped on the central shaft, that is, the plastic headgear and the collar are connected without gaps, so it is difficult to separate the collar from the plastic headgear, and the forced separation by external force will directly affect the The collar is damaged, and the collar, etc. also need to be replaced, which is very troublesome to operate

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