Fingerprint display device

Abstract

The utility model provides a fingerprint appearing device, belongs to fingerprint identification technical field, fingerprint appearing device includes body, storage box, blowing subassembly, be equipped with the accommodation chamber in the body, be equipped with acceleration chamber and the powder outlet channel in the accommodation chamber, be equipped with the spiral runner in the acceleration chamber, the powder outlet channel with the innermost circle of spiral runner is communicated, and the powder outlet channel with the innermost circle of spiral runner is equipped with the air blowing subassembly. The powder storage box is arranged in the containing cavity and provided with a discharging port, the discharging port communicates with the outermost ring of the spiral flow channel, the air blowing assembly is arranged in the containing cavity and provided with an air inlet end and an air outlet end, the air inlet end communicates with the atmospheric environment, the air inlet end communicates with the outermost ring of the spiral flow channel, and the air blowing assembly is used for accelerating and pressurizing air sucked by the air inlet end. And the powder is discharged into the accelerating cavity from the air outlet end, so that the powder in the accelerating cavity is discharged from the powder outlet channel under the action of the spirally accelerated air. According to the fingerprint developing device, developing powder can be uniformly scattered on fingerprints, and the fingerprint developing quality is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of fingerprint recognition, and particularly relates to a fingerprint developing device. Background Technique

[0002] Fingerprint developing technology is a series of methods used to develop latent fingerprints on various surfaces. These technologies are crucial for fields such as forensic medicine, criminal investigation science, and security inspections, as they can help identify criminal suspects or recover key evidence at the crime scene. Common fingerprint developing technologies include iodine fuming method, silver nitrate method, powder method, and suspension method.

[0003] Among them, the principle of the powder method is through the mechanical adsorption and electrostatic adsorption of fingerprint substances and powder. When the color-developing powder acts on the surface of the bearing object, the colorless fingerprint lines are made visible due to the adhesion of the powder. In practice, when implementing the powder method, generally a soft brush is dipped in a little powder, and the brush handle is gently flicked to evenly scatter the powder on the fingerprint, and then the excess powder is shaken off or gently brushed off with the tip of the brush, and the colorless fingerprint can become a colored fingerprint.

[0004] However, it is very difficult to control the powder scattering force in this way, resulting in uneven powder scattering. Specifically, if too much powder is scattered, the fingerprint will be smeared by the brush; if too little powder is scattered, the clarity of the fingerprint display is not ideal enough. Content of the Utility Model

[0005] Based on this, the purpose of the utility model is to provide a fingerprint developing device, aiming to be able to evenly scatter the color-developing powder on the fingerprint and improve the fingerprint developing quality.

[0006] To achieve the above purpose, the utility model provides a fingerprint developing device, which includes a body, a powder storage box, and a blowing component. An accommodation cavity is provided inside the body, an acceleration cavity and a powder outlet channel are provided inside the accommodation cavity, a spiral flow channel is provided inside the acceleration cavity, the powder outlet channel is communicated with the innermost circle of the spiral flow channel, the powder storage box is arranged inside the accommodation cavity and has a material outlet, the material outlet is communicated with the outermost circle of the spiral flow channel, the blowing component is arranged inside the accommodation cavity and has an air inlet end and an air outlet end, the air inlet end is communicated with the atmospheric environment, the air inlet end is communicated with the outermost circle of the spiral flow channel, and the blowing component is used to accelerate and pressurize the air inhaled from the air inlet end and discharge it into the acceleration cavity from the air outlet end, so that the powder in the acceleration cavity is discharged from the powder outlet channel under the action of the air accelerated by the spiral.

[0007] The beneficial effects of the utility model include at least: by setting up a powder storage box, it is convenient for long-term use, and at the same time, a blowing component and a spiral flow channel are set, so that under the action of the airflow blown into the spiral flow channel by the blowing component, the color-developing powder that falls from the powder storage box to the outermost circle of the spiral flow channel is blown away, and accelerates along the spiral flow channel to the innermost circle of the spiral flow channel, and finally the powder with uniform distribution and a certain initial velocity can be discharged from the powder outlet channel, and under the action of the color-developing powder, the latent fingerprints on various surfaces can be displayed with high quality.

[0008] In addition, the fingerprint display device according to the present invention may also have the following additional technical features:

[0009] Furthermore, the blowing assembly includes a turbine pump and a nozzle. The turbine pump has an inlet pipe and an outlet pipe. The inlet pipe is connected to the atmospheric environment. There are multiple nozzles that surround and penetrate the side wall of the acceleration chamber. One end of the nozzle outside the acceleration chamber is connected to the outlet pipe.

[0010] Furthermore, the included angle between the spraying direction of the nozzle and the tangent line of the spiral flow channel at the location of the nozzle does not exceed 45 degrees.

[0011] Furthermore, the air blowing assembly also includes an air-permeable dryer, which is connected to the end of the inlet pipe to filter and dry the inhaled air.

[0012] Furthermore, the breathable dryer includes a shell, a cover, and a breathable seal. An air duct connected to the inlet pipe is provided through the shell, and the air duct is filled with a desiccant. The cover is provided on the shell, and a waterproof breathable membrane is provided on the cover. The waterproof breathable membrane covers the opening of the air duct away from the inlet pipe side. The breathable seal is provided on the shell, and covers the opening of the air duct close to the inlet pipe side.

[0013] Furthermore, the discharge port is provided with a switch valve.

[0014] Furthermore, the powder storage box is also provided with a feeding port.

[0015] Furthermore, the main body is also provided with an opening and closing device to open and close the powder outlet channel.

[0016] Furthermore, a sliding hole is provided on the main body, a circular sliding groove is provided in the powder discharge channel, the opening and closing device includes a fixed baffle and a rotating baffle, the periphery of the fixed baffle is fixedly arranged in the powder discharge channel, the first discharge hole is evenly arranged in an array on the fixed baffle, the periphery of the rotating baffle is slid in the circular sliding groove, and the rotating baffle and the fixed baffle are arranged side by side, a shift block is provided on the rotating baffle, and the shift block protrudes from the outer surface of the main body after passing through the sliding hole, and the second discharge hole is evenly arranged on the rotating baffle, wherein when the rotating baffle rotates, the second discharge hole can be aligned with and staggered with the first discharge hole.

[0017] Furthermore, a sealing cover is detachably provided at one end of the powder outlet channel away from the acceleration chamber. Brief Description of the Drawings

[0018] Figure 1 It is a cross-sectional view taken along the cutting plane of the powder storage tank in the present utility model;

[0019] Figure 2 It is a cross-sectional view taken along the cutting plane of the turbine pump in the present utility model;

[0020] Figure 3 It is a schematic structural diagram of the turbine pump in the embodiment of the present utility model;

[0021] Figure 4 It is a schematic structural diagram of the acceleration chamber in the embodiment of the present utility model;

[0022] Figure 5 It is a schematic structural diagram of the air-permeable dryer in the embodiment of the present utility model;

[0023] Figure 6 It is a schematic structural diagram of the opening and closing device in the embodiment of the present utility model;

[0024] Figure 7 It is a schematic structural diagram of the powder outlet channel in the embodiment of the present utility model;

[0025] Description of the Main Element Symbols:

[0026] Body 100, accommodation chamber 110, acceleration chamber 111, powder outlet channel 112, guide plate 113, spiral flow channel 114, mounting hole 115, circular sliding groove 116, sliding hole 120, powder storage tank 200, discharge port 210, on-off valve 211, feed port 220, turbine pump 310, inlet pipe 311, outlet pipe 312, nozzle 320, air-permeable dryer 330, housing 331, cover 332, air-permeable seal 333, air channel 334, waterproof and breathable membrane 335, opening and closing device 400, fixed baffle 410, first discharge hole 411, rotating baffle 420, second discharge hole 421, dial block 422, seal cover 500;

[0027] The following specific embodiments will further illustrate the present utility model in conjunction with the above-mentioned drawings. Specific Embodiments

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0029] It should be noted that all the directional indications in the embodiments of the present application are only used to explain the relative positional relationship, movement conditions, etc. between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0030] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0031] In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0032] Referring to Figures 1 to 7 , a fingerprint developing device provided by the present utility model includes a main body 100, a powder storage box 200, and a blowing assembly. Specifically, an accommodation cavity 110 is provided in the main body 100. An acceleration cavity 111 and a powder outlet channel 112 are provided in the accommodation cavity 110. A spiral flow channel 114 is formed in the acceleration cavity 111 through a spiral guide plate 113. The powder outlet channel 112 communicates with the innermost circle of the spiral flow channel 114. The powder storage box 200 is provided in the accommodation cavity 110 and is located above the acceleration cavity 111. The powder storage box 200 has a material outlet 210. The material outlet 210 communicates with the outermost circle of the spiral flow channel 114. During use, the developing powder stored in the powder storage box 200 falls from the material outlet 210 to the outermost circle of the spiral flow channel 114 under the action of gravity. The blowing assembly is provided in the accommodation cavity 110 and has an air inlet end and an air outlet end. The air inlet end communicates with the atmospheric environment, and the air inlet end communicates with the outermost circle of the spiral flow channel 114. During use, the blowing assembly accelerates and pressurizes the air inhaled from the air inlet end and discharges it into the acceleration cavity 111 from the air outlet end. At this time, the developing powder that has fallen to the outermost circle of the spiral flow channel 114 is accelerated and flows from the outermost circle of the spiral flow channel 114 to the innermost circle of the spiral flow channel 114 under the push of the air flow, and finally is discharged through the powder outlet channel 112. Among them, the quantity of the developing powder discharged through the powder outlet channel 112 is controlled by adjusting the speed and pressure of the air discharged into the acceleration cavity 111 by the blowing assembly. Preferably, in order to expand the spraying coverage area of the developing powder discharged through the powder outlet channel 112, the powder outlet channel 112 is conical, and the large port of the powder outlet channel 112 faces outward.

[0033] In this embodiment, the air flow introduced into the spiral channel 114 evenly disperses the color developing powder that has fallen to the outermost circle of the spiral channel 114, and accelerates it through the air flow, and finally discharges the evenly distributed powder from the powder discharge channel 112. When it is necessary to adjust the quantity of the powder discharged from the powder discharge channel 112, only the speed and pressure of the air discharged by the air blowing assembly into the acceleration chamber 111 need to be adjusted.

[0034] In some alternative embodiments, as Figures 2 to 4 shown, the air blowing assembly includes a turbine pump 310 and a nozzle 320. The turbine pump 310 has an inlet pipe 311 and an outlet pipe 312. The inlet pipe 311 is communicated with the atmospheric environment. In this way, the turbine pump 310 can suck air from the atmospheric environment, accelerate and pressurize it through centrifugal force. There are multiple nozzles 20 and they surround the side wall of the acceleration chamber 111. Specifically, mounting holes 115 are axially arranged on the side wall of the acceleration chamber 111, and the nozzles 320 are hermetically installed in the mounting holes 115. One end of the nozzle 320 located outside the acceleration chamber 111 is connected to the outlet pipe 312, and one end of the nozzle 320 located inside the acceleration chamber 111 sprays air. When it is necessary to adjust the quantity of the powder discharged from the powder discharge channel 112, only the rotation speed of the turbine pump 310 needs to be adjusted.

[0035] In order to improve the efficiency of the air flow driving the movement of the color developing powder, in some alternative embodiments, as Figure 4 shown, the included angle between the spraying direction of the nozzle 320 and the tangent of the spiral channel 114 at the position where the nozzle 320 is located does not exceed 45 degrees. In this way, the velocity component of the air flow sprayed by the nozzle 320 along the tangent direction is larger than the velocity component perpendicular to the tangent direction of the air flow, which is more conducive to increasing the flow velocity of the color developing powder in the spiral channel 114.

[0036] In some alternative embodiments, as Figure 2 、 Figure 5 shown, the air blowing assembly further includes a breathable dryer 330. The breathable dryer 330 is connected to the end of the inlet pipe 311 to filter and dry the inhaled air, preventing water vapor and impurities in the atmosphere from entering the acceleration chamber 111 and mixing with the color developing powder, causing the color developing powder to agglomerate and reducing the quality of the color developing powder.

[0037] In some alternative embodiments, as Figure 2 、 Figure 5As shown, the breathable dryer 330 includes a housing 331, a cover 332, and a breathable seal 333. The housing 331 is provided with an air passage 334 connected to the inlet pipe 311, and the air passage 334 is integrally connected, and the air passage 334 is filled with a desiccant. The cover 332 is provided on the housing 331, and a waterproof breathable membrane 335 is provided on the cover 332. The waterproof breathable membrane 335 covers the opening of the air passage 334 away from the inlet pipe 311. The breathable seal 333 is fixed on the housing 331, and the breathable seal 333 covers the opening of the air passage 334 close to the inlet pipe 311. Optionally, the waterproof breathable membrane 335 can be a breathable film of a polymer such as polyethylene (PE), polypropylene (PP), polyester (PET), etc., and the breathable seal 333 can be a non-woven fabric having both good waterproof performance and good breathability. Since the desiccant filled in the air duct 334 will have reduced performance or become ineffective after being used for a period of time, it often needs to be replaced. Preferably, the cover 332 is detachably provided on the shell 331, and the desiccant filled in the air duct 334 can be quickly replaced by removing the cover 332.

[0038] In some optional embodiments, such as Figure 1 As shown, the discharge port 210 is provided with a switch valve 211. By controlling the on and off of the switch valve 211, the discharge of the color-developing powder in the powder storage box 200 can be controlled. Specifically, after air is sprayed into the spiral flow channel 114 through the blowing assembly, the switch valve 211 is controlled to open, and the color-developing powder in the powder storage box 200 falls to the outermost circle of the spiral flow channel 114 and is fully dispersed by the airflow, and finally discharged from the powder outlet channel 112 under the action of the airflow.

[0039] In order to facilitate the replenishment of color powder into the powder storage box 200, in some optional embodiments, such as Figure 1 , Figure 2 As shown, the powder storage box 200 is also provided with a feed port 220 .

[0040] In some optional embodiments, such as Figure 6 , Figure 7As shown, the main body 100 is also provided with an opening and closing device 400, and the powder outlet channel 112 can be opened and closed by controlling the opening and closing of the opening and closing device 400. When the discharge port 210 is not provided with a switch valve 211, or when the blowing component is not working, the residual color-developing powder in the acceleration chamber 111 and / or the powder outlet channel 112 leaks out, causing waste and pollution. Specifically, a sliding hole 120 is provided on the main body 100, and a circular slide groove 116 is provided in the powder outlet channel 112. The opening and closing device 400 includes a fixed baffle 410 and a rotating baffle 420. During assembly, the periphery of the fixed baffle 410 is fixedly installed in the powder outlet channel 112. In order to discharge powder, a first discharge hole 411 is evenly arranged in an array on the fixed baffle 410, and the periphery of the rotating baffle 420 is embedded in the circular slide groove 116, so that the rotating baffle 420 can rotate in the circular slide groove 116. At the same time, in order to realize the opening and closing of the powder outlet channel 112. The function is to fit one end face of the rotating baffle 420 with one end face of the fixed baffle 410, and to evenly arrange the second discharge holes 421 on the rotating baffle 420. When the rotating baffle 420 is rotated, the second discharge holes 421 can be completely aligned with and completely staggered from the first discharge holes 411. When they are completely aligned, the color powder in the powder discharge channel 112 is discharged through the second discharge holes 421 and the first discharge holes 411, while when they are completely staggered, the color powder in the powder discharge channel 112 cannot be discharged through the second discharge holes 421 and the first discharge holes 411. In order to facilitate the rotation of the rotating baffle 420 during use, a shifting block 422 is provided on the rotating baffle 420. The shifting block 422 passes through the sliding hole 120 and protrudes from the outer surface of the body 100. When in use, force is applied to the shifting block 422.

[0041] In order to prevent water vapor from entering the device from the powder outlet channel 112 when not in use, in some optional embodiments, such as Figure 6 As shown, a sealing cover 500 is detachably provided at one end of the powder outlet channel 112 away from the acceleration chamber 111 , and the sealing cover 500 is removed when in use and installed when not in use. Optionally, the sealing cover 500 can be threadedly connected to the body 100 .

[0042] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] In the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present application.

[0044] In addition, in the present application, the descriptions such as "first", "second", etc. are only for descriptive purposes, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the fact that those skilled in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0045] In the description of the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "beneath" and "under" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0046] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0047] Although the preferred embodiments of the present application have been described, additional changes and modifications can be made to these embodiments by those of ordinary skill in the art once they learn of the basic creative concepts. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications that fall within the scope of the present application.

[0048] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims

1. A fingerprint visualization device, characterized in that, The fingerprint display device comprises: A body, wherein a receiving chamber is provided in the body, an acceleration chamber and a powder outlet channel are provided in the receiving chamber, a spiral flow channel is provided in the acceleration chamber, and the powder outlet channel is connected to the innermost circle of the spiral flow channel; A powder storage box is disposed in the accommodating cavity and has a discharge port, wherein the discharge port is connected to the outermost circle of the spiral flow channel; An air blowing assembly is arranged in the accommodating cavity and has an air inlet end and an air outlet end, the air inlet end is connected to the atmospheric environment, and the air inlet end is connected to the outermost circle of the spiral flow channel. The air blowing assembly is used to accelerate and pressurize the air sucked in by the air inlet end, and discharge it into the acceleration cavity from the air outlet end, so that the powder in the acceleration cavity is discharged from the powder outlet channel after being acted on by the spiral accelerated air.

2. The fingerprint display device according to claim 1, wherein The blowing assembly comprises: A turbo pump having an inlet pipe and an outlet pipe, wherein the inlet pipe is connected to the atmosphere; A plurality of nozzles are provided and surround and penetrate the side wall of the acceleration chamber. One end of the nozzle located outside the acceleration chamber is connected to the outlet pipe.

3. The fingerprint display device according to claim 2, characterized in that, The included angle between the spray direction of the nozzle and the tangent line of the spiral flow channel at the location of the nozzle does not exceed 45 degrees.

4. The fingerprint display device according to claim 2, wherein, The air blowing assembly further comprises an air permeable dryer connected to the end of the inlet pipe to filter and dry the inhaled air.

5. The fingerprint visualization device according to claim 4, characterized in that, The air-permeable dryer comprises: A shell, wherein an air passage communicating with the inlet pipe is provided through the shell, and the air passage is filled with a desiccant; A sealing cover is arranged on the housing, the sealing cover is provided with a waterproof and breathable membrane, and the waterproof and breathable membrane covers the opening of the airway away from the inlet pipe side; A breathable seal is arranged on the shell and covers the opening of the air passage close to the inlet pipe.

6. The fingerprint visualization device according to claim 1, wherein The discharge port is provided with a switch valve.

7. The fingerprint visualization device according to claim 1 or 6, characterized in that, The powder storage box is also provided with a feeding port.

8. The fingerprint visualization device according to claim 1, characterized in that, The main body is also provided with an opening and closing device to open and close the powder outlet channel.

9. The fingerprint display device according to claim 8, wherein The body is provided with a sliding hole, the powder outlet channel is provided with a circular sliding groove, and the opening and closing device comprises: A fixed baffle, the periphery of which is fixedly arranged in the powder outlet passage, and the fixed baffle is provided with first outlet holes in a uniform array; A rotating baffle, the periphery of which is slidably arranged in the circular slide groove, and the rotating baffle is arranged side by side with the fixed baffle, a shift block is arranged on the rotating baffle, and the shift block protrudes from the outer surface of the body after passing through the slide hole, and a second discharge hole is evenly arranged on the rotating baffle; When the rotating baffle rotates, the second discharge hole can be aligned with and staggered from the first discharge hole.

10. The fingerprint display device according to claim 9, characterized in that, A sealing cover is detachably provided at one end of the powder outlet channel away from the acceleration chamber.

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