CN221366244U - Paper flattening mechanism and printed matter on-line detection system - Google Patents

Abstract

The utility model discloses a paper flattening mechanism, which comprises: a gas supply device; the flow equalizing cavity is connected with the air supply device; and the plurality of nozzles are communicated with the uniform flow cavity and are used for blowing out fan-shaped gas, and the plurality of nozzles are arranged side by side along the same direction, so that the fan surfaces of the fan-shaped gas are connected with each other to form a straight line on the surface of the substrate to be sprayed. Through the structural design of the nozzles and the arrangement design of the nozzles, the fan-shaped air flow formed by the nozzles is positioned on the same plane, the air flow presents a linear fan-shaped injection angle, a linear air knife is formed to act on the paper, the paper is flattened to the greatest extent, and the possibility of paper wrinkling and curling is reduced.

Description

Paper flattening mechanism and printed matter on-line detection system

Technical Field

The disclosure relates to the technical field of printing equipment, in particular to a paper flattening device.

Background

The traditional offset printing machine is widely used in China, and relates to various industries such as food, medicines, cosmetics, cigarette packs, electronic packages and the like, and the China has become a huge country of the printing industry which is a famous and true country.

In the prior art, the blowing physical flattening is usually adopted, and the roller is circular and has curvature, so that the paper is always tightly attached to the roller in the drawing process, and thus, high requirements are placed on the magnitude and stability of wind pressure. At present, in order to ensure enough air pressure, the traditional mode adopts a high-power vortex air pump to perform pressure holding air supply, and along with voltage fluctuation and extremely easy aging (temperature rise) of the air pump, the output air flow has a movement condition, so that energy is wasted, the actual flattening effect also fluctuates greatly, and the air pump can be continuously used in occasions with low requirements.

The thickness of the printing paper can be regulated by the air quantity by the same equipment, and the common mode is realized by controlling the rotating speed of a motor by adopting a frequency converter. When the gram weight of the paper is large, the air flow sprayed by the common nozzle has enough area and striking force, so that the flattening requirement can be basically met; when the gram weight of the paper is smaller, especially the paper with the gram weight lower than 70 g, the nozzles cannot be arranged in a high-density way, break points and disturbance exist between the ejected air flows, the paper is extremely easy to fold, a large number of images are deformed and misreported, and the system use is affected.

Disclosure of utility model

In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides a paper flattening mechanism that can be used for flattening a paper in a roll printing process. The paper flattening mechanism includes:

a gas supply device;

the flow equalizing cavity is connected with the air supply device; and

The nozzles are communicated with the uniform flow cavity and used for blowing out fan-shaped gas, and the nozzles are arranged side by side along the same direction, so that the fan surfaces of the fan-shaped gas are connected with each other to form a straight line on the surface of a substrate to be sprayed.

Further, the fan angle of the fan-shaped gas is 20-110 degrees.

Further, the fan angle of the fan-shaped gas is 60-90 degrees.

Further, the nozzle has an inlet end, an outlet end, and a fluid passageway in communication with the inlet end and the outlet end;

The fluid channel comprises a drainage section and a diversion section from the inlet end to the outlet end, the flow area of the diversion section is gradually reduced, the nozzle is provided with a diversion trench at the outlet end, and the diversion trench extends to the diversion section and forms a fluid outlet so as to blow out the fan-shaped gas.

Further, the diversion trench is arranged on the outer wall of the outlet end in a penetrating manner in the arrangement direction of the nozzles.

Further, the guiding groove comprises a first guiding surface and a second guiding surface, an included angle formed by the first guiding surface and the second guiding surface is in a V shape, and the guiding groove extends to the guiding section to form a fluid outlet in a surrounding mode.

Further, the flow guiding section forms a sphere or conical surface extending towards the outlet end on the bottom surface of the nozzle.

Further, the air supply device is communicated with the uniform flow cavity through a pipeline; the pipeline comprises a main pipeline and more than two branches communicated with the main pipeline, and the branches are respectively communicated with the uniform flow cavity.

Further, the air supply device is a controllable air supply device.

Further, the air supply device is an uncontrollable air supply device, and a controllable valve and an adjustable valve are sequentially arranged on a pipeline connected with the uncontrollable air supply device and the flow equalizing cavity.

Further, the cross section of the flow equalizing cavity is round or square.

An on-line inspection system for printed matter mounted in a peripheral space of an impression cylinder of a printing press, comprising:

A flattening mechanism according to any one of the preceding claims, for flattening a sheet on an impression cylinder; and

And the image acquisition device is used for acquiring the surface image of the paper positioned at the flattening treatment part of the flattening mechanism.

Further, the plurality of nozzles are arranged in a direction parallel to the axis of the impression cylinder.

Further, the blowing direction of the flattening mechanism is reverse to the rotation direction of the impression cylinder.

Further, the collection line of the image collection device intersects with the blowing direction of the nozzle to imprint

The same point on the surface of the roller forms an included angle alpha, and the included angle alpha meets the following conditions: alpha is more than or equal to 10 degrees and less than or equal to 70 degrees.

Further, the included angle α satisfies: alpha is more than or equal to 20 degrees and less than or equal to 50 degrees.

Compared with the prior art, the technical scheme provided by the utility model has the following advantages:

The nozzles in the flattening mechanism provided by the disclosure can form fan-shaped air flows, the fan-shaped air flows formed by the nozzles are located on the same plane through structural design of the nozzles and arrangement design of the nozzles, and a plurality of fan-shaped air flows form continuous straight lines on a substrate to be ejected, such as an impression cylinder. The arrangement direction of the diversion trenches penetrating through the side wall is consistent with the arrangement direction of the plurality of nozzles, so that the diversion trenches of the plurality of nozzles are on the same straight line, and the straight line formed by the fan-shaped airflow on the impression cylinder is ensured to be parallel to the axis of the impression cylinder. When the high-pressure air flow is ejected from the nozzle, the air flow presents a linear fan-shaped ejection angle, so that a linear air knife is formed to act on the paper, and the paper is flattened to the greatest extent. Because the straight line is continuous and the paper is reversely blown at a large angle, the paper can have uniform acting force on the paper backwards, and the possibility of wrinkling and curling of the paper is reduced.

Drawings

The accompanying drawings are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate the utility model and together with the embodiments of the utility model, serve to explain the utility model. In the drawings:

FIG. 1 is a schematic illustration of a nozzle emitting a flow of air;

FIG. 2 is a schematic view of a fan angle formed by the air flow emitted from the nozzle;

FIG. 3 is a schematic view of a structure of a flattening mechanism according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a flow equalizing cavity and nozzle of a flattening mechanism according to an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a flow equalizing cavity and nozzle of a flattening mechanism according to an embodiment of the present disclosure;

FIG. 6 is a front view of a nozzle according to an embodiment of the present disclosure;

FIG. 7 is a cross-sectional view of the nozzle of FIG. 5 taken along the direction A-A;

FIG. 8 is a cross-sectional view of the nozzle of FIG. 5 taken along the direction B-B;

FIG. 9 is a perspective cross-sectional view of a nozzle according to an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of an online detection system for printed matter according to an embodiment of the present disclosure;

fig. 11 is a partial enlarged view of the structure shown in fig. 9.

Wherein:

1-an air supply device;

2-flow equalizing cavity;

21-a first air inlet;

22-a second air inlet;

23-a first air inlet;

24-a second air inlet;

25-a third air inlet;

26-fourth air inlet;

3-nozzles;

30-fan-shaped gas;

31-an inlet end;

32-an outlet end;

33-fluid channel;

331-a drainage section;

332-a diversion section;

34-diversion trenches;

341-a first flow guiding surface;

342-a second flow guiding surface;

35-a fluid outlet;

4-a pipeline;

41-a first branch;

42-a second branch;

45-pressure reducing valve;

46 solenoid valve;

5-acquisition lines;

6-an acquisition part;

7-paper;

8-a light source;

9-an impression cylinder;

10-flattening mechanism;

11-an image acquisition device;

111-a scaffold;

112-acquisition means;

12-blowing direction;

13-housing.

Detailed Description

Hereinafter, only certain exemplary embodiments are briefly described. As will be recognized by those of skill in the pertinent art, the described embodiments may be modified in various different ways without departing from the spirit or scope of the present utility model. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more of the described features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be fixedly connected, detachably connected, or integrally connected, and may be mechanically connected, electrically connected, or may communicate with each other, for example; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present utility model, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is less level than the second feature.

The following disclosure provides many different embodiments, or examples, for implementing different features of the utility model. In order to simplify the present disclosure, components and arrangements of specific examples are described below. They are, of course, merely examples and are not intended to limit the utility model. Furthermore, the present utility model may repeat reference numerals and/or letters in the various examples, which are for the purpose of brevity and clarity, and which do not themselves indicate the relationship between the various embodiments and/or arrangements discussed. In addition, the present utility model provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

The preferred embodiments of the present utility model will be described below with reference to the accompanying drawings, it being understood that the preferred embodiments described herein are for illustration and explanation of the present utility model only, and are not intended to limit the present utility model.

Example 1:

In this embodiment 1, as a specific preferred embodiment of the present utility model, a flattening mechanism 10 is shown which can be used for flattening the paper 7 in real time when the paper 7 is subjected to rolling motion in an environment such as a roll printing process. As shown in fig. 1 to 3, the flattening mechanism 10 includes a gas supply device 1, a uniform flow chamber 2, and a plurality of nozzles 3. The flow equalizing cavity 2 is connected with the air supply device 1; the plurality of nozzles 3 are communicated with the flow equalizing cavity 2 for blowing out the fan-shaped gas 30, and the plurality of nozzles 3 are arranged side by side in the same direction so that the fan surfaces of the plurality of fan-shaped gas 30 are connected to each other to form a straight line on the surface of the substrate to be sprayed.

The fan angle of the fan-shaped gas 30 and the distance between the adjacent nozzles 3 are combined to connect the fan-shaped gas 30 ejected from the nozzles 3 to each other so as to form a continuous straight line with a certain thickness on the surface of the substrate to be ejected. Theoretically, the same point where the collection line 5 intersects the blowing direction 12 of the nozzle 3 on the surface of the impression cylinder, which we call the collection point, is the maximum in-line distance formed by the nozzle 3 on the surface of the substrate, assuming that the distance from the nozzle 3 to the collection point is r and the fan angle of the fan-shaped gas 30 is θHowever, as the collection point is directed toward the edge of the straight line, the force acting on the surface of the substrate is gradually reduced, so that the distance between adjacent nozzles 3 is smaller thanSo that the fan-shaped gas 30 can form a continuous "straight" shape on the substrate surface. When the fan angle of the fan-shaped gas 30 is large, the distance between adjacent nozzles 3 may be relatively large; when the fan angle of the fan-shaped gas 30 is small, the distance between the adjacent nozzles 3 is relatively small, so that the fan-shaped gas 30 ejected from the nozzles 3 is connected to each other to form a continuous straight line having a certain thickness on the surface of the substrate to be ejected. When the fan angle of the fan-shaped gas 30 is large and the distance between the adjacent nozzles 3 is relatively small, the force acting on the surface of the substrate can be made more uniform, the possibility of wrinkling and curling of the paper 7 can be reduced, and the flattening effect can be made better. In actual production, according to the actual use situation, the distance between the fan angle of the fan-shaped gas 30 and the adjacent nozzles 3 is finally set so as to achieve the effect of flattening the paper 7.

In some alternative embodiments, the fan angle of the fan gas 30 may be 20-110. In actual operation, the fan angle is 60-90 degrees, and the effect is optimal, as shown in fig. 2. The cross section of the flow equalizing cavity 2 can be round or square. It is well known to those skilled in the art that the shape of the flow equalizing cavity 2 may be other shapes with elliptical, triangular, etc. cross-sections, which may be equally substituted by those skilled in the art based on the present disclosure.

The following describes the components and their connection relationships in detail.

Air supply device 1

According to the specific paper weight of 7 g, the utility model can select centralized air supply or independent air supply of an industrial air compressor: when the 7 g weight of the paper is less than 150g, the concentrated air supply can be selected preferentially, the requirements on the pressure and the flow of the air source are low, and the self-use high-pressure air in a common factory can completely meet the requirements; when the weight of 7 g of paper is greater than 150g, paper jam is mostly caused, the requirement on air sources is high at the moment, and if a factory cannot provide corresponding air sources, a screw air compressor with enough power can be selected for independent air supply. The air source mode can be flexibly selected according to the use situation of the equipment. The reasonable selection of the two air supply modes can jointly solve the air supply problem of 40g-400g paper 7, has low noise and high energy efficiency ratio, works along with the working of the paper flattening mechanism 10 of the printer, and reduces energy waste.

The air supply device 1 is classified into a controllable type and an uncontrollable type. The controllable gas supply device is a control system on the gas supply device 1, and can detect the pressure and the gas outlet quantity of the gas. The uncontrollable air supply device is connected with the pipeline of the uniform flow cavity 2, and is sequentially provided with a controllable valve and an adjustable valve, for example, the controllable valve is an electromagnetic valve 46, the adjustable valve is a pressure reducing valve 45 for controlling air supply, and the purpose of energy saving is achieved by introducing the control of the electromagnetic valve 46; by introducing control of the pressure reducing valve 45, the optimal flattening effect can be achieved by corresponding adjustment according to the type of the product.

The air supply device 1 is communicated with the uniform flow cavity 2 through a pipeline 4; the pipeline 4 comprises a main pipeline 40, and two or more branches communicated with the main pipeline 40 are respectively communicated with the uniform flow cavity 2.

Flow equalizing cavity 2

The flow equalizing chamber 2 is used for providing gas with relatively uniform density and pressure to each nozzle 3. The pipeline 4 comprises a main pipeline 40, and two or more branches communicated with the main pipeline 40 are respectively communicated with the uniform flow cavity 2. The gas enters each nozzle 3 from the uniform flow cavity 2 and is sprayed out. In actual operation, the number of branches can be two or more, and the width of the paper 7 which is flattened as required, the size of the uniform flow cavity and the gas pressure are determined. The flow equalizing cavity can be provided with a plurality of air inlets which are opened according to actual demands and are communicated with the branches. For example, 10 air inlets may be provided on the flow equalizing cavity, but in practice 4 may be opened and the other 6 closed. At this time, the 4 branches are communicated with the opened 4 air inlets. Therefore, the device can be effectively and flexibly adjusted according to the condition of site construction operation.

As a preferred embodiment, as shown in fig. 4, the pipeline 4 includes a main pipeline 40, four branches that are communicated with the main pipeline, the current equalizing cavity 2 is communicated with the four branches, the current equalizing cavity 2 is provided with a first air inlet 23, a second air inlet 24, a third air inlet 25 and a fourth air inlet 26, the four branches are respectively communicated with the first air inlet 23, the second air inlet 24, the third air inlet 25 and the fourth air inlet 26, each branch and the current equalizing cavity 2 can be communicated through a connecting piece, and can also be integrally formed, in this embodiment, the current equalizing cavity 2 adopts a square pipe. When gas flows to the first air inlet 23, the second air inlet 24, the third air inlet 25 and the fourth air inlet 26 respectively through four branches, the gas enters the uniform flow cavity 2 through the air inlets, fan-shaped gas 30 is sprayed out through the nozzles 3, the arrangement of multiple branches enables the gas pressure distribution in the uniform flow cavity 2 to be more uniform, and the possibility that the flattening effect is poor due to the fact that the pressure in the uniform flow cavity 2 is reduced after the branches are fewer and the gas is sprayed out through the nozzles 3 adjacent to the air inlets, the gas pressure sprayed out from the nozzles 3 which are relatively far away from the air inlets is reduced, so that uniform acting force cannot be formed on the surface of a substrate is reduced; meanwhile, due to the arrangement of multiple branches, the pressure in the flow equalizing cavity 2 is more uniform, the fan surface range of the fan-shaped gas 30 sprayed out by the nozzle 3 is larger, so that the fan-shaped gas 30 is more beneficial to interconnection, a continuous straight line is formed on the surface of a substrate, and the flattening effect is better.

As an alternative embodiment, as shown in fig. 5, the equalizing cavity 2 is a circular tube, and the equalizing cavity 2 is communicated with two branches.

As an alternative embodiment, as shown in fig. 3, the pipeline 4 includes a main pipeline 40, a first branch pipeline 41 and a second branch pipeline 42 which are communicated with the main pipeline, and the first branch pipeline 41 and the second branch pipeline 42 are respectively communicated with two ends of the flow equalizing cavity 2. The two ends of the flow equalizing cavity 2 are provided with a first air inlet 21 and a second air inlet 22; the first branch 41 and the second branch 42 are respectively communicated with the first air inlet 21 and the second air inlet 22 of the blowing cavity. The first branch 41 and the second branch 42 and the uniform flow cavity 2 can be communicated through a connecting piece, and can also be integrally formed. The air supply device 1 is used as an air source to simultaneously convey air to the two ends of the uniform flow cavity 2 through the pipeline 4, so that air inflow at the two ends of the uniform flow cavity 2 is realized, the air flows can be uniformly distributed on each nozzle 3, the pressure in each nozzle 3 is ensured to be consistent, the force of the air sprayed out of the nozzles 3 on the surface of a substrate is the same, and the possibility of wrinkling and curling of paper 7 is reduced.

In actual operation, the gas is output from the gas supply device 1, flows through the pipe 4, passes through the solenoid valve 46 and the pressure reducing valve 45 in this order, and is split between the first branch 41 and the second branch 42. The air of the first branch 41 flows to the first air inlet 21, the air of the second branch 42 flows to the second air inlet 22, and the first branch 41 and the second branch 42 are respectively communicated with the first air inlet 21 and the second air inlet 22 of the blowing cavity. In general, the areas of the inner sections of the first air inlet 21 and the second air inlet 22 are the same, and the areas of the inner sections of the first branch 41 and the second branch 42 are the same, so that the pressure or the flow rate of the air inlet at two ends of the uniform flow cavity 2 are the same, the pressure in each nozzle 3 is further ensured to be consistent, the force of the air sprayed by the nozzle 3 on the impression cylinder 9 is the same, and the possibility of wrinkling and curling of the paper 7 is further reduced.

Nozzle 3

As shown in fig. 6 to 9, the nozzle 3 has an inlet end 31, an outlet end 32, and a fluid passage 33 communicating between the inlet end 31 and the outlet end 32. From the inlet end 31 to the outlet end 32, the fluid channel 33 comprises a flow guiding section 331 and a flow guiding section 332. The flow area of the deflector segment 332 decreases gradually. For example, the deflector segment 332 forms a spherical or conical surface on the bottom surface of the nozzle 3 extending toward the outlet end 32. The nozzle 3 is provided with a flow guide groove 34 at the outlet end 32. The diversion trench 34 is arranged on the outer wall of the outlet end in a penetrating manner in the arrangement direction of the plurality of nozzles 3. Specifically, the diversion trench 34 includes a first diversion surface 341 and a second diversion surface 342, where the first diversion surface 341 and the second diversion surface 342 may form a V-shaped included angle. The diversion trench 34 extends to the diversion segment 332, and the top of the diversion segment is opened to form an outlet, namely, the fluid outlet 35 is formed by surrounding the diversion trench 34.

The gas uniformly enters each nozzle from the flow equalizing cavity, enters the fluid channel 33 from the inlet end 31, sequentially passes through the diversion section 331 and the diversion section 332, and finally is sprayed out from the fluid outlet 35. At this time, the ejected gas has a fan-shaped structure having a certain thickness, which is referred to as fan-shaped gas 30 (see fig. 1) in the present utility model, under the guidance of the two diversion surfaces 341, 342 of the diversion trench 34. Referring to fig. 10-11, taking cylinder printing of the paper 7 as an example, each fan-shaped gas 30 falls on the impression cylinder 9 to form a "one" character with a certain thickness, and by adjusting the distance between the nozzle 3 and the impression cylinder 9 and the arrangement density of the nozzles 3, the "one" character is overlapped and connected, and finally a linear air knife is formed to act on the paper 7, so that the paper 7 is flattened to the greatest extent. Since the straight line is continuous and the traveling direction of the sheet 7 is reversely blown at a large angle, the sheet 7 is prevented from being wrinkled and curled. When the centralized air supply is used, all devices belong to maintenance-free devices and can be normally used for a long time; when using the air compressor, the maintenance requirement of the air compressor needs to be followed, and the replacement of the internal engine oil is performed about half a year so that the equipment works normally. Therefore, under normal conditions, the machine operator can ensure the detection capability of the whole online detection system by properly adjusting the output of the air supply pressure according to the gram weight of the printed product.

Example 2:

This embodiment shows an on-line inspection system for printed matter, as shown in fig. 10-11, installed in the peripheral space of the impression cylinder 9 of a printing press, comprising:

the flattening mechanism 10 described above for flattening the sheet 7 on the impression cylinder 9; and

And the image acquisition device 11 is used for acquiring the surface image of the paper 7 at the flattening treatment part of the flattening mechanism 10.

Wherein the direction of arrangement of the plurality of nozzles 3 is parallel to the axial direction of the impression cylinder 9.

The image acquisition device 11 comprises a bracket 111 and an acquisition device 112 hinged on the bracket 111, and the image acquisition device 11 is arranged outside a shell 13 of the printer so as to ensure that an acquisition line 5 of the acquisition device 112 can fall into a flattening position of the impression cylinder 9. The image acquisition device 11 can be mounted on the housing 13 of the printing machine, or can be mounted in other ways, so as to ensure that the acquisition line 5 can fall into the flattened portion of the impression cylinder 9. In some specific embodiments, the support 111 is fixedly connected to the housing 13 of the printer, as shown in fig. 10, the collection device 112 may rotate on the support 111, and the collection device 112 may be rotated, so that the collection device 112 may adapt to the positions of impression cylinders of different specifications, and during the adjustment, the collection line 5 of the collection device 112 is continuously changed to determine that the collection line 5 intersects the blowing direction 12 of the nozzle 3 at the same point on the surface of the impression cylinder, and forms an included angle α.

In some specific embodiments, the capture device 112 is a camera.

In some specific embodiments, the collection line 5 of the image collection device 11 is directed toward the impression cylinder 9 and the collection portion 6 is formed on the impression cylinder 9, the blowing direction 12 of the nozzle 3 intersects the collection line 5 at the same point on the surface of the impression cylinder 9, and this point falls in the collection portion 6. When the impression cylinder 9 rotates, the blowing direction 12 of the flattening mechanism 10 is opposite to the rotation direction of the impression cylinder 9, so that the paper 7 on the impression cylinder is attached to the impression cylinder 9 and flattened, and the image of the flattened part is acquired by the acquisition device 112 for recording, so that the flattening condition is detected online.

In order to ensure the proper operation of the image capturing device 11, the image capturing device 11 further comprises a light source 8, and the light source 8 projects light onto the capturing section 6 on the impression cylinder 9, thereby illuminating the image in the capturing section 6.

As shown in fig. 11, the collection line 5 intersects the blowing direction 12 of the nozzle 3 at the same point on the surface of the impression cylinder 9, and forms an angle α satisfying: alpha is more than or equal to 10 degrees and less than or equal to 70 degrees; preferably, 20 DEG.ltoreq.alpha.ltoreq.50 deg. The range of the included angle enables the acting force of the air flow on the paper 7 to be larger, reduces the possibility of wrinkling and curling of the paper 7, and enables the flattening effect of the paper 7 to be better.

Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present utility model, and the present utility model is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present utility model has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (15)

1. A paper flattening mechanism, comprising:

a gas supply device (1);

the uniform flow cavity (2), the uniform flow cavity (2) is connected with the air supply device (1); and

A plurality of nozzles (3), wherein the nozzles (3) are communicated with the uniform flow cavity (2) and are used for blowing out fan-shaped gas (30), and the nozzles (3) are arranged side by side along the same direction, so that the fan surfaces of the fan-shaped gas (30) are connected with each other to form a straight line on the surface of a substrate to be sprayed;

The nozzle (3) has an inlet end (31), an outlet end (32) and a fluid passage (33) communicating between the inlet end (31) and the outlet end (32);

From the inlet end (31) to the outlet end (32), the fluid channel (33) comprises a drainage section (331) and a diversion section (332), the overflow area of the diversion section (332) is gradually reduced, the nozzle (3) is provided with a diversion trench (34) at the outlet end (32), and the diversion trench (34) extends to the diversion section (332) and forms a fluid outlet (35) so as to blow out the fan-shaped gas (30).

2. A paper flattening mechanism according to claim 1, wherein the fan angle of the fan-shaped gas (30) is 20-110 °.

3. A paper flattening mechanism according to claim 2, wherein the fan angle of the fan-shaped gas (30) is 60-90 °.

4. A paper flattening mechanism according to claim 1, wherein the diversion trench (34) is provided on the outer wall of the outlet end (32) penetrating in the arrangement direction of the plurality of nozzles (3).

5. The paper flattening mechanism according to claim 4, wherein the diversion trench (34) comprises a first diversion surface (341) and a second diversion surface (342), an included angle formed by the first diversion surface (341) and the second diversion surface (342) is V-shaped, and the diversion trench (34) extends to the diversion section (332) and forms a fluid outlet (35) together.

6. A paper flattening mechanism according to claim 1, wherein the deflector section (332) forms a sphere or cone on the bottom surface of the nozzle (3) extending towards the outlet end (32).

7. A paper flattening mechanism according to claim 1, characterized in that the air supply device (1) is in communication with the flow equalizing chamber (2) via a pipe (4); the pipeline (4) comprises a main pipeline (40) and more than two branches communicated with the main pipeline, and the branches are respectively communicated with the uniform flow cavity (2).

8. A paper flattening mechanism according to claim 1, characterized in that the air supply (1) is a controllable air supply.

9. The paper flattening mechanism according to claim 1, wherein the air supply device (1) is an uncontrollable air supply device, and a controllable valve and an adjustable valve are sequentially arranged on a pipeline connected with the flow equalizing cavity (2) by the uncontrollable air supply device.

10. A paper flattening mechanism according to claim 1, characterized in that the cross section of the flow equalizing cavity (2) is circular or square.

11. An on-line inspection system for printed matter, mounted in the peripheral space of the impression cylinder (9) of a printing machine, characterized in that it comprises:

The flattening mechanism (10) of any of the claims 1-10, for flattening a sheet (7) on an impression cylinder (9); and

And the image acquisition device (11) is used for acquiring the surface image of the paper (7) positioned at the flattening treatment part of the flattening mechanism (10).

12. The printed matter on-line detection system according to claim 11, characterized in that the direction of arrangement of the plurality of nozzles (3) is parallel to the axis of the impression cylinder (9).

13. An online detection system of printed matter according to claim 11, characterized in that the blowing direction (12) of the flattening mechanism (10) is counter to the rotation direction of the impression cylinder (9).

14. The online detection system of printed matter according to claim 11, characterized in that the collection line (5) of the image collection device (11) intersects the blowing direction (12) of the nozzle (3) at the same point on the surface of the impression cylinder (9) and forms an angle α, which satisfies: alpha is more than or equal to 10 degrees and less than or equal to 70 degrees.

15. The printed matter on-line detection system of claim 14, wherein the included angle α satisfies: alpha is more than or equal to 20 degrees and less than or equal to 50 degrees.