CN219015983U

CN219015983U - Surface density measuring device

Info

Publication number: CN219015983U
Application number: CN202222466248.XU
Authority: CN
Inventors: 陈维刚; 张敬东; 真志辉; 展冰洋; 王强军; 晏亮杰; 吴谦
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-09-16
Filing date: 2022-09-16
Publication date: 2023-05-12
Anticipated expiration: 2032-09-16
Also published as: WO2024055774A1

Abstract

The embodiment of the application provides an area density measuring equipment, can cool down the air around the heating source in the area density measuring equipment, prevent that the temperature from rising and arousing ray intensity variation to area density measurement accuracy has been improved. The surface density measuring device comprises a ray emitter, a ray receiver and a thermal management mechanism; the ray emitter and the ray receiver are oppositely arranged to form a detection space; the ray emitter is used for emitting rays to the sheet-shaped detected object entering the detection space; the ray receiver is used for receiving the rays transmitted through the measured object so as to measure the surface density of the measured object; the thermal management mechanism is arranged outside an inlet of the detection space and is used for transmitting air flow between the detected object and the ray receiver.

Description

Surface density measuring device

Technical Field

The present application relates to the field of machinery, and in particular to an areal density measurement device.

Background

The lithium battery which is one of new energy sources has been gradually replaced the traditional lead-acid, nickel-hydrogen and nickel-cadmium batteries because of higher specific energy and environmental protection and no pollution of materials, and becomes the most important energy storage element in the twenty-first century. The positive and negative pole pieces are the most important components of the lithium battery, and the quality of the positive and negative pole pieces directly influences the actual use effect of the whole battery and even the life safety of users, so that the detection and control of the manufacturing quality of the pole pieces, particularly the gram weight (i.e. the surface density) of the material in unit area, are particularly important.

The lithium electrode positive and negative pole piece surface density measuring instrument can measure the surface density of the pole piece according to the ray intensity before and after penetrating the pole piece. When the surface density measuring instrument operates for a long time, the temperature in the instrument can be gradually increased, so that the air density is changed, the ray intensity is changed, and the surface density measuring precision is affected. Therefore, how to reduce the temperature in an areal density meter is a problem to be solved.

Disclosure of Invention

The embodiment of the application provides an area density measuring device, which can accelerate the air flow of the surface of a radiation receiver, namely, the temperature of the air around a heating source in the area density measuring device is reduced, and the change of the radiation intensity caused by the temperature rise is prevented, so that the area density measuring precision is improved.

The embodiment of the application provides an area density measuring device which comprises a ray emitter, a ray receiver and a thermal management mechanism; the ray emitter and the ray receiver are oppositely arranged to form a detection space; the ray emitter is used for emitting rays to the sheet-shaped detected object entering the detection space; the ray receiver is used for receiving the rays transmitted through the measured object so as to measure the surface density of the measured object; the thermal management mechanism is arranged outside an inlet of the detection space and is used for transmitting air flow between the detected object and the ray receiver.

In this embodiment of the application, the thermal management mechanism outside the detection space inlet is arranged to transfer air flow between the measured object and the ray receiver so as to accelerate the air flow on the surface of the ray receiver, namely, the temperature of the air around the heating source (the ray receiver) in the surface density measurement equipment can be reduced, and the change of ray intensity caused by temperature rise is prevented, so that the surface density measurement precision is improved.

In some embodiments, the thermal management mechanism includes a gas flow delivery device for outputting a gas as the gas flow acting on the object under test.

According to the embodiment, the air is converted into the air flow acting on the detected object through the air flow conveying device, so that dust particles on the surface of the detected object before entering the detection space can be removed, and the influence of the dust particles on the ray intensity is reduced; on the other hand, the air flow acting on the measured object is transmitted between the measured object and the ray receiver, so that the air flow between the measured object and the ray receiver can be accelerated, the influence of temperature rise on the air refractive index is reduced, and the surface density measurement accuracy is improved.

In some embodiments, the angle between the direction of the airflow output from the airflow transmitting device and the normal of the plane of the object to be measured is 25-40 degrees. The angle between the direction of the air flow output from the air guide groove and the normal line of the plane of the measured object is set to be 25-40 degrees, so that the stabilizing effect and the dedusting and heat dissipation effects of the measured object can be balanced better.

In some embodiments, the thermal management mechanism further comprises a flow stabilizer; the current stabilizer is used for collecting the air flow and transmitting the air flow to the position between the measured object and the ray receiver. The pressure stabilizing module can enable air flow to be more concentrated and stable, solves the problems of the object to be measured going down and wrinkling, and the like, and ensures the stability of the object to be measured, thereby improving the surface density measurement precision.

In some embodiments, the flow stabilizer is further configured to accelerate the airflow. The current stabilizer accelerates the air flow and then transmits the air flow to the space between the measured object and the ray receiver, thereby being beneficial to improving the heat dissipation effect of the air around the ray receiver, preventing the change of ray intensity caused by the temperature rise and improving the surface density measurement precision.

In some embodiments, the flow stabilizer is a reducer structure. After the airflow sweeps the measured object to lose a certain amount of energy, the high-speed airflow which is collected by the reducer and is accelerated again can improve the dust removal effect and the heat radiation effect between the measured object and the ray receiver, and the stability of the measured object can be ensured under relatively low pressure, so that the surface density measurement precision is improved.

In some embodiments, the reducer structure is a tapered quadrilateral.

In some embodiments, the air inlet of the tapered quadrangular body is disposed on the left end face and the upper bottom face of the tapered quadrangular body, and the air outlet of the tapered quadrangular body is disposed on the right end face of the tapered quadrangular body.

According to the embodiment, the air inlet is arranged on the upper bottom surface of the tapered quadrangular body, so that air flow can be guided into the tapered quadrangular body, more air flow reflected from the measured object can be collected, the air flow intensity is increased, a better heat dissipation effect is achieved on air around the ray sensor, the change of ray intensity caused by temperature rise is prevented, and the surface density measurement accuracy is improved.

In some embodiments, the lower bottom surface of the tapered quadrangular body is flush with the upper bottom surface of the radiation receiver. Therefore, the air flow can be transmitted between the measured object and the ray receiver to the greatest extent, the dust removal effect and the heat radiation effect between the measured object and the ray receiver are further improved, and the surface density measurement accuracy is improved.

In some embodiments, the thermal management mechanism further comprises a cooling device for cooling the gas prior to entering the gas flow delivery device. Compared with common gas, the cooled gas is output as gas flow through the gas flow transmission device and then blown between the measured object and the ray receiver, the cooling effect is better, and the cooling or heat dissipation of the air around the ray receiver can be accelerated, so that the change of the ray intensity caused by the temperature rise is reduced, and the surface density measurement precision is improved.

In some embodiments, the cooling device is a vortex cooling tube.

In some embodiments, the surface density measurement device further comprises a carrier roller, and the carrier roller and the airflow conveying device are arranged on two sides of the measured object oppositely. The carrier roller and the airflow conveying device are arranged on two sides of the measured object, and the carrier roller can counteract the force of the airflow output by the airflow conveying device on the measured object so as to prevent the measured object from shaking, thereby improving the surface density measurement precision.

In some embodiments, the idler is disposed at a location where the airflow is incident to the test object. The mode exactly counteracts the force of the lamellar air flow output by the air guide groove on the measured object, prevents the measured object from being blown up due to overlarge lamellar air flow impact force, further ensures the stability of the measured object, and improves the surface density measurement accuracy.

In some embodiments, the airflow delivery device comprises a cavity and a cover plate; the cavity is provided with at least one ventilation hole; the cover plate is arranged on the cavity, and one end of the cover plate, which is close to the air holes, extends out of the air guide groove; the cavity is used for receiving gas, and the gas is output as air flow through the air holes and the air guide grooves.

In this application embodiment, after the gas gets into the cavity, can disperse the storage in the great cavity in space, then pass the bleeder vent earlier under the effect of pressure and transmit to the air guide groove, the balanced air current that the rethread air guide groove formed can be used for cooling down or dust removal to target object, and guarantees target object's stability.

In some embodiments, the cavity comprises an air cavity and a backing plate; the air cavity is provided with an opening; the pad covers the opening, and one end of the pad is provided with the at least one ventilation hole; the cover plate is arranged on the base plate. The cavity is divided into the air cavity and the backing plate, so that the manufacturing process difficulty of the cavity can be reduced compared with the direct manufacturing of the cavity with at least one ventilation hole.

In some embodiments, the air cavity comprises a first cavity and a second cavity, the first cavity and the second cavity being connected by a conduit; the first chamber is used for conveying the gas to the second chamber through the pipeline so as to store the gas in the second chamber in a pressure stabilizing way.

According to the embodiment, the gas enters the second cavity through the pipeline after being buffered in the first cavity, and the second cavity can uniformly distribute the gas by utilizing the inner space of the second cavity, so that the gas in the second cavity is stored in a stable pressure mode, stable gas flow is output from the ventilation holes and the gas guide grooves, and when the gas flow acts on a target object, the stability of the target object can be improved.

In some embodiments, an inlet is provided at a central position of the bottom plate or the side plate of the first chamber, through which inlet the gas enters the first chamber.

According to the embodiment, the air inlet is arranged at the middle position of the bottom plate or the side plate of the first cavity, so that the air can be uniformly distributed as much as possible after entering the second cavity from the first cavity, the air flow output from the air guide groove is more uniform, and the stability of a target object can be improved when the air flow acts on the target object.

In some embodiments, the second cavity, the backing plate, and the cover plate are interconnected by a connector. The second cavity, the backing plate and the cover plate are tightly connected through the connecting piece, so that the pressure can be stored in the air cavity. The second cavity, the backing plate and the cover plate are tightly connected with each other through the connecting piece, so that gas can be prevented from leaking from the positions except the air holes and the air guide grooves.

In some embodiments, the number of the connectors is three, the three connectors are distributed in a triangular shape, and the pipeline corresponds to the position of one of the connectors. The connecting pieces are distributed in a triangular mode, can bear larger atmospheric pressure, and have better sealing effect. In addition, one of the connecting pieces corresponds to the pipeline, gas output from the pipeline can be split, so that the gas is uniformly distributed in the second cavity, the air pressure of the air hole output air flow near the position of the inner wall of the second cavity opposite to the pipeline is prevented from being too large, and the output air flow is more stable.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a side cross-sectional view of an areal density meter disclosed in an embodiment of the application;

FIG. 2 is a schematic diagram of the internal structure of an areal density meter according to an embodiment of the disclosure;

FIG. 3 is a side cross-sectional view of an areal density measurement apparatus disclosed in an embodiment of the application;

FIG. 4 is a side cross-sectional view of another areal density measurement apparatus disclosed in an embodiment of the application;

FIG. 5 is an enlarged view of a portion of an area density measurement device disclosed in an embodiment of the present application;

FIG. 6 is a schematic structural diagram of a current stabilizer disclosed in an embodiment of the present application;

FIG. 7 is a schematic view of a cooling device according to an embodiment of the present disclosure;

FIG. 8 is a side cross-sectional view of yet another areal density measurement apparatus disclosed in an embodiment of the application;

FIG. 9 is a schematic view of the internal structure of yet another surface density measurement device disclosed in an embodiment of the present application;

FIG. 10 is an enlarged view of a portion of yet another area density measurement device disclosed in an embodiment of the present application;

FIG. 11 is a schematic view of an airflow delivery device according to an embodiment of the present application;

fig. 12 is a cross-sectional view of an air flow delivery device as disclosed in an embodiment of the present application.

In the drawings, the drawings are not drawn to scale.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the present application and are not intended to limit the scope of the application, i.e., the application is not limited to the embodiments described.

In the description of the present application, it is to be noted that, unless otherwise indicated, the meaning of "plurality" is two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like indicate an orientation or positional relationship merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The "vertical" is not strictly vertical but is within the allowable error range. "parallel" is not strictly parallel but is within the tolerance of the error.

The directional terms appearing in the following description are all directions shown in the drawings and do not limit the specific structure of the present application. In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the terms in the present application can be understood as appropriate by one of ordinary skill in the art.

The new energy industry of China develops rapidly in the low-carbon economic age. The lithium battery which is one of new energy sources has been used for comprehensively replacing the traditional lead-acid, nickel-hydrogen and nickel-cadmium batteries as the most important energy storage original in the twenty-first century because of higher specific energy and environmental protection and no pollution of materials. The positive and negative pole pieces are the most important components of the lithium battery, and the quality of the positive and negative pole pieces directly influences the actual use effect of the whole battery and even the life safety of users, so that the detection and control of the manufacturing quality of the pole pieces, particularly the surface density, are particularly important.

The lithium electrode positive and negative electrode plate surface density measuring instrument is a high-precision instrument special for detecting the electrode plate surface density, and not only is on-line real-time detection realized, but also the detection precision is required to be controlled within +/-0.1% of a true value. Fig. 1 and 2 provide schematic block diagrams of an areal density meter 100. Fig. 1 is a side sectional view of the surface density measuring instrument 100, and fig. 2 is an internal structural view of the surface density measuring instrument 100. As shown in fig. 1, the areal density meter 100 can include a housing 110, a set of pass rollers, and a measurement device. The measuring device consists of a radiation emitter 111 and a radiation receiver 112, which are arranged between two roller sets, four roller sets 113 form two symmetrically arranged roller sets, and pole pieces 114 are wound in a shape of a Chinese character 'ji'. The areal density meter 100 can also include a foot 115 for supporting the instrument. When the surface density of the pole piece 114 is measured, the radiation emitter 111 emits radiation to the pole piece 114, the radiation penetrates through the pole piece 114 and is received by the radiation receiver 112, and the surface density of the pole piece 114 can be calculated by measuring the radiation intensity before and after penetrating through the pole piece 114.

When the surface density measuring instrument operates for a long time, the temperature in the surface density measuring instrument gradually rises, and especially when the air temperature between the measuring device in the measuring instrument and the pole piece 114 changes, the air density is caused to change, so that the refractive index of rays and the intensity of the rays are affected, and finally the surface density measuring precision is affected. The conventional surface density measuring instrument 100 has an exhaust casing and an exhaust fan in the casing 110, but the surface density measuring instrument 100 can only dissipate heat in its entirety, and has a limited heat dissipating capability for a heat source (radiation receiver 112), and if the air volume is increased, pole pieces shake, and the surface density measuring accuracy is deteriorated.

In view of this, the embodiment of the application provides an area density measurement device, and a thermal management mechanism is arranged outside an inlet of a detection space formed by a radiation emitter 111 and a radiation receiver 112, and the thermal management mechanism can transmit airflow between a measured object and the radiation receiver, accelerate the air flow on the surface of the radiation receiver, accurately cool the air around a heating source, reduce the influence of temperature rise on measurement precision, and thus improve the area density measurement precision.

The surface density measuring equipment provided by the embodiment of the application can be suitable for measuring the surface density of the lithium battery pole piece, for example, when the surface density measuring equipment is applied to a lithium battery coating process, the surface density measuring equipment can be placed after an unwinding of a coating machine and before a coating head to measure the surface density of a substrate to be coated; the surface density of the dried pole piece can also be measured outside the oven and before winding. In addition, the surface density measuring device provided by the embodiment of the application is also suitable for surface density measurement of other sheet products, such as a diaphragm, paper and the like.

Fig. 2 is a schematic structural diagram of an area density measurement apparatus 200 according to an embodiment of the present application. Fig. 2 is a side sectional view of the surface density measuring device 200, in which the external structures such as the housing, the legs, and the like of the surface density measuring device 200 are omitted.

As shown in fig. 2, the areal density measurement apparatus 200 includes a radiation emitter 21, a radiation receiver 22, and a thermal management mechanism 23. The radiation emitter 21 and the radiation receiver 22 are disposed opposite to each other to form a detection space 24, the radiation emitter 21 is used for emitting radiation to a sheet-shaped object 25 entering the detection space 24, and the radiation receiver 22 is used for receiving radiation transmitted through the object 25 so as to measure the surface density of the object 25. The thermal management mechanism 23 is disposed outside the entrance of the detection space 24 for conveying an air flow between the object 25 to be detected and the radiation receiver 22.

The radiation emitter 21 may be a radiation source, and illustratively, the radiation emitter 21 may be an X-ray radiation source, a beta-ray radiation source, or the like. The radiation emitter 21 may emit different types of radiation for different subjects 25. For example, when the object 25 to be measured is a positive electrode sheet, the radiation emitter 21 may emit an X-ray source and emit an X-ray; when the object 25 is a negative electrode sheet, the radiation emitter 21 may emit a β -ray source and emit a β -ray.

The radiation receiver 22 may be an ionization chamber, and the intensity of the ionizing radiation, i.e. the intensity of the radiation, may be measured using the ionizing radiation effect of the ionizing radiation. The radiation receiver 22 has an operating circuit therein, and the surface density of the object 25 to be measured can be calculated from the intensity of radiation emitted from the radiation emitter 21 and the intensity of radiation received thereby.

The object 25 may be a positive electrode sheet or a negative electrode sheet of a lithium battery, or may be a separator, paper, or other sheet-like product.

The radiation emitter 21 and the radiation receiver 22 are arranged face to form a detection space 24 or a detection gap, the detected object 25 enters the detection space 24 from the entrance of the detection space 24 under the power action of the roller 26, and the radiation receiver 21 and the radiation receiver 22 can move in a zigzag manner to measure the surface density of the detected object 25.

Alternatively, in some embodiments, the radiation emitter 21 may be the radiation emitter 111 of fig. 1, the radiation receiver 22 may be the radiation receiver 112 of fig. 1, and the idler 26 may be the idler 113 of fig. 1.

Alternatively, in some embodiments, the positions of the radiation emitter 21 and the radiation receiver 22 may be interchanged.

When the working circuit of the radiation receiver 22 runs for a long time, a large amount of heat is generated, and the temperature in the detection space 24 is increased to cause the air density to change, so that the refractive index of the radiation in the detection space 24 is affected, and the intensity of the radiation received by the radiation receiver 22 is caused to have errors, so that the surface density measurement accuracy is affected.

As shown in fig. 3, the thermal management mechanism 23 is disposed outside the entrance of the detection space 24 and near the side of the radiation receiver 22. The thermal management mechanism 23 may be, for example, an L-shaped tube, and the air is formed into an air flow by the L-shaped tube and then transferred between the measured object 25 and the radiation receiver 22, so as to accelerate the air flow on the surface of the radiation receiver 22, thereby achieving the heat dissipation effect. The size of the air outlet of the L-shaped pipe may be equal to the size of the radiation receiver 22 in the length direction of the radiation receiver 22.

Alternatively, in the embodiment of the present application, the gas may be a compressed gas, where the compressed gas refers to a gas with an increased pressure.

In the embodiment of the application, the thermal management mechanism 23 is arranged outside the inlet of the detection space 24, and the thermal management mechanism 23 can transmit air flow between the detected object 25 and the radiation receiver 22 so as to accelerate air flow on the surface of the radiation receiver 22, accurately cool down the heating source (the radiation receiver 22), reduce radiation intensity change caused by temperature rise, and further improve the surface density measurement precision.

Alternatively, in some embodiments, as shown in FIG. 4, thermal management mechanism 23 may include a gas flow delivery device 230 for outputting a gas as a gas flow against object 25.

Alternatively, in some embodiments, as shown in fig. 4, the air flow transmitting device 230 may be disposed on a side close to the radiation receiver 22, so as to transmit the air flow from the side close to the radiation receiver 22 to between the object (25) to be tested and the radiation receiver (22), thereby achieving a better heat dissipation effect.

As shown in fig. 4, the air flow conveyor 230 may be fixed to the radiation receiver 22. The size of the air flow conveyor 230 may be equal to the size of the radiation receiver 22 in the length direction of the radiation receiver 22. The air flow transmission device 230 may be connected to an external exhaust duct through which air may enter the air flow transmission device 230 such that the air flow transmission device 230 converts the air into an air flow acting on the object 25 to be measured. In the embodiment of the application, the airflow can be laminar airflow, and compared with the common airflow, the laminar airflow is more concentrated and the flow speed and the direction are convenient to control.

It should be appreciated that when the object 25 enters the surface density measuring device 200 from the outside, some dust particles may be entrained, and when the dust particles enter the detection space 24 along with the object 25, the dust particles cause a change in the intensity of the radiation, thereby affecting the surface density measurement accuracy of the object 25. After the airflow transmitting device 230 converts the air into the airflow, the airflow acts on the surface of the object 25 through the air outlet of the airflow transmitting device 230 to purge the dust particles on the surface of the object 25. Further, the air flow acting on the surface of the object 25 is continuously transmitted between the object 25 and the radiation receiver 22, so as to accelerate the air flow between the object 25 and the radiation receiver 22.

The gas is output as the gas flow acting on the object 25 through the gas flow transmission device 230, on one hand, dust particles on the surface of the object 25 before entering the detection space 24 can be removed, and the influence of the dust particles on the ray intensity is reduced; on the other hand, the air flow acting on the object 25 is transmitted between the object 25 and the ray receiver 22, so that the air flow between the object 25 and the ray receiver 22 can be accelerated, the influence of temperature rise on the refractive index of the ray is reduced, and the surface density measurement accuracy is improved.

Alternatively, in some embodiments, as shown in fig. 5, the angle a between the direction of the output air flow from the air flow transmission device 230 and the normal to the plane of the object 25 is 25-40 degrees.

When the angle a between the direction of the air flow output from the air flow transmission device 230 and the normal line of the plane of the object 25 is too small, the air flow blown to the object 25 may be too large, which affects the stability of the object 25; too large an angle a may cause too small an air flow to the object 25 to be measured, and the dust removal and heat dissipation effects are poor. Therefore, setting the angle a to 25-40 degrees can better balance the stabilizing effect and the dust removal heat dissipation effect of the object 25.

Illustratively, the angle A between the direction of the output air flow from the air flow transmission device 230 and the normal of the plane of the object 25 is 30 degrees.

Optionally, in some embodiments, as shown in fig. 4, the thermal management mechanism 23 may further include a flow stabilizer 240, where the flow stabilizer 240 is configured to collect and transmit the airflow between the object 25 and the radiation receiver 22.

The flow stabilizer 240 may be disposed between the object 25 and the airflow delivery device 230. After the airflow transmitted by the airflow transmitting device 230 sweeps the object 25, the airflow can be collected by the flow stabilizing device 240, and the collected airflow is transmitted between the object 25 and the radiation receiver 22 in a pressure stabilizing manner. Therefore, the voltage stabilizing module 240 can make the air flow more concentrated and stable, solve the problems of the object 25 going down the couch, wrinkling, etc., and ensure the stability of the object 25, thereby improving the surface density measurement accuracy.

Optionally, in some embodiments, the flow stabilizer 240 also serves to accelerate the airflow.

It should be understood that after the air flow sweeps the object 25, a part of energy is lost, the speed of the air flow is reduced, and the current stabilizer 240 can accelerate the air flow and retransmit the air flow between the object 25 and the radiation receiver 22, so as to improve the heat dissipation effect of the air around the radiation receiver 22, prevent the change of the radiation intensity caused by the temperature rise, and improve the measurement accuracy of the surface density.

Alternatively, in some embodiments, the flow stabilizer 240 may be a reducer structure.

The flow stabilizer 240 is designed in a reducing pipe structure, that is, the cross-sectional area of the reducing pipe is smaller from the left end face to the right end face, and the reducing design can utilize the pressure drop of the gas to accelerate the gas flow and reduce the pressure. The specific principle is as follows, the length of the reducer is smaller, and the speed of the air flow is higher, so the time required for the air flow to pass through the reducer is short, the heat exchange between the air flow and the side wall of the reducer is negligible, therefore, the flow of the air flow in the reducer can be regarded as an adiabatic flow process, and the change rate of the sectional area of the reducer is as follows according to a continuity equation:

for the constant entropy flow of the gas in the reducer, the relationship between the cross-sectional area change rate and the flow velocity change rate is as follows:

Wherein c _f Is the velocity of airflow in the reducer, c is the sound velocity, M _a Mach number, S is the cross-sectional area of the reducer, when the flow velocity c _f Less than sound velocity c, i.e. Mach number less than 1, with decreasing cross-sectional area S, airflow velocity c _f And consequently becomes larger.

Therefore, after the airflow sweeps the object 25 to be measured to lose a certain amount of energy, the energy is collected by the reducer and increased again, so that the dust removal effect and the heat radiation effect between the object 25 and the radiation receiver 22 can be improved, and the stability of the object 25 can be ensured at a relatively low pressure.

Alternatively, in some embodiments, the reducer structure may be a quadrilateral as shown in fig. 6. That is, the left end face and the right end face of the reducer are in quadrilateral structures, and can be better attached to the air flow conveying device 230, so that more air flows output by the air flow conveying device 230 can be collected, and the air flow strength is increased.

Alternatively, in some embodiments, as shown in fig. 6, the air inlet 241 of the tapered quadrangular body is disposed at the left end face and the upper bottom face of the tapered quadrangular body, and the air outlet 242 of the tapered quadrangular body is disposed at the right end face of the tapered quadrangular body.

The upper bottom surface of the tapered quadrangular body has a part of opening, and the opening of the left end surface and the opening of the upper bottom surface together form the air inlet 241 of the tapered quadrangular body.

After the air flow blows to the measured object 25, a huge vortex is formed in front of the flow stabilizer 240, and a part of air inlets are arranged on the upper bottom surface of the tapered quadrangular body to guide the air flow to enter the tapered quadrangular body so as to collect more air flow reflected from the measured object 25, thereby increasing the air flow intensity, achieving better heat dissipation effect on air around the radiation sensor 22, preventing the radiation intensity from changing due to temperature rise, and improving the surface density measurement precision.

Alternatively, in some embodiments, the lower bottom surface of the tapered quadrangular body is flush with the upper bottom surface of the radiation receiver 22. Therefore, the air flow can be transmitted between the measured object 25 and the ray receiver 22 to the maximum extent, and the dust removing effect and the heat radiating effect between the measured object 25 and the ray receiver 22 are further improved, so that the surface density measuring precision is improved.

Optionally, in some embodiments, as shown in FIG. 4, the thermal management mechanism 23 may also include a cooling device 250 for cooling the gas prior to entering the gas flow delivery device 230.

Specifically, the cool air outlet of the cooling device 250 may be connected to the air inlet 2314 of the air flow delivery device 230. After the air is inputted into the cooling device 250, the cooling device 250 generates cold air through internal energy conversion, and then the cold air is transferred to the air flow transferring device 230 through a cold air outlet. The cooling device 250 may cool the gas in different ways, such as by vortex cooling, which is not limited in this application.

Compared with the common gas, the cooled gas is converted into the gas flow through the gas flow conveying device 230 and then blown between the measured object 25 and the ray receiver 22, so that the cooling effect is better, and the cooling or heat dissipation of the air around the ray receiver 22 can be accelerated, thereby reducing the change of the ray intensity caused by the temperature rise and improving the surface density measurement precision.

Alternatively, in some embodiments, as shown in FIG. 7, the cooling device 250 may comprise a vortex cooling tube.

Specifically, the air inlet 251 of the vortex cooling pipe is connected to an external exhaust pipe, air enters the vortex cooling pipe through the external exhaust pipe and the air inlet 251 of the vortex cooling pipe, the air is cooled down through energy conversion inside the vortex pipe, cold air is generated at one end, a cold air outlet 252 is arranged at one end of the cold air, the cold air is communicated with the air inlet 2314 of the air flow conveying device 230, hot air is generated at the other end of the cold air, and a hot air outlet 253 is arranged at one end of the hot air. One end of the hot air can be provided with a small adjustable valve, and the temperature and the air flow of the cold air flow are adjusted by a manual adjusting knob.

Optionally, in some embodiments, as shown in fig. 8 and 9, the surface density measurement apparatus 200 may further include a carrier roller 27, where the carrier roller 27 is disposed opposite to the airflow conveying device 230 on two sides of the measured object 25, for limiting shake of the measured object 25.

As shown in fig. 9, idler roller 27 may be the same length as overroller 26 and is horizontally tangent to overroller 26. The idler roller 27 may be driven, i.e., driven, and rotates as the object 25 moves. When the airflow acts on the object 25, if the airflow is too large, the object 25 may be blown up to cause shaking of the object 25, and the carrier roller 27 and the airflow transmission device 230 are disposed on two sides of the object 25, so as to apply pressure to the direction of the object to counteract the force of the airflow output by the airflow transmission device 230 acting on the object 25, so as to prevent shaking of the object 25, ensure stability of the object 25, and improve the measurement accuracy of the surface density.

Alternatively, in some embodiments, as shown in fig. 8 and 9, idler rollers 27 may also be disposed at the outlet of detection space 24, opposite air flow conveyor 230 along object under test 25. The two idlers 27 may be equidistant from the radiation emitter 21. The carrier roller 27 can counteract the force of the air flow output from the flow stabilizer 240 on the measured object 25, prevent the measured object 25 from shaking, and ensure the stability of the measured object 25, thereby improving the surface density measurement accuracy.

Fig. 10 is a partial enlarged view of fig. 9. Alternatively, in some embodiments, as shown in fig. 10, the idlers 27 may be provided at a position where the air flow is incident to the object 25.

When the airflow blows to the object 25, an eddy current is formed in front of the flow stabilizer 240 and is tangential to the carrier roller 27, so that the object 25 is tightly attached to the carrier roller 27, and the stability of the object 25 is enhanced while dust removal is performed. That is, the carrier roller 27 is disposed at a position where the air flow is incident to the object 25, so as to exactly offset the force of the laminar air flow output by the air guide groove 2321 on the object 25, so as to prevent the object 25 from being blown up due to the overlarge impact force of the laminar air flow, further ensure the stability of the object 25, and improve the measurement accuracy of the surface density.

Fig. 11 and 12 are schematic structural views of an airflow transmission device 230 according to an embodiment of the present application. The gas flow transfer device 230 may output the gas as a gas flow for low temperature and dust removal.

Alternatively, the air flow transmission device 230 may be divided into multiple sections, or multiple air flow transmission devices 230 may be spliced according to actual requirements to meet different length requirements, which is not limited in this application. As shown in fig. 11, the air flow conveyor 230 may be divided into three sections, each of which may be identical. When the airflow delivery device 230 is divided into multiple sections, the sectional maintenance of different parts in the airflow delivery device 230 is facilitated, specifically, when a certain part in the airflow delivery device 230 has a problem, only the corresponding part needs to be repaired or replaced, and the whole airflow delivery device 230 does not need to be repaired or replaced.

Optionally, in some embodiments, referring to fig. 11, the airflow transmitting device 230 may include a cavity 231 and a cover 232, the cavity 231 is provided with at least one ventilation hole 2341, the cover 232 is disposed on the cavity 231, and an end of the cover 232 close to the ventilation hole 2341 extends out of the air guide groove 2321. The chamber 231 is configured to receive a gas, and the gas outputs a gas flow through the gas vent 2341 and the gas guide groove 2321.

The cavity 231 has a space for storing gas, and at least one ventilation hole 2341 is provided on the cavity 231, so that the gas in the cavity 231 forms at least one air flow through the ventilation hole 2341. At least one ventilation hole 2341 may be provided on one wall of the cavity 231.

The cover 232 may be flat plate-shaped, and extend in the height direction of the chamber 230 at one end near the ventilation hole 2341, and may form a narrow gap with the wall of the chamber 231 to obtain the air guide groove 2321. After entering the cavity 231, the gas can be stored in the cavity 231 with larger space in a dispersed way, and then is transmitted to the gas guide groove 2321 through the ventilation holes 2341 under the action of pressure, and then is formed into balanced gas flow through the gas guide groove 2321.

It should be appreciated that since the air guide 2321 is a slit formed by the cover 232 and the wall of the cavity, the air flow output through the air guide 2321 may be regarded as a sheet-like air flow. When the air guide groove 2321 is narrow, a laminar air flow may be output.

The sheet-shaped balanced air flow output from the air guide groove 2321 can be used for cooling or dedusting a target object and guaranteeing the stability of the target object, so that the sheet-shaped balanced air flow is particularly suitable for instruments or equipment with high requirements on precision measurement.

Illustratively, when the airflow transmitting device 230 is applied to the above-described surface density measuring device 200, the target object may be the above-described object under test 25 and the radiation receiver 22. Specifically, when the airflow conveying device 231 is applied to the above-mentioned surface density measuring apparatus 200, the airflow output by the airflow conveying device acts on the upper object 25, so that dust particles on the surface of the object 25 can be purged, and the dust particles are prevented from entering the detection space 24 to affect the surface density measuring accuracy. In addition, the air flow can enter the detection space 24 to accelerate the air flow on the surface of the radiation receiver 22, so as to achieve the heat dissipation effect.

Optionally, in some embodiments, the cavity 231 includes an air cavity 233 and a cushion plate 234, the air cavity 231 has an opening, the cushion plate 234 covers the opening, one end of the cushion plate 234 is provided with at least one ventilation hole 2341, and a cover plate is provided on the cushion plate 234.

As shown in fig. 11, the cavity 231 may be formed of an air cavity 233 and a pad 234, the end surface of the air cavity 233 has an opening, and the pad 234 may be a flat plate covering the opening of the air cavity 233. One end of the pad 234 is provided with a plurality of ventilation holes 2341. The pad 234 may be considered to have a plurality of saw-tooth-shaped flat plates at one end, and the ventilation holes 2341 are gaps between saw teeth. The gas is transported out of the cavity 231 through at least one ventilation hole 2341 under the action of pressure to form at least one air flow. The cover 232 is disposed above the base plate 234 and outputs at least one air flow as a sheet-like uniform air flow through the air guide grooves 2321.

Dividing the cavity 231 into two parts, namely the air cavity 233 and the backing plate 234, can reduce the difficulty of the manufacturing process of the cavity 231 compared with directly manufacturing the cavity 231 with at least one ventilation hole 2341.

Alternatively, in some embodiments, as shown in fig. 11 or 12, the air cavity 233 may include a first cavity 2331 and a second cavity 2332, the first cavity 2331 and the second cavity 2332 being connected by a conduit 2333, the first cavity 2331 may be used to transfer a gas through the conduit 2333 to the second cavity 2332 to store the gas in the second cavity 2332 at a regulated pressure.

In the embodiment of the present application, the first chamber 2331 and the second chamber 2332 may be integrally formed. The gas is buffered in the first chamber 2331 and then enters the second chamber 2332 through the pipeline 2333, and the second chamber 2332 can uniformly distribute the gas by using the inner space of the second chamber 2332, so that the gas in the second chamber 2332 is stored in a pressure-stabilizing manner, and stable gas flow is output from the gas vent 2341 and the gas guide groove 2321, and when the gas flow acts on a target object, the stability of the target object can be improved.

The first chamber 2331 may be a high pressure chamber whose chamber may have a high compression ratio for the gas such that the gas flow rate loss of the gas into the chamber is small and the pressure is large. Wherein the compression ratio represents the degree of compression of the gas. In addition, due to the coanda effect, the air flow output from the air guide groove 2321 drives the air around the outlet of the air guide groove 2321 to act on the object 25 together, thereby forming a sheet-like air flow with strong impact force and small shearing force. The sheet airflow with strong impact force and small shearing force can achieve better dust removal and cooling effects.

Optionally, in some embodiments, an inlet 2334 is provided at a middle position of the bottom plate or side plate of the first chamber 2331, through which inlet 2334 the gas enters the first chamber 2331.

As shown in fig. 12, gas enters the first chamber 2331 through the gas inlet 2334 of the gas chamber 233. The air inlet 2334 may be disposed at a middle position of the bottom plate of the first chamber 2331, or may be disposed at a middle position of the side plate, and the disposition position of the air inlet 2334 may be selected according to actual conditions.

The air inlet 2334 is arranged at the middle position of the bottom plate or the side plate of the first chamber 2331, so that air can be uniformly distributed as much as possible after entering the second chamber 2332 from the first chamber 2331, and the air flow output from the air guide groove 2321 is more uniform, and when the air flow acts on a target object, the stability of the target object can be improved.

In the embodiment of the present application, when the airflow delivery device 230 is divided into multiple sections, each section of the first chamber 2331 is communicated with each other, and each section of the first chamber 2331 has a corresponding air inlet 2334. Illustratively, the airflow delivery device 230 in fig. 5 is divided into three sections, and the number of air inlets 2334 may be three, and one air inlet 2334 corresponds to each section of the first chamber 2331. The air inlet 2334 can be connected with one or more air inlets 2334 according to actual requirements, and the unconnected air inlets 2334 can be sealed by sealing screws.

Optionally, in some embodiments, the second chamber 2332, the backing plate 234, and the cover plate 232 may be interconnected by a connector 235.

When the gas is stored in the gas chamber 233, the second chamber 2332 and the backing plate 234 and the cover plate 232 may be closely coupled to each other by the coupling member 235 to prevent the gas from leaking from the gas vent 2341 and the gas guide groove 2321. The connecting member 235 may connect the second chamber 2332, the backing plate 234 and the cover plate 232 by bonding or bolting, which is not limited in this application.

Alternatively, in some embodiments, as shown in fig. 11 and 12, the number of the connectors 235 is three, and the three connectors 235 are distributed in a triangle, and the pipe 2333 corresponds to the position of one of the connectors 235.

The connecting pieces 235 are distributed in a triangular shape, can bear larger atmospheric pressure, and have better sealing effect. When gas enters the second chamber 2332 from the first chamber 2333 through the pipe 2333, the opposite connecting piece 235 of the pipe 2333 can split the gas output from the pipe 2333, so that the gas is uniformly distributed in the second chamber 2332, and the gas pressure of the gas output from the single air vent 2341 near the inner wall position of the second chamber 2332 opposite to the pipe 2333 is prevented from being too large, so that the gas output is more stable.

Alternatively, the walls of the corresponding connector 235 of the conduit 2333 may be thickened to withstand the greater atmospheric pressure of the gas output from the conduit 2333.

Alternatively, in some embodiments, as shown in FIG. 4, an air flow delivery device 230 may be employed in an areal density measurement device 200 provided in embodiments of the application. Specifically, the air flow transmission device 230 may be disposed outside the inlet of the detection space 24 of the surface density measurement device 20, the air may enter the cooling device 250 through the external exhaust pipe from the air inlet of the cooling device, be cooled into cold air by the cooling module 250, enter the first chamber 2334 from the air inlet 2334 of the air flow transmission device 230, and then be transmitted to the second chamber 2332 through the pipeline, and when the air flow forms a strong impact force with a small shearing force through the air hole 2341 and the air guide groove 2321, on one hand, the air flow acts on the surface of the object 25 to be detected, and may remove dust on the surface of the object 25 to be detected, so as to prevent dust particles from entering the detection space 24 and affecting the radiation intensity; on the other hand, the air flow acting on the measured object 25 is reflected by the surface of the measured object 25 and enters the flow stabilizing device 240, the flow stabilizing device 240 can accelerate and stabilize the air flow, and then the air flow is transmitted between the measured object 25 and the ray receiver 22, so that the stability of the measured object 25 can be improved, the air around the ray receiver 22 can be cooled, the influence of temperature rise on the ray intensity is prevented, and the surface density measurement accuracy is improved.

In addition, the airflow transmitting device 230 provided in the embodiment of the present application may be applied to other situations where dust removal or cooling is required, for example, dust removal of a charge-coupled device (CCD) light source, which is not limited in this application.

While the present application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the present application. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. An areal density measurement device, characterized by comprising a radiation emitter (21), a radiation receiver (22), a thermal management mechanism (23);

the ray emitter (21) and the ray receiver (22) are arranged opposite to each other to form a detection space (24);

the ray emitter (21) is used for emitting rays to an object (25) to be detected entering the detection space (24);

the ray receiver (22) is used for receiving the rays transmitted through the measured object (25) so as to measure the surface density of the measured object (25);

The thermal management mechanism (23) is arranged outside the inlet of the detection space (24) and is used for conveying air flow between the detected object (25) and the ray receiver (22).

2. An areal density measurement apparatus according to claim 1, wherein the thermal management mechanism (23) comprises a gas flow transfer device (230) for outputting a gas as the gas flow acting on the object under test (25).

3. The areal density measurement apparatus of claim 2, wherein an angle a between a direction in which the air flow is output from the air flow conveying device (230) and a normal to a plane in which the object (25) to be measured is 25 to 40 degrees.

4. The areal density measurement apparatus of claim 2, wherein the thermal management mechanism (23) further comprises a flow stabilizer (240);

the flow stabilizer (240) is used for collecting the air flow and transmitting the air flow between the measured object (25) and the ray receiver (22).

5. The areal density measurement apparatus of claim 4 wherein the flow stabilizer (240) is further configured to accelerate the airflow.

6. The areal density measurement device of claim 5, wherein the flow stabilizer (240) is a reducer structure.

7. The areal density measurement device of claim 6 wherein the reducer structure is a tapered quadrilateral.

8. The areal density measurement device of claim 7 wherein the air inlet of the tapered quadrilateral is disposed on the left end face and the upper bottom face of the tapered quadrilateral and the air outlet of the tapered quadrilateral is disposed on the right end face of the tapered quadrilateral.

9. The areal density measurement device according to claim 8, wherein the lower bottom surface of the tapered quadrangular body is flush with the upper bottom surface of the radiation receiver (22).

10. An areal density measurement apparatus according to claim 2, wherein the thermal management mechanism (23) further comprises cooling means (250) for cooling the gas before entering the gas flow transfer means (230).

11. The areal density measurement apparatus of claim 10 wherein the cooling device (250) comprises a vortex cooling tube.

12. The areal density measurement apparatus according to any one of claims 2 to 11, wherein the areal density measurement apparatus (200) further comprises idlers (27), the idlers (27) being disposed on both sides of the test object (25) opposite the thermal management mechanism (23).

13. The areal density measurement device according to claim 12, characterized in that the carrier roller (27) is arranged at a position where the air flow is incident on the object (25).

14. The areal density measurement apparatus of claim 2, wherein the airflow delivery device (230) comprises a cavity (231) and a cover plate (232);

the cavity (231) is provided with at least one ventilation hole (2341);

the cover plate (232) is arranged on the cavity (231), and one end of the cover plate (232) close to the ventilation holes (2341) extends out of the air guide groove (2321);

the cavity (231) is used for receiving gas, and the gas is output as air flow through the air holes (2341) and the air guide grooves (2321).

15. The areal density measurement device according to claim 14, wherein the cavity (231) comprises an air cavity (233) and a backing plate (234);

-the air cavity (233) has an opening;

the cushion plate (234) covers the opening, and one end of the cushion plate (234) is provided with the at least one ventilation hole (2341);

the cover plate (232) is arranged on the backing plate (234).

16. The areal density measurement device according to claim 15, wherein the air cavity (233) comprises a first cavity (2331) and a second cavity (2332), the first cavity (2331) and the second cavity (2332) being connected by a conduit (2333);

The first chamber (2331) is configured to transfer the gas through the conduit (2333) to the second chamber (2332) to store the gas in the second chamber (2332) at a regulated pressure.

17. The areal density measurement device according to claim 16, wherein an inlet (2334) is provided in the middle of the bottom or side plate of the first chamber (2331), through which inlet (2334) the gas enters the first chamber (2331).

18. The areal density measurement device according to claim 16 or 17, wherein the second chamber (2332), the backing plate (234) and the cover plate (232) are connected to each other by a connection (235).

19. The areal density measurement device of claim 18, wherein the number of connectors (235) is three, the three connectors (235) being triangularly distributed, the conduit (2333) corresponding to the location of one of the connectors (235).