阅读说明：本技术 一种恒温工作站 (Constant temperature workstation ) 是由 刘占杰 贾洪涛 孔维益 刘飞飞 刘文杰 陈韩燕 于 2019-11-12 设计创作，主要内容包括：本发明公开了一种恒温工作站,包括工作室和空气循环系统,工作室具有工作台,空气循环系统包括回风口、进风口、与回风口连通的空气内循环通路、与进风口连通的空气外排通路,回风口和进风口设于工作台上,还包括用于与空气内循环通路内的空气进行热量交换的恒温模块,热量交换后的空气在空气循环系统的作用下进入回风口、并沿空气内循环通路循环流经工作室,使工作室具备恒温环境,外界空气在空气循环系统的作用下进入进风口、并沿空气外排通路排出,工作室的前方形成风障,为工作室提供洁净环境。该工作站同时提供洁净恒温的实验环境,成本低,有利于提高实验数据的准确性和操作舒适性。(The invention discloses a constant temperature workstation, which comprises a working chamber and an air circulation system, wherein the working chamber is provided with a workbench, the air circulation system comprises an air return opening, an air inlet opening, an air internal circulation passage communicated with the air return opening, an air external discharge passage communicated with the air inlet opening, the air return opening and the air inlet opening are arranged on the workbench, the constant temperature workstation is also provided with a constant temperature module for exchanging heat with air in the air internal circulation passage, the air after heat exchange enters the air return opening under the action of the air circulation system and circularly flows through the working chamber along the air internal circulation passage, so that the working chamber has a constant temperature environment, external air enters the air inlet opening and is discharged along the air external discharge passage under the action of the air circulation system, and an air barrier is formed in front of the working chamber to provide a clean environment for the working. The workstation provides a clean and constant-temperature experimental environment, is low in cost, and is favorable for improving the accuracy and the operation comfort of experimental data.)

1. A thermostatic workstation comprising a work chamber having a table, characterized in that it further comprises:

an air circulation system, comprising:

the air return opening is arranged on the workbench and used for air in the working chamber to perform air return circulation;

the air inlet is arranged on the workbench and used for allowing outside air to enter the workbench;

the air internal circulation passage is formed in the workstation and is communicated with the air return opening;

the air discharging passage is formed in the workstation and is communicated with the air inlet;

the constant temperature module is used for exchanging heat with the air in the air internal circulation passage;

wherein the content of the first and second substances,

the air after heat exchange enters the air return inlet under the action of the air circulation system and circularly flows through the working chamber along the air internal circulation path;

and outside air enters the air inlet under the action of the air circulation system and is discharged along the air discharge passage.

2. The thermostatic workstation of claim 1,

the workstation includes the cabinet body, the studio by the lateral wall of the cabinet body encloses, the workstation is located the below of studio, the interior circulation of air passageway with the passageway is arranged outward to the air all forms in the cabinet body is inside.

3. The thermostatic workstation of claim 2,

and a heat insulation layer is arranged between the air outer discharge passage and the air inner circulation passage.

4. The thermostatic workstation of claim 2,

the air return openings comprise a first air return opening and a second air return opening, the first air return opening is located on the front side of the workbench, and the second air return opening is located on the rear side of the workbench.

5. The thermostatic workstation of claim 4,

a first inclined part and a second inclined part are arranged on one side, close to the external environment, of the workbench, an included angle is formed between the first inclined part and the second inclined part, the first inclined part is close to the side of the workbench, the second inclined part is close to the external environment, and the intersection connecting position of the first inclined part and the second inclined part is higher than the workbench;

the first air return opening is formed in the first inclined portion, and the air inlet is formed in the second inclined portion.

6. The thermostatic workstation of claim 5,

a transparent window is arranged on the side, close to the external environment, of the working chamber;

the intersection connecting position of the first inclined part and the second inclined part is just opposite to the lower end edge of the transparent window.

7. The thermostatic workstation of claim 2,

the constant temperature module is a semiconductor wafer, one side of the semiconductor wafer is positioned in the air internal circulation passage, and the other side of the semiconductor wafer is positioned in the air external discharge passage.

8. The thermostatic workstation of claim 2,

an air supply air box is arranged in the air internal circulation passage and is positioned above the working chamber, an air supply fan is arranged on the air supply air box, and an air supply filter is arranged below the air supply air box;

an exhaust fan and an exhaust filter are arranged in the air exhaust passage.

9. The thermostatic workstation of claim 8,

and a flow equalizing plate is arranged between the air supply filter and the working chamber.

10. The thermostatic workstation of claim 9,

one side of the air supply air box is hinged with the cabinet body, the other side of the air supply air box is detachably and fixedly connected with the flow equalizing plate, one side of the air supply filter is arranged between the air supply air box and the cabinet body in a pressing mode, and the other side of the air supply filter is arranged between the air supply air box and the flow equalizing plate in a pressing mode.

11. The thermostatic workstation of any one of claims 1 to 10,

and the working chamber is internally provided with a wind speed sensor and a temperature sensor.

Technical Field

The invention relates to the technical field of workstations, in particular to a constant-temperature workstation.

Background

In the industries and fields of medical health, disease prevention and control, food health, biological pharmacy, environmental monitoring and the like, various experimental inspection contents are involved, a constant-temperature and clean laboratory environment is needed, operating personnel and experimental samples need to be protected, and cross contamination among the experimental samples is avoided.

In order to meet the required experimental environment requirements, an environmental laboratory is required to be equipped, and a biological safety cabinet is used for carrying out experimental operation. The temperature range of the environmental laboratory is 5-37 ℃, and the environmental temperature required by different experimental samples is different. For example, drugs and blood products require testing at 5 ℃ with minimal sample disruption; the activity of the animal and plant cells is best under the environment of 37 ℃.

The scheme of the environmental laboratory matched with the biological safety cabinet has the following disadvantages:

(1) the overall cost is too high, a large amount of manpower, material resources and fields are needed for building an environmental laboratory, the overall energy consumption is also very high for ensuring the environmental requirements in the laboratory in actual use, and the overall cost is too high due to the investment and the use of the biological safety cabinet;

(2) the operation comfort and the accuracy of the experimental data are poor, under the relatively low-temperature operation environment of 5-18 ℃, if the outdoor temperature is 30 ℃, the indoor and outdoor temperature difference is large, if the operator does not perform body protection, the body of the operator is possibly damaged, and the accuracy of the experimental data can be influenced by the large temperature difference.

The above information disclosed in this background section is only for enhancement of understanding of the background of the application and therefore it may comprise prior art that does not constitute known to a person of ordinary skill in the art.

Disclosure of Invention

In view of this, the invention provides a constant temperature workstation, which can provide a clean and constant temperature experimental environment, and can improve the operation comfort and the accuracy of experimental data, and has low cost.

In order to realize the purpose of the invention, the invention is realized by adopting the following technical scheme:

a thermostatic workstation comprising a work chamber, the work chamber having a table, further comprising: an air circulation system, comprising: the air return opening is arranged on the workbench and used for air in the working chamber to perform air return circulation; the air inlet is arranged on the workbench and used for allowing outside air to enter the workbench; the air internal circulation passage is formed in the workstation and is communicated with the air return opening; the air discharging passage is formed in the workstation and is communicated with the air inlet; the constant temperature module is used for exchanging heat with the air in the air internal circulation passage; the air after heat exchange enters the air return inlet under the action of the air circulation system and circularly flows through the working chamber along the air internal circulation path; and outside air enters the air inlet under the action of the air circulation system and is discharged along the air discharge passage.

Further, the workstation includes the cabinet body, the studio by the lateral wall of the cabinet body encloses, the workstation is located the below of studio, air inner circulation route with the passageway is arranged outward to the air all forms in the cabinet body is inside.

Further, a heat insulation layer is arranged between the air outer discharge passage and the air inner circulation passage.

Furthermore, the air return opening comprises a first air return opening and a second air return opening, the first air return opening is located on the front side of the workbench, and the second air return opening is located on the rear side of the workbench.

Furthermore, a first inclined part and a second inclined part are arranged on one side, close to the external environment, of the workbench, a certain included angle is formed between the first inclined part and the second inclined part, the first inclined part is close to the side of the workbench, the second inclined part is close to the external environment, and the intersection connecting position of the first inclined part and the second inclined part is higher than that of the workbench; the first air return opening is formed in the first inclined portion, and the air inlet is formed in the second inclined portion.

Further, a transparent window is arranged on the side, close to the external environment, of the working chamber; the intersection connecting position of the first inclined part and the second inclined part is just opposite to the lower end edge of the transparent window.

Furthermore, the constant temperature module is a semiconductor wafer, one side of the semiconductor wafer is positioned in the air internal circulation passage, and the other side of the semiconductor wafer is positioned in the air external discharge passage.

Further, an air supply air box is arranged in the air internal circulation passage and is positioned above the working chamber, an air supply fan is arranged on the air supply air box, and an air supply filter is arranged below the air supply air box; an exhaust fan and an exhaust filter are arranged in the air exhaust passage.

Furthermore, a flow equalizing plate is arranged between the air supply filter and the working chamber.

Furthermore, one side of the air supply air box is hinged with the cabinet body, the other side of the air supply air box is detachably and fixedly connected with the flow equalizing plate, one side of the air supply filter is arranged between the air supply air box and the cabinet body in a pressing mode, and the other side of the air supply filter is arranged between the air supply air box and the flow equalizing plate in a pressing mode.

Furthermore, an air speed sensor and a temperature sensor are arranged in the working chamber.

Compared with the prior art, the invention has the advantages and positive effects that:

the air in the air internal circulation passage keeps constant temperature under the action of the constant temperature module and circularly flows through the working chamber under the action of the air circulation system, so that the working chamber has a constant temperature environment, meanwhile, the outside air enters the air exhaust passage from the air inlet in front of the working chamber and is exhausted from the air exhaust passage under the action of the air circulation system, a wind barrier is formed in front of the working chamber, the outside environment is prevented from polluting the inside of the working chamber, a clean environment is provided for the working chamber, the constant temperature working station can simultaneously provide a clean and constant temperature experimental environment, an environmental laboratory and a biological safety cabinet are not required to be configured, and the cost is low; the clean and constant-temperature working room is beneficial to improving the accuracy of experimental data; in addition, during the operation, operating personnel only has the hand to be located the studio, and other parts of health are located the studio, can not cause operating personnel's discomfort because of the difference in temperature is big, improve the operation travelling comfort.

Other features and advantages of the present invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic cross-sectional view of an embodiment of a thermostatic workstation of the present invention;

FIG. 2 is a schematic view of the air flow of an embodiment of the thermostatic workstation of the present invention;

FIG. 3 is an enlarged view of portion A of FIG. 1;

FIG. 4 is an enlarged view of portion B of FIG. 1;

FIG. 5 is an enlarged view of portion C of FIG. 1;

fig. 6 is a schematic structural diagram of a thermostatic module according to an embodiment of the thermostatic workstation of the present invention.

Wherein, 01-working chamber, 02-working platform, 03-cabinet, 031-outer wall, 032-inner wall, 033-front wall, 034-middle partition, 04-air internal circulation path, 05-air external discharge path, 06-air return port, 061-first air return port, 062-second air return port, 07-air inlet, 08-air outlet, 09-constant temperature module, 091-semiconductor chip, 092-refrigeration/heating end, 093-heat dissipation end, 10-heat insulation layer, 11-air supply fan, 12-air exhaust fan, 13-air supply filter, 14-air exhaust filter, 15-flow equalizing plate, 151-air vent, 16-first connecting plate, 17-second connecting plate, 18-screw, 19-first inclined part, 20-second inclined part, 21-transparent window, 22-blowing bellows, 221-front side wall, 222-rear side wall, 223-upper wall, 23-temperature sensor, 24-wind speed sensor;

α -the angle between the first angled portion and the vertical plane, β -the angle between the second angled portion and the vertical plane.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The invention discloses a constant temperature workstation, which refers to fig. 1 and 2, wherein arrows in fig. 1 and 2 indicate the air flowing direction, the workstation comprises a working chamber 01 and an air circulating system, the working chamber 01 is provided with a working platform 02, and the air circulating system comprises an air return opening 06, an air inlet 07, an air internal circulating passage 04, an air external discharging passage 05 and a constant temperature module 09. Wherein, the return air inlet 06 and the air inlet 07 are both arranged on the workbench 02, the return air inlet 06 is used for air return circulation in the working chamber 01, and the air inlet 07 is used for outside air entering the workstation. The air return opening 06 is communicated with the air internal circulation passage 04, and the air inlet 07 is communicated with the air external discharge passage 05. The constant temperature module 09 is configured to exchange heat with air in the air internal circulation path 04 to heat or cool the air in the air internal circulation path 04, so as to keep the temperature constant. Air after heat exchange enters the air return opening 06 under the action of the air circulation system and circularly flows through the working chamber 01 along the air internal circulation passage 04, so that the working chamber 01 has a constant temperature environment, outside air enters the air inlet 07 under the action of the air circulation system and is discharged through the inside of the working station along the air external discharge passage 05, an air barrier is formed in front of the working chamber 01, the outside environment is prevented from polluting the inside of the working chamber 01, and a clean environment is provided for the working chamber 01.

The constant-temperature workstation can provide a clean and constant-temperature experimental environment at the same time, an environmental laboratory and a biological safety cabinet are not required to be configured, and the cost is low; the clean and constant-temperature working room 01 is beneficial to improving the accuracy of experimental data; in addition, during the operation, operating personnel only has the hand to be located the studio 01, and other parts of health are located the studio 01 outside, can not cause operating personnel's discomfort because of the difference in temperature is big, improve the operation travelling comfort.

Specifically, referring to fig. 1, the workstation includes a cabinet 03, the cabinet 03 includes an outer wall 031, an inner wall 032, and a front wall 033, the outer wall 031, the inner wall 032, and the front wall 033 enclose a cabinet inner cavity (not labeled), a middle partition 034 is disposed inside the cabinet inner cavity, the cabinet inner cavity is divided into two independent portions by the middle partition 034, one portion forms an air outer discharge passage 05, and the other portion forms an air inner circulation passage 04.

The working chamber 01 is surrounded by an inner wall 032, the working platform 02 is abutted against the lower and horizontally arranged inner wall 032, the working platform 02 can be a separately processed part, the lower inner wall 032 can also be used as the working platform 02, and the lower inner wall 032 is directly used as the working platform 02 in the embodiment.

An air outlet 08 is formed in an outer wall 031 located above, the air outlet 08 is communicated with an air outer discharge passage 05, and outside air flowing in from an air inlet 07 firstly flows into the air outer discharge passage 05 and then is discharged from the air outlet 08 along the air outer discharge passage 05. The air inlet 07 is preferably arranged on the front side of the workbench 02, and in the process that the outside air enters the air inlet 07 under the action of the air circulation system, a wind barrier is formed on the front side of the workbench 02 and isolates the inside of the working chamber 01 from the outside environment, so that the outside environment is prevented from polluting the inside of the clean and constant-temperature working chamber 01, and the stability of the inside environment of the working chamber 01 is kept.

An exhaust fan 12 is arranged in the air exhaust passage 05, the exhaust fan 12 is close to the exhaust port 08, and the exhaust fan 12 provides power for external air to enter the air exhaust passage 05 and to be exhausted outwards along the air exhaust passage 05.

An exhaust filter 14 is arranged at the exhaust outlet 08, and the air in the air exhaust passage 05 is filtered by the exhaust filter 14 and then exhausted to the outside, so that the pollution to the external environment is avoided.

Referring to fig. 1 to 4, the air return opening 06 includes a first air return opening 061 and a second air return opening 062, the first air return opening 061 is disposed at a front side (a side close to the external environment) of the workbench 02, the second air return opening 061 is disposed at a rear side (a side far from the external environment) of the workbench 02, the heat-exchanged air descending from above the working chamber 01 reaches the workbench 02 and is divided into two paths, one path enters the air internal circulation path 04 through the first air return opening 061, the other path enters the air internal circulation path 04 through the second air return opening 062, the two paths of return air join in the air internal circulation path 04 and then flows upward to above the working chamber 01 along the air internal circulation path 04, the air exchanges heat with the constant temperature module 09 in the air internal circulation path 04 to keep the temperature of the air constant, and then flows into the working chamber 01 in a circulating manner of descending, thereby realizing the circulation of the air in the working chamber 01 and the constant temperature, provides a constant temperature and stable environment for experimental operation.

Referring to fig. 3, a first inclined portion 19 and a second inclined portion 20 are disposed on one side of the workbench 02 close to the external environment, a certain included angle is formed between the first inclined portion 19 and the second inclined portion 20, the first inclined portion 19 is close to the working chamber 01 side, the second inclined portion 20 is close to the external environment side, the intersection connection position of the first inclined portion 19 and the second inclined portion 20 is higher than the workbench 02, the first air return opening 061 is disposed on the first inclined portion 19, and the air inlet 07 is disposed on the second inclined portion 20. The first inclined part 19 and the second inclined part 20 form a convex structure at the front side of the workbench 02, on one hand, the air can be conveniently guided and flowed, the wind loss is reduced, on the other hand, according to the flowing characteristic of the air, the air always flows along the easiest path, so that the external air can easily flow into the air discharging passage 05 through the air inlet 07, the air in the working chamber 01 can easily enter the air internal circulation passage 04 through the air return opening 06, the flowing of the air in the working chamber 01 and the air outside the working chamber 01 are not interfered with each other, and the environmental stability in the working chamber 01 is improved.

The studio 01 is close to the external environment side and is equipped with the transparent window 21, has certain clearance between the lower extreme edge of transparent window 21 and the workstation 02, and the operating personnel's of being convenient for hand is operated in stretching into the studio 01 through this clearance. The transparent window 21 plays a certain role in protecting the environment in the working chamber 01, and simultaneously, the operator can observe the operation in the working chamber 01 through the transparent window 21.

The intersection of the first inclined portion 19 and the second inclined portion 20 is preferably aligned with the lower edge of the transparent window 21, so as to form a separation in the space between the inside and the outside of the working chamber 01, thereby further ensuring that the air flows inside the working chamber 01 and outside the working chamber 01 do not interfere with each other.

In the present embodiment, the angle between the first inclined portion 19 and the vertical surface is represented as α, which is in the range of 30 to 60 °, 45 ° in the present embodiment, and the angle between the second inclined portion 20 and the vertical surface is represented as β, which is in the range of 40 to 70 °, 55 ° in the present embodiment.

In this embodiment, the first air return openings 061 are disposed at intervals, and the air inlet openings 07 are also disposed at intervals. The second return air inlet 062 is arranged at the bottom of the inner wall 032 and close to the position of the workbench 02, referring to fig. 3, the second return air inlet 062 is arranged in the horizontal direction, so that air in the working chamber 01 can conveniently enter the second return air inlet 062 under the suction action of the air supply fan 11, air return is facilitated, and air loss is reduced.

Referring to fig. 1 and 2, an air supply bellows 22 is provided in the air internal circulation passage 04, the air supply bellows 22 is located above the working chamber 01, the air supply bellows 22 is provided with an air supply fan 11, and an air supply filter 13 is provided below the air supply bellows 22. The air in the working chamber 01 enters the air internal circulation path 04 through the air return opening 06 under the suction force of the air supply fan 11, enters the air supply air box 22 along the air internal circulation path 04, and flows into the working chamber 01 through the air supply filter 13 under the action of the air supply fan 11 to form an air circulation loop, so that the air can circularly flow through the working chamber 01. The air supply filter 13 filters air flowing into the working chamber 01, thereby ensuring a clean environment in the working chamber 01.

It should be noted here that the side walls of the supply air box 22 can be understood as the above-mentioned inner wall 032 of the cabinet 03, that is, the side walls of the supply air box 22 form a part of the inner wall 032 of the cabinet.

Be equipped with flow equalizing plate 15 between air supply filter 13 and the studio 01, be equipped with a plurality of ventilation holes 151 that even interval set up on flow equalizing plate 15, a plurality of ventilation holes 151 play the effect of flow equalizing to downdraft, make the air current that descends can flow to the studio 01 inside evenly, make the air current of studio 01 inside more steady to provide more stable experimental environment.

Referring to fig. 5, the blowing air box 22 includes a front side wall 221, a rear side wall 222, and an upper wall 223, the blowing air fan 11 is disposed on the upper wall 223, the rear side wall 222 is hinged to a middle partition 034 in the cabinet body through a first connecting plate 16, the front side wall 221 is detachably and fixedly connected to the flow equalizing plate 15 through a second connecting plate 17, the rear side of the blowing filter 13 is pressed between the blowing air box 22 and the middle partition 034, and the front side of the blowing filter 13 is pressed between the blowing air box 22 and the flow equalizing plate 15.

When the air supply filter 13 is installed or replaced, the fixed connection relationship between the front side wall 221 and the flow equalizing plate 15 is removed, the air supply air box 22 is lifted upwards, the hinged position of the first connecting plate 16 and the middle partition plate 034 rotates, the air supply filter 13 is installed, the air supply filter 13 is placed in place, the air supply air box 22 is placed downwards, and then the front side wall 221 and the flow equalizing plate 15 are fixedly connected through the second connecting plate 17.

The front side wall 221 and the second connecting plate 17, and the second connecting plate 17 and the flow equalizing plate 15 are fastened by screws 18 to realize detachable fixed connection.

On the basis of any of the above embodiments, the heat insulating layer 10 is disposed between the air external discharge passage 05 and the air internal circulation passage 04, so as to prevent heat exchange between the air in the air external discharge passage 05 and the air in the air internal circulation passage 04, so that the air temperature in the air internal circulation passage 04 is more stable, and the energy consumption is reduced. In this embodiment, the thermal insulation layer 10 is fixedly disposed close to the middle partition 034.

On the basis of any of the above embodiments, referring to fig. 1 and 6, the thermostatic module 9 employs the semiconductor sheet 091, and is directly fixedly mounted to the middle partition 034 by the screws 18. The semiconductor technology is utilized to heat or refrigerate the air, and the structure is simple and the efficiency is high. The cooling/heating terminals 092 of the semiconductor chips 091 are located in the air inside circulation path 04, and the heat radiating terminals 093 of the semiconductor chips 091 are located in the air outside discharge path 05. The cooling/heating end 092 generates cooling/heating energy directly acting on the air in the air internal circulation passage 04 to regulate the temperature of the air, and the air circulates through the working chamber 01 to regulate the temperature in the working chamber 01, thereby maintaining the temperature in the working chamber 01 stable. The heat/cold of the heat dissipation end 093 is directly released into the air discharge passage 05 and discharged along with the air through the air outlet 08.

On the basis of any of the above embodiments, an air speed sensor 24 and a temperature sensor 23 are arranged in the working chamber 01, the air speed sensor 24 is used for measuring the air flow speed in the working chamber 01, and the temperature sensor 23 is used for measuring the temperature in the working chamber 01.

The control system of the workstation adjusts the rotating speed of the air supply fan 11 and the air exhaust fan 12 according to the air flow speed fed back by the air speed sensor 24, so that the air flow inside the working chamber 01 and the air flow outside the working chamber 01 are balanced and do not interfere with each other, the stability of the system is improved, and meanwhile, the air flow speed inside the working chamber 01 is monitored in real time and is kept stable, so that the influence on the operation articles is avoided.

The control system controls the start and stop of the semiconductor wafer 091 according to the temperature information fed back by the temperature sensor 23, so that the temperature of the air circulating through the working chamber 01 is kept stable, and the constant temperature environment of the working chamber 01 is realized.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.