阅读说明：本技术 一种无钢丝和帘子布的一体硫化免充气轮胎 (Integrated vulcanized non-pneumatic tire without steel wires and cord fabric ) 是由 袁征 于 2020-08-05 设计创作，主要内容包括：本发明涉及一种无钢丝和帘子布的一体硫化免充气轮胎,包括轮胎,橡胶轮胎沿着径向由外向内依次设置有胎体外层、交联层和胎芯发泡层；其中胎体外层和胎芯发泡层之间通过交联层实现两者的紧密交联融合连接,胎体外层、交联层和胎芯发泡层是采用两种不同材质的发泡条和条状胎面料经过复合和硫化成型工艺最终形成了一体式硫化轮胎结构,其中轮胎的胎体外层胎身两侧均环形分布有多个间隔排布的主立柱和副立柱。本发明克服了现有技术的不足,设计合理,结构紧凑,解决了现有的充气轮胎特别是电动车摩托车轮胎容易爆胎,防滑效果不佳以及挺性不足的问题,采用了发泡胎芯替代传统充气轮胎,防止爆胎,提高轮胎的使用寿命。(The invention relates to an integrally vulcanized inflation-free tire without steel wires and cord fabric, which comprises a tire, wherein a rubber tire is sequentially provided with a tire body outer layer, a cross-linking layer and a tire core foaming layer from outside to inside along the radial direction; the tire body outer layer, the cross-linking layer and the tire core foaming layer are in tight cross-linking fusion connection through the cross-linking layer, the tire body outer layer, the cross-linking layer and the tire core foaming layer are in an integrated vulcanized tire structure formed by adopting two foaming strips and strip-shaped tire surface materials made of different materials through a compounding and vulcanization molding process, and a plurality of main stand columns and auxiliary stand columns which are distributed at intervals are annularly distributed on two sides of a tire body outer layer and a tire body of the tire. The invention overcomes the defects of the prior art, has reasonable design and compact structure, solves the problems of easy tire burst, poor anti-skid effect and insufficient stiffness of the prior pneumatic tire, particularly the tire of an electric vehicle and a motorcycle, adopts the foaming tire core to replace the traditional pneumatic tire, prevents the tire burst and prolongs the service life of the tire.)

1. An integrally vulcanized non-pneumatic tire without steel wires and cord fabric, which comprises a tire and is characterized in that,

the tire is sequentially provided with a tire body outer layer (58), a cross-linking layer (54) and a tire core foaming layer (55) from outside to inside along the radial direction;

the tire body outer layer (58) and the tire core foaming layer (55) are in tight cross-linking fusion connection through the cross-linking layer (54), and the tire body outer layer (58), the cross-linking layer (54) and the tire core foaming layer (55) are in an integrally vulcanized inflation-free rubber tire structure finally formed by adopting two foaming strips (20) and strip tire fabrics (10) made of different materials through compounding and vulcanization molding processes;

wherein, a plurality of main upright columns (62) and auxiliary upright columns (63) which are arranged at intervals are annularly distributed on both sides of a tyre body outer layer (58).

2. A steel cord and cord fabric-free integrally vulcanized non-pneumatic tire as claimed in claim 1, wherein a secondary upright is formed between adjacent main uprights, the main uprights (62) have a trapezoidal structure with arc-shaped edges at both sides, the main uprights (62) are smoothly transited to the carcass of the carcass outer layer, and the arc-shaped recesses of the secondary uprights (63) are arranged on the carcass of the carcass outer layer.

3. A composite foamed non-pneumatic rubber tire according to claim 2, wherein the curvature of the concavity of said sub-pillar (63) is between 10 ° and 40 °.

4. A wireless and cord fabric integrated vulcanization non-pneumatic tire as in claim 1, wherein the core foam layer (56) has a plurality of independent and closed fine closed cells (55) therein, and the core foam layer is foamed to form a central cell (57).

5. A unitarily vulcanized non-pneumatic tire without cords and cord fabric as in claim 4, wherein said central hole (57) has a diameter of not less than 2 mm.

6. A unitarily vulcanized non-pneumatic tire without cords and cords as recited in claim 1, wherein said foam strip is a foam strip (20) in which a foam is extruded into a hollow strip shape by a rubber extruder.

7. The integrally vulcanized non-pneumatic tire without steel wires and cord fabric as claimed in claim 6, wherein the specific compounding process comprises: the foaming strip (20) is placed at an inlet (41) of a compound machine (40) connected with a rubber extruder and is inserted into a cavity (42) at the center of the foaming strip, the strip-shaped tire fabric (10) is placed at an inlet (31) of the rubber extruder (30), the strip-shaped tire fabric (10) is gradually formed into a dough shape from a strip shape under the pushing of a screw rod (61) of the rubber extruder (30) and enters the cavity (42) of the compound machine (40) communicated with the rubber extruder, then a conical cavity structure (44) is arranged at the position of an inner cavity of the compound machine close to an outlet (43), the dough-shaped tire fabric (10) tightly wraps the outer circle of the foaming strip (20) arranged in the cavity (42) under the pushing action of the conical structure of the compound machine and the screw rod of the extruder, the tire tread material (10) and the foaming strip (20) are extruded out of the compound machine after being compounded under the continuous pushing of the screw rod (61) of the rubber extruder, the composite rubber pipe (59) compounded by more than two times of the two different mixed rubber materials is formed.

8. The integrally vulcanized non-pneumatic tire without steel wires and cord fabric as claimed in claim 7, wherein the vulcanization molding process comprises cutting the composite hose and butt-joining the two ends together to form an annular tubular composite tire blank; wherein, the composite tire blank structure comprises a tread rubber (51) and a tire core rubber (52) which are distributed from outside to inside, and a composite interface layer (53) is formed between the tread rubber and the tire core rubber;

then putting the composite tire blank into an integrated vulcanizing machine, keeping the pressure of the inside of the integrated vulcanizing machine by controlling the vulcanizing temperature and the vulcanizing time, and after die assembly, firstly applying air pressure to the inside of the integrated vulcanizing machine, controlling the vulcanizing time, under the pressure and the temperature, firstly forming a tread pattern on the tread rubber (51) according to the lines of a die, forming a main upright post (62) and an auxiliary upright post (63) at intervals on two sides of a tire body, then transferring the temperature inwards, mutually vulcanizing the two different mixed rubber materials of the tread rubber (51) and the tire core rubber (52) and generating a crosslinking reaction to form a crosslinking layer (54), and under the transfer of the die temperature, vulcanizing and foaming the tire core rubber material to form a foamed tire core layer (56), thus finishing the manufacture of the inflation-free tire, and finally opening the die to take out the molded integrated vulcanized tire.

Technical Field

The invention relates to the technical field of inflation-free rubber tire equipment, in particular to an integrally vulcanized inflation-free tire without steel wires and cord fabric.

Background

A tire is a ground-rolling circular ring-shaped elastic rubber article mounted on various vehicles or machines. The tires currently in use are generally pneumatic tires, and some tires are non-pneumatic tires.

These tires also have the following problems during use:

1. the tire is inflatable, easy to puncture and burst, and short in service life.

2. The stiffness of tire is not enough, and under the bearing state, the area of contact of tire and ground increases to lead to the frictional force increase, the rolling resistance is great, exempts from pneumatic tire simultaneously because the dead weight is great, more can aggravate the area of contact of tire and ground, still can increase the frictional force of tire and ground.

3. The conventional tire is inconvenient for the vehicle to run at night.

To this end, we propose a non-pneumatic rubber tire.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an integrally vulcanized non-pneumatic tire without steel wires and cord fabric, which overcomes the defects of the prior art, has reasonable design and compact structure, solves the problems that the existing pneumatic tire, particularly the tire of an electric vehicle and a motorcycle is easy to blow out, has poor anti-skid effect and insufficient stiffness, adopts a foaming tire core to replace the traditional pneumatic tire, prevents the tire from blowing out and prolongs the service life of the tire; meanwhile, the stiffness of the tire can be improved, and the practicability is high.

In order to achieve the purpose, the invention is realized by the following technical scheme:

an integrally vulcanized non-pneumatic tire without steel wires and cord fabric, which comprises a tire and is characterized in that,

the rubber tire is sequentially provided with a tire body outer layer, a cross-linking layer and a tire core foaming layer from outside to inside along the radial direction;

the outer tire body layer, the cross-linking layer and the tire core foaming layer are respectively made of foaming strips and strip-shaped tire tread materials made of two different materials and finally form an integrally vulcanized inflation-free rubber tire structure through compounding and vulcanization molding processes;

wherein, a plurality of main upright columns and auxiliary upright columns which are arranged at intervals are annularly distributed on both sides of a tyre body of the outer layer of the tyre body of the tyre.

Furthermore, a pair of stand columns is formed between the adjacent main stand columns, the main stand columns are of a trapezoidal structure with arc-shaped edges on two sides, the main stand columns are in smooth transition with the outer tire casing of the tire casing, and the arc-shaped depressions of the auxiliary stand columns are arranged on the outer tire casing of the tire casing.

Further, the radian of the concave part of the auxiliary upright post is between 10 and 40 degrees.

Furthermore, a plurality of mutually independent and closed tiny closed holes are formed in the tire core foaming layer, and a central hole is formed after the tire core foaming layer is foamed.

Further, the diameter of the central hole is not less than 2 mm.

Further, the foamed strip is a foamed strip in which a foamed material is extruded into a hollow strip shape by a rubber extruder.

Further, the specific compounding process is as follows: the foaming strip is placed at an inlet of a compound machine connected with a rubber extruder and is inwards inserted into a cavity in the center of the compound machine, the strip-shaped tire fabric is placed at the inlet of the rubber extruder, the strip-shaped tire fabric is gradually formed into a dough from strips under the pushing of a screw rod of the rubber extruder and enters the cavity of the compound machine communicated with the rubber extruder, then a conical cavity structure is arranged in the inner cavity of the compound machine close to the outlet, the extrusion force generated by the dough-shaped tire fabric under the thrust action of the conical structure of the compound machine and the screw rod of the extruder tightly wraps the excircle of the foaming strip arranged in the cavity, and under the continuous pushing of the screw rod of the rubber extruder, the tire tread material and the foaming strip are compounded and then extruded out of the compound machine to form the compound rubber tube with more than two layers compounded by more than two different mixed.

Further, the vulcanization molding process comprises the steps of cutting the composite rubber tube, and carrying out butt joint, closing and hot bonding on two ends of the composite rubber tube to form an annular tubular composite tire blank; the composite tire blank structure comprises a tread rubber and a tire core rubber which are distributed from outside to inside, and a composite interface layer is formed between the tread rubber and the tire core rubber;

and then placing the composite tire blank into an integrated vulcanizing machine, controlling the vulcanizing temperature and the vulcanizing time, firstly applying air pressure to the inside of the integrated vulcanizing machine for pressure maintaining after die assembly, controlling the vulcanizing time, firstly forming tread patterns on the surface rubber according to the lines of the die at the pressure and the temperature, forming a main upright post and an auxiliary upright post which are spaced at two sides of the tire body, then transferring the temperature inwards, starting mutual vulcanization of two different mixed rubber materials, namely the tread rubber and the tire core rubber and generating a cross-linking reaction to form a cross-linking layer, starting vulcanization and foaming of the tire core rubber material under the transfer of the die temperature to form a tire core foaming layer, completing the manufacture of the non-pneumatic tire, and finally opening the die to take out the molded integrated vulcanized tire.

The invention has the beneficial effects that:

the embodiment of the invention provides a production and manufacturing process of an integrally vulcanized non-pneumatic tire without steel wires and cord fabric. The method has the following beneficial effects:

1. the bearing capacity can be improved, the tire tread is full and elastic, the stress is more uniform, and the dynamic balance effect is improved.

2. All be provided with the casing king post between two casing subpillars, the casing king post can provide the fore-and-aft holding power of tire, improves the bearing effect of tire then, improves the stiffness of tire, improves the elasticity of tire then.

3. The foaming strip can be more closely contacted with the tread material, and the separation and the peeling are prevented. Under the vulcanization effect of the vulcanizing agent at the same sulfur point, the outer surface of the foaming strip and the inner wall of the tire tread material are vulcanized and then cross-linked and fused, so that the contact effect is improved, and the separation is prevented.

4. The foaming material with the main component of the regenerated rubber is adopted, so that the overall price of the tire is reduced, the resource recycling is realized, the environment is protected, and the economic cost can be reduced.

5. Because the foaming material is adopted to replace the traditional inflatable inner tube, the risk of tire burst is avoided.

6. The flame retardant is added into the foaming material and the tire fabric, so that the flame retardant effect is improved, the safety performance is improved, the tire fabric is conveniently applied to the field of military industry, and meanwhile, the rubber plastic and the fiber material are added into the tire fabric, so that the mechanical strength and the tearing strength are improved, the bearing capacity is improved, the tire fabric is suitable for large-scale mechanical equipment, and the application range is enlarged.

7. Foaming and crosslinking are carried out in the same time of vulcanization, so that the production efficiency of the tire is improved.

8. Because the tire core foaming layer is internally provided with a plurality of mutually independent and closed holes, the tire can realize the anti-pricking and anti-explosion effects when meeting poor road surface environment.

9. The foaming inflation-free tire has no cord fabric or steel wire (the existing tire and the inflation-free tire have the structure), so the manufacturing process is obviously simplified, more personnel stations and energy consumption of operation are saved, and the foaming inflation-free tire can be recycled at 100 percent high efficiency after being crushed and desulfurized because the foaming inflation-free tire is a composite and crosslinked finished product of two rubber materials, and is more environment-friendly compared with the existing tire containing the steel wire and the cord fabric.

Drawings

FIG. 1 is a schematic cross-sectional view of a tire of the present invention after molding.

FIG. 2 is a schematic view of the process of the present invention.

FIG. 3 is a schematic illustration of the manufacture of the composite compound of the present invention.

FIG. 4 is a schematic view of the composite hose of the present invention.

FIG. 5 is a schematic representation of the cross-linking process of the present invention.

Detailed Description

The invention is further illustrated by the following specific figures and examples.

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.

A composite foaming inflation-free rubber tire is provided with a tire body outer layer 58 and a tire core foaming layer 56 in sequence from outside to inside along the radial direction; the outer tire body layer 58 and the foamed tire core layer 56 form an integrated tire structure through compounding and crosslinking processes, wherein a central hole 57 is formed in the foamed tire core layer 56.

The tire core foaming layer 56 is internally provided with a plurality of closed holes 55 which are independent and closed, when a tire runs to a road surface containing nails or sharp objects in the running process, the nails can only embed and influence the action parts due to the independence among the closed holes, the surrounding tire structure can not be influenced by the action of the nails, when the nails are pulled out, the tire has good stiffness due to the elasticity of the tire and the support of a plurality of air holes and can not influence the service performance of the whole tire, the closed holes are of a circular, oval or special-shaped hole structure, the size and the dimension of the holes are controlled within 3mm, the diameter of a central hole 57 formed after the tire core foaming layer is controlled to be more than 2mm, or the diameter of the central hole can be reduced to 0mm according to the foaming condition.

The outer child root of including the child hat in proper order under to of matrix, the casing of both sides and being connected with wheel hub, the outer 58 casing both sides of matrix both sides of rubber tire all ring shape distribute have a plurality of intervals main pillar 62 and the auxiliary pillar 63 of arranging, and the main pillar is the trapezium structure that has both sides arc edge, forms a pair stand between the adjacent main pillar, and wherein the main pillar flushes with the side plane of casing, the auxiliary pillar is sunken to be set up on the casing lateral wall. The main upright post 62 is in a trapezoidal structure with arc-shaped edges at two sides, the main upright post 62 and the carcass on the outer layer of the carcass are in smooth transition, the arc-shaped recess of the auxiliary upright post 63 is arranged on the carcass on the outer layer of the carcass, and the radian of the recess of the auxiliary upright post 63 is between 10 and 40 degrees.

As shown in fig. 1, after the tire bears a load, the tire can receive the pressure of a wheel hub and the reaction force F of the ground, the inner foamed tire core is converted into a tensile force after receiving the bidirectional pressure, and drives the foamed tire core to stretch towards two sides, meanwhile, the auxiliary upright post in a cambered surface is converted into a tensile force F1 which can move towards the foamed tire core after receiving the bidirectional pressure, so that the tensile force F2 of the foamed tire core is opposite to the tensile force generated by the depression of the auxiliary upright post of the tire body, the stretching amount of the foamed tire core can be reduced, the stiffness of the foamed tire core can be improved, after the stiffness of the foamed tire core is improved, the elasticity of the tire can be improved, the contact with the ground is reduced, the moving resistance is reduced, and after the transverse tensile force of the foamed tire core is reduced, the foamed tire core can be prevented from being damaged, and the service life of the foamed tire core.

Referring to the attached figures 1-5, the motor is 60, the motor provides driving force for the screw 61, and the production and manufacturing process of the composite type foaming inflation-free rubber tire comprises the following steps:

step one S1, preparing a foaming material: the method is characterized in that the regenerated rubber is taken as a main body (100 parts), meanwhile, the natural rubber (10 parts), the foaming agent (4 parts), the rubber auxiliary agent (8 parts) and the vulcanizing agent (3 parts) are added on rubber mixing equipment, and the raw materials are mixed and prepared into a strip-shaped foaming material at the temperature of 150-170 ℃ and under the air pressure of 0.5-1 MPa for later use.

Step two S2, manufacturing the tire fabric: the strip tire fabric 10 is prepared by plasticating and mixing 60 parts of natural rubber, 40 parts of synthetic rubber, 8 parts of rubber auxiliary agent, 3.5 parts of rubber plastic and 3 parts of vulcanizing agent on rubber mixing equipment at the temperature of 150-170 ℃ and the air pressure of 0.5-1 MPa, wherein the rubber plastic adopts high styrene and can improve the mechanical strength and the tearing strength of the tire.

Step three S3, manufacturing the foaming strip: extruding the foaming material prepared in the step I S1 into a hollow strip-shaped foaming strip 20 through a rubber extruder; the blowing agent in the foam strip of this step does not react.

Step four S4, preparing a composite sizing material:

placing the foaming strip 20 prepared in the step three into an inlet 41 of a compound machine 40 connected with a rubber extruder, inserting the foaming strip into a cavity 42 at the center of the foaming strip, setting the temperature in the compound machine at 60-120 ℃,

the strip-shaped tire fabric 10 is put into an inlet 31 of a rubber extruder 30, the strip-shaped tire fabric 10 is gradually formed into a dough shape from a strip shape under the pushing of a screw 61 of the rubber extruder 30 and enters a cavity 42 of a compound machine 40 communicated with the rubber extruder, then a conical cavity structure is arranged in an inner cavity of the compound machine close to an outlet 43, the dough-shaped tire tread material 10 generates an extrusion force under the thrust action of the conical structure of the compound machine and the screw of the extruder to tightly wrap the outer circle of a foaming strip 20 arranged in the cavity 42, and the tire tread material 10 and the foaming strip 20 are extruded out of the compound machine after being compounded under the continuous pushing of the screw 61 of the rubber extruder to form more than two layers of the compound rubber pipes 59 which are compounded by different mixed rubber materials for two times and are in a special shape or a round hollow strip shape;

step five S5, manufacturing a blank of the composite type foamed rubber tire: the irregular hollow strip-shaped composite sizing material prepared in the step four S4 is cut to the correct length on a cutting device according to the requirement,

step S6, hot bonding:

placing the composite rubber tube cut in the step 4 into a hot-joining machine, heating, butting and closing the two ends of the rubber tube through hot-joining equipment after accurately positioning and clamping the two ends of the rubber tube to form an annular tubular composite tire blank, wherein a tread rubber 51 and a tire core rubber 52 are distributed on the composite tire blank from outside to inside in a structure, and a composite interface layer 53 is formed between the tread rubber 51 and the tire core rubber 52;

step seven S7, tire vulcanization molding:

heating the inside of the combined-pressing type tire mold to 155-175 ℃, setting the air pressure at 6-18 MPa, and then putting the prepared composite tire blank into the combined-pressing type tire mold for integrated vulcanization, wherein the vulcanization time is controlled within 50 minutes.

In the process of integrated vulcanization: according to the production requirements of tires with different specifications, a tire crown, a tire body and a tire root are filled in the whole inner wall of a tire mold to form a fully-closed rubber tire;

in the process of integrated vulcanization: under the condition that the foaming strip is continuously heated, the foaming agent in the foaming strip begins to foam gradually and finally fills the inner cavity of the whole tire to form a solid or leave a few vacant sites, the foaming multiplying power of the foaming material with the main component of the regenerated rubber is stable and convenient to control during foaming, and the foaming strip is tightly attached to the tire fabric, so that the force applied to the tire fabric is more uniform in the foaming process, and the tire tread is fuller and has elasticity; the performance of the tire can be determined according to the foaming time of the foaming strips, when the foaming time of the foaming strips is longer, the inner cavity of the tire is in a solid state, the bearing capacity can be improved, when the foaming time of the foaming strips is shorter, a few vacant positions are reserved in the inner cavity of the tire, the bearing capacity is slightly reduced, and the elastic performance can be improved;

in the process of integrated vulcanization:

the tread rubber 51 forms tread patterns according to the lines of the mold, and forms a main column 62 and an auxiliary column 63 at intervals on two sides of the tire casing, and the specific integrated crosslinking process is as follows: as the temperature is transmitted from the outside to the inside along the radial direction of the mold, the tread rubber 51 starts to be vulcanized, when the hot temperature of the mold is transmitted to the composite interface layer 53, the two different mixed rubber materials of the tread rubber 51 and the tire core rubber start to be vulcanized with each other and generate a crosslinking reaction, a crosslinking layer 54 is formed, the air pressure is released after 5-15 minutes, the temperature is continuously transmitted to the tire core rubber inwards, the tire core rubber starts to be vulcanized and foamed under the transmission of the mold temperature, the foaming agent in the tire core rubber starts to be decomposed and foamed under the action of the mold temperature, the foaming agent in the tire core rubber starts to be decomposed and foamed, the tire core rubber forms a tire core foaming layer 56 under the wrapping of the three-dimensional netted polymer, the integrated crosslinking of the non-pneumatic tire is completed, and the molded tire forms a main upright column 62 and an auxiliary upright column 63 at two sides of a tire body according to the mold. Finally, the mold is opened to remove the molded tire. In fig. 5, the arrow indicates the temperature transfer direction.

By utilizing the common property of the rubber between the foaming strip in the step three S3 and the tire fabric in the step two S2, the rubber and the rubber can be crosslinked and fused together through the vulcanization effect of a vulcanizing agent at a certain temperature, the connection effect is improved, and therefore the integrated composite foaming inflation-free rubber tire is formed, the foaming strip and the tire tread material are combined more tightly, and separation and stripping are prevented.

Opening the mold: and after the step seven of integrated vulcanization, opening the mold and taking out the finished tire product.

In this embodiment, the foaming material in the first step S1 further includes a flame retardant, which has a flame retardant effect, improves safety performance, and is conveniently applied to the military field.

In this embodiment, the tread material in step two S2 further includes a fiber material and a flame retardant, the flame retardant is added to the tire fabric to improve the safety performance again, so as to prevent the tire fabric from being damaged by burning, and meanwhile, the strength of the tread can be improved and the bearing capacity can be improved by adding the fiber material.

Foaming strip and tread material are compounded together through the compounding machine and form multilayer (at least two-layer) compound sizing material, then vulcanize through subsequent integration and form the tire, and machining efficiency is high, makes foaming strip and tread material combine inseparabler more simultaneously and be difficult for droing, and the convenient control of foaming multiplying power makes the tire dynamic balance effect better, and the bearing capacity is higher, owing to adopt the foaming material of principal ingredients for reclaimed rubber, makes the economic cost of tire lower simultaneously, also environmental protection more simultaneously.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

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.