Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides the coffee machine integrating storage, crushing and extraction of coffee beans, which is convenient for coffee making, so that a better coffee taste is obtained, and the quality of coffee is improved.
The purpose of the invention is realized by the following technical scheme:
a coffee maker, comprising: the coffee extracting device, the coffee bean storing device and the coffee bean crushing device; the coffee extracting device is provided with a support frame, the coffee bean storage device is arranged on the support frame, and the coffee bean crushing device is arranged on the support frame;
the coffee bean crushing device comprises a fixed base and a containing vessel; the fixed base is provided with a driving assembly; the accommodating vessel is a hollow cavity structure with an opening at one end and a closed end, and the closed end of the accommodating vessel is provided with a crushing cutter component;
the drive assembly includes: the heat dissipation device comprises a driving motor, a driving rotating shaft, a heat dissipation rotating shaft, a driving clamping block and heat dissipation fan blades; the driving motor is provided with two output ends, one output end is in driving connection with the driving rotating shaft, the other output end is in driving connection with the heat dissipation rotating shaft, the driving clamping block is arranged on the driving rotating shaft, and the heat dissipation fan blade is arranged on the heat dissipation rotating shaft;
the crushing cutter assembly includes: a crushing rotating shaft, a crushing cutter head and a crushing turntable; the crushing rotating shaft penetrates through the closed end of the accommodating vessel, the crushing cutter head and the crushing rotary disc are respectively arranged at two ends of the crushing rotating shaft, the crushing cutter head is accommodated in the hollow cavity of the accommodating vessel, and the crushing rotary disc is positioned outside the hollow cavity of the accommodating vessel; and the crushing rotary disc is provided with a crushing clamping groove clamped with the driving clamping block.
In one embodiment, the open end of the receiving vessel is provided with a sealing cap.
In one embodiment, a handle is arranged on the outer side wall of the containing vessel.
In one embodiment, a friction barrier strip is arranged on the wall of the hollow cavity for accommodating the vessel.
In one embodiment, the driving clamping block is in a gear-shaped block structure, and the crushing clamping groove is in a gear-shaped groove structure.
In one embodiment, the closed end of the accommodating vessel is provided with a positioning convex ring, the fixed base is provided with a positioning groove, the positioning convex ring is accommodated in the positioning groove, the positioning convex ring is provided with a positioning clamping groove, and the groove wall of the positioning groove is provided with a positioning clamping block clamped with the positioning clamping groove.
In one embodiment, the heat dissipation fan blade is in a disc-shaped structure.
In one embodiment, the heat dissipation fan blade includes a plurality of sub-fan blades, and the plurality of sub-fan blades are distributed in an annular array around the rotation axis of the heat dissipation rotating shaft.
The coffee machine is provided with the coffee extraction device, the coffee bean storage device and the coffee bean crushing device, wherein the coffee bean storage device is used for hermetically storing coffee beans so as to isolate air and moisture and keep the coffee beans in a dry state; the coffee bean crushing device is used for crushing coffee beans so that the coffee beans can be ground into coffee powder to be used; the coffee extraction device is used for extracting coffee powder to obtain coffee liquid for tasting.
According to the coffee machine, the coffee extraction device, the coffee bean storage device and the coffee bean crushing device are arranged independently and do not affect each other, the coffee bean storage device only stores coffee beans, the coffee bean crushing device only crushes the coffee beans, and the coffee extraction device only extracts coffee powder, so that steam generated in the coffee extraction process cannot be directly contacted with the coffee beans, the coffee beans are prevented from being influenced by humid air to cause the quality of the coffee beans to be reduced, and the storage effect of the coffee beans can be greatly improved and the quality of the prepared coffee is improved due to the structural design.
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
Referring to fig. 1, a coffee maker 10 includes: coffee extraction device 100, coffee bean storage device 200, coffee bean grinding device 300. The coffee extracting apparatus 100 is provided with a support frame 110, the coffee bean storage apparatus 200 is installed on the support frame 110, and the coffee bean pulverizing apparatus 300 is placed on the support frame 110.
The coffee bean storage device 200 is used for hermetically storing coffee beans so as to isolate air and moisture and keep the coffee beans in a dry state; the coffee bean pulverizing apparatus 300 is for pulverizing coffee beans so that the coffee beans can be pulverized into coffee powder to be used; the coffee extraction device 100 is used for extracting coffee powder to obtain coffee liquid for tasting. In the use process of the coffee maker 10, the coffee beans stored in the coffee bean storage device 200 are taken out, the number of the taken-out coffee beans is determined according to the actual situation, then the coffee beans are pulverized by the coffee bean pulverizing device 300, and finally the pulverized coffee powder is extracted by the coffee extracting device 100, so that the coffee is made.
The coffee machine 10 of above-mentioned structure, coffee extraction device 100, coffee bean storage device 200, coffee bean reducing mechanism 300 sets up independently separately, each other does not influence, coffee bean storage device 200 only stores the processing to coffee bean, coffee bean reducing mechanism 300 only carries out shredding to coffee bean, coffee extraction device 100 only carries out extraction processing to coffee powder, therefore, produced aqueous vapor can not directly contact with coffee bean in the coffee extraction process, avoided coffee bean to receive humid air's influence and make its quality descend, such structural design, can greatly promote the storage effect of coffee bean, promote the quality of the coffee that makes.
It can be seen that the coffee bean pulverizing apparatus 300 serves as a link for connecting the coffee bean storing apparatus 200 and the coffee extracting apparatus 100. Therefore, how to optimize the structure of the coffee bean pulverizing apparatus 300 so that the coffee bean pulverizing apparatus 300 is better connected to the coffee bean storing means 200 and the coffee extracting means 100 is a technical problem to be solved.
The following describes a specific structure of the coffee bean grinding apparatus 300 and a connection relationship between the respective members:
referring to fig. 2, 3, 4 and 5, the coffee bean pulverizing apparatus 300 includes a fixed base 310 and a receiving vessel 320. The fixed base 310 is provided with a driving component 330; the receiving vessel 320 has a hollow cavity structure with an open end and a closed end, and the closed end of the receiving vessel 320 is provided with a crushing cutter assembly 340. Specifically, the fixing base 310 is fixed on the supporting frame 110, and the accommodating vessel 320 is removably and movably disposed on the fixing base 310. The receiving vessel 320 is used for collecting coffee beans, the driving assembly 330 disposed on the fixing base 310 is used for driving the pulverizing cutter assembly 340, and the coffee beans in the receiving vessel 320 are pulverized by the action of the pulverizing cutter assembly 340.
Referring to fig. 6, in particular, the driving assembly 330 includes: the driving motor 331, the driving rotating shaft 332, the heat dissipation rotating shaft 333, the driving fixture block 334 and the heat dissipation fan blade 335. The driving motor 331 has two output terminals, one of the output terminals is drivingly connected to the driving shaft 332, the other output terminal is drivingly connected to the heat dissipating shaft 333, the driving latch 334 is disposed on the driving shaft 332, and the heat dissipating fan 335 is disposed on the heat dissipating shaft 333.
Referring to fig. 7 and 8, the crushing cutter assembly 340 includes: a crushing rotating shaft 341, a crushing cutter head 342 and a crushing rotary disc 343. The crushing rotating shaft 341 penetrates through the closed end of the accommodating vessel 320, the crushing cutter head 342 and the crushing turntable 343 are respectively arranged at two ends of the crushing rotating shaft 341, the crushing cutter head 342 is accommodated in the hollow cavity of the accommodating vessel 320, and the crushing turntable 343 is positioned outside the hollow cavity of the accommodating vessel 320; the crushing rotary disc 343 is provided with a crushing clamping groove 344 clamped with the driving clamping block 334. In this embodiment, the driving block 334 is a gear-shaped block structure, and the pulverizing slot 344 is a gear-shaped groove structure.
The operation principle of the coffee bean grinder 300 having the above-described structure will be described below:
taking an appropriate amount of coffee beans from the coffee bean storage device 200 into the hollow cavity of the receiving vessel 320;
the accommodating vessel 320 is inserted into the fixed base 310, and at this time, the driving fixture block 334 is clamped into the crushing clamp groove 344 of the crushing turntable 343;
the driving motor 331 is started, the driving motor 331 drives the driving rotating shaft 332 to rotate, the driving rotating shaft 332 further drives the driving clamping block 334 to rotate, the driving clamping block 334 further drives the crushing rotating disc 343 to rotate, the crushing rotating disc 343 further drives the crushing rotating shaft 341 to rotate, and the crushing rotating shaft 341 in rotation realizes the rotation of the crushing cutter head 342, so that the coffee beans in the hollow cavity of the accommodating vessel 320 can be crushed;
after the coffee beans are pulverized into coffee powder, the pulverized coffee powder can be poured into the coffee extraction device 100, and the coffee extraction device 100 extracts the coffee powder to obtain coffee liquid.
It should be noted that, when the driving motor 331 is started to operate, the driving motor 331 further drives the heat dissipation fan blade 335 to rotate through the heat dissipation rotating shaft 333, and the heat dissipation fan blade 335 disturbs the airflow, so as to achieve heat dissipation of the driving motor 331 and prevent heat accumulation from leading to burning out of the motor. Referring to fig. 6, specifically, the heat dissipation fan 335 has a disc-shaped structure, and the heat dissipation fan 335 includes a plurality of sub-fan blades, and the plurality of sub-fan blades are distributed in a ring-shaped array around the rotation axis of the heat dissipation rotation shaft 333.
Referring to fig. 2, in the embodiment, a sealing cover 321 is disposed at an opening end of the receiving vessel 320, and the coffee beans can be prevented from splashing out during the grinding process by the sealing cover 321; referring to fig. 5, a handle 322 is disposed on an outer sidewall of the receiving vessel 320, and the receiving vessel 320 can be better grasped by the handle 322.
Referring to fig. 4, in particular, a friction barrier 323 is disposed on a wall of the hollow cavity of the receiving vessel 320, and the friction barrier 323 has the following effects: on one hand, the friction blocking strip 323 can effectively block coffee beans in the accommodating vessel 320, and the grinding cutter head 342 is effectively matched, so that the coffee beans can be better ground under the friction and blocking of the friction blocking strip 323; on the other hand, the coffee beans disturbed by the grinding cutter head 342 collide with the friction blocking strip 323, so that the coffee beans jump, thereby being more beneficial to grinding the coffee beans; on the other hand, the friction blocking strip 323 also has the function of a reinforcing rib, so that the overall structural strength of the accommodating vessel 320 is better, and the accommodating vessel is not easy to deform.
Referring to fig. 7 and 8, further, the crushing cutter head 342 includes an upper top cutter 3421 and a lower bottom cutter 3422, the upper top cutter 3421 extends toward the opening end of the container 320, and the lower bottom cutter 3422 extends toward the closing end of the container 320. Because one end of the pulverizing spindle 341 protrudes from the closed end of the container 320, the lower bottom knife 3422 is especially provided for pulverizing the coffee beans in the space, and the lower bottom knife 3422 pulverizes the coffee beans in the space, thereby reducing the pulverizing blind area and enabling the coffee beans to be pulverized comprehensively. In this embodiment, the upper top knife 3421 has a "U" shape, and the lower bottom knife 3422 has a "U" shape.
Referring to fig. 3 and 5, in order to accurately insert the receiving vessel 320 onto the fixing base 310, a positioning convex ring 324 is disposed at the closed end of the receiving vessel 320, a positioning groove 311 is disposed on the fixing base 310, the positioning convex ring 324 is received in the positioning groove 311, a positioning groove 3241 is disposed on the positioning convex ring 324, and a positioning block 3111 engaged with the positioning groove 3241 is disposed on a groove wall of the positioning groove 311. Thus, by accommodating the positioning convex ring 324 in the positioning groove 311, the positioning fixture block 3111 is clamped in the positioning fixture groove 3241, so that the accommodating vessel 320 can be accurately inserted into the fixing base 310.
The coffee bean storage apparatus 200 serves to hermetically store coffee beans to exclude air and moisture and maintain the coffee beans in a dry state. When it is necessary to crush the coffee beans, it is necessary to take out the coffee beans from the coffee bean storage 200. It is understood that the coffee bean storage apparatus 200 is required to have not only a function of storing coffee beans but also a function of facilitating taking out of coffee beans. Therefore, how to optimally design the structure of the coffee bean storage device 200 is to improve the storage effect of the coffee beans on one hand and to conveniently take out the coffee beans from the storage device on the other hand, which is a technical problem to be solved by research and development personnel.
The following describes a specific structure of the coffee bean storage apparatus 200 and a connection relationship between the respective members:
referring to fig. 9 and 10, the coffee bean storage apparatus 200 includes: coffee bean storage jar 210, fixed establishment 220, movable establishment 230. Here, it is to be noted that the coffee bean storage tank 210 is for storing coffee beans; the fixing mechanism 220 is mainly used for realizing the fixing function, and the fixing mechanism 220 is fixed on the support frame 110, so that the whole coffee bean storage device 200 is fixed; the movable mechanism 230 is mainly used for achieving the function of a switch, and the purpose of opening and closing is achieved by rotating the movable mechanism 230, so that the coffee beans are taken and used.
Referring to fig. 9, the coffee bean storage tank 210 is a hollow tank structure with one open end and one closed end. The coffee bean storage tank 210 is used to store coffee beans.
Referring to fig. 11, the fixing mechanism 220 is a disk structure, an annular groove 221 is formed on an end surface of the fixing mechanism 220, and an opening end of the coffee bean storage tank 210 is inserted into the annular groove 221 of the fixing mechanism 220. Like this, in other words for coffee bean storage jar 210 has added a lid, the open end of coffee bean storage jar 210 is sealed to fixed establishment 220 shutoff coffee bean, and the coffee bean is difficult to come out, only through the effect of switch, can realize taking of coffee bean.
Referring to fig. 12, the movable mechanism 230 includes: coffee bean blanking drainage piece 231, coffee bean blanking switch piece 232 and coffee bean blanking knob piece 233.
The coffee bean blanking drainage piece 231 is of a conical structure, and the coffee bean blanking drainage piece 231 is accommodated in a hollow cavity of the coffee bean storage tank 210; the side wall of the coffee bean blanking drainage part 231 is provided with a clamping hole 2311, the coffee bean blanking switch part 232 is of a disc body structure, the middle part of the disc body of the coffee bean blanking switch part 232 is provided with a positioning cylinder 234, the positioning cylinder 234 is provided with a buckle 2341, the middle part of the disc body of the fixing mechanism 220 is provided with a positioning hole 222 (shown in fig. 11), the positioning cylinder 234 penetrates through the positioning hole 222, and the buckle 2341 is clamped on the clamping hole 2311; the coffee bean blanking drainage member 231 abuts against one end face of the fixing mechanism 220, and the coffee bean blanking switch member 232 abuts against the other end face of the fixing mechanism 220.
The side wall of the coffee bean blanking drainage piece 231 forms a drainage inclined surface 2312, a blanking through hole 223 (as shown in fig. 11) is formed in the edge of the disk body of the fixing mechanism 220, and a switch through hole 2321 is formed in the edge of the disk body of the coffee bean blanking switch piece 232. The coffee bean blanking drainage piece 231 is provided with a stirring gear disc 235.
The coffee bean blanking knob 233 is a hollow cavity structure with two open ends, a clamping buckle 2331 is arranged at one open end of the coffee bean blanking knob 233, a clamping hole 2322 is arranged at the edge of the plate body of the coffee bean blanking switch 232, and the clamping buckle 2331 is clamped in the clamping hole 2322.
Next, the procedure of installing the coffee bean storing apparatus 200 will be described:
firstly, the coffee bean blanking rotary knob member 233 and the coffee bean blanking switch member 232 are assembled, specifically, as one opening end of the coffee bean blanking rotary knob member 233 is provided with the clamping buckle 2331, and the edge of the disk body of the coffee bean blanking switch member 232 is provided with the clamping hole 2322, the clamping buckle 2331 is clamped in the clamping hole 2322, thus, the coffee bean blanking rotary knob member 233 is buckled on the coffee bean blanking switch member 232;
then, the coffee bean blanking switch 232 and the coffee bean blanking drainage piece 231 are assembled, specifically, the middle of the disk body of the fixing mechanism 220 is provided with a positioning hole 222, the middle of the disk body of the coffee bean blanking switch 232 is provided with a positioning cylinder 234, the positioning cylinder 234 penetrates through the positioning hole 222, and as the side wall of the coffee bean blanking drainage piece 231 is provided with a clamping hole 2311, and the positioning cylinder 234 is provided with a buckle 2341, the buckle 2341 is clamped on the clamping hole 2311, so that the coffee bean blanking switch 232 is buckled on the coffee bean blanking drainage piece 231;
in the process of assembling the coffee bean blanking switch part 232 and the coffee bean blanking drainage part 231, the fixing mechanism 220 is limited between the coffee bean blanking switch part 232 and the coffee bean blanking drainage part 231, so that the fixing mechanism 220 is also indirectly assembled;
then, coffee beans are poured into the coffee bean storage tank 210, after the coffee beans are loaded, because the annular clamping groove 221 is formed in one end face of the fixing mechanism 220, the open end of the coffee bean storage tank 210 can be inserted into the annular clamping groove 221 of the fixing mechanism 220, and therefore the coffee bean storage tank 210 and the fixing mechanism 220 can be assembled;
finally, the coffee bean storage device 200 loaded with coffee beans is integrally mounted on the supporting frame 110, specifically, the supporting frame 110 is provided with the supporting ring 111 (as shown in fig. 9), and the fixing mechanism 220 is clamped on the supporting ring 111, so that the coffee bean storage device 200 can be integrally fixed.
The operation principle of the coffee bean storage apparatus 200 will be explained below:
the coffee bean blanking knob member 233 is rotated, the coffee bean blanking knob member 233 further drives the coffee bean blanking switch member 232 connected with the coffee bean blanking knob member to rotate, when the coffee bean blanking switch member 232 rotates to a certain position, the switch through hole 2321 on the coffee bean blanking switch member 232 is communicated with the blanking through hole 223 on the fixing mechanism 220, so that coffee beans accommodated in the coffee bean storage tank 210 can sequentially pass through the blanking through hole 223 and the switch through hole 2321, and then fall into the accommodating vessel 320 from the hollow cavity of the coffee bean blanking knob member 233;
after a proper amount of coffee beans are collected in the receiving vessel 320, the coffee bean blanking knob 233 is rotated, so that the coffee bean blanking switch 232 is rotated to a certain position, the rest parts of the coffee bean blanking switch 232 block the blanking through hole 223, and then the switch through hole 2321 is not communicated with the blanking through hole 223, so that the coffee beans in the coffee bean storage tank 210 cannot fall off.
The following explains the principle of the structural design of the coffee bean storage apparatus 200:
1. the coffee bean blanking drainage piece 231 is of a conical structure, and the side wall of the coffee bean blanking drainage piece 231 forms a drainage inclined surface 2312, so that the drainage inclined surface 2312 can guide coffee beans in the coffee bean storage tank 210 to the blanking through hole 223, and the coffee beans are blanked by the blanking through hole 223 and the switch through hole 2321;
2. the coffee bean blanking drainage piece 231 is provided with the stirring gear disc 235, the coffee bean blanking knob 233 is rotated, the coffee bean blanking drainage piece 231 is driven to rotate by the coffee bean blanking switch 232, then the stirring gear disc 235 is also driven by the coffee bean blanking drainage piece 231 to rotate, and the rotating stirring gear disc 235 can stir the coffee beans in the coffee bean storage tank 210, so that the coffee beans can smoothly fall into the blanking through holes 223 by stirring the coffee beans, and the blanking smoothness is improved;
3. through the arrangement of the coffee bean blanking switch part 232, the coffee bean blanking switch part 232 makes rotary motion, and the rotary motion can simultaneously realize the following two functions, on one hand, the rotary coffee bean blanking switch part 232 can plug or penetrate the blanking through hole 223 to realize the blanking of coffee beans, and on the other hand, the rotary coffee bean blanking switch part 232 can drive the coffee bean blanking flow guide part 231 and the stirring gear disc 235 to rotate, so that the coffee beans are stirred, and the smoothness of the coffee bean blanking is improved;
4. the middle part of the disc body of the coffee bean blanking switch part 232 is provided with the positioning cylinder 234, the middle part of the disc body of the fixing mechanism 220 is provided with the positioning hole 222, and the positioning cylinder 234 penetrates through the positioning hole 222, so that on one hand, the coffee bean blanking drainage part 231, the fixing mechanism 220 and the coffee bean blanking switch part 232 can be accurately assembled, the fixing mechanism 220 is clamped between the coffee bean blanking drainage part 231 and the coffee bean blanking switch part 232, the fixing mechanism 220 supports the coffee bean blanking drainage part 231 and the coffee bean blanking switch part 232, and on the other hand, the coffee bean blanking drainage part 231 and the coffee bean blanking switch part 232 are also favorably connected with each other and realize rotation;
5. the blanking through hole 223 is formed in the edge of the disk body of the fixing mechanism 220, and the switch through hole 2321 is formed in the edge of the disk body of the coffee bean blanking switch member 232, so that the blanking through hole 223 and the switch through hole 2321 are not formed in the center of the disk body, and through or blocking between the through holes can be realized in a rotating mode through the structural design, and the purpose of coffee bean blanking is achieved;
6. the coffee bean blanking knob member 233 is a hollow cavity structure with two open ends, so that on one hand, the coffee bean blanking switch member 232 and the coffee bean blanking drainage member 231 can rotate by rotating the coffee bean blanking knob member 233, thereby saving labor, and on the other hand, the coffee beans in the coffee bean storage tank 210 can reach the accommodating vessel 320 by passing through the hollow cavity of the coffee bean blanking knob member 233, thereby realizing centralized guiding of the coffee beans.
It is noted that the agitation of the coffee beans by the agitation gear plate 235 is an essential action in the coffee bean dropping process. However, in the process of rotating the coffee bean blanking diversion member 231 and the coffee bean blanking switch member 232, only the blanking through hole 223 and the switch through hole 2321 are communicated with each other, so that the coffee beans can be blanked. It can be known that if only one blanking through hole 223 is opened, it is obviously difficult to satisfy the requirement of coffee bean blanking. Referring to fig. 11, in particular, a plurality of blanking through holes 223 are formed at the edge of the tray body of the fixing mechanism 220, and the plurality of blanking through holes 223 are distributed in a ring-shaped array around the central axis of the fixing mechanism 220. Through setting up a plurality of blanking through-holes 223, at the in-process to the rotatory a week of coffee bean blanking switch spare 232, switch through-hole 2321 just needs to pass through a plurality of blanking through-holes 223 in proper order, and every through a blanking through-hole 223, coffee bean just can drop from one of them through-hole, like this, can greatly improve coffee bean's blanking efficiency, also greatly improved coffee bean's blanking smoothness nature, coffee bean is difficult to the card and dies.
The coffee machine 10 of the present invention is provided with a coffee extraction device 100, a coffee bean storage device 200, and a coffee bean grinding device 300, wherein the coffee bean storage device 200 is used for hermetically storing coffee beans so as to isolate air and moisture and keep the coffee beans in a dry state; the coffee bean pulverizing apparatus 300 is for pulverizing coffee beans so that the coffee beans can be pulverized into coffee powder to be used; the coffee extraction device 100 is used for extracting coffee powder to obtain coffee liquid for tasting.
According to the coffee machine 10, the coffee extraction device 100, the coffee bean storage device 200 and the coffee bean crushing device 300 are independently arranged and do not affect each other, the coffee bean storage device 200 only stores coffee beans, the coffee bean crushing device 300 only crushes coffee beans, and the coffee extraction device 100 only extracts coffee powder, so that moisture generated in the coffee extraction process cannot directly contact with the coffee beans, the coffee beans are prevented from being influenced by humid air to reduce the quality of the coffee beans, and the structural design can greatly improve the storage effect of the coffee beans and the quality of the prepared coffee.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.