Patent Grant
11585573
This application claims the priority to the Chinese Patent Application No. 202021208020.5, filed on Jun. 24, 2020, which is hereby incorporated by reference in its entirety.
The present disclosure relates to the field of gas mixing, in particular to a gas mixing device.
The present disclosure also relates to the field of water heating devices, in particular to a gas water heating device.
Fully premixed gas combustion refers to a combustion method in which gas is mixed with adequate air before entering the combustor, and no air is needed during the combustion. The flame propagation speed of fully premixed combustion is high, and the volumetric heat intensity of the combustion chamber is very high, generally up to 28˜56*103Kw/m2 or higher. Complete combustion can be achieved at a small excess air coefficient, and there is almost no chemical incomplete combustion phenomenon.
In a fully premixed gas water heater, a Venturi premixing device is generally used to ensure full mixing of fuel gas and air, making the air flow velocity field uniform, thereby ensuring that the air flow velocity at each point of the combustor is greater than the flame propagation velocity under the lowest load. At the same time, the uniformity of the flame on the surface of the combustor is ensured, thus the flame on the surface of the combustor is prevented from being too long and contacting the surface of the heat exchanger to cause incomplete combustion.
However, in general, the Venturi tube of the current fully premixed gas water has a relatively small regulation ratio of no more than 1:10, thus the problem that the water temperature is too high under a low load still exists, which, especially in summer, will reduce the user experience. Moreover, there is also a problem of unstable flue gas emission during power regulation.
In view of the above deficiencies, one purpose of the present disclosure is to provide a gas mixing device and a gas water heating device that can provide a higher regulation ratio, thereby solving the problem that the water temperature is too high in summer.
Another purpose of the present disclosure is to provide a gas mixing device and a gas water heating device that can improve the stability of flue gas emission during power regulation.
To achieve the above purposes, the present disclosure adopts the following technical solutions:
A gas mixing device, comprising:
a shell provided with a fuel gas channel for inputting fuel gas, an air channel for inputting air and a gas mixing channel, the fuel gas channel being provided with a first cut-off portion capable of changing a flow area, and the air channel being provided with a second cut-off portion capable of changing a flow area;
a moving part movable in the shell, the moving part simultaneously changing the flow areas of the first cut-off portion and the second cut-off portions by moving.
As a preferred embodiment, a movable contraction structure is provided in the shell; the air channel is located inside the contraction structure; the fuel gas channel is located outside the contraction structure; an internal flow area of the contraction structure gradually decreases in an air flow direction to form a contraction section; at least part of the internal flow area of the gas mixing channel gradually increases in an internal gas flow direction to form a diffusion section; and the fuel gas channel is communicated between the contraction section and the diffusion section.
As a preferred embodiment, a ratio of a maximum flow area to a minimum flow area of the first cut-off portion is 10 to 30; and a ratio of a maximum flow area to a minimum flow area of the second cut-off portion is 2 to 6.
As a preferred embodiment, the moving part moves linearly in the shell.
As a preferred embodiment, the moving part comprises an air cut-off plug and a throat that is disposed to sleeve the air cut-off plug; the contraction structure is provided on the throat; an outer wall of the throat and an inner wall of the shell are provided with sealing structures slidable relative to each other; the sealing structures seal and separate the air channel and the fuel gas channel; the air channel is located inside the throat; and the fuel gas channel is located outside the throat.
As a preferred embodiment, the shell is provided with a driving motor, which simultaneously drives the throat to move and drives the air cut-off plug to move relative to the throat, thereby simultaneously changing the flow areas of the first cut-off portion and the second cut-off portion.
As a preferred embodiment, the shell is provided with a gas mixing tube forming the gas mixing channel; the first cut-off portion is formed between the throat and an end portion of the mixing tube; and the second cut-off portion is formed between the throat and the air cut-off plug.
As a preferred embodiment, the air cut-off plug and the throat move synchronously in a predetermined transmission ratio.
As a preferred embodiment, the throat is connected to the air cut-off plug or a motor shaft of the driving motor through a transmission mechanism; the driving motor directly drives the air cut-off plug to move, and the air cut-off plug or the motor shaft of the driving motor causes the throat to move through the transmission mechanism.
As a preferred embodiment, the transmission mechanism is a linkage mechanism.
As a preferred embodiment, the transmission mechanism comprises a first linkage and a second linkage which are rotatably connected through a pivot shaft; wherein one end of the first linkage is rotatably connected to the air cut-off plug or the motor shaft of the driving motor, and one end of the second linkage is rotatably connected to the throat.
As a preferred embodiment, the driving motor is a linear motor; and the air cut-off plug is fixedly disposed to sleeve an output shaft of the linear motor.
As a preferred embodiment, the shell is provided therein with a guide mechanism defining a moving path of the pivot shaft; and when moving in the moving path, the pivot shaft causes the throat to move linearly.
As a preferred embodiment, the outer wall of the throat is provided with a first mating surface which participates in forming the first cut-off portion; the first mating surface has cambered surfaces with different radians in a moving direction of the throat; and the throat moves so that the cambered surfaces with different radians are respectively matched with the gas mixing tube to change the flow area of the first cut-off portion.
As a preferred embodiment, an upper end of the air cut-off plug is provided with a second mating surface which participates in forming the second cut-off portion; the second mating surface has surfaces with different radians in a moving direction of the air cut-off plug; and the air cut-off plug moves so that surfaces with different radians are respectively matched with an inner wall of the throat to change the flow area of the second cut-off portion.
As a preferred embodiment, the driving motor directly drives the throat and the air cut-off plug to move linearly.
As a preferred embodiment, an output end of the driving motor is provided with a first driving gear and a second driving gear which are coaxially disposed; the air cut-off plug is driven by the driving motor through a first rack and the first driving gear to mesh; the throat is driven by the driving motor through a second rack and the second driving gear to mesh; and an addendum circle diameter of the first driving gear is smaller than that of the second driving gear.
As a preferred embodiment, the shell is provided with a gas mixing tube forming the gas mixing channel; the moving part comprises an air cut-off plug and a throat that is disposed to sleeve the air cut-off plug;
the fuel gas channel is provided therein with a baffle plate; the baffle plate is provided with a flow hole which penetrates the baffle plate; the throat is fixedly provided with a shielding structure for shielding the flow hole; and the shielding structure moves to change a shielded area of the flow hole, so as to change the flow area of the first cut-off portion;
the air cut-off plug is fixedly provided with an air cut-off plate; the shell is provided with a variable-diameter portion; and the air cut-off plate and the variable-diameter portion move relative to each other to change the flow area of the second cut-off portion.
A gas water heating device, comprising the gas mixing device according to any one of the above embodiments.
The gas mixing device provided in one embodiment of the present disclosure simultaneously changes the flow areas of the first cut-off portion and the second cut-off portion by movement of the moving part, and simultaneously changes the input amount of fuel gas and of air while maintaining a mixing ratio between fuel gas and air to thereby change the amount of the mixed gas in the gas mixing channel. Therefore, the regulation ratio of the gas mixing device can be stably changed, and a stable flue gas emission can be achieved.
Particular embodiments of the present disclosure are disclosed in detail with reference to the descriptions and figures in the following, and the ways in which the principle of the present disclosure can be employed are pointed out. It should be appreciated that the embodiments of the present disclosure are not limited in scope thereby.
Features which are described and/or indicated for one embodiment can be used in one or more other embodiments in an identical or similar way, can be combined with features in the other embodiments, or can replace the features in the other embodiments.
It should be emphasized that the term “comprise/include”, when used in this text, refers to the presence of features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps or components.
In order to explain more clearly the technical solutions in the embodiments in the present disclosure or in the prior art, the following will briefly introduce the figures needed in the description of the embodiments or the prior art. Obviously, figures in the following description are only some embodiments of the present disclosure, and for a person skilled in the art, other figures may also be obtained based on these figures without paying any creative effort.
In order to enable persons skilled in the art to better understand the technical solutions in the present disclosure, a clear and comprehensive description to the technical solutions in the embodiments of the present disclosure will be given in the following in combination with the figures in the embodiments of the present disclosure, and obviously, the embodiments described are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by ordinary skilled persons in this field without paying any creative effort should pertain to the scope of protection of the present disclosure.
What needs to be explained is that, when an element is referred to as being “provided on” another element, it can be directly on the other element, or an intervening element may also be present. When an element is considered to be “connected to” another element, it can be directly connected to the other element, or an intervening element may also be present. The terms “perpendicular”, “horizontal”, “left” and “right” as well as similar expressions used in this text are only for the purpose of explanation, and do not represent a unique embodiment.
Unless otherwise defined, all technical and scientific terms used in this text have the same meaning as commonly understood by persons pertaining to the technical field of the present disclosure. The terminology used in the description of the present invention is for the purpose of describing the specific embodiments only, and is not intended to limit the present disclosure. The term “and/or” used in the text includes any and all combinations of one or more of the associated listed items.
Referring to
The gas mixing device provided by the present disclosure simultaneously changes the flow areas of the first cut-off portion 201 and the second cut-off portion 301 by movement of the moving part, and simultaneously changes the input amount of fuel gas and of air while maintaining a mixing ratio between fuel gas and air to thereby change the amount of the mixed gas in the gas mixing channel 400. Therefore, the regulation ratio of the gas mixing device can be stably changed, and a stable flue gas emission can be achieved.
The gas mixing device of this embodiment coordinately changes the fan speed during the change of the regulation ratio, so that the flue gas is stable. High regulation ratio solves the problem that the water temperature is too high in summer. A higher regulation ratio can be realized, lower power can be achieved, a more stable low-load combustion can be maintained.
The gas mixing device of this embodiment is a Venturi tube of a special structure. The air channel 300, the fuel gas channel 200 and the gas mixing channel 400 form the Venturi structure. Air flows through the air channel 300 towards the gas mixing channel 400, generating a negative pressure which forms suction of the fuel gas in the fuel gas channel 200.
To be specific, a movable contraction structure is provided in the shell 100. The contraction structure is a conical structure as a whole. The air channel 300 is located inside the contraction structure. The fuel gas channel 200 is located outside the contraction structure. An internal flow area of the contraction structure gradually decreases in an air flow direction to form a contraction section. At least part of the internal flow area of the gas mixing channel 400 gradually increases in an internal gas flow direction to form a diffusion section, and a mixed gas outlet 103 is formed at the tail end of it. The fuel gas channel 200 is communicated between the contraction section and the diffusion section. Between the contraction section and the diffusion section may be a throat having a flow area that is substantially unchanged in the flow direction. The fuel gas channel 200 is in communication with the throat.
In this embodiment, the moving part may be a single element, and may also be assembled from a plurality of elements. The moving part may comprise a plurality of elements driven directly or indirectly by a driving motor 500. The motion forms of the elements may be the same or different, and the present disclosure does not give limitations to this. The movement form of the moving part in the shell 100 may be rotation, translation and swing, and may even be a combination of a plurality of motions. In this embodiment, the moving part moves linearly in the shell 100. The driving motor 500 has a motor shaft, the moving part can be mounted on the motor shaft, and the moving part can move in an axial direction.
To be specific, the moving part comprises an air cut-off plug 20 and a throat 10 that is disposed to sleeve the air cut-off plug 20. The contraction structure is provided on the throat 10. The contraction structure is a part of the throat 10. The throat 10 can move to change the flow area of the first cut-off portion. The outer wall of the throat 10 and the inner wall of the shell 100 are provided with sealing structures slidable relative to each other. The sealing structures seal and separate the air channel 300 and the fuel gas channel 200. The air channel 300 is located inside the throat 10. The fuel gas channel 200 is located outside the throat 10. The sealing structure may comprise a sealing ring 150 provided on the outer wall of the lower end of the throat 10. The sealing ring 150 and the inner wall of the lower end of the upper shell 101 are fitted and sealed with each other. The throat 10 of a conical structure projects upwardly.
The shell 100 is provided with a gas mixing tube 30 forming the gas mixing channel 400. The upper end 11 of the throat 10 extends into the gas mixing tube 30. The throat 10 and the gas mixing tube 30 are coaxially provided. The first cut-off portion 201 is formed between the throat 10 and an end portion (the lower end) of the gas mixing tube 30. The second cut-off portion 301 is formed between the throat 10 (the inner wall) and the air cut-off plug 20 (the upper end 21). The first cut-off portion 201 is located at any position of the fuel gas channel 200, i.e. may be located at the tail end, entry end or even a middle position of the fuel gas channel 200. In this embodiment, the first cut-off portion 201 is substantially located at the tail end of the fuel gas channel 200, and fuel gas enters the gas mixing channel 400 after being discharged from the first cut-off portion 201. The second cut-off portion 301 is substantially located at the tail end of the air channel 300, and air enters the gas mixing channel 400 after being discharged from the second cut-off portion 301.
As shown in
In this embodiment, the side wall of the upper shell 101 has a gas side tube 110, which having a fuel gas inlet 104 for inputting fuel gas. The air channel 300 is located inside the throat 10. When facing
What needs to be explained is that the upward and downward orientations described in this embodiment are defined based on the orientation facing
In this embodiment, the shell 100 is provided with a driving motor 500. The driving motor 500 is fixedly mounted at the lower end of the shell 100. The driving motor 500 simultaneously drives the throat 10 to move and drives the air cut-off plug 20 to move relative to the throat 10, thereby simultaneously changing the flow areas of the first cut-off portion 201 and the second cut-off portion 301. To be specific, the driving motor 500 can directly drive the air cut-off plug 20 to move and indirectly drive the throat 10 (e.g., the throat 10 can be caused to move by means of the air cut-off plug 20), and can also directly drive the throat 10 to move and indirectly drive the air cut-off plug 20 (e.g., the air cut-off plug 20 can be caused to move by means of the throat 10). Of course, the driving motor 500 can also directly drive the air cut-off plug 20 and the throat 10 simultaneously.
The motions of the air cut-off plug 20 and the throat 10 may be the same, i.e. they move synchronously and equidistantly. That is, the air cut-off plug 20 and the throat 10 have the same speed when doing linear movements, and the transmission ratio between the two is 1:1. In this embodiment, the air cut-off plug 20 and the throat 10 move synchronously in a predetermined transmission ratio. To be specific, considering the mixing ratio between air and fuel gas, the moving speed of the air cut-off plug 20 may be greater than that of the throat 10. The change rate of the flow area of the first cut-off portion 201 may be greater than that of the second cut-off portion 301. The linear movements of the air cut-off plug 20 and the throat 10 are not equal in speed. The air cut-off plug 20 and the throat 10 move upwardly or downwardly together at different speeds to maintain a certain mixing ratio between fuel gas and air, thereby ensuring the stability of combustion.
In this embodiment, in order to realize the linear movements of the air cut-off plug 20 and the throat 10, the driving motor 500 can be a linear motor, and the air cut-off plug 20 is fixedly disposed to sleeve the output shaft (motor shaft) of the linear motor 500. The air cut-off plug 20 can be mounted on the output shaft of the linear motor 500 to perform a linear movement together with the output shaft. The air cut-off plug 20, when moving linearly, causes the throat 10 to move linearly as well.
In order to realize the movement of the throat 10, the throat 10 is connected to the air cut-off plug 20 or the motor shaft of the driving motor by means of a transmission mechanism. The driving motor 500 directly drives the air cut-off plug 20 to move, and the air cut-off plug 20 or the motor shaft of the driving motor causes the throat 10 to move by means of the transmission mechanism. As shown in
In this embodiment, the transmission mechanism is a linkage mechanism. To be specific, the transmission mechanism comprises a first linkage 41 and a second linkage 42 rotatably connected via a pivot shaft 43. One end of the first linkage 41 is rotatably connected to the air cut-off plug 20, and one end of the second linkage 42 is rotatably connected to the throat 10. In this embodiment, one end of the first linkage 41 may also be directly and rotatably connected to the motor shaft of the driving motor 500, in which case the throat 10 can also be caused to move by means of the transmission mechanism.
As can be seen in
In order to ensure a stable change of the flow areas of the first cut-off portion 201 and the second cut-off portion 301, the shell 100 is provided with a guide structure 50 for guiding the movement of the moving part, enabling the moving part to move stably, thereby changing the combustion power stably. To be specific, the guide structure 50 can guide one of the air cut-off plug 20 and the throat 10. In this embodiment, the guide structure 50 is provided on the gas mixing tube 30. The guide structure 50 comprises a guide rod provided on the gas mixing tube 30. The guide rod and the gas mixing tube 30 are coaxially provided. The upper end of the air cut-off plug 20 is disposed to sleeve the guide rod and slidable relative to the guide rod. When the air cut-off plug 20 performs a linear movement (e.g., the up-down movement shown in
In this embodiment, the shell 100 is provided therein with a guide mechanism 60 defining a moving path of the pivot shaft 43. When moving in the moving path, the pivot shaft 43 causes the throat 10 to move linearly. As shown in
In this embodiment, the first cut-off portion 201 is the part of the whole fuel gas channel 200 which has the minimum flow area. By changing the size of the flow area of the first cut-off portion 201, the adjustment of the fuel gas supply amount of the fuel gas channel 200 is realized. Correspondingly, the second cut-off portion 301 is the part of the whole air channel 300 which has the minimum flow area. By changing the size of the flow area of the second cut-off portion 301, the adjustment of the air supply amount of the air channel 300 is realized.
To achieve a greater regulation ratio, the ratio of the maximum flow area to the minimum flow area of the first cut-off portion 201 is 10 to 30. For example, the ratio of the maximum flow area to the minimum flow area of the first cut-off portion 201 is around 20. The ratio of the maximum flow area to the minimum flow area of the second cut-off portion 301 is 2 to 6. For example, the ratio of the maximum flow area to the minimum flow area of the second cut-off portion 301 is around 4. The regulation ratio of the gas mixing device provided in
In this embodiment, the air cut-off plug 20 and the throat 10 are designed to have gradually varied radians, and the regulation ratio of the gas mixing device (Venturi tube) is changed through the radians to achieve a relative large regulation ratio is achieved. Referring to
In this embodiment, the first mating surface 12 is disposed on the outer wall of the upper end 11 of the throat 10, and the upper end 11 of the throat 10 extends into the lower end of the gas mixing tube 30. The first cut-off portion 201 is formed between the first mating surface 12 and the inner wall of the lower end of the gas mixing tube 30. The first mating surface 12 can be approximately three cambered surfaces of different radians. The cambered surface in the middle projects outwardly, and a smooth transition exist between the cambered surfaces on two sides and the cambered surface in the middle, so that a smooth regulation of the regulation ratio is realized.
The upper end of the air cut-off plug 20 is provided with a second mating surface 22 which participates in forming the second cut-off portion 301. The second mating surface 22 has cambered surfaces with different radians in a moving direction of the air cut-off plug 20. The air cut-off plug 20 moves so that cambered surfaces with different radians are respectively matched with the inner wall of the throat 10 to change the flow area of the second cut-off portion 301. The second cut-off portion 301 is formed between the second mating surface 22 and the inner wall of the throat 10. Referring to
In other embodiments, the driving motor 500 can directly drive the throat 10 and the air cut-off plug 20 to move linearly. No transmission mechanism is required between the throat 10 and the air cut-off plug 20, and the motions of the two are the same. The throat 10 and the air cut-off plug 20 can both be fixedly connected to the output shaft of the driving motor 500 directly, or can be respectively driven by the output shaft, or the throat 10 and the air cut-off plug 20 can be fixedly connected to each other with one of them being directly driven by the output shaft of the driving motor 500, so that they are driven together.
In addition, in other embodiments, the transmission mechanism is not limited to a linkage mechanism. For example, the transmission mechanism may also be a worm gear and worm rod, a gear and chain, belt transmission and so on.
In a feasible embodiment as shown in
The addendum circle diameter of the first driving gear 510 is smaller than that of the second driving gear 520. The screw pitches of the first drive gear 510 and the second drive gear 520 are different. In this embodiment, the above linkage mechanism is changed to be the gear and rack with different screw pitches in this embodiment to realize a synchronous and coaxial linear motion of air and fuel gas at different distances.
For the air cut-off plug 20, throat 10 and gas mixing tube 30 in this embodiment, reference can be made to the description in the embodiment of
In another specific embodiment, as can be seen from
A baffle plate 111 is provided in the fuel gas channel 200. The baffle plate 111 is provided with a flow hole 112 which penetrates the baffle plate. The flow area (the cross sectional area) between the throat 10′ and the gas mixing tube 30′ is greater than the flow area of the first cut-off portion 201. Preferably, the flow area between the throat 10′ and the gas mixing tube 30′ is greater than the area of the flow hole 112 which is not shielded (the maximum flow area of the first cut-off portion 201). The side wall of the upper shell 101 has a fuel gas side tube 110, the baffle plate 111 is located at the tail end of the fuel gas side tube 110, and fuel gas passes through the flow hole 112 of the baffle plate 111 and enter the inner cavity of the upper shell 101 (the annulus space between the inner wall of the shell 101 and the gas mixing tube 30′). The overall fuel gas side tube 110 is perpendicular to the gas mixing tube 30′, and the flow hole 112 faces towards the side wall of the gas mixing tube 30′.
To be specific, the communication area of the flow hole 112 is namely the flow area of the first cut-off portion 201. The baffle plate 111 may be a porous wall surface structure, the flow hole 112 comprises a plurality of air holes distributed on the baffle plate 111, which can be arranged to be an approximately triangular structure, and the number of the air holes increases gradually from top to bottom. Of course, in other embodiments, the flow hole may be a single triangular hole, so that the flow area of the first cut-off portion 201 can be smoothly changed.
The throat 10′ is fixedly provided with a shielding structure 15 for shielding the flow hole 112. The shielding structure 15 moves to change a shielded area of the flow hole 112, so as to change the flow area of the first cut-off portion 201. The shielding structure 15 changes the number of the shielded air holes to change the communication area of the flow hole 112, and thus the flow area of the first cut-off portion 201 can be changed. The shielding structure 15 is disposed on the outer side wall of the throat 10′ and is provided with fuel gas cut-off cotton 151, and thus has a better sealing effect when being attached to the inner wall surface of the baffle plate 111, so that fuel gas can pass through the part of the flow hole 112 which is not shielded.
The air cut-off plug 20′ is fixedly provided with an air cut-off plate 25. The shell 100 is provided with a variable-diameter portion 1021. The variable-diameter portion 1021 is located on the lower shell 102. In this embodiment, the internal cross sectional area (flow area) of the variable-diameter portion 1021 decreases gradually in the air flow direction. When the inner cavity cross section of the lower shell 102 is circular, the internal diameter of the variable-diameter portion 1021 decreases gradually in the air flow direction. The air cut-off plate 25 and the variable-diameter portion move relative to each other to change the flow area of the second cut-off portion 301.
To be specific, the upper end of the air cut-off plug 20′ does not need to have the structure shown in
In this embodiment, the throat 10′, the air cut-off plate 25 and the air cut-off plug 20′ are assembled into one piece and move coaxially, synchronously and equidistantly with the motor 500 as the (linear) motor 500 extends and contracts.
Based on the same idea, the embodiments of the present disclosure also provide a gas water heating device as described in the following embodiments. Since the principles by which the gas water heating device solves problems and the technical effects which the gas water heating device can achieve are similar to that of the gas mixing device. Reference can be made to the implementation of the gas mixing device described above for the implementation of the gas water heating device. No redundant depiction will be given for the repeated content.
A further embodiment of the present disclosure provides a gas water heating device comprising the gas mixing device according to any one of the above embodiments. The gas mixing device can be communicated upstream of the combustor of the gas water heating device for providing premixed gas to the combustor and providing fuel gas to the combustor. The gas water heating device is preferably a fully premixed gas water heater.
Any numeral values cited in this text include all values of the lower values and the upper values from the lower limit value to the upper limit value, in increments of one unit, provided that there is a separation of at least two units between any lower value and any higher value. For example, if a value illustrating the number or process variable (such as temperature, pressure and time, etc.) of a component is from 1 to 90, preferably from 20-80, and more preferably from 30 to 70, then the purpose is to explain that the Description also explicitly enumerates values such as 15 to 85, 22 to 68, 43 to 51 and 30 to 32. For values which are less than one, one unit is appropriately considered to be 0.0001, 0.001, 0.01 or 0.1. These are only examples intended to be explicitly expressed, and all possible combinations of numerical values between the lowest value and the highest value enumerated are all expressly stated in the Description in similar ways.
Unless otherwise stated, all ranges include the endpoints and all numbers that fall between the endpoints. The use of “about” or “approximately” together with a range applies to both ends of the range. Therefore, “about 20 to 30” is intended to cover “about 20 to about 30”, inclusive of at least the specified endpoints.
All disclosed articles and reference materials, including patent applications and publications, are incorporated herein by reference. The term “substantially formed of . . . ” describing combinations should include the determined elements, components, parts or steps as well as other elements, components, parts or steps that do not affect the basic novel features of the combination in substance. The use of the term “contain” or “include” to describe the combinations of elements, components, parts or steps herein also give rise to the embodiments constituted substantially by these elements, components, parts or steps. The term “may” as used herein is intended to explain that any attribute included by the “may” as described is selectable.
Multiple elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step can be divided into multiple separate elements, components, parts or steps. The disclosed “a” or “an” used for describing elements, components, parts or steps do not exclude other elements, components, parts or steps.
It is to be understood that the above description is intended to be graphically illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teaching should not be determined with reference to the above description, but should, instead, be determined with reference to the appended claims, along with the full scope of the equivalents thereof. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of the subject matter that is disclosed herein is not a disclaimer of this subject matter, nor should it be regarded as the inventors not considering this subject matter to be a part of the disclosed utility model subject matter.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202021208020.5 | Jun 2020 | CN | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4420439 | Hartel | Dec 1983 | A |
| 20040237947 | Strohle | Dec 2004 | A1 |
| 20160069563 | Cazard | Mar 2016 | A1 |
| 20180231243 | Nonoyama | Aug 2018 | A1 |
| Number | Date | Country |
|---|---|---|
| 0614045 | Sep 1994 | EP |
| WO-2013060997 | May 2013 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20210404706 A1 | Dec 2021 | US |
