Inverter compressor operating frequency adjusting method and device and inverter air conditioner system

[0043] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary, and are only used to explain the present invention, and cannot be construed as limiting the present invention.

[0044] The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are only examples, and are not intended to limit the invention. In addition, the present invention may repeat reference numbers and/or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not in itself indicate the relationship between the various embodiments and/or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the applicability of other processes and/or the use of other materials. In addition, the structure in which the first feature is "on" the second feature described below may include an embodiment in which the first and second features are formed in direct contact, or may include another feature formed between the first and second features In the embodiment, the first and second features may not be in direct contact.

[0045] In the description of the present invention, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, they can be mechanically connected or electrically connected, or two The internal communication of the elements may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meaning of the above terms can be understood according to specific circumstances.

[0046] The following describes the method for adjusting the operating frequency of the inverter compressor, the device for adjusting the operating frequency of the inverter compressor, and the inverter air conditioning system including the device for adjusting the operating frequency of the inverter compressor according to embodiments of the present invention.

[0047] First, the inverter air conditioning system proposed by the embodiment of the present invention will be described with reference to the drawings.

[0048] Such as figure 2 As shown, the inverter air conditioning system of the embodiment of the present invention includes: a signal sending terminal 10, an inverter compressor Mc, a current detection unit 20, and an outdoor unit control unit 21. Among them, the signal sending terminal 10 is used to send control signals. The current detection unit 20 is connected to the inverter compressor Mc, and the current detection unit 20 is used to detect the current current of the inverter compressor Mc. The outdoor unit control unit 21 includes a device 210 for adjusting the operating frequency of the inverter compressor and a signal receiving terminal 211. The signal receiving terminal 211 is used to receive a control signal. The device for adjusting the operating frequency of the inverter compressor 210 and the signal receiving terminal 211 are used for current detection. The unit 20 and the inverter compressor Mc are respectively connected, and the operating frequency adjustment device 210 of the inverter compressor is used to adjust the operating frequency of the inverter compressor Mc according to the control signal and the current current.

[0049] Further, in an embodiment of the present invention, the inverter air conditioning system further includes an indoor unit control unit 30, and the indoor unit control unit 30 is configured to receive control signals and send the control signals to the signal receiving terminal 211.

[0050] further, image 3 It is a structural diagram of an inverter air conditioning system according to a specific embodiment of the present invention. Such as image 3 As shown, the inverter air conditioning system includes an indoor unit 1 and an outdoor unit 2. Among them, the outdoor unit 2 includes an inverter compressor Mc, a current detection unit 20 and an outdoor unit control unit 21. The current detection unit 20 may be a compressor current sensor, and the compressor current sensor may be installed on a circuit board of the outdoor unit control unit 21. The signal issuing terminal 10 may be a remote controller 101, a wire controller 102, etc., and the control signal issued by the signal issuing terminal 10 may be a switch control signal and a mode selection control signal. The adjusting device 210 of the inverter compressor operating frequency in the outdoor unit control unit 21 adjusts the operating frequency of the inverter compressor Mc according to the mode selection control signal and the current current of the inverter compressor Mc. Specifically, such as image 3 As shown, the signal receiving terminal 211 is a signal receiving module, and it only receives the switch control signal and mode selection control signal directly sent from the remote control 101 and the wire controller 102 through the control signal receiving module, or the control signal receiving module receives from The switch control signal and the mode selection control signal sent by the indoor unit 1.

[0051] In addition, such as image 3 As shown, the outdoor unit 2 further includes an external fan Mf, an external expansion valve Ev, an external four-way valve SV, an external unit environmental temperature sensor 22, an external unit system protection sensor 23, and a system parameter collection module 24. Among them, the outdoor unit environmental temperature sensor 22 is used to detect the current ambient temperature of the environment where the outdoor unit 2 is located. The system parameter collection module 24 is connected between each sensor and the outdoor unit control unit 21, and processes the parameters collected by the current detection unit 20, the outdoor unit environmental temperature sensor 22, and the outdoor unit system protection sensor 23 and sends them to the outdoor unit control unit twenty one. Specifically, in an embodiment of the present invention, the outdoor unit control unit 21 further includes a fan output control module 212, an external expansion valve output control module 213, and an external four-way valve output control module 214. Among them, the operating frequency adjustment device 210 of the inverter compressor, the fan output control module 212, the external expansion valve output control module 213, and the external four-way valve output control module 214 are respectively connected with the inverter compressor Mc, the external fan Mf, the external expansion valve Ev, The external four-way valve SV is connected, and according to the collection signal output by the system parameter collection module 24 and the control signal received by the signal receiving terminal 211, the inverter compressor Mc, the external fan Mf, the external expansion valve Ev and the external four-way valve SV Control accordingly.

[0052] Such as image 3 As shown, the indoor unit 1 includes main electrical components such as an indoor unit control unit 30, an indoor fan 14, and an indoor throttle valve 15. The indoor unit control unit 30 may include an internal unit control signal receiving module 11, an internal unit control processor 12, and a signal transmission module 13. The indoor fan 14, the indoor throttle valve 15 and the internal machine control signal receiving module 11 are respectively connected to the internal machine control processor 12, and the indoor fan 14 and the indoor throttle valve 15 are controlled by the internal machine control processor 12. The signal transmission module 13 is connected to the signal receiving terminal 211, and the indoor unit 1 transmits the power on/off control signal and the mode selection control signal to the control signal receiving module of the signal receiving terminal 211 through the signal transmission module 13 according to a general transmission rule. The switch control signal and the mode selection control signal can be directly sent by the remote controller 101 and the wire controller 102 to the signal receiving terminal 211 in the outdoor unit 2. Alternatively, the indoor unit 1 receives the switch control signal and the mode selection control signal sent from the remote controller 101 and the wire controller 102 through the internal control signal receiving module 11, and then the indoor unit 1 transmits the switch control signal and the mode selection control signal through the signal transmission module 13 The mode selection control signal is forwarded to the control signal receiving module of the signal receiving terminal 211 according to a general transmission rule.

[0053] In an embodiment of the present invention, the inverter air conditioning system can control the start-stop and mode selection of the outdoor unit 2 according to the power-on control signal and the mode selection control signal. Wherein, when it is detected that the inverter air conditioner is in the heating mode, the device 210 for adjusting the operating frequency of the inverter compressor obtains the target operating current I AM0 According to the target operating current I AM0 Adjust the operating frequency of the inverter compressor Mc, and when the continuous operating time of the inverter compressor is greater than or equal to the second preset time, such as U minutes, and the current operating frequency of the inverter compressor is greater than or equal to the first preset time, such as W minutes before At the operating frequency, obtain the maximum operating frequency Hzmax of the inverter compressor Mc within X minutes for the third preset time, and obtain the current correction amount ΔI according to the maximum operating frequency Hzmax, and then correct the target operating current I according to the current correction amount ΔI AM0 To update the target operating current I AM0 , And finally according to the updated target operating current I AM0 Adjust the operating frequency of the inverter compressor Mc to achieve automatic inverter control.

[0054] Specifically, when the inverter air conditioner is first started, the device 210 for adjusting the operating frequency of the inverter compressor may set the target operating current I of the inverter compressor Mc according to the capacity of the outdoor unit 2. AM0 Is the preset current value, for example, for a 3-hp outdoor unit 2, set the target operating current I AM0 Set the target operating current I for 10A and for the 4-hp outdoor unit 2 AM0 For 13A. Further, in an embodiment of the present invention, when the inverter compressor Mc is stopped, the device 210 for adjusting the operating frequency of the inverter compressor can adjust the updated target operating current I AM0 As the target operating current I of the inverter compressor Mc when the outdoor unit 2 is turned on next time AM0. Further, in an embodiment of the present invention, when the inverter compressor Mc is operating, the device 210 for adjusting the operating frequency of the inverter compressor may also obtain the target operating current I according to the mode selection control signal. AM0.

[0055] Therefore, the inverter air conditioner system of the embodiment of the present invention can be based on the capacity of the outdoor unit 2 and the continuous operation time of the inverter compressor Mc, the current operating frequency, the maximum operating frequency Hzmax and other parameters when the inverter air conditioner is in a heating mode without communication. To intelligently and automatically adjust the operating frequency of the inverter compressor Mc, so that the ability of the inverter compressor Mc can be used in time and reach the set temperature quickly.

[0056] In an embodiment of the present invention, the inverter air conditioning system may be a one-to-one system or a one-to-multiple system, and the inverter air-conditioning system may be a single cooling unit or a heating and cooling unit. The indoor unit 1 does not communicate the indoor ambient temperature and other parameters to the outdoor unit 2, and only controls the outdoor unit 2 according to the switch control signal and mode selection control signal sent by the remote control 101, the wire controller 102 or the indoor unit 1. Switch and change working mode. The inverter air conditioning system of the embodiment of the present invention can control the inverter compressor Mc in the heating mode where the indoor unit 1 and the outdoor unit 2 do not communicate, and the outdoor unit control unit 21 of the outdoor unit 2 can independently learn to complete the rapid control of the inverter compressor Mc and other electrical components of the outdoor unit 2, so that the indoor temperature reaches and maintains the set temperature.

[0057] Further, in an embodiment of the present invention, when the outdoor unit control unit 21 receives the power-on/off control signal, it delays for a certain time, such as S seconds, to prevent the customer from starting the outdoor unit 2 due to misoperation. To prevent the outdoor unit control unit 21 from making erroneous judgments. In other words, after the outdoor unit control unit 21 receives the power-on/off control signal, it delays a preset time, such as S seconds, to turn on or off.

[0058] According to the inverter air conditioner system of the embodiment of the present invention, the signal receiving terminal in the outdoor unit control unit receives the signal and sends out the control signal sent by the terminal, and then the inverter compressor operating frequency adjustment device in the outdoor unit control unit does not communicate with the inverter air conditioner In the heating mode, the operating frequency of the inverter compressor is adjusted according to the control signal and the current current detected by the current detection unit. The inverter air conditioner system can automatically adjust the operating frequency of the inverter compressor to reach and maintain the set temperature through independent learning according to the parameters of the inverter compressor independent of the indoor unit, without the need for specific communication between the indoor unit and the outdoor unit to transmit the corresponding The control parameters make the structure of the inverter air conditioning system simpler, greatly reduce the cost, reduce the control parameter transmission process, and improve the operating reliability of the air conditioning system.

[0059] The following describes the method for adjusting the operating frequency of the inverter compressor according to the embodiments of the present invention with reference to the accompanying drawings.

[0060] Such as Figure 4 As shown, the method for adjusting the operating frequency of the inverter compressor in the embodiment of the present invention includes the following steps:

[0061] S1: Detect whether the inverter air conditioner is in heating mode.

[0062] S2: Obtain the target operating current of the inverter compressor when the inverter air conditioner is in the heating mode.

[0063] When the inverter air conditioner is first started, the target operating current of the inverter compressor can be set to the preset current value according to the capacity of the outdoor unit. For example, for a 3-hp outdoor unit, set the target operating current to 10A and for a 4-hp outdoor unit, Set the target operating current to 13A. Further, in an embodiment of the present invention, when the inverter compressor is running, the target operating current can also be obtained according to the mode selection control signal.

[0064] S3: Adjust the operating frequency of the inverter compressor according to the target operating current.

[0065] After adjusting the operating frequency of the inverter compressor, proceed to step S4.

[0066] S4: Obtain the continuous running time, the current running frequency, and the running frequency before the first preset time of the inverter compressor.

[0067] S5: Determine whether the continuous running time is greater than or equal to the second preset time and the current operating frequency is greater than or equal to the operating frequency before the first preset time.

[0068] S6: When the continuous operating time is greater than or equal to the second preset time and the current operating frequency is greater than or equal to the operating frequency before the first preset time, obtain the maximum operating frequency of the inverter compressor within the third preset time.

[0069] In step S6, after obtaining the maximum operating frequency of the inverter compressor within the third preset time, proceed to step S7. In addition, in another embodiment of the present invention, when the continuous operating time is greater than or equal to the second preset time and the current operating frequency is less than or equal to the operating frequency before the first preset time, return to step S1.

[0070] S7: Obtain a current correction amount according to the maximum operating frequency, and correct the target operating current according to the current correction amount to update the target operating current.

[0071] In an embodiment of the present invention, the current correction amount may be:

[0072] ΔI=A×Hzmax 2 +B×Hzmax+C

[0073] Among them, Hzmax is the maximum operating frequency, A, B, and C are preset constants, and the current correction amount ΔI is a positive number greater than or equal to zero.

[0074] Further, in an embodiment of the present invention, the target operating current can be updated according to the following formula:

[0075] I AM0 = I AM0 +ΔI

[0076] Where I AM0 Is the target operating current. Since the current correction amount is a positive number greater than or equal to zero, the updated target operating current is greater than the target operating current before the update. It should be noted that the continuous operating time is greater than or equal to the second preset time and the current operating frequency is greater than or equal to the operating frequency before the first preset time, indicating that the target operating current of the inverter compressor is too small and the inverter compressor cannot reach the setting Therefore, the target operating current of the inverter compressor needs to be increased.

[0077] Further, in an embodiment of the present invention, when the inverter compressor is stopped, the updated target operating current may be used as the target operating current of the inverter compressor when the outdoor unit is turned on next time.

[0078] Further, in an embodiment of the present invention, after correcting the target operating current according to the current correction amount to update the target operating current, that is, after step S7, the following steps may be further included:

[0079] S8, reset the continuous running time to zero.

[0080] It should be noted that in an embodiment of the present invention, steps S1 to S7, or steps S1 to S8 can be repeated cyclically. Therefore, in step S8, resetting the continuous running time to zero can ensure that the next work cycle The continuous running time obtained in the above starts from zero, thereby ensuring the reliability of the method for adjusting the operating frequency of the inverter compressor in the embodiment of the present invention.

[0081] In summary, the method for adjusting the operating frequency of the inverter compressor according to the embodiment of the present invention can be based on the capacity of the outdoor unit and the continuous operating time, current operating frequency, and maximum operating time of the inverter compressor when the inverter air conditioner is in a heating mode without communication. Frequency and other parameters are used to intelligently and automatically adjust the operating frequency of the inverter compressor, so that the ability of the inverter compressor can be used in time and reach the set temperature quickly.

[0082] According to the method for adjusting the operating frequency of the inverter compressor according to the embodiment of the present invention, when it is detected that the inverter air conditioner is in the heating mode, the operating frequency of the inverter compressor is adjusted according to the acquired target operating current of the inverter compressor, and when the inverter compressor is judged When the continuous running time of is greater than or equal to the second preset time and the current operating frequency of the inverter compressor is greater than or equal to the operating frequency before the first preset time, the current correction value is obtained, and the target operating current is updated according to the current correction value, thereby Realize the automatic adjustment of the operating frequency of the inverter compressor. The method for adjusting the operating frequency of the inverter compressor can automatically adjust the operating frequency of the inverter compressor through independent learning to reach and maintain the set temperature when the indoor unit and the outdoor unit are not communicating, reducing the control parameter transmission process, and is reliable High sex.

[0083] The device 210 for adjusting the operating frequency of the inverter compressor according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0084] Such as Figure 5 As shown, the device 210 for adjusting the operating frequency of the inverter compressor proposed in the embodiment of the present invention includes a heating mode detection module 215, a target operating current acquisition module 216, an operating frequency adjusting module 217, a continuous operating time and operating frequency acquiring module 218, The judgment module 219, the maximum operating frequency acquisition module 220, and the target operating current update module 221. The heating mode detection module 215 is used to detect whether the inverter air conditioner is in a heating mode. The target operating current obtaining module 216 is used to obtain the target operating current I of the inverter compressor Mc when the inverter air conditioner is in the heating mode. AM0. The operating frequency adjustment module 217 is used to adjust according to the target operating current I AM0 Adjust the operating frequency of the inverter compressor Mc. The continuous operating time and operating frequency acquiring module 218 is used to acquire the continuous operating time of the inverter compressor Mc, the current operating frequency, and the operating frequency before the first preset time, such as W minutes. The determining module 219 is configured to determine whether the continuous running time is greater than or equal to a second preset time, such as U minutes, and whether the current operating frequency is greater than or equal to the operating frequency before the first preset time. The maximum operating frequency obtaining module 220 is configured to obtain the third preset time, such as variable frequency compression within X minutes, when the continuous operating time is greater than or equal to the second preset time and the current operating frequency is greater than or equal to the operating frequency before the first preset time The maximum operating frequency of the machine Mc Hzmax. The target operating current update module 221 is used to obtain the current correction amount ΔI according to the maximum operating frequency Hzmax, and calculate the target operating current I according to the current correction amount ΔI. AM0 Make corrections to update target operating current I AM0.

[0085] Specifically, when the inverter air conditioner is first started, the target operating current acquisition module 216 can set the target operating current I of the inverter compressor Mc according to the capacity of the outdoor unit 2. AM0 Is the preset current value, for example, for a 3-hp outdoor unit 2, set the target operating current I AM0 Set the target operating current I for 10A and for the 4-hp outdoor unit 2 AM0 For 13A. Further, in an embodiment of the present invention, when the inverter compressor Mc is running, the target operating current acquisition module 216 can also acquire the target operating current I according to the received mode selection control signal. AM0.

[0086] Further, in an embodiment of the present invention, the current correction amount ΔI may be:

[0087] ΔI=A×Hzmax 2 +B×Hzmax+C

[0088] Among them, Hzmax is the maximum operating frequency, A, B, and C are preset constants, and the current correction amount ΔI is a positive number greater than or equal to zero.

[0089] Further, in an embodiment of the present invention, the target operating current update module 221 can update the target operating current I according to the following formula AM0 :

[0090] I AM0 = I AM0 +ΔI

[0091] Where I AM0 Is the target operating current. Since the current correction ΔI is a positive number greater than or equal to zero, the updated target operating current I AM0 Greater than the target operating current I before update AM0. It should be noted that the continuous operating time is greater than or equal to the first preset time and the current operating frequency is greater than or equal to the preset frequency, indicating the target operating current I of the inverter compressor Mc AM0 If it is too small, the inverter compressor Mc cannot reach the set temperature. Therefore, it is necessary to increase the target operating current I of the inverter compressor Mc AM0.

[0092] Further, in an embodiment of the present invention, when the inverter compressor Mc is stopped, the updated target operating current I AM0 As the target operating current I of the inverter compressor Mc when the outdoor unit 2 is turned on next time AM0.

[0093] Further, in an embodiment of the present invention, the device 210 for adjusting the operating frequency of the inverter compressor may further include a zeroing module 222. The zeroing module 222 is used to update the target operating current I in the target operating current update module 221. AM0 After that, reset the continuous running time to zero. It should be noted that, in an embodiment of the present invention, the operating frequency adjustment device 210 of the inverter compressor can work repeatedly. Therefore, the zeroing module 222 resets the continuous running time to zero to ensure that the operating frequency of the inverter compressor is The continuous running time of the adjusting device 210 in the next working cycle and the continuous running time acquired by the operating frequency acquisition module 218 start from zero, so as to ensure the reliability of the operating frequency adjusting device 210 of the inverter compressor in the embodiment of the present invention. Sex.

[0094] Further, in another embodiment of the present invention, when the determining module 219 determines that the continuous operating time is greater than or equal to the second preset time and the current operating frequency is less than or equal to the operating frequency before the first preset time, the maximum operating frequency The obtaining module 220 does not obtain the maximum operating frequency Hzmax of the inverter compressor Mc within the third preset time. Therefore, the target operating current update module 221 does not update the target operating current I. AM0.

[0095] In summary, the device 210 for adjusting the operating frequency of the inverter compressor according to the embodiment of the present invention can be based on the capacity of the outdoor unit 2 and the continuous operating time and current operating frequency of the inverter compressor Mc when the inverter air conditioner is in a heating mode without communication. 、Maximum operating frequency Hzmax and other parameters to intelligently automatically adjust the operating frequency of the inverter compressor Mc, so that the ability of the inverter compressor Mc can be used in a timely manner and quickly reach the set temperature requirement.

[0096] When the heating mode detection module detects that the inverter air conditioner is in the heating mode of the device for adjusting the operating frequency of the inverter compressor proposed in the embodiment of the present invention, the operating frequency adjustment module adjusts the target operating current of the inverter compressor acquired by the target operating current acquisition module The operating frequency of the inverter compressor, and when the judgment module determines that the continuous operating time of the inverter compressor is greater than or equal to the second preset time and the current operating frequency of the inverter compressor is greater than or equal to the operating frequency before the first preset time, the target The operating current update module obtains the current correction amount according to the maximum operating frequency obtained by the maximum operating frequency acquisition module, and updates the target operating current according to the current correction amount, thereby realizing automatic adjustment of the operating frequency of the inverter compressor. The operating frequency adjustment device of the inverter compressor can automatically adjust the operating frequency of the inverter compressor of the outdoor unit through independent learning when the indoor unit and the outdoor unit are not communicating to achieve and maintain the set temperature, reducing the transmission of control parameters Process, simple structure, low cost and high reliability.

[0097] Any process or method description in the flowchart or described in other ways herein can be understood as a module, segment, or part of code that includes one or more executable instructions for implementing specific logical functions or steps of the process , And the scope of the preferred embodiment of the present invention includes additional implementations, which may not be in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order according to the functions involved. It is understood by those skilled in the art to which the embodiments of the present invention belong.

[0098] The logic and/or steps represented in the flowchart or described in other ways herein, for example, can be considered as a sequenced list of executable instructions for implementing logic functions, and can be embodied in any computer-readable medium, For use by instruction execution systems, devices, or equipment (such as computer-based systems, systems including processors, or other systems that can fetch instructions from instruction execution systems, devices, or equipment and execute instructions), or combine these instruction execution systems, devices Or equipment. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transmit a program for use by an instruction execution system, device, or device or in combination with these instruction execution systems, devices, or devices. More specific examples (non-exhaustive list) of computer readable media include the following: electrical connections (electronic devices) with one or more wiring, portable computer disk cases (magnetic devices), random access memory (RAM), Read only memory (ROM), erasable and editable read only memory (EPROM or flash memory), fiber optic devices, and portable compact disk read only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable media on which the program can be printed, because it can be used, for example, by optically scanning the paper or other media, and then editing, interpreting, or other suitable media if necessary. The program is processed in a manner to obtain the program electronically and then stored in the computer memory.

[0099] It should be understood that each part of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if it is implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of the following technologies known in the art: a logic gate circuit for implementing logic functions on data signals Discrete logic circuits, application-specific integrated circuits with suitable combinational logic gates, programmable gate array (PGA), field programmable gate array (FPGA), etc.

[0100] Those of ordinary skill in the art can understand that all or part of the steps carried in the method of the foregoing embodiments can be implemented by a program instructing relevant hardware to complete. The program can be stored in a computer-readable storage medium. When executed, it includes one of the steps of the method embodiment or a combination thereof.

[0101] In addition, the functional units in the various embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units may be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or software functional modules. If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it may also be stored in a computer readable storage medium.

[0102] The aforementioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

[0103] In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean specific features described in conjunction with the embodiment or example , Structure, materials or features are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above-mentioned terms does not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner.

[0104] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. And variations, the scope of the present invention is defined by the appended claims and their equivalents.