阅读说明：本技术 应用于车辆的电压转换设备和方法 (Voltage conversion apparatus and method applied to vehicle ) 是由 苗盼盼 刘福林 李志杰 田莹 于 2020-12-31 设计创作，主要内容包括：本申请提供一种应用于车辆的电压转换设备和方法。该设备包括：N组转换结构,其中,每一组转换结构包括子相控制板和子相功率板；每一所述子相控制板,用于获取与子相控制板对应的子相功率板的电流,并调整所述电流之后向与子相控制板对应的子相功率板输出脉冲宽度调制PWM信号；每一所述子相功率板,用于根据接收到的PWM信号调整每一所述子相功率板上的开关进行闭合与断开,以使与每一所述子相功率板上的功率电感产生电压。本申请的设备和方法,只需调整转换结构的数量即可匹配不同型号的燃料电池,从而提高了电压转换设备的适配性,降低电压转换设备的开发成本。(The present application provides a voltage conversion apparatus and method applied to a vehicle. The apparatus comprises: n groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control board and a sub-phase power board; each sub-phase control board is used for acquiring the current of the sub-phase power board corresponding to the sub-phase control board and outputting a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current; each sub-phase power board is used for adjusting a switch on each sub-phase power board to be switched on and switched off according to the received PWM signal so as to enable a power inductor on each sub-phase power board to generate voltage. The device and the method can be matched with fuel cells of different models only by adjusting the number of the conversion structures, thereby improving the adaptability of the voltage conversion device and reducing the development cost of the voltage conversion device.)

1. A voltage conversion apparatus applied to a vehicle, characterized by comprising: n groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control plate and a sub-phase power plate, and N is a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel;

each sub-phase control board is used for acquiring the current of the sub-phase power board corresponding to the sub-phase control board and outputting a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current;

each sub-phase power board is used for adjusting a switch on each sub-phase power board to be switched on and switched off according to the received PWM signal so as to enable a power inductor on each sub-phase power board to generate voltage.

2. The voltage conversion apparatus of claim 1, wherein each of the sub-phase control boards is specifically configured to: acquiring the current of a sub-phase power plate corresponding to the sub-phase control plate; and performing signal adjustment according to the current to generate a plurality of paths of PWM signals.

3. The voltage conversion device of claim 1, wherein the power inductor of each of the sub-phase power plates is configured to convert the stored magnetic field energy into electric field energy to generate the voltage when the switch of each of the sub-phase power plates is turned off.

4. The voltage conversion device according to claim 1, wherein each of the sub-phase power boards is further configured to adjust a switch on each of the sub-phase power boards to be closed according to the received PWM signal, so that a power inductor on each of the sub-phase power boards converts the electric energy into magnetic field energy for storage.

5. The voltage conversion apparatus according to any one of claims 1 to 4, characterized in that the voltage conversion apparatus further comprises: a main control panel; each sub-phase control board is connected with the main control board;

and the main control board is used for acquiring the state information of each sub-phase power board through each sub-phase control board and generating prompt information according to the state information.

6. The voltage conversion apparatus according to claim 5, wherein a temperature sensor is provided on each of the sub-phase power boards; the state information is temperature information;

the main control board is used for acquiring the temperature information of each sub-phase power board through each sub-phase control board and generating prompt information when the value represented by the temperature information is larger than a preset value.

7. The voltage conversion device according to any one of claims 1 to 4, wherein the switch is an Insulated Gate Bipolar Transistor (IGBT) switch.

8. A voltage conversion method applied to a vehicle is characterized in that the method is applied to a voltage conversion device which comprises N groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control plate and a sub-phase power plate, and N is a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel; the method comprises the following steps:

each sub-phase control board acquires the current of the sub-phase power board corresponding to the sub-phase control board, and outputs a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current;

and each sub-phase power board adjusts a switch on each sub-phase power board to be switched on and switched off according to the received PWM signal, so that a power inductor on each sub-phase power board generates voltage.

9. The voltage conversion method according to claim 8, wherein each of the sub-phase control boards is specifically configured to obtain a current of a sub-phase power board corresponding to the sub-phase control board; and performing signal adjustment according to the current to generate a plurality of paths of PWM signals.

10. The voltage conversion method according to claim 8, wherein the power inductor of each of the sub-phase power boards is configured to convert the stored magnetic field energy into electric field energy to generate the voltage when the switch of each of the sub-phase power boards is turned off.

11. The voltage conversion method according to claim 8, wherein each of the sub-phase power boards is further configured to adjust a switch on each of the sub-phase power boards to be closed according to the received PWM signal, so that a power inductor on each of the sub-phase power boards converts the electric energy into magnetic field energy for storage.

12. The voltage conversion method according to any one of claims 8 to 11, wherein the voltage conversion apparatus further comprises: a main control panel; each sub-phase control board is connected with the main control board;

and the main control board acquires the state information of each sub-phase power board through each sub-phase control board and generates prompt information according to the state information.

13. The voltage conversion method according to claim 12, wherein a temperature sensor is disposed on each of the sub-phase power boards; the state information is temperature information;

the main control board acquires the temperature information of each sub-phase power board through each sub-phase control board, and generates prompt information when the value represented by the temperature information is larger than a preset value.

14. The voltage conversion method according to any one of claims 8 to 11, wherein the switch is an Insulated Gate Bipolar Transistor (IGBT) switch.

Technical Field

The present application relates to vehicle technology, and more particularly, to a voltage conversion apparatus and method applied to a vehicle.

Background

In a vehicle provided with a fuel cell, in order to satisfy matching between a power cell and the fuel cell in the vehicle, it is necessary to adjust, for example, boost, a voltage output by the fuel cell.

In the prior art, a voltage conversion device may be provided, which is composed of a driving plate and a plurality of sub-phase power plates, wherein the plurality of sub-phase power plates are connected in parallel between the fuel cell and the power cell, and the driving plate is connected with the plurality of sub-phase power plates, so that each sub-phase power plate is adjusted by the driving plate to adjust the voltage output by the fuel cell.

However, in the prior art, due to the large number of types of fuel cells, after a vehicle is replaced with a fuel cell, the existing voltage conversion equipment cannot match the requirement of voltage adjustment of a new fuel cell, so that the whole voltage conversion equipment needs to be replaced, and the cost is increased.

Disclosure of Invention

The application provides a voltage conversion device and a voltage conversion method applied to a vehicle, which are used for solving the problem that the existing voltage conversion device cannot be matched with the requirement of voltage adjustment of a new fuel cell, and the whole voltage conversion device needs to be replaced, so that the cost is increased.

In one aspect, the present application provides a voltage conversion apparatus applied to a vehicle, the voltage conversion apparatus including: n groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control plate and a sub-phase power plate, and N is a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel;

each sub-phase control board is used for acquiring the current of the sub-phase power board corresponding to the sub-phase control board and outputting a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current;

each sub-phase power board is used for adjusting a switch on each sub-phase power board to be switched on and switched off according to the received PWM signal so as to enable a power inductor on each sub-phase power board to generate voltage.

Optionally, each of the sub-phase control panels is specifically configured to: acquiring the current of a sub-phase power plate corresponding to the sub-phase control plate; and performing signal adjustment according to the current to generate a plurality of paths of PWM signals.

Optionally, the power inductor on each sub-phase power board is configured to convert the stored magnetic field energy into an electric field energy to generate a voltage when the switch on each sub-phase power board is turned off.

Optionally, each of the sub-phase power boards is further configured to adjust a switch on each of the sub-phase power boards to be turned on according to the received PWM signal, so that a power inductor on each of the sub-phase power boards converts electric energy into magnetic field energy to store the magnetic field energy.

Optionally, the voltage conversion device further includes: a main control panel; each sub-phase control board is connected with the main control board;

and the main control board is used for acquiring the state information of each sub-phase power board through each sub-phase control board and generating prompt information according to the state information.

Optionally, a temperature sensor is arranged on each sub-phase power board; the state information is temperature information;

the main control board is used for acquiring the temperature information of each sub-phase power board through each sub-phase control board and generating prompt information when the value represented by the temperature information is larger than a preset value.

Optionally, the switch is an insulated gate bipolar transistor IGBT switch.

In a second aspect, the present application provides a voltage conversion method applied to a vehicle, the method being applied to a voltage conversion apparatus including N sets of conversion structures, wherein each set of conversion structures includes a sub-phase control board and a sub-phase power board, N being a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel; the method comprises the following steps:

each sub-phase control board acquires the current of the sub-phase power board corresponding to the sub-phase control board, and outputs a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current;

and each sub-phase power board adjusts a switch on each sub-phase power board to be switched on and switched off according to the received PWM signal, so that a power inductor on each sub-phase power board generates voltage.

Optionally, each of the sub-phase control boards is specifically configured to obtain a current of a sub-phase power board corresponding to the sub-phase control board; and performing signal adjustment according to the current to generate a plurality of paths of PWM signals.

Optionally, the power inductor on each sub-phase power board is configured to convert the stored magnetic field energy into an electric field energy to generate a voltage when the switch on each sub-phase power board is turned off.

Optionally, each of the sub-phase power boards is further configured to adjust a switch on each of the sub-phase power boards to be turned on according to the received PWM signal, so that a power inductor on each of the sub-phase power boards converts electric energy into magnetic field energy to store the magnetic field energy.

Optionally, the voltage conversion device further includes: a main control panel; each sub-phase control board is connected with the main control board;

and the main control board acquires the state information of each sub-phase power board through each sub-phase control board and generates prompt information according to the state information.

Optionally, a temperature sensor is arranged on each sub-phase power board; the state information is temperature information;

the main control board acquires the temperature information of each sub-phase power board through each sub-phase control board, and generates prompt information when the value represented by the temperature information is larger than a preset value.

Optionally, the switch is an insulated gate bipolar transistor IGBT switch.

The application provides a voltage conversion device and a method applied to a vehicle, wherein the voltage conversion device comprises N groups of conversion structures, each group of conversion structures comprises a sub-phase control plate and a sub-phase power plate, and N is a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel; each sub-phase control board acquires the current of the sub-phase power board corresponding to the sub-phase control board, and outputs a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current; and each sub-phase power board adjusts a switch on each sub-phase power board to be switched off according to the received PWM signal, so that a voltage is generated between the sub-phase power board and a power inductor on each sub-phase power board. The equipment and the method provided by the application can better match the fuel cells of different models only by adjusting the number of the conversion equipment without replacing the whole set of voltage conversion equipment, thereby reducing the development cost and shortening the development period.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

FIG. 1 is a control frame diagram of a prior art voltage conversion device;

fig. 2 is a schematic structural diagram of a voltage conversion device applied to a vehicle according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of another voltage conversion device applied to a vehicle according to an embodiment of the present application;

FIG. 4 is a schematic diagram of the control function of the DSP;

FIG. 5 is a flowchart of a voltage conversion method applied to a vehicle according to an embodiment of the present disclosure;

fig. 6 is a flowchart of another voltage conversion method applied to a vehicle according to an embodiment of the present application.

With the above figures, there are shown specific embodiments of the present application, which will be described in more detail below. These drawings and written description are not intended to limit the scope of the inventive concepts in any manner, but rather to illustrate the inventive concepts to those skilled in the art by reference to specific embodiments.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

With the development of battery technology, fuel cells are used in the automotive field, where a fuel cell vehicle is a vehicle powered by electricity generated by an on-board fuel cell device, and in one example, the voltage range of the fuel cell is 400V (volts) to 750V (volts) dc, and the output voltage range of the fuel cell is typically 200V (volts) to 550V dc, and the voltage needs to be boosted by a voltage conversion device in order to match the voltage ranges of the power cell and the fuel cell during charging and discharging. Fig. 1 is a control framework diagram of a voltage converting apparatus in the prior art, and as shown in fig. 1, a control scheme of the prior voltage converting apparatus generally employs a main control board and a driving board to implement control of a power circuit, wherein the main control board is mainly responsible for system application layer management, including communication, configuration management, and data downloading. The driving board outputs a PWM signal to realize the on and off of the Gate drive mainly by collecting the current of the power circuit, thereby realizing the on and off of an Insulated Gate Bipolar Transistor (IGBT for short).

With the gradual increase of the types of fuel cells in the market and the demands of the whole vehicle market, the voltage conversion devices are more and more in variation, after the fuel cells are replaced by the vehicles, the existing voltage conversion equipment cannot match the voltage regulation demands of new fuel cells, so that the whole voltage conversion equipment needs to be replaced, the voltage conversion equipment needs to be developed again, the development cost is never increased, and the development period is prolonged.

The embodiment of the application provides a voltage conversion device and a voltage conversion method applied to a vehicle, and aims to solve the technical problems.

The following describes the technical solutions of the present application and how to solve the above technical problems with specific embodiments. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments. Embodiments of the present application will be described below with reference to the accompanying drawings.

Fig. 2 is a schematic structural diagram of a voltage conversion device applied to a vehicle according to an embodiment of the present application, where as shown in fig. 2, the voltage conversion device includes: n groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control plate and a sub-phase power plate, and N is a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power board is connected in parallel.

Each sub-phase control board is used for acquiring the current of the sub-phase power board corresponding to the sub-phase control board and outputting a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current.

Specifically, each sub-phase control board obtains the current of the sub-phase power board corresponding to the sub-phase control board, obtains a PWM signal after the current is processed by the DSP, and outputs the PWM signal to the sub-phase power board corresponding to the sub-phase control board, where the PWM signal is used to control the opening and closing of a switch on the sub-phase power board, so as to change the current of the sub-phase power board.

And each sub-phase power board is used for adjusting the switch on each sub-phase power board to be switched on and switched off according to the received PWM signal so as to enable the power inductor on each sub-phase power board to generate voltage.

Illustratively, each sub-phase power board realizes the closing and opening of a switch according to the received PWM signal, and the switch is arranged on each sub-phase power board. After the switch is closed, the power inductor on the sub-phase power board is electrified, the electric energy is converted into magnetic field energy to be stored, after the switch is disconnected, the stored magnetic field energy is converted into the electric energy by the power inductor, a certain voltage exists in the power inductor due to the fact that the magnetic field energy is converted into the electric energy, the voltage superposition generated by the input voltage and the power inductor is the output voltage, and therefore the boosting process is completed, and the output voltage is higher than the input voltage.

The voltage conversion device applied to the vehicle provided by the embodiment comprises N groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control plate and a sub-phase power plate, and N is a positive integer greater than or equal to 1; each sub-phase control board is connected with a main controller of the vehicle, and the power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel, and two ends of each sub-phase power plate are respectively connected with the output end of the fuel cell and the input end of the power cell. Each sub-phase control board is used for acquiring the current of the sub-phase power board corresponding to the sub-phase control board and outputting a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current; and each sub-phase power plate is used for adjusting a switch on each sub-phase power plate to be switched on and switched off according to the received PWM signal so as to enable a power inductor on each sub-phase power plate to generate voltage to adjust the output voltage of the output end of the fuel cell. The fuel cells of various models can be adapted by adjusting the number of groups of the conversion structures without redeveloping the voltage conversion equipment, thereby reducing the development cost of the voltage conversion equipment.

Fig. 3 is a schematic structural diagram of another voltage conversion device applied to a vehicle according to an embodiment of the present application, and based on the embodiment shown in fig. 2, each sub-phase control board of the device is specifically configured to: acquiring the current of a sub-phase power plate corresponding to the sub-phase control plate; and performing signal adjustment according to the current to generate a plurality of paths of PWM signals.

Illustratively, each sub-phase control board uses a digital signal processor DSP to perform digital signal processing operations, and fig. 4 is a control function diagram of the DSP, as shown in fig. 4, where "4 x" is "4 ways". The DSP mainly has two functions, namely, the current of the sub-phase power board is controlled, each sub-phase control board obtains the current of the sub-phase power board corresponding to the sub-phase control board, a PWM signal is obtained after the current is processed by the current control module of the DSP, the PWM signal is output to the sub-phase power board corresponding to the sub-phase control board, and the PWM signal is used for controlling the on-off of a switch on the sub-phase power board, so that the current of the sub-phase power board is controlled; the DSP is used for monitoring the working state of the sub-phase power boards, mainly comprises current, temperature and communication time delay, collecting the temperature through temperature sensors on the sub-phase power boards, collecting four paths of current through current sampling circuits in the sub-phase power boards, and sending the data to the main control board through the SPI bus.

In one example, a power inductor on each sub-phase power plate is used to convert the stored magnetic field energy into electric field energy to generate a voltage when a switch on each sub-phase power plate is opened.

Illustratively, each sub-phase power board is provided with a power inductor for energy conversion so as to perform charging and discharging functions. The switch on each sub-phase power board is an Insulated Gate Bipolar Transistor (IGBT) switch. When the IGBT switch is switched off, the magnetic field energy stored by the power inductor is converted into electric field energy, the electric field energy is superposed with the input power supply voltage and then filtered by a diode and a capacitor to obtain smooth direct current voltage, and the smooth direct current voltage is supplied to a load.

In one example, each sub-phase power board is further configured to adjust a switch on each sub-phase power board to close according to the received PWM signal, so that a power inductor on each sub-phase power board converts the electric energy into magnetic field energy for storage. Specifically, when the sub-phase power board controls the IGBT switch to be closed according to the received PWM signal, and when the IGBT switch is closed, the power inductor converts the electric energy into magnetic field energy to be stored.

In one example, the voltage conversion apparatus further includes: a main control panel; each sub-phase control board is connected with the main control board; and the main control board is used for acquiring the state information of each sub-phase power board through each sub-phase control board and generating prompt information according to the state information. Specifically, each sub-phase power board is provided with a temperature sensor; and the main control board is used for acquiring the temperature information of each sub-phase power board through each sub-phase control board and generating prompt information when the value represented by the temperature information is greater than a preset value.

For example, the main control board is connected to each sub-phase control board for acquiring the state information of the sub-phase power board, as shown in fig. 4, each sub-phase control board may acquire the temperature information of the sub-phase power board corresponding to each sub-phase control board, where the temperature information is the state information of the sub-phase power board. And each sub-phase control board sends the acquired temperature information of the sub-phase power board corresponding to the sub-phase control board to the main control board, and if the number represented by the temperature information is greater than a preset value, the main control board generates prompt information to prompt a user that the temperature of a certain current sub-phase power board is too high, so that the sub-phase power board is monitored and protected.

The voltage conversion device applied to the vehicle comprises N groups of conversion structures, wherein each group of conversion structures comprises a sub-phase control board and a sub-phase power board, each sub-phase control board is connected with a main controller of the vehicle, and a power inductor in each group of conversion structures is arranged on the sub-phase power board; each sub-phase power plate is connected in parallel, and two ends of each sub-phase power plate are respectively connected with the output end of the fuel cell and the input end of the power cell; the equipment is also provided with a main control panel, and each sub-phase control panel is connected with the main control panel. The fuel cells of various models can be adapted by adjusting the number of groups of the conversion structures, and the voltage conversion equipment does not need to be developed again, so that the development cost of the voltage conversion equipment is reduced.

Fig. 5 is a flowchart of a voltage conversion method applied to a vehicle according to an embodiment of the present application, where the method is applied to the voltage conversion apparatus according to the above embodiment, and as shown in fig. 5, the method includes:

101. each sub-phase control board acquires the current of the sub-phase power board corresponding to the sub-phase control board, and outputs a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current;

102. and each sub-phase power board adjusts the switch on each sub-phase power board to be switched on and switched off according to the received PWM signal, so that the power inductor on each sub-phase power board generates voltage.

For example, the present embodiment may refer to the above device embodiments, and the principle and the technical effect are similar and will not be described again.

Fig. 6 is a flowchart of another voltage conversion method applied to a vehicle according to an embodiment of the present application, and based on the embodiment shown in fig. 5, as shown in fig. 6, the method includes:

201. each sub-phase control board acquires the current of the sub-phase power board corresponding to the sub-phase control board, and outputs a Pulse Width Modulation (PWM) signal to the sub-phase power board corresponding to the sub-phase control board after adjusting the current.

In one example, each sub-phase control board is specifically used for acquiring the current of the sub-phase power board corresponding to the sub-phase control board; and performing signal adjustment according to the current to generate a plurality of paths of PWM signals.

202. And each sub-phase power board adjusts the switch on each sub-phase power board to be switched on and switched off according to the received PWM signal, so that the power inductor on each sub-phase power board generates voltage.

In one example, a power inductor on each sub-phase power plate is used to convert the stored magnetic field energy into electric field energy to generate a voltage when a switch on each sub-phase power plate is opened.

In one example, each sub-phase power board is further configured to adjust a switch on each sub-phase power board to close according to the received PWM signal, so that a power inductor on each sub-phase power board converts the electric energy into magnetic field energy for storage.

203. The main control board acquires the state information of each sub-phase power board through each sub-phase control board and generates prompt information according to the state information.

In one example, the voltage conversion apparatus further includes: a main control panel; each sub-phase control board is connected with the main control board.

In one example, each sub-phase power board is provided with a temperature sensor; the state information is temperature information; the main control board acquires the temperature information of each sub-phase power board through each sub-phase control board, and generates prompt information when the value represented by the temperature information is larger than a preset value.

In one example, the switches are insulated gate bipolar transistor, IGBT, switches.

The execution sequence of step 203 and steps 201 and 202 is not limited.

For example, the present embodiment may refer to the above device embodiments, and the principle and the technical effect are similar and will not be described again.

It should be noted that, the embodiments of the present application only take the example of voltage conversion between the fuel cell and the power cell, and the voltage conversion device and the inventive concept of the present application should not be limited to the voltage conversion between the fuel cell and the power cell, and can also be applied to any scene requiring voltage regulation. Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

It will be understood that the present application is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.