阅读说明：本技术 液体加热器及其基于液量估计的智能加热控制方法 (Liquid heater and intelligent heating control method thereof based on liquid volume estimation ) 是由 邓财科 周朗荣 于 2021-08-23 设计创作，主要内容包括：本发明公开一种液体加热器及其基于液量估计的智能加热控制方法。智能加热控制方法包括步骤：确定液体加热的目标温度t0,获取液体的初始温度t1,以预设的第一加热功率P1开始加热；以第一加热功率P1持续加热时长T后,获取所述加热容器内的液体的温升△t,估计液体的液量；根据估计得到的所述液量,通过查找预先建立的液量-温度补偿-功率三者的映射表确定出温度补偿值t2和第二加热功率P2；以目标温度t0减去温度补偿值t2确定温度阈值,以第一加热功率P1将液体持续加热达到温度阈值时,以第二加热功率P2继续加热至目标温度t0,P2＜P1。本发明兼顾了加热速度及避免发生快速加热产生剧烈沸腾从而获得较佳的加热效果。(The invention discloses a liquid heater and an intelligent heating control method thereof based on liquid volume estimation. The intelligent heating control method comprises the following steps: determining a target temperature t0 for heating the liquid, acquiring an initial temperature t1 of the liquid, and starting heating at a preset first heating power P1; after the heating is continued for the heating time T at the first heating power P1, obtaining the temperature rise delta T of the liquid in the heating container, and estimating the liquid amount of the liquid; according to the estimated liquid amount, determining a temperature compensation value t2 and a second heating power P2 by searching a pre-established liquid amount-temperature compensation-power mapping table; the temperature threshold is determined by subtracting the temperature compensation value t2 from the target temperature t0, when the liquid is continuously heated by the first heating power P1 to reach the temperature threshold, the liquid is continuously heated to the target temperature t0 by the second heating power P2, and P2 < P1. The invention gives consideration to the heating speed and avoids the rapid heating to generate violent boiling, thereby obtaining better heating effect.)

1. An intelligent heating control method of a liquid heater based on liquid volume estimation is characterized by comprising the following steps:

s1, determining a target temperature t0 for heating the liquid, acquiring an initial temperature t1 of the liquid, and starting heating at a preset first heating power P1;

s2, after the heating is continued for the heating time T at the first heating power P1, obtaining the temperature rise delta T of the liquid in the heating container, and estimating the liquid volume V of the liquid;

s3, according to the estimated liquid volume V, determining a temperature compensation value t2 and a second heating power P2 by searching a pre-established liquid volume-temperature compensation-power mapping table;

s4, subtracting the temperature compensation value t2 from the target temperature t0 to determine a temperature threshold, continuously heating the liquid to the target temperature t0 with the second heating power P2 after the liquid is continuously heated to the temperature threshold with the first heating power P1, and P2 is less than P1.

2. The liquid heater intelligent heating control method based on liquid volume estimation according to claim 1, wherein the estimation formula for estimating the liquid volume V of the liquid in step S2 is:

the liquid volume V = a first heating power P1 a heating time T a thermal efficiency coefficient a/temperature rise Δ T;

where the symbol "+" indicates multiplication, the symbol "/" indicates division, and the thermal efficiency coefficient a is predetermined by test calibration.

3. The liquid heater intelligent heating control method based on liquid volume estimation as claimed in claim 2, wherein the step of determining the thermal efficiency coefficient a in advance through test calibration comprises:

respectively calculating the heat efficiency coefficient a' of the liquid with the known liquid volume V by using the estimation formula under different temperature rises delta t;

and comprehensively determining the thermal efficiency coefficient a by using the plurality of calculated thermal efficiency coefficients a'.

4. The method for intelligently controlling heating of a liquid heater based on liquid volume estimation according to claim 1, wherein the mapping table comprises a plurality of liquid volume intervals divided according to the maximum volume of liquid heating, and a temperature compensation value t2 and a second heating power P2 corresponding to each liquid volume interval are preset respectively.

5. The intelligent heating control method based on liquid volume estimation of the liquid heater as claimed in claim 1, wherein the corresponding temperature compensation value t2 is larger when the liquid volume V is smaller, and the corresponding second heating power P2 is smaller.

6. The intelligent heating control method of the liquid heater based on liquid volume estimation as claimed in claim 1, wherein the corresponding temperature compensation value t2 is smaller when the liquid volume V is larger, and the corresponding second heating power P2 is larger.

7. A liquid heater comprises a heating container for containing liquid, a temperature detection unit for detecting the heating temperature of the liquid in the heating container, an electric heating unit in contact connection with the heating container, a power regulation unit electrically connected with the electric heating unit, and a control unit electrically connected with the temperature detection unit and the power regulation unit respectively; characterized in that the control unit comprises:

the storage module is used for storing a pre-established liquid amount-temperature compensation-power mapping table, a target temperature t0 for heating the liquid and an initial temperature t1 of the liquid;

the liquid volume estimation module is used for acquiring the temperature rise delta T of the liquid in the heating container after the heating is continued for the time T at the first heating power P1, and estimating the liquid volume V of the liquid;

the heating strategy module is used for determining a temperature compensation value t2 and a second heating power P2 by searching the mapping table according to the estimated liquid volume V, and determining a temperature threshold value by subtracting the temperature compensation value t2 from the target temperature t 0;

and the controller is used for controlling the electric heating unit to continuously heat the liquid to reach the temperature threshold value at the first heating power P1, and controlling the electric heating unit to continuously heat to the target temperature t0 at the second heating power P2, wherein P2 < P1.

8. The liquid heater according to claim 7, wherein the liquid amount estimation module estimates the liquid amount V of the liquid by an estimation formula of:

the liquid volume V = first heating power P1 heating time period T thermal efficiency coefficient a/temperature rise Δ T, where symbol "+" represents multiplication, symbol "/" represents division, and thermal efficiency coefficient a is predetermined by test calibration.

9. The liquid heater of claim 7, wherein the corresponding temperature compensation value t2 is greater for smaller amounts of liquid V, the corresponding second heating power P2 is correspondingly less, the corresponding temperature compensation value t2 is less for larger amounts of liquid V, and the corresponding second heating power P2 is correspondingly greater.

10. The liquid heater of claim 7, wherein the power adjusting unit comprises a thyristor, the thyristor is connected in series with the electric heating unit, a control end of the thyristor is electrically connected with one of the control ports of the controller through a switch driving circuit, and the control port outputs a control signal to adjust on-off time of the thyristor to adjust heating power of the electric heating unit.

Technical Field

The invention belongs to the technical field of heating control, and particularly relates to a liquid heater and an intelligent heating control method based on liquid quantity estimation.

Background

Chinese patent application CN2015103500348 discloses an energy-saving kettle and a heating method thereof, wherein when the real-time temperature in the kettle body is lower than a preset temperature threshold, a heating body is heated with a first power, when the real-time temperature in the kettle body water reaches the temperature threshold, the heating is carried out with a second power based on the water amount in the kettle body, the first power is higher than the second power, and the method for calculating the water amount in the kettle body is obtained by calculating the time required by the controller to heat the water in the kettle body from the initial temperature to the preset temperature threshold. This technical scheme reduces heating power and heats after heating temperature reaches the temperature threshold through control energy-conserving kettle, compares and directly adopts full power heating to the water boiling, because of reduced heating power can reduce the hot water and spray out and improve the safety in utilization from the hu kou when boiling to a certain extent, but, this technical scheme still has following technical defect:

the technical scheme is only simple to reduce the heating power, does not provide objective basis for the reduction of the heating power, and does not consider external parameters such as the ambient temperature, the heat dissipation condition of the water temperature and the like, so that the satisfactory heating effect can not be achieved: when the water in the kettle body is less, the kettle body is heated at a temperature threshold value and then is continuously heated at a fixed second power, the heating speed is high, but the kettle body is easy to boil more severely and even dry-fire when the water is small; when the water in the kettle body is more, the water is heated continuously with the fixed second power after the heating reaches the temperature threshold, and the time required for heating the water to boiling is possibly longer, so that the heating speed is slower.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a liquid heater and an intelligent heating control method based on liquid volume estimation, which can intelligently determine the temperature threshold value for reducing the heating power and the second heating power for continuing heating after the temperature threshold value is reduced by estimating the liquid volume of the heated liquid, and can obtain better heating effect by considering the heating speed and avoiding rapid heating and severe boiling.

The invention discloses an intelligent heating control method of a liquid heater based on liquid volume estimation, which comprises the following steps:

s1, determining a target temperature t0 for heating the liquid, acquiring an initial temperature t1 of the liquid, and starting heating at a preset first heating power P1;

s2, after the heating is continued for the heating time T at the first heating power P1, obtaining the temperature rise delta T of the liquid in the heating container, and estimating the liquid volume V of the liquid;

s3, according to the estimated liquid volume V, determining a temperature compensation value t2 and a second heating power P2 by searching a pre-established liquid volume-temperature compensation-power mapping table;

s4, subtracting the temperature compensation value t2 from the target temperature t0 to determine a temperature threshold, continuously heating the liquid with the first heating power P1 until the temperature threshold is reached, continuously heating the liquid with the second heating power P2 until the target temperature t0 is reached, wherein P2 is less than P1.

In one embodiment, the estimation formula for estimating the liquid volume V of the liquid in step S3 is:

the liquid volume V = a first heating power P1 a heating time T a thermal efficiency coefficient a/temperature rise Δ T;

where the symbol "+" indicates multiplication, the symbol "/" indicates division, and the thermal efficiency coefficient a is predetermined by test calibration.

In one embodiment, the step of predetermining the thermal efficiency coefficient a by test calibration comprises:

respectively calculating the heat efficiency coefficient a' of the liquid with the known liquid volume V by using the estimation formula under different temperature rises delta t;

and comprehensively determining the thermal efficiency coefficient a by using the plurality of calculated thermal efficiency coefficients a'.

In one embodiment, the mapping table includes a plurality of liquid volume intervals divided according to the maximum liquid heating capacity, and the temperature compensation value t2 and the second heating power P2 corresponding to each liquid volume interval are preset respectively.

In one embodiment, the temperature compensation value t2 is greater for smaller liquid quantities V and the corresponding second heating power P2 is correspondingly smaller.

In one embodiment, the temperature compensation value t2 is smaller when the liquid volume V is larger, and the corresponding second heating power P2 is larger.

The invention discloses a liquid heater, which comprises a heating container for containing liquid, a temperature detection unit for detecting the heating temperature of the liquid in the heating container, an electric heating unit in contact connection with the heating container, a power regulation unit electrically connected with the electric heating unit, and a control unit electrically connected with the temperature detection unit and the power regulation unit respectively; the control unit includes:

the storage module is used for storing a pre-established liquid amount-temperature compensation-power mapping table, a target temperature t0 for heating the liquid and an initial temperature t1 of the liquid;

the liquid volume estimation module is used for acquiring the temperature rise delta T of the liquid in the heating container after the heating is continued for the time T at the first heating power P1, and estimating the liquid volume V of the liquid;

the heating strategy module is used for determining a temperature compensation value t2 and a second heating power P2 by searching the mapping table according to the estimated liquid volume V, and determining a temperature threshold value by subtracting the temperature compensation value t2 from the target temperature t 0;

and the controller is used for controlling the electric heating unit to continuously heat the liquid to reach the temperature threshold value at the first heating power P1, and controlling the electric heating unit to continuously heat to the target temperature t0 at the second heating power P2, wherein P2 < P1.

In one embodiment, the liquid amount estimation module estimates the liquid amount V of the liquid by the estimation formula: the liquid volume V = first heating power P1 heating time period T thermal efficiency coefficient a/temperature rise Δ T, where symbol "+" represents multiplication, symbol "/" represents division, and thermal efficiency coefficient a is predetermined by test calibration.

In one embodiment, the temperature compensation value t2 is greater for smaller liquid amounts V, the corresponding second heating power P2 is smaller, the temperature compensation value t2 is smaller for larger liquid amounts V, and the corresponding second heating power P2 is greater.

In one embodiment, the power adjusting unit comprises a thyristor, the thyristor is connected in series with the electric heating unit, a control end of the thyristor is electrically connected with one of control ports of the controller through a switch driving circuit, and the control ports output control signals to adjust the on-off time of the thyristor so as to adjust the heating power of the electric heating unit.

Compared with the prior art, the invention has the following beneficial effects:

according to the invention, the liquid volume V of the liquid in the heating container is estimated, an appropriate temperature compensation value t2 and a second heating power P2 are selected and determined by utilizing the estimated liquid volume V, when the liquid in the heating container is heated to reach a temperature threshold determined by subtracting the temperature compensation value t2 from a target temperature t0, the liquid is continuously heated to the target temperature t0 by utilizing the determined second heating power P2, the heating speed is higher when the liquid volume V is large, the violent boiling phenomenon of liquid heating cannot occur, and the liquid volume V can be boiled mildly without easily overflowing when the liquid volume V is small.

Drawings

FIG. 1 is a schematic diagram of a power control circuit for an electric heating unit in a preferred embodiment.

Fig. 2 is a schematic flow chart of the implementation of a preferred embodiment of the invention.

Fig. 3 is a data structure diagram of a mapping table of liquid amount, temperature compensation and power.

Fig. 4 is a diagram illustrating an embodiment of a mapping table of liquid amount, temperature compensation and power.

Fig. 5 is a schematic block diagram of the control unit.

Detailed Description

To further clarify the technical solutions and effects adopted by the present application to achieve the intended purpose, the following detailed description is given with reference to the accompanying drawings and preferred embodiments according to the present application. In the following description, different "one embodiment" or "an embodiment" refers to not necessarily the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

According to the liquid heater disclosed by the invention, the temperature threshold value for reducing the heating power and the second heating power for continuing heating after the temperature threshold value are intelligently determined by estimating the liquid volume of the heated liquid, the heating speed is considered, and the rapid heating is avoided to generate violent boiling, so that a better heating effect can be obtained.

The liquid heater of the invention includes but is not limited to an electric kettle, an electric health preserving kettle or other forms. The liquid heater comprises a heating container for containing liquid, a temperature detection unit (usually a temperature sensor) for detecting the heating temperature of the liquid in the heating container, an electric heating unit in contact connection with the heating container, a power regulation unit electrically connected with the electric heating unit, and a control unit respectively electrically connected with the temperature detection unit and the power regulation unit, wherein the control unit is used for estimating the liquid volume V of the liquid in the heating container, intelligently determining a temperature threshold value and a second heating power P2 which are matched with the liquid volume V, and controlling the electric heating unit to continue heating to a target temperature t0 at the second heating power P2 when the liquid in the heating container is heated to the temperature threshold value.

The electric heating unit can be an electric heating pipe, an electric heating wire, an electric heating film or even an electromagnetic induction element, and is not limited herein.

The control unit controls the power adjusting unit, and the heating power of the electric heating unit is adjusted or changed by using the power adjusting unit, so that the heating power of the electric heating unit is dynamically adjustable, and the electric heating unit does not need to keep fixed heating power to obtain a better liquid heating effect.

In a preferred embodiment as shown in fig. 1: the control unit comprises a controller realized by adopting controllers such as a singlechip, an FPGA and the like; the power regulating unit comprises a controllable silicon TR1, the controllable silicon TR1 is connected with the electric heating unit in series, the control end of the controllable silicon TR1 is electrically connected with one of the control ports of the control unit through a switch driving circuit, and the control port of the controller outputs a control signal to regulate the on-off time of the controllable silicon TR1 so as to achieve the purpose of changing the heating power of the electric heating unit.

Take the example that the control unit comprises a single chip microcomputer. And a control port of the singlechip outputs a PWM control signal. The switch driving circuit comprises a transistor Q1, the base of the transistor Q1 is electrically connected with the control port of the control unit through a resistor R2, the emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is connected with the control end of the controllable silicon TR1 through a resistor R1. The PWM control signal sent by the single chip microcomputer pulls the controllable silicon TR1 to be switched on or switched off correspondingly through the transistor Q1, so that the power-on time of the electric heating unit is changed to adjust the heating power of the electric heating unit.

As shown in fig. 2, specifically, the control unit performs heating control by the following flow:

step S1, determining a target temperature t0 for heating the liquid in the heating container, and controlling the electric heating unit to start heating at a preset first heating power P1 by the control unit acquiring an initial temperature t1 of the liquid in the heating container through the temperature detection unit.

The target temperature t0 is determined by the purpose of the liquid heating. For example, if the purpose of using a liquid heater is to boil water, then the target temperature t0 is 100 ℃; as another example, if the purpose of using a liquid heater is to keep the liquid warm, the target temperature t0 may be 95 ℃ or even 80 ℃.

Generally, in order to improve the heating efficiency, the first heating power P1 is usually the full power or the maximum power P0 of the electric heating unit, so that the liquid in the heating container can be heated most quickly in the shortest time. Of course, the first heating power P1 may be smaller than other preset values of the maximum power P0, i.e., P1 is not greater than P0.

And step S2, after the heating is continued for the heating time period T at the first heating power P1, the control unit obtains the temperature rise Deltat of the liquid in the heating container through the temperature detection unit and estimates the liquid volume V of the liquid in the heating container.

After the heating time period T, the temperature detection unit acquires the real-time temperature of the liquid in the heating container, and the temperature rise delta T can be obtained by subtracting the initial temperature T1 from the real-time temperature.

Specifically, the invention estimates the liquid volume V of the liquid in the heating container according to the energy conservation principle, and the estimation formula is as follows: the first heating power P1, the heating time period T, the thermal efficiency coefficient a = the liquid volume V, the temperature rise Δ T, i.e. the liquid volume V = the first heating power P1, the heating time period T, the thermal efficiency coefficient a/the temperature rise Δ T, wherein the symbol "×" represents a multiplication and the symbol "/" represents a division.

Wherein, the thermal efficiency coefficient a = thermal conductivity coefficient a1 heat dissipation coefficient a 2. The thermal conductivity a1 is the thermal conductivity between the electric heating unit and the liquid in the heating container through the heating container, and is mainly related to the material of the heating container; the heat dissipation coefficient a2 is the heat preservation capability of the heating container, and is mainly related to the material of the heating container. It follows that the thermal efficiency coefficient a is a parameter which is mainly related to the heating vessel.

For a liquid heater, after the structure such as the material and the size of the heating container, the connection relationship between the heating container and the electric heating unit and the like is determined, the thermal efficiency coefficient a can be determined in advance through test calibration. The process of determining the thermal efficiency coefficient a of the liquid heater by the test calibration is as follows:

adding liquid with known liquid volume V into the heating container, respectively calculating to obtain thermal efficiency coefficients a 'by using the estimation formula under different temperature rises delta t, and then comprehensively determining to obtain the thermal efficiency coefficient a by using the calculated multiple thermal efficiency coefficients a'. For example, the thermal efficiency coefficient a may be simply taken as the arithmetic mean of a plurality of thermal efficiency coefficients a'; or removing any two values with the largest difference between the two thermal efficiency coefficients a', and averaging the rest values to obtain the thermal efficiency coefficient a.

Wherein, no matter the liquid volume V is estimated or the thermal efficiency coefficient a of the liquid heater is determined by testing and calibration, the temperature difference delta t is selected to be larger as much as possible, so that the obtained result is relatively more accurate. For example, if the initial water temperature is 40 degrees, the end water temperature may be selected to be 90 degrees, so that the estimated liquid volume V is more accurate with respect to the estimated liquid volume V when the temperature difference Δ t =90-40=50 than when the temperature difference Δ t =10 or 20.

And S3, determining a temperature compensation value t2 and a second heating power P2 by searching a pre-established liquid quantity-temperature compensation-power mapping table according to the estimated liquid quantity V.

As shown in fig. 3, the liquid amount is divided into a plurality of liquid amount intervals according to the maximum capacity L0 of the heating container, and a temperature compensation value t2 and a second heating power P2 corresponding to each liquid amount interval are preset, wherein the principle is that the liquid amount V is inversely proportional to the temperature compensation value t2 and directly proportional to the second heating power P2. I.e. the process is repeated. In the mapping table, the smaller the liquid volume V is, the larger the corresponding temperature compensation value t2 is, and the correspondingly smaller the corresponding second heating power P2 is.

In FIG. 3, 0 < V11 < V12 < V21 < V22 < V31 < V32 … < Vn1 < Vn2 < L0; t21 is more than or equal to t22 is more than or equal to t23 is more than or equal to … is more than or equal to t2n and more than 0, P21 is more than or equal to P22 is more than or equal to P23 is more than or equal to … is more than or equal to P2n is more than P1, and n is a natural number more than 3.

Referring to fig. 4, taking the maximum capacity L0=1.6L of the heating container and the full power or maximum power P0 of the electric heating unit as 1000W as an example, each 0.1L is divided into 16 liquid volume intervals, and each liquid volume interval corresponds to the preset temperature compensation value t2 and the second heating power P2. If the estimated liquid volume V =0.23L, the temperature compensation value t2=5 and the second heating power P2=150W are determined for the liquid volume interval of 0.2 to 0.3. For another example, if the estimated liquid volume V =1.35L, the temperature compensation value t2=2 and the second heating power P2=380W are determined for the liquid volume interval of 1.3 to 1.4.

And step S4, subtracting the temperature compensation value t2 from the target temperature t0 to determine a temperature threshold, and after the liquid in the heating container is continuously heated at the first heating power P1 until the temperature threshold is reached, controlling the electric heating unit to continuously heat at the second heating power P2 until the liquid in the heating container reaches the target temperature t0, and stopping heating by the electric heating unit.

If the water is boiled by a liquid heater, the target temperature t0=100 ℃ is taken as an example:

if the estimated liquid volume V =0.23L, the temperature compensation value t2=5 and the second heating power P2=150W are determined for the liquid volume interval of 0.2 to 0.3. The temperature threshold =100-5=95 ℃ was determined. Therefore, when the real-time temperature of the liquid in the heating container is detected to reach 95 ℃ by the temperature detecting unit, the control unit controls the electric heating unit not to heat up at the power P1 any more, but to reduce the heating power to continue heating up to 100 ℃ at 150W at step S4.

For another example, if the estimated liquid volume V =0.88L, the temperature compensation value t2=3 and the second heating power P2=300W are determined for the liquid volume interval of 0.8 to 0.9. The temperature threshold =100-3=97 ℃ was determined. Therefore, when it is detected by the temperature detecting unit that the real-time temperature of the liquid in the heating container reaches 97 ℃ at step S4, the control unit controls the electric heating unit not to heat up at the power P1 any more, but to decrease the heating power to continue heating up to 100 ℃ at 300W.

Therefore, the reasonable temperature compensation value t2 is selected through the estimated liquid volume V, and the larger temperature compensation value t2 is selected when the liquid volume V is smaller, so that the phenomenon that the liquid is heated to boiling quickly to overflow due to the preheating of the electric heating unit can be avoided; on the contrary, when the liquid volume V is small, the small temperature compensation value t2 is selected, and the determined temperature threshold value is made to be as close to the target temperature t0 as possible, which is beneficial to shortening the heating time and increasing the heating speed.

Further referring to fig. 5, the control unit of the liquid heater specifically includes:

the storage module is used for storing a pre-established liquid amount-temperature compensation-power mapping table, a target temperature t0 for heating the liquid and an initial temperature t1 of the liquid;

the liquid volume estimation module is used for acquiring the temperature rise delta T of the liquid in the heating container after the heating is continued for the time T at the first heating power P1, and estimating the liquid volume V of the liquid;

the heating strategy module is used for determining a temperature compensation value t2 and a second heating power P2 by searching the mapping table according to the estimated liquid volume V, and determining a temperature threshold value by subtracting the temperature compensation value t2 from the target temperature t 0;

and the controller is used for controlling the electric heating unit to continuously heat the liquid to reach the temperature threshold value at the first heating power P1, and controlling the electric heating unit to continuously heat to the target temperature t0 at the second heating power P2, wherein P2 < P1.

The intelligent heating control step shown in fig. 2 is realized by the mutual cooperation of the storage module, the liquid volume estimation module, the heating strategy module and the controller.

In summary, according to the present invention, the liquid volume V of the liquid in the heating container is estimated, and the estimated liquid volume V is used to select and determine the appropriate temperature compensation value t2 and the second heating power P2, when the liquid in the heating container is heated to reach the temperature threshold determined by subtracting the temperature compensation value t2 from the target temperature t0, the liquid is further heated to the target temperature t0 with the determined second heating power P2, so that the heating speed is fast when the liquid volume V is large, the violent boiling phenomenon of liquid heating does not occur, and the liquid volume V is relatively gentle, and the overflow phenomenon is not easy to occur when the liquid volume V is small.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.