A water pump with parameter reading function based on PWM communication

Abstract

The present application discloses a water pump with parameter reading function based on PWM communication, including a shielded water pump and a parameter reading device, wherein the shielded water pump and the parameter reading device perform PWM communication, and the shielded water pump is provided with a water pump controller, wherein the water pump controller includes a main control chip, a PWM receiving module, a PWM sending module, a motor control module and a power supply module. The present application provides a water pump with parameter reading function based on PWM communication, defines a modulation protocol based on PWM and a set of software response processes of the water pump to the PWM modulation protocol, which can realize the demodulation of the water pump to PWM communication messages, the parsing of parameter query commands, the verification of parameter commands, the modulation of internal parameters to be sent, and the sending of parameters to be sent, thereby realizing the function of uploading complex parameters such as software and hardware version numbers, speed, power, etc. inside the water pump using PWM communication.

Description

Technical Field

[0001] The present application relates to the technical field of shielded water pumps, and in particular to a water pump with a parameter reading function based on PWM communication. Background Art

[0002] For existing shielded water pumps with PWM communication function, since PWM signals represent different information by different duty cycles, the parameters uploaded by the water pump through PWM are limited. As a result, complex parameters such as software and hardware versions, power, speed, etc. of existing shielded water pumps with PWM communication function cannot be read through PWM communication.

[0003] In addition, the axial force balance of the shielded pump has become a key factor affecting the service life and efficiency of the shielded pump. Practice has shown that many failures of shielded pumps are due to the damage of the graphite bearing caused by excessive axial force and poor balance. Therefore, it is particularly important to study the axial force balance method of the shielded pump to minimize or eliminate the damage of the axial force. Although the dynamic balance of the shaft is achieved by balancing the hydraulic pressure before and after the impeller in the prior art, the shaft is still moving and can only be adjusted after the shaft moves, but the movement trend of the shaft cannot be predicted and regulated. Summary of the invention

[0004] The present application proposes a water pump with parameter reading function based on PWM communication, which has the advantage of being able to upload complex parameters, and is used to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions: a water pump with parameter reading function based on PWM communication, comprising a shielded water pump and a parameter reading device, wherein the shielded water pump and the parameter reading device perform PWM communication, and a water pump controller is arranged in the shielded water pump, wherein the water pump controller comprises a main control chip, a PWM receiving module, a PWM sending module, a motor control module and a power supply module;

[0006] The main control chip is responsible for parsing the command information transmitted by the PWM receiving module, and replying the parameter information to the parameter reading device through the PWM sending module;

[0007] The PWM receiving module is responsible for processing the query information transmitted by the parameter reading device through the PWM waveform and transmitting it to the main control chip;

[0008] The PWM sending module is responsible for sending the parameter information replied by the main control chip to the parameter reading device after conversion;

[0009] The motor control module is responsible for the operation control of the shielding water pump motor;

[0010] The power supply module is responsible for providing stable and reliable power supply to other modules of the system.

[0011] Further, the PWM communication protocol is defined as follows:

[0012] There is a high or low level change to "1", which represents a dominant frame;

[0013] No level change is "0", representing a recessive frame;

[0014] Frame header: three consecutive dominant frame PWM pulses;

[0015] Frame end: a dominant frame PWM pulse followed by five consecutive recessive frame PWM pulses;

[0016] Data frame: A dominant frame PWM pulse is inserted after four consecutive recessive frame PWM pulses. Five consecutive recessive frame PWM pulses are not allowed.

[0017] Furthermore, the software processing logic flow of the water pump controller is as follows:

[0018] S1, the main control chip receives PWM signal data;

[0019] S2, demodulate the PWM signal into a communication message;

[0020] S3, perform CRC check on the communication message, if the check fails, the data is discarded; if the check succeeds, go to step S4;

[0021] S4. respond according to the requirements of the communication message;

[0022] S5, modulating the communication message into a PWM signal;

[0023] S6. Send out the modulated PWM signal in the form of a PWM waveform.

[0024] Furthermore, the shielded water pump is provided with a rotor shaft, the rotor shaft is provided with a control cavity, the control cavity is provided with a control component, there are several control components, a driver is connected between the several control components, and the driver is electrically connected to the water pump controller.

[0025] Furthermore, the regulating component includes a detection baffle and a measured baffle. There are two measured baffles, which are respectively located on both sides of the detection baffle. The two measured baffles are in contact with the surface of the detection baffle. The end of the detection baffle away from the inner wall of the shielded water pump is connected to a short friction plate. A long friction plate is provided on the side of the short friction plate away from the detection baffle. The short friction plate is in contact with the surface of the long friction plate. The driving end of the driver is connected to the middle of the long friction plate.

[0026] Furthermore, the detection baffle and the detected baffle are arranged obliquely, and piezoelectric crystals are arranged on two sides of the detection baffle close to the detected baffle, and the piezoelectric crystals are electrically connected to the water pump controller.

[0027] Furthermore, a support rod is provided inside the rotor shaft, one end of the support rod extends to the outside of the rotor shaft and is connected to the shielded water pump, a bearing is provided on the support rod, the outer wall of the bearing is connected to the friction long plate, and the driver is rotatably connected to one end of the support rod.

[0028] 1. The present application provides a water pump with parameter reading function based on PWM communication, defines a modulation protocol based on PWM and a set of software response processes of the water pump to the PWM modulation protocol, which can realize the demodulation of PWM communication messages, parsing of parameter query commands, verification of parameter commands, modulation of internal parameters to be sent, and sending of parameters to be sent by the water pump, thereby realizing the function of uploading complex parameters such as software and hardware version numbers, speed, power, etc. inside the water pump using PWM communication.

[0029] 2. The present application provides a water pump with a parameter reading function based on PWM communication. The water pump obtains the axial movement trend of the rotor shaft by detecting the mutual squeezing between the baffle and the baffle being measured, and when the external hydraulic pressure on the rotor shaft increases, the maximum static friction between the long friction plate and the short friction plate is increased by increasing the thrust of the driver on the long friction plate, thereby increasing the upper limit of the external hydraulic pressure that drives the axial movement of the rotor shaft, preventing the movement of the rotor shaft, and reducing the axial movement of the rotor shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which constitute a part of the specification, illustrate embodiments disclosed in the present application and, together with the description, serve to explain the principles disclosed in the present application.

[0031] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0032] Figure 1 This is the hardware block diagram of the water pump controller of the present invention;

[0033] Figure 2 This is the communication topology diagram of the water pump of the present invention;

[0034] Figure 3 It is the PWM waveform output topology diagram of the present invention;

[0035] Figure 4 This is a data processing flow chart of the water pump controller of the present invention;

[0036] Figure 5 This is a diagram showing the corresponding relationship between the PWM waveform and data of the present invention;

[0037] Figure 6 This is an example diagram of the PWM carrier data structure of the present invention;

[0038] Figure 7 It is a schematic diagram of the partial structure of the rotor shaft of the present invention;

[0039] Figure 8 It is a schematic diagram of the structure of the control component of the present invention.

[0040] In the figure: 1. shielded water pump; 2. parameter reading device; 100. water pump controller; 1000. main control chip; 1001. PWM receiving module; 1002. PWM sending module; 1003. motor control module; 1004. power module; 3. rotor shaft; 4. regulating cavity; 5. regulating component; 501. detection baffle; 502. measured baffle; 503. piezoelectric crystal; 504. friction short plate; 505. friction long plate; 6. driver; 7. support rod; 8. bearing. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] Embodiment 1

[0043] See also Figure 2 , a water pump with parameter reading function based on PWM communication, including a shielded water pump 1 and a parameter reading device 2, the shielded water pump 1 and the parameter reading device 2 perform PWM communication, see the attached Figure 1 and attached Figure 3 The shielded water pump 1 is provided with a water pump controller 100, and the water pump controller 100 includes a main control chip 1000, a PWM receiving module 1001, a PWM sending module 1002, a motor control module 1003 and a power supply module 1004;

[0044] The main control chip 1000 is responsible for parsing the command information transmitted by the PWM receiving module 1001, and replying the parameter information to the parameter reading device 2 through the PWM sending module 1002;

[0045] The PWM receiving module 1001 is responsible for processing and transmitting the query information transmitted by the parameter reading device 2 through the PWM waveform to the main control chip 1000;

[0046] The PWM sending module 1002 is responsible for converting the parameter information replied by the main control chip 1000 and sending it to the parameter reading device 2;

[0047] The motor control module 1003 is responsible for the operation control of the motor of the shielded water pump 1;

[0048] The power module 1004 is responsible for providing stable and reliable power to other modules of the system.

[0049] The operating voltage range of the PWM communication module used by the PWM receiving module 1001 and the PWM transmitting module 1002 of the present application is 4-24V, and the frequency range is 400-4kHz.

[0050] See attached Figure 5 and attached Figure 6 , the PWM communication protocol is defined as follows:

[0051] There is a high or low level change to "1", which represents a dominant frame;

[0052] No level change is "0", representing a recessive frame;

[0053] Frame header: three consecutive dominant frame PWM pulses;

[0054] Frame end: a dominant frame PWM pulse followed by five consecutive recessive frame PWM pulses;

[0055] Data frame: A dominant frame PWM pulse is inserted after four consecutive recessive frame PWM pulses. Five consecutive recessive frame PWM pulses are not allowed.

[0056] Except for the end of the frame and the idle state, the data frame does not allow five consecutive recessive frames to appear. Therefore, when four consecutive recessive frames appear, an explicit frame pulse needs to be inserted to avoid conflict with the end of the frame and to avoid a large phase shift caused by not receiving an explicit frame for a long time.

[0057] See attached Figure 6 The waveform on the left side of the first auxiliary indicator line represents the frame head, the waveform between the first auxiliary indicator line and the second auxiliary indicator line represents the data frame, and the waveform on the right side of the second auxiliary indicator line represents the frame tail.

[0058] An explicit frame indicates a level change, while an implicit frame indicates no level change. Ordinary PWM protocols can only express different data by using different duty cycles. The duty cycle is limited, such as only 1% to 100%, and theoretically can only express 100 data. For a PWM modulation protocol with implicit and explicit frames, its data frame can use a combination of explicit and implicit frames to express binary data. For example, 0100 0001 represents hexadecimal data 0x41: the corresponding ASCII code is: "A" and any information can be transmitted in theory.

[0059] For example: According to the PWM protocol of this application, if the data to be sent is 0x130765, its corresponding binary is: 0001 0011 0000 0111 0110 0101. The modulated data format is: 111|00010011 00001 01110110 0101|100000, where the leftmost 111 represents the frame header, 00001 represents the dominant frame inserted by the continuous recessive frame, and the leftmost 100000 represents the frame tail, indicating the end of the data.

[0060] See attached Figure 4 , the software processing logic flow of the water pump controller 100 is as follows:

[0061] S1, the main control chip 1000 receives PWM signal data;

[0062] S2, demodulate the PWM signal into a communication message;

[0063] S3, perform CRC check on the communication message, if the check fails, the data is discarded; if the check succeeds, go to step S4;

[0064] S4. Respond according to the requirements of the communication message; such as uploading speed data, power data, software and hardware version numbers, etc.;

[0065] S5, modulating the communication message into a PWM signal;

[0066] S6. Send out the modulated PWM signal in the form of a PWM waveform.

[0067] Therefore, the problem that the existing conventional pulse diagram cannot upload parameters such as hardware version, speed, power, etc. can be solved.

[0068] Embodiment 2

[0069] See attached Figure 7 The shielded water pump 1 is provided with a rotor shaft 3, and a regulating cavity 4 is provided in the rotor shaft 3. The regulating cavity 4 and the rotor shaft 3 are integrally formed. The diameter of the rotor shaft 3 at the regulating cavity 4 is larger than the diameter of the rotor shaft 3 at other positions. A regulating component 5 is provided inside the regulating cavity 4. There are several regulating components 5. See the attached Figure 8 In the present application, four regulating components 5 are provided, and a driver 6 is connected between the plurality of regulating components 5, and the driver 6 is electrically connected to the water pump controller 100. The water pump controller 100 controls the gas or liquid entering the driver 6 to achieve synchronous movement of multiple driving ends of the driver 6, thereby ensuring that the thrusts received by the plurality of regulating components 5 corresponding to the plurality of driving ends of the driver 6 are the same, so that the rotor shaft 3 is subjected to the same force.

[0070] See attached Figure 7The regulating component 5 includes a detection baffle 501 and a detected baffle 502. There are two detected baffles 502, which are respectively located on both sides of the detection baffle 501. The two detected baffles 502 are in surface contact with the detection baffle 501. The end of the detection baffle 501 away from the inner wall of the shielded water pump 1 is connected with a friction short plate 504. The side of the friction short plate 504 away from the detection baffle 501 is provided with a friction long plate 505. The friction short plate 504 is in surface contact with the friction long plate 505. The driving end of the driver 6 is connected to the middle of the friction long plate 505. The two ends of the friction long plate 505 are slidably connected to the inner side walls at both ends of the regulating cavity 4.

[0071] The detection baffle 501 and the detected baffle 502 are arranged obliquely. Piezoelectric crystals 503 are arranged on two sides of the detection baffle 501 close to the detected baffle 502 . The piezoelectric crystals 503 are electrically connected to the water pump controller 100 .

[0072] The resultant force of the external liquid pressure on the rotor shaft 3 and the component force of the detection baffle 501 on the detected baffle 502 in the axial direction of the rotor shaft 3 is the resultant force on the rotor shaft 3, and the detection baffle 501 is connected to the detection baffle 501, and the friction short plate 504 can be stationary relative to the friction long plate 505 or move along the friction long plate 505. When the maximum static friction between the friction short plate 504 and the friction long plate 505 is increased, the force transmission of the detection baffle 501 and the detected baffle 502 can increase the extrusion component force of the detection baffle 501 on the rotor shaft 3 in the axial direction, thereby improving the axial balance force of the rotor shaft 3, so that the rotor shaft 3 is not easy to move. That is to say, when the piezoelectric crystal 503 detects that the axial extrusion force of the detected baffle 502 on the detection baffle 501 increases, it indicates that the force exerted by the external liquid on the rotor shaft 3 increases. However, due to the obstruction of the detection baffle 501, the rotor shaft 3 has a tendency to move but has not yet moved. At this time, the obstruction force on the rotor shaft 3 should be increased to prevent the rotor shaft 3 from moving, that is, by extending the driving end of the driver 6, the maximum static friction between the friction short plate 504 and the friction long plate 505 is increased. Since the detection baffle 501, the friction short plate 504 and the rotor shaft 3 are kept stable without relative movement, the hydraulic upper limit of the external hydraulic drive to move the rotor shaft 3 can be increased, so that the rotor shaft 3 does not move. When the piezoelectric crystal 503 detects that the axial pressure of the detected baffle 502 on it decreases, the gas or liquid in the driver 6 can be appropriately released, thereby avoiding the driver 6 from being in a high-pressure energy consumption state all the time, thereby achieving the purpose of saving resources.

[0073] A support rod 7 is provided inside the rotor shaft 3, one end of the support rod 7 extends to the outside of the rotor shaft 3 and is connected to the shielded water pump 1, a bearing 8 is provided on the support rod 7, the outer wall of the bearing 8 is connected to the friction long plate 505, and the driver 6 is rotatably connected to one end of the support rod 7. In this application, the regulating component 5 is designed inside the rotor shaft 3, and a support rod 7 is provided in the inner cavity of the rotor shaft 3, the support rod 7 extends to the outside of the rotor shaft 3 and is connected to the shielded water pump 1, plays a supporting role for the friction long plate 505 and the driver 6, and the bearing 8 is used to ensure the relative rotation of the friction long plate 505 and the support rod 7.

Claims

1. A water pump with parameter reading function based on PWM communication, characterized in that: The invention comprises a canned water pump (1) and a parameter reading device (2), wherein the canned water pump (1) and the parameter reading device (2) perform PWM communication, wherein a water pump controller (100) is provided in the canned water pump (1), and the water pump controller (100) comprises a main control chip (1000), a PWM receiving module (1001), a PWM sending module (1002), a motor control module (1003) and a power supply module (1004); The main control chip (1000) is responsible for parsing the command information transmitted by the PWM receiving module (1001), and responding to the parameter reading device (2) via the PWM sending module (1002); The PWM receiving module (1001) is responsible for processing and transmitting the query information transmitted by the parameter reading device (2) through the PWM waveform to the main control chip (1000); The PWM sending module (1002) is responsible for converting the parameter information replied by the main control chip (1000) and sending it to the parameter reading device (2); The motor control module (1003) is responsible for controlling the operation of the motor of the shielded water pump (1); The power supply module (1004) is responsible for providing stable and reliable power supply to other modules of the system; The shielded water pump (1) is provided with a rotor shaft (3), the rotor shaft (3) is provided with a control chamber (4), a control component (5) is provided inside the control chamber (4), there are a plurality of control components (5), a driver (6) is connected between the plurality of control components (5), and the driver (6) is electrically connected to a water pump controller (100); The regulating component (5) comprises a detection baffle (501) and a detected baffle (502), wherein the number of the detected baffles (502) is two and they are respectively located on both sides of the detection baffle (501), the two detected baffles (502) are in surface contact with the detection baffle (501), one end of the detection baffle (501) away from the inner wall of the shielded water pump (1) is connected to a friction short plate (504), a side of the friction short plate (504) away from the detection baffle (501) is provided with a friction long plate (505), the friction short plate (504) is in surface contact with the friction long plate (505), and the driving end of the driver (6) is connected to the middle of the friction long plate (505); The detection baffle (501) and the detected baffle (502) are arranged at an angle, and piezoelectric crystals (503) are provided on two side surfaces of the detection baffle (501) close to the detected baffle (502), and the piezoelectric crystals (503) are electrically connected to the water pump controller (100).

2. A water pump with parameter reading function based on PWM communication according to claim 1, characterized in that: The PWM communication protocol is defined as follows: There is a high or low level change to "1", which represents a dominant frame; No level change is "0", representing a recessive frame; Frame header: three consecutive dominant frame PWM pulses; Frame end: a dominant frame PWM pulse followed by five consecutive recessive frame PWM pulses; Data frame: A dominant frame PWM pulse is inserted after four consecutive recessive frame PWM pulses. Five consecutive recessive frame PWM pulses are not allowed.

3. A water pump with parameter reading function based on PWM communication according to claim 1, characterized in that: The software processing logic flow of the water pump controller (100) is as follows: S1, the main control chip (1000) receives PWM signal data; S2, demodulate the PWM signal into a communication message; S3, perform CRC check on the communication message, if the check fails, the data is discarded; if the check succeeds, go to step S4; S4. respond according to the requirements of the communication message; S5, modulating the communication message into a PWM signal; S6. Send out the modulated PWM signal in the form of a PWM waveform.

4. A water pump with parameter reading function based on PWM communication according to claim 1, characterized in that: A support rod (7) is provided inside the rotor shaft (3), one end of the support rod (7) extends to the outside of the rotor shaft (3) and is connected to the shielded water pump (1), a bearing (8) is provided on the support rod (7), an outer wall of the bearing (8) is connected to the friction long plate (505), and the driver (6) is rotatably connected to one end of the support rod (7).

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