A combined and coordinated operation system for a high-pressure pump motor and a solenoid valve

Abstract

The present invention discloses a combined and coordinated operation system for a high-pressure pump motor and a solenoid valve, which includes a micro-plunger pump, a motor, a solenoid valve and a controller. A speed reducer is arranged between the micro-plunger pump and the motor, and the micro-plunger pump is connected to the motor through the speed reducer; the solenoid valve is connected to the micro-plunger pump; both the motor and the solenoid valve are electrically connected to the controller, and the solenoid valve is driven and controlled by collecting the electrical signal of the motor through the controller. In this application, the solenoid valve control adopts pulse width modulation technology, and the three oil circuits are independently controlled by each switch, without interfering with each other, and more precise control of the flow rate and pressure is achieved while realizing the functions of oil circuit switching and on-off; the motor selects a DC brushless motor, and the control algorithm of the supporting controller is used to perform stable closed-loop control on the motor speed, and the motor and the solenoid valve are jointly regulated through a set of controllers. While the motor speed changes, the solenoid valve is controlled to independently open and close the channels to achieve the effect of basically constant pressure in the pump.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechatronic integration control, and particularly relates to a combined and coordinated operation system for a high-pressure pump motor and a solenoid valve. Background Art

[0002] A micro-plunger pump is an important hydraulic device, which is divided into an axial micro-plunger pump and a radial micro-plunger pump. Compared with other types of pumps, it is more pressure-resistant, impact-resistant and has higher efficiency. Its working principle is that the plunger reciprocates in the cylinder block, and the enclosed cavity space composed of the plunger, the cylinder block and the flow distribution parts changes, realizing oil suction and oil discharge.

[0003] As an important part of the electro-hydraulic automatic control system, the high-speed response solenoid valve (HSV) is widely used in the automotive and mechanical fields because it is easy to be controlled in real time in a microprocessor environment and has the advantages of fast response speed, simple structure and low power consumption. In the electro-hydraulic automatic control system, due to its compact structure, small size, light weight, fast response, high reliability and good repeatability, it is an ideal interface component applied to the mechatronic integration system; moreover, because it can directly receive the upper digital signal and control the pressure or flow of the lower system through the PWM wave, it provides a technical means for the digital control of the entire electro-hydraulic automatic control system.

[0004] However, the existing technology cannot coordinate and control the operation of the motor, the solenoid valve and the micro-plunger pump at the same time. The load change of the motor cannot be fed back to the solenoid valve, and the operation change signal of the micro-plunger pump is not utilized to control the operation state change of the motor. The operation of the motor, the solenoid valve and the micro-plunger pump is independent and can only be adjusted manually, and it is impossible to achieve adaptive and precise control. Summary of the Invention

[0005] The purpose of the present invention is to provide a technical solution for a combined and coordinated operation system for a high-pressure pump motor and a solenoid valve, so as to solve the technical problems in the existing technology that the motor, the solenoid valve and the micro-plunger pump cannot cooperate automatically and cannot achieve adaptive and precise control; the load change of the motor cannot be fed back to the solenoid valve and the operation change signal of the micro-plunger pump is not utilized to control the operation state change of the motor. To achieve the above purpose, the specific technical solution of the present invention is as follows:

[0006] A combined and coordinated operation system for a high-pressure pump motor and a solenoid valve, comprising a micro-plunger pump, a motor, a solenoid valve and a controller. A reducer is arranged between the micro-plunger pump and the motor, and the micro-plunger pump is connected to the motor through the reducer; the solenoid valve is connected to the micro-plunger pump; both the motor and the solenoid valve are electrically connected to the controller, and the driving control of the solenoid valve is realized by collecting the electrical signal of the motor through the controller.

[0007] Further, the speed reducer is a sun and planet gear. The sun gear is located at the center, and the planet gears are arranged around the sun gear. The motor shaft of the motor is inserted into the sun gear shaft hole of the sun gear, and the eccentric shaft of the micro-plunger pump is inserted into the planet gear tray shaft hole of the planet gear, thereby establishing a power transmission relationship between the motor and the micro-plunger pump.

[0008] Further, the controller includes a PCB board. An MVU, a motor drive module, a solenoid valve drive module, an enable interface, a Hall interface, two power interfaces, a zero-crossing detection module, a current detection module, and a key module are arranged on the PCB board. The motor drive module includes a drive axle, 6 MOS transistors, and a three-phase motor interface. The three wires of the motor are respectively connected to the three-phase motor interface of the motor drive module on the PCB board; the solenoid valve drive module includes an IO interface for controlling the solenoid valve, and the solenoid valve is electrically connected to the IO interface for controlling the solenoid valve.

[0009] Further, an eccentric shaft is arranged in the middle of the micro-plunger pump. There is an eccentric wheel on the eccentric shaft, and a needle roller bearing is sleeved outside the eccentric wheel; the periphery of the eccentric shaft is a plunger assembly, and the plunger assembly abuts against the needle roller bearing. The plunger assembly includes four plungers arranged around the eccentric shaft, including two large plungers and two small plungers, so as to achieve large flow and high pressure output.

[0010] Further, the solenoid valve is a direct-acting electromagnetic reversing valve, including an oil inlet d and multiple oil outlets. The multiple oil outlets are respectively communicated with the oil inlet d, and the oil inlet d is connected to the oil outlet D of the micro-plunger pump.

[0011] Further, the solenoid valve includes a valve body. An electromagnet assembly is arranged on the valve body. There is an oil inlet d and three oil outlets on the valve body. The three oil outlets are respectively an oil outlet a, an oil outlet b, and an oil outlet c. Three electromagnet mounting holes corresponding to the oil outlet a, the oil outlet b, and the oil outlet c are arranged on the upper part of the valve body.

[0012] Further, the electromagnet assembly is installed in the corresponding electromagnet mounting hole. It includes an electromagnet dust cover, an armature, a return spring, an iron core, and a coil winding column; the electromagnet dust cover is fixedly installed on the end face of the valve body; the coil winding column 45 is a hollow cylindrical structure, which is sleeved outside the iron core and is integrally fixed on the electromagnet dust cover through a nut; a coil is wound outside the coil winding column, and a magnetic field is generated after being energized; the return spring is located between the armature and the iron core; the armature realizes the conduction and blockage of the oil outlet a, the oil outlet b, and the oil outlet c under the action of the return spring.

[0013] Compared with the prior art, the present invention has the following advantages: The motor and solenoid valve combined and coordinated operation system of the present application includes the coordinated operation of the solenoid valve and the micro high-pressure micro plunger pump, and the coordinated operation of the motor and the micro high-pressure micro plunger pump. It can maintain the stability of the pressure inside the pump under the condition of adapting to the load and adjusting the motor speed; The solenoid valve control adopts pulse width modulation technology, and the three oil circuits are independently controlled by each switch without interference, and can more precisely control the flow and pressure while realizing the functions of oil circuit switching, on-off; The motor selected is a DC brushless motor, and the control algorithm of the supporting controller performs stable closed-loop control on the motor speed, and jointly regulates the motor and the solenoid valve through a set of controllers. While the motor speed changes, the solenoid valve is controlled to independently open and close the channels to achieve the effect of basically constant pressure inside the pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic structural diagram of the system of the present invention;

[0015] Figure 2 is a schematic structural diagram of the micro plunger pump of the present invention;

[0016] Figure 3 is a schematic structural diagram of the solenoid valve of the present invention;

[0017] Figure 4 is of the present invention Figure 3 is a cross-sectional view taken along A-A in the present invention;

[0018] Figure 5 is of the present invention Figure 3 is a cross-sectional view taken along B-B in the present invention;

[0019] Figure 6 is a schematic structural diagram of the controller of the present invention.

[0020] In the figure: 1 - micro plunger pump, 11 - eccentric shaft, 12 - eccentric wheel, 13 - needle roller bearing, 14 - bearing, 15 - large plunger, 16 - small plunger, 2 - reducer, 21 - sun gear shaft hole, 22 - planetary gear tray shaft hole, 3 - motor, 31 - motor shaft, 4 - solenoid valve, 41 - valve body, 42 - iron core, 43 - return spring, 44 - armature, 45 - coil winding post, 46 - electromagnetic valve dust cover, 5 - controller. EMBODIMENTS

[0021] In order to better understand the purpose, structure and function of the present invention, the following further describes a high-pressure pump motor and solenoid valve combined and coordinated operation system of the present invention with reference to the accompanying drawings.

[0022] As Figure 1As shown in the figure, a combined and coordinated operation system of a high-pressure pump motor and a solenoid valve includes a micro-plunger pump 1, a motor 3, a solenoid valve 4, and a controller 5. A speed reducer 2 is arranged between the micro-plunger pump 1 and the motor 3. The micro-plunger pump 1 and the motor 3 are connected through the speed reducer 2. The motor shaft 31 of the motor 3 is inserted into the sun gear shaft hole 21 of the speed reducer 2, and the eccentric shaft 11 of the micro-plunger pump 1 is inserted into the planetary gear tray shaft hole 22 of the speed reducer 2. Through such connection, the power transmission relationship between the motor 3 and the micro-plunger pump 1 is established. Both the motor 3 and the solenoid valve 4 are electrically connected to the controller 5, and the controller 5 adjusts the operation of the motor 3 and the solenoid valve 4. The controller 5 includes a PCB board. On the PCB board, there are an MVU, a motor drive module, a solenoid valve drive module, enable interfaces (EA, EB, EZ), Hall interfaces (HA, HB, HC), two power interfaces, a zero-crossing detection module, a current detection module, and a key module (including a RUN key, a STOP key, an UP key, a DOWN key, and a DIR key). The motor drive module includes a drive axle, 6 MOS transistors, and three-phase motor interfaces (three interfaces W, V, U). The three wires of the motor 3 are equivalent to the U, V, and W three-phase wires of an AC motor and are respectively connected to the three interfaces W, V, U of the motor drive module on the PCB board. The solenoid valve drive module includes IO interfaces (PB9, PB8, PB5, PB4, PB3) for controlling the solenoid valve. The solenoid valve 4 is electrically connected to the IO interfaces for controlling the solenoid valve of the controller 5.

[0023] As Figure 2 As shown in the figure, the middle of the micro-plunger pump 1 is an eccentric shaft 11. There is an eccentric wheel 12 on the eccentric shaft 11. A needle roller bearing 13 is sleeved on the eccentric wheel 12 and is in contact with the plunger assembly. Both ends of the eccentric shaft 11 are provided with bearings 14 to fix the position of the eccentric shaft 11. The periphery of the eccentric shaft 11 is the plunger assembly. The plunger assembly includes four plungers arranged around the eccentric shaft 11. There is one plunger above, below, left, and right of the eccentric shaft 11. A plunger sleeve is arranged on the plunger. Only the left and right plungers are shown in the figure, but there are also two plungers above and below the eccentric shaft 11. The sizes of the plungers are one large and one small as shown in the figure, including two large plungers 15 and two small plungers 16, which respectively achieve large flow rate and high pressure output. The one-way valve threshold corresponding to the small plunger 16 is higher, and the output pressure is high. Under the working conditions of high load, the system needs to provide a greater output pressure. The small plunger 16 outputs a greater pressure while reducing the flow rate and reducing the operating speed to ensure the stability of the system. Compared with the small plunger 16, the large plunger 15 has a greater working flow rate and a faster response speed under low load or no-load conditions. The cooperation of the two large plungers 15 and the two small plungers 16 achieves the purpose of adapting to the load and reduces the energy consumption.

[0024] It can be understood that the load of the motor 3 comes from the micro-plunger pump 1. Reflected on the electrical signal, these electrical signals are collected by the controller 5, so as to realize the drive control of the motor 3. The plunger assembly of the micro-plunger pump 1 abuts against the eccentric shaft 11 and generates a reciprocating motion through the eccentricity. It rebounds and resets through the return spring on the plunger assembly to pump out the oil pressure.

[0025] As Figures 3 - 5 shown, the solenoid valve 4 is a direct-acting electromagnetic directional valve, including an oil inlet d and multiple oil outlets. In this embodiment, the oil outlets include three oil outlets a, b, and c. The oil inlet d is connected to the oil outlet D of the micro-plunger pump 1 and returns to the oil bag of the micro-plunger pump 1 through the return oil pipeline after being connected to the external actuator for the next cycle (the actuator and the return oil pipeline are not shown in the figure). Different from the pilot-operated solenoid valve, the direct-acting solenoid valve has a simple structure, a fast switching speed, a high action frequency, can better meet the requirements of the response speed of this electro-hydraulic control system, and has a low cost and is not easy to fail. To improve the defect of high energy consumption of the direct-acting solenoid valve, a program control is developed and designed by the controller to reduce the energy consumption.

[0026] Specifically, the solenoid valve 4 includes a valve body 41, and an electromagnet assembly and an energy storage assembly (not shown in the figure) are arranged on the valve body 41. There is an oil inlet d on the front side of the valve body 41, three oil outlets a, b, and c on the left side, three electromagnet mounting holes corresponding to the oil outlets on the upper part, and three energy storage assembly mounting holes corresponding to the oil outlets a, b, and c on the lower part. Among them, the three oil outlets a, b, and c are respectively communicated with the oil inlet d; threaded structures are provided at the orifices of the oil inlet d and the oil outlets for connecting external pipelines. The electromagnet mounting holes include two upper and lower mounting holes; the upper mounting hole is used to mount the electromagnet, and the bottom of the hole should be kept at a certain distance from the oil outlets a, b, and c; the lower mounting hole is used to place the armature 44, which is communicated with the corresponding oil outlet. The diameter of the lower mounting hole is larger than the diameter of the oil outlet and smaller than the diameter of the upper mounting hole to ensure that the armature 44 can completely block the oil outlet. Threaded structures are provided at the orifices of the energy storage assembly mounting holes for mounting the energy storage assembly; the energy storage mounting hole is communicated with the oil outlet and is not completely penetrated with the oil outlet.

[0027] The electromagnet assembly is installed in the corresponding electromagnet mounting hole, and it includes an electromagnet dust cover 46, an armature 44, a return spring 43, an iron core 42, and a coil winding post 45; the electromagnet dust cover 46 is fixedly installed on the end face of the valve body 41; the coil winding post 45 is of a hollow cylindrical structure, which is sleeved outside the iron core 42 and is integrally fixedly installed on the electromagnet dust cover 46 through a nut; a coil is wound outside the coil winding post 45, and a magnetic field is generated after being energized; the return spring 43 is located between the armature 44 and the iron core 42; both the armature 44 and the iron core 42 are rotating bodies with a T-shaped cross section, and the diameter of the larger end of the armature 44 is the same as and correspondingly arranged with the diameter of the larger end of the iron core 42; an external thread for fixing the iron core 42 is provided at the smaller diameter end of the iron core 42, and the smaller diameter end of the armature 44 is arranged in the corresponding oil outlet, capable of blocking the oil outlet, its diameter is larger than the diameter of the oil outlet, and a sealing ring is provided at this end for sealing, and a buffer gasket is provided at its bottom to reduce impact vibration.

[0028] When the solenoid valve 4 is in the normally closed state without power, each armature 44 blocks the fluid oil outlet under the action of the return spring 43. When it is necessary to conduct the fluid passage, the electromagnet coil 46 at this passage is energized, and the electromagnet generates suction, overcoming the elastic force of the return spring 43 to attract the armature 44, and the armature 44 rises, enabling the fluid oil outlet to conduct. When it is not necessary to conduct the fluid passage, the electromagnet coil at this passage is powered off, and the elastic force of the return spring 43 resets the armature to block the oil outlet.

[0029] It can be understood that three pairs of electromagnets cooperate with the armature 44 to respectively control the opening and closing of three oil circuits. The three oil circuits are independently controlled by their respective switches without interference. The oil inlet d of the solenoid valve 4 is connected to the oil outlet D of the micro-plunger pump. The three oil outlets a, b, and c of the solenoid valve 4 return to the oil bag of the micro-plunger pump 1 through the return oil pipeline after being externally connected to the actuator for the next cycle. The solenoid valve 4 and the PCB board need to be externally powered. For example, the PCB board controls the opening and closing of the three channels of the solenoid valve 4 through the high-level signal of the IO port. The IO ports PB3, PB4, and PB5 of the PCB board respectively correspond to the channels of the oil outlets a, b, and c, and PB9 is connected to the negative pole of the solenoid valve 4.

[0030] In this embodiment, the reducer 2 is a sun and planet gear. The sun gear is located at the center, and the planet gears are arranged around the sun gear. The sun gear transmits torque to the planet gears, which are usually mounted on movable brackets. The strength of the planet gears is usually determined by the size of the sun gear. A larger sun gear will allow a higher torque value. The planet gears revolve around the sun gear and mesh with the external gear ring of the sun gear. The motor 3 is connected to the sun and planet gear through the sun gear shaft hole 21, and the micro-plunger pump 1 is connected to the planet gear tray shaft hole 22 of the sun and planet gear through an internal hexagon. This reduces the input speed, increases the torque, and enhances the stability of the transmission mechanism to achieve the purpose of an ideal transmission effect. The sun and planet gear is small in volume and mass and is suitable for matching with the micro-plunger pump structure; it has a high load-carrying capacity, high transmission efficiency; a relatively large transmission ratio, smooth movement, and strong resistance to impact and vibration.

[0031] The motor 3 includes an electric motor and a driver. The driver is composed of integrated circuits and power electronic devices and is responsible for the speed regulation of the motor. It has a series of advantages such as small size, high power density, large speed regulation range, and high reliability. Through Hall elements, it senses the pole position to determine the commutation time, eliminating the disadvantages of brushed motors. The three wires of the motor 3 are equivalent to the U, V, and W phase wires of an AC motor and are respectively connected to the three-phase wires of the motor drive module on the PCB board. If the current of the motor 3 is very large and vibrations occur after connection, then the wiring order of the three wires is sequentially swapped until the motor 3 operates normally. The three Hall wires of the motor 3 are respectively connected to the Hall ports HA, HB, and HC on the PCB board. By detecting the position of the rotor through Hall elements, it plays a role in controlling the speed of the BLDC.

[0032] To sum up, the PCB board is connected to the three-phase wires of the motor through the U, V, and W phase wires, connected to the Hall elements of the motor through the Hall wires HA, HB, and HC, and controls the motor speed through a program; then it is connected to the relay module through the IO port. The relay is connected to the solenoid valve, and through a high-level control signal, it controls the opening and closing of the solenoid valve channel in the way of controlling a high voltage with a low voltage. Through program development, the PCB board controls the coordinated operation of the entire micro-plunger pump system by jointly regulating the solenoid valve 4 and the motor 3. The speed of the motor 3 is controlled through the key module. While the speed of the motor 3 changes, the solenoid valve 4 is controlled to independently open and close the oil passage to achieve the effect of keeping the pressure in the pump basically constant.

[0033] The present invention controls the multi-channel operation of the solenoid valve 4 through the key module on the PCB board to meet the needs of the multi-functional parallel operation of the micro-plunger pump. Multiple external execution tools can be connected simultaneously to complete operations under complex working conditions. The solenoid valve control program uses pulse width modulation technology. By changing the duty cycle, a large starting current is given to the solenoid valve during the starting stage of the solenoid valve to ensure the rapid response of the solenoid valve. After the solenoid valve responds and enters the holding state stage, a smaller suction force is required compared to the previous stage. To reduce circuit power consumption and extend the service life of the hardware, the design reduces the pulse duty cycle of the program circuit to reduce the current in the circuit, but the current still exceeds the adsorption current threshold of the solenoid valve, and the solenoid valve remains conductive while reducing power consumption.

[0034] The present invention completes the joint regulation of the motor 3 and the solenoid valve 4 through the PCB board, controls the constant pressure and constant speed operation of the micro-plunger pump system. On the basis of stable control of the motor 3 speed, the solenoid valve 4 controls the number of channels according to the motor 3 speed to ensure that the pressure in the pump is basically constant, achieving the purpose of constant pressure. The motor 3 is designed with an initial speed. When the key RUN is pressed, the motor 3 starts, and at this time the solenoid valve 4 opens a single channel. As the speed of the motor 3 increases, the pressure in the pump increases. When the speed of the motor 3 is greater than the set value 1, the solenoid valve 4 opens two channels to reduce the pressure and maintain the stability of the pressure in the pump. Similarly, when the speed of the motor 3 is greater than the set value 2, all three channels of the solenoid valve 4 are opened. When the motor 3 decelerates, the program will also independently control the solenoid valve 4 channels to close. Of course, to cope with emergencies, when it is necessary to immediately stop the system, pressing the key STOP can simultaneously close all the solenoid valve 4 channels and the motor 3.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A combined and coordinated operation system for a high-pressure pump motor and a solenoid valve, characterized in that It includes a micro-plunger pump (1), a motor (3), a solenoid valve (4), and a controller (5). A speed reducer (2) is provided between the micro-plunger pump (1) and the motor (3), and the micro-plunger pump (1) and the motor (3) are connected through the speed reducer (2); the solenoid valve (4) is connected to the micro-plunger pump (1); both the motor (3) and the solenoid valve (4) are electrically connected to the controller (5), and the driving control of the solenoid valve (4) is realized by collecting the electrical signal of the motor (3) through the controller (5). The controller (5) includes a PCB board. An MCU, a motor driving module, a solenoid valve driving module, an enable interface, a Hall interface, two power interfaces, a zero-crossing detection module, a current detection module, and a key module are provided on the PCB board. The motor driving module includes a driving bridge, 6 MOS tubes, and a three-phase motor interface. The three wires of the motor (3) are respectively connected to the three-phase motor interface of the motor driving module on the PCB board; the solenoid valve driving module includes an IO interface for controlling the solenoid valve, and the solenoid valve (4) is electrically connected to the IO interface for controlling the solenoid valve. An eccentric shaft (11) is provided in the middle of the micro-plunger pump (1), and an eccentric wheel (12) is provided on the eccentric shaft (11). A needle roller bearing (13) is sleeved outside the eccentric wheel (12); the periphery of the eccentric shaft (11) is a plunger assembly, and the plunger assembly abuts against the needle roller bearing (13). The plunger assembly includes four plungers arranged around the eccentric shaft (11), including two large plungers (15) and two small plungers (16), so as to achieve large flow rate and high pressure output. The solenoid valve (4) is a direct-acting electromagnetic reversing valve, including an oil inlet d and multiple oil outlets. The multiple oil outlets are respectively communicated with the oil inlet d, and the oil inlet d is connected to the oil outlet D of the micro-plunger pump (1); the solenoid valve (4) includes a valve body (41), and an electromagnet assembly is provided on the valve body (41). The valve body (41) is provided with an oil inlet d and three oil outlets. The three oil outlets are respectively an oil outlet a, an oil outlet b, and an oil outlet c. Three electromagnet mounting holes corresponding to the oil outlet a, the oil outlet b, and the oil outlet c are provided on the upper part of the valve body (41). The electromagnet assembly is installed in the corresponding electromagnet mounting hole, and it includes an electromagnet dust cover (46), an armature (44), a return spring (43), an iron core (42), and a coil winding column (45); the electromagnet dust cover (46) is fixedly installed on the end face of the valve body (41); the coil winding column 45 is a hollow cylindrical structure, which is sleeved outside the iron core (42) and is integrally fixed on the electromagnet dust cover (46) through a nut; a coil is wound outside the coil winding column (45), and a magnetic field is generated after being energized; the return spring (43) is located between the armature (44) and the iron core (42); the armature (44) realizes the conduction and blockage of the oil outlet a, the oil outlet b, and the oil outlet c under the action of the return spring (43).

2. The combined and coordinated operation system of a high-pressure pump motor and a solenoid valve according to claim 1, wherein The speed reducer (2) is a sun and planet gear. The sun gear is located at the center, and the planet gears are arranged around the sun gear. The motor shaft (31) of the motor (3) is inserted into the sun gear shaft hole (21) of the sun gear, and the eccentric shaft (11) of the micro plunger pump (1) is inserted into the planet gear tray shaft hole (22) of the planet gear, thereby establishing a power transmission relationship between the motor (3) and the micro plunger pump (1).

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