阅读说明：本技术 一种双模块集成式主动配流的电磁直驱伺服泵 (Double-module integrated type active flow distribution electromagnetic direct-drive servo pump ) 是由 谭草 王赓 李波 孙宾宾 陆佳瑜 鲁应涛 于 2021-09-15 设计创作，主要内容包括：本发明提供了一种双模块集成式主动配流的电磁直驱伺服泵,包括：第一阀块、集成于第一阀块底部的三通开关阀、对称安装于第一阀块和三通开关阀两侧的两个电磁直驱伺服泵模块；两个电磁直驱伺服泵模块结构相同,均包括泵单元、第二阀块、阀单元、泵阀连接体和两个动圈式电磁直线作动器,两个动圈式电磁直线作动器垂直安装于泵阀连接体的一端,并分别同轴连接泵阀连接体另一端的泵单元和阀单元,第二阀块内置安装于泵单元和阀单元中间。本发明的双模块集成式主动配流的电磁直驱伺服泵可根据压力传感器信号切换工作模式,低速轻载下使用单模块驱动,高速轻载下使用双模块串联驱动,低速重载下使用双模块协同驱动,提高伺服泵的工作效率和灵活性。(The invention provides a double-module integrated active flow distribution electromagnetic direct-drive servo pump, which comprises: the electromagnetic direct-drive servo pump comprises a first valve block, a three-way switch valve integrated at the bottom of the first valve block, and two electromagnetic direct-drive servo pump modules symmetrically arranged on two sides of the first valve block and the three-way switch valve; the two electromagnetic direct-drive servo pump modules are identical in structure and respectively comprise a pump unit, a second valve block, a valve unit, a pump valve connector and two moving coil type electromagnetic linear actuators, the two moving coil type electromagnetic linear actuators are vertically installed at one end of the pump valve connector and respectively coaxially connected with the pump unit and the valve unit at the other end of the pump valve connector, and the second valve block is internally installed between the pump unit and the valve unit. The double-module integrated active flow distribution electromagnetic direct-drive servo pump can switch the working mode according to the signal of the pressure sensor, is driven by a single module under low-speed light load, is driven by double modules in series under high-speed light load, and is driven by double modules in a coordinated manner under low-speed heavy load, so that the working efficiency and the flexibility of the servo pump are improved.)

1. The utility model provides an electromagnetism of bimodulus integrated form initiative reposition of redundant personnel directly drives servo pump which characterized in that includes: the electromagnetic direct-drive servo pump comprises a first valve block III, a three-way switch valve IX integrated at the bottom of the first valve block III, and an electromagnetic direct-drive servo pump module I and an electromagnetic direct-drive servo pump module II which are symmetrically arranged on two sides of the first valve block III and the three-way switch valve IX; the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II are identical in structure and respectively comprise a pump unit IV, a second valve block V, a valve unit VI, a pump valve connector VIII and two moving-coil electromagnetic linear actuators VII, the two moving-coil electromagnetic linear actuators VII are vertically arranged at one end of the pump valve connector VIII and are respectively and coaxially connected with the pump unit IV and the valve unit VI at the other end of the pump valve connector VIII, the second valve block V is internally arranged between the pump unit IV and the valve unit VI, and the motion displacement difference between the pump unit IV and the valve unit VI is pi/2 or-pi/2;

the moving-coil electromagnetic linear actuator VII comprises an outer yoke (2), a permanent magnet array (4) bonded on the inner surface of the outer yoke (2), a first end cover (1) and a second end cover (7) which are coaxially and fixedly connected to the two ends of the permanent magnet array (4) through an inner yoke (3), an electromagnetic coil group (6) is wound in a groove of a coil framework (5), the coil framework (5) is sleeved on the inner yoke (3), extending teeth of the coil framework (5) are arranged in an inner cavity of a pump valve connector VIII through a groove of the second end cover (7), and a coil framework connecting plate (9) is fixedly connected with the coil framework (5) through threaded holes in the extending teeth of the coil framework (5); the pump unit V piston rod (12) penetrates through the cylinder body (10), the piston rod (12) close to the VIII end of the pump valve connecting body is coaxially and threadedly connected with the coil framework connecting plate (9), the piston rod (12) is coaxially and fixedly connected with the piston (11), a symmetrical oil suction and discharge working cavity (13) and an oil suction and discharge working cavity (14) are formed between the piston (11) and the cylinder body (10), and a first oil suction and discharge port A is formed in the wall of the oil suction and discharge working cavity_PAnd a second oil suction and discharge port B_P(ii) a The valve core rod (16) of the valve unit VI penetrates through the valve body (14), the valve core rod (16) close to the VIII end of the pump valve connecting body is coaxially and threadedly connected with the coil framework connecting plate (9), the valve core (15) is coaxially and fixedly connected onto the valve core rod (16), a valve cavity is formed between the valve core (15) and the valve body (14), and a first valve port A is arranged on the wall of the valve cavity_VAnd a second valve port B_vAnd a third valve port T₁Fourth valve port T₂And a fifth port P; a first oil suction and discharge port A in the pump unit IV_PAnd a second oil suction and discharge port B_PRespectively connected with the first valve port A in the valve unit VI through the second valve block V_VAnd a second valve port B_vCommunicating;

third valve port T of valve unit VI in electromagnetic direct-drive servo pump module I₁Fourth valve port T₂Through the first valve block III and the third valve port T of the valve unit VI in the electromagnetic direct-drive servo pump module II₁Fourth valve port T₂The first valve block III is communicated with the second valve block III to jointly form a first integrated oil port X, and the fifth valve port P of the valve unit VI in the electromagnetic direct-drive servo pump module I is communicated with the fifth valve port P of the valve unit VI in the electromagnetic direct-drive servo pump module II through the first valve block III to jointly form a second integrated oil port Y; the three-way switch valve IX is an active valve and comprises a middle position function, a left position function and a right position function which are controlled by a load signal, wherein the left position function controls a third valve port T of a valve unit VI in the electromagnetic direct-drive servo pump module I₁Fourth valve port T₂And the fifth valve port P is cut off, and the right computer can control the third valve port T of the valve unit VI in the electromagnetic direct-drive servo pump module II₁Fourth valve port T₂And the fifth valve port P is cut off, and the middle position machine can control the communication of all the valve ports in the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II.

2. The double-module integrated active flow distribution electromagnetic direct-drive servo pump as claimed in claim 1, wherein the permanent magnet array (4) is formed by m axially magnetized permanent magnets (4.1) and n radially magnetized permanent magnets (4.2) which are tightly attached to each other, wherein m and n are positive integers, and m = n + 1.

3. The dual-module integrated active flow distribution electromagnetic direct-drive servo pump as claimed in claim 1, wherein the electromagnetic coil group (6) is composed of a forward coil windings (6.1) and b reverse coil windings (6.2), the winding directions of the coils of the adjacent windings are opposite, wherein a and b are positive integers, and a = b or a-b = ± 1.

4. The dual-module integrated active flow distribution electromagnetic direct-drive servo pump as claimed in claims 1, 2 and 3, wherein the number of windings of the electromagnetic coil group (6) and the number of radially magnetized permanent magnets (4.2) satisfy n = a + b.

5. The double-module integrated active flow distribution electromagnetic direct-drive servo pump as claimed in claim 1, wherein a seal ring is arranged between the pump valve connector VIII and the cylinder body (10) and the valve body (14), and a seal ring is arranged between the piston (11) and the inner wall of the cylinder body (10).

6. The double-module integrated active flow distribution electromagnetic direct-drive servo pump as claimed in claim 1, wherein linear bearings are arranged at the piston rod (12) and the valve core rod (16) far away from the VIII end of the pump valve connecting body, and sealing rings are arranged at the outer ends of the bearings, the cylinder body (10) and the valve body (14).

7. The dual-module integrated active flow distribution electromagnetic direct-drive servo pump as claimed in claims 1 to 6, wherein the electromagnetic direct-drive servo pump has three working modes: the driving device comprises a single module driving device, a double-module series driving device and a double-module cooperative driving device.

Technical Field

The invention relates to the technical field of hydraulic pumps, in particular to a double-module integrated active flow distribution electromagnetic direct-drive servo pump.

Background

The electromagnetic direct-drive servo pump cancels a motion conversion mechanism of rotation-straight line in the middle of the traditional swash plate type plunger pump, shortens a power transmission route, has the advantages of small volume, simple structure, high power density and the like, is convenient for high integration and integration design, and can be widely applied to the fields of aerospace hydrostatic actuators, engineering hydraulic machines, walking hydraulic pressure and the like.

With the high dynamic requirement of the pump control hydraulic system, the working flexibility and the working efficiency of the hydraulic system can be improved by switching the working modes according to specific working conditions, so that the development trend of the direct-drive servo pump is realized. Although a general active flow distribution pump can change the flow rate of pump oil by adjusting the reciprocating motion amplitude and the actuating frequency of a suction oil plunger, the problems of uncertain flow distribution, limited regulation capacity on the flow rate and the pressure of a system and the like still exist.

The invention provides a double-module integrated active flow distribution electromagnetic direct-drive servo pump complete machine structure, which aims to effectively improve the power density of an electromagnetic direct-drive servo pump, improve the system robustness and reduce the nonlinear output of unnecessary flow in work, and fully considers the high-frequency bidirectional driving characteristic of a moving coil type electromagnetic linear actuator and improves the integration degree of the electromagnetic direct-drive servo pump. The working mode can be switched according to specific working conditions in working engineering, the single module drive is used under low-speed light load, the double-module series drive is used under high-speed light load, and the double-module cooperative drive is used under low-speed heavy load. The power transmission efficiency of the whole electromechanical liquid integration can be effectively improved, and the working coordination and the application universality of the electromagnetic direct-drive servo pump are ensured.

Disclosure of Invention

The double-module integrated active flow distribution electromagnetic direct-drive servo pump is designed, the pump flow is periodically operated and applied to different working conditions by switching between a single module and a double module, the robustness of the system can be effectively improved, the nonlinear output of unnecessary flow in the operation process is reduced, and the flexibility of the pump is improved.

In order to achieve the purpose, the electromagnetic direct-drive servo pump with the double-module integrated active flow distribution adopts the following technical scheme:

the utility model provides an electromagnetism of bimodulus integrated form initiative reposition of redundant personnel directly drives servo pump which characterized in that includes: the system comprises a first valve block, a three-way switch valve IX integrated at the bottom of the first valve block III, an electromagnetic direct-drive servo pump module I and an electromagnetic direct-drive servo pump module II which are symmetrically arranged at two sides of the first valve block; the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II are identical in structure and respectively comprise a pump unit, a second valve block, a valve unit, a pump valve connector and two moving-coil electromagnetic linear actuators, the two moving-coil electromagnetic linear actuators are vertically arranged at one end of the pump valve connector and are respectively and coaxially connected with the pump unit and the valve unit at the other end of the pump valve connector, the second valve block is internally arranged between the pump unit and the valve unit, and the motion displacement difference between the pump unit and the valve unit is pi/2;

the moving coil type electromagnetic linear actuator comprises an outer yoke, a permanent magnet array bonded on the inner surface of the outer yoke, a first end cover and a second end cover which are coaxially and fixedly connected with the two ends of the permanent magnet array through the inner yoke, an electromagnetic coil group is wound in a groove of a coil framework, the coil framework is sleeved on the inner yoke, protruding teeth of the coil framework are arranged in an inner cavity of a pump valve connector through the groove of the second end cover, and a coil framework connecting plate is fixedly connected with the coil framework through threaded holes in the protruding teeth of the coil framework; the piston rod of the pump unit penetrates through the cylinder body, the piston rod close to the end of the pump valve connector is coaxially and threadedly connected with the coil framework connecting plate, the piston rod is coaxially and fixedly connected with the piston, a symmetrical oil suction and discharge working cavity and an oil suction and discharge working cavity are formed between the piston and the cylinder body, and a first oil suction and discharge port A is arranged on the wall of the oil suction and discharge working cavity_PAnd a second oil suction and discharge port B_P(ii) a The valve core rod of the valve unit penetrates through the valve body, and the valve core rod close to the end of the pump valve connecting body is connected with the coil frameworkThe connecting plate is coaxially connected with a thread, the valve core rod is coaxially and fixedly connected with the valve core, a valve cavity is formed between the valve core and the valve body, and a first valve port A is arranged on the wall of the valve cavity_VAnd a second valve port B_vAnd a third valve port T₁Fourth valve port T₂And a fifth port P; the first oil suction and discharge port A in the pump unit_PAnd a second oil suction and discharge port B_PThrough the second valve block respectively connected with the first valve port A of the valve unit_VAnd a second valve port B_vCommunicating;

third valve port T of valve unit in electromagnetic direct-drive servo pump module I₁Fourth valve port T₂Through the first valve block and the third valve port T of the valve unit in the electromagnetic direct-drive servo pump module II₁Fourth valve port T₂The first valve block is communicated with the second valve block to jointly form a first integrated oil port X, and the fifth valve port P of the valve unit in the electromagnetic direct-drive servo pump module I is communicated with the fifth valve port P of the valve unit in the electromagnetic direct-drive servo pump module II through the first valve block III to jointly form a second integrated oil port Y; the three-way switch valve IX is an active valve and comprises a middle position function, a left position function and a right position function which are controlled by a load signal, wherein the left position function controls a third valve port T of a valve unit in the electromagnetic direct-drive servo pump module I₁Fourth valve port T₂And the third valve port T of the valve unit in the electromagnetic direct-drive servo pump module II can be controlled by the right computer₁Fourth valve port T₂And the fifth valve port P is cut off, and the middle position machine can control the communication of all the valve ports in the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II.

Furthermore, the permanent magnet array is formed by mutually clinging m axial magnetized permanent magnets and n radial magnetized permanent magnets, wherein m and n are positive integers, and m = n + 1.

Further, the electromagnetic coil group is composed of a forward coil windings and b reverse coil windings, and the winding directions of the coils of the adjacent windings are opposite, wherein a and b are positive integers, and a = b or a-b = +/-1.

Furthermore, the number of windings of the electromagnetic coil group and the number of the radial magnetizing permanent magnets meet n = a + b.

Furthermore, a sealing ring is arranged between the pump valve connector and the cylinder body as well as between the pump valve connector and the valve body, and a sealing ring is arranged between the piston and the inner wall of the cylinder body.

Further, linear bearings are arranged at the piston rod and the valve core rod which are far away from the end of the pump valve connecting body, and sealing rings are arranged at the outer end parts of the bearings, the cylinder body and the valve body.

Further, the electromagnetic direct-drive servo pump has three working modes: the driving device comprises a single module driving device, a double-module series driving device and a double-module cooperative driving device.

Compared with the existing active flow distribution servo pump, the invention has the following advantages.

The double-module integrated active flow distribution electromagnetic direct-drive servo pump directly drives a hydraulic pump by adopting a moving-coil electromagnetic linear actuator based on a Halbach permanent magnet array, has no 'rotation-linear' motion conversion device, and is high in power transmission efficiency and rapid in dynamic response.

In the working process of the double-module integrated active flow distribution electromagnetic direct-drive servo pump, the working mode can be switched according to signals of the pressure sensor, the single module is used for driving under low-speed light load, the double modules are used for driving in series under high-speed light load, and the double modules are used for driving in a coordinated mode under low-speed heavy load, so that the working efficiency and the flexibility of the servo pump are improved.

The double-module integrated active flow distribution electromagnetic direct-drive servo pump integrates the active switch valve for switching the working state and the valve block for controlling the reversing of the hydraulic cylinder, and simultaneously integrates the two modules, so that the structural compactness of the servo pump is improved.

The double-module integrated active flow distribution electromagnetic direct-drive servo pump can provide different parameter indexes aiming at different performance requirements and application targets, ensures the design flexibility of the servo pump, and has wider application range.

Drawings

FIG. 1 is a schematic diagram of a principle of a dual-module integrated active flow distribution electromagnetic direct-drive servo pump.

Fig. 2 is a schematic diagram of the displacement of the pump unit and the valve unit mover (positive displacement) when driven by a single module.

Fig. 3 is a flow curve diagram of the integrated oil port X when the single module driving pump unit is displaced in the forward direction.

Fig. 4 is a flow curve diagram of the integrated oil port Y when the single module driving pump unit is displaced in the forward direction.

Fig. 5 is a flow curve diagram of the integrated oil port X when the single module driving pump unit is reversely displaced.

Fig. 6 is a flow curve diagram of the integrated oil port Y when the single module driving pump unit is reversely displaced.

FIG. 7 is a flow curve diagram of the integrated oil port X when the dual-module tandem drive pump unit is displaced in the forward direction.

FIG. 8 is a flow curve diagram of the integrated oil port Y when the dual-module tandem drive pump unit is displaced in the forward direction.

Fig. 9 is a flow curve diagram of the integrated oil port X when the dual-module cooperative driving pump unit is positively displaced.

Fig. 10 is a flow curve diagram of the integrated oil port Y when the dual-module cooperative driving pump unit is positively displaced.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, the electromagnetic direct-drive servo pump with two modules integrated and active flow distribution includes: the electromagnetic direct-drive servo pump comprises a first valve block III, a three-way switch valve IX integrated at the bottom of the first valve block III, and an electromagnetic direct-drive servo pump module I and an electromagnetic direct-drive servo pump module II which are symmetrically arranged on two sides of the first valve block III and the three-way switch valve IX; the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II are identical in structure and respectively comprise a pump unit IV, a second valve block V, a valve unit VI, a pump valve connector VIII and two moving-coil electromagnetic linear actuators VII, the two moving-coil electromagnetic linear actuators VII are vertically arranged at one end of the pump valve connector VIII and are respectively and coaxially connected with the pump unit IV and the valve unit VI at the other end of the pump valve connector VIII, the second valve block V is internally arranged between the pump unit IV and the valve unit VI, and the motion displacement difference between the pump unit IV and the valve unit VI is pi/2;

the moving-coil electromagnetic linear actuator VII comprises an outer yoke (2) and a permanent magnet array (4) bonded on the inner surface of the outer yoke (2), and is coaxially and fixedly connected with the permanent magnet array through an inner yoke (3)(4) The electromagnetic pump valve connecting structure comprises a first end cover (1) and a second end cover (7) at two ends, an electromagnetic coil group (6) is wound in a groove of a coil framework (5), the coil framework (5) is sleeved on an inner yoke (3), extending teeth of the coil framework (5) are arranged in an inner cavity of a pump valve connecting body VIII through the groove of the second end cover (7), and a coil framework connecting plate (9) is fixedly connected with the coil framework (5) through threaded holes in the extending teeth of the coil framework (5); the pump unit V piston rod (12) penetrates through the cylinder body (10), the piston rod (12) close to the VIII end of the pump valve connecting body is coaxially and threadedly connected with the coil framework connecting plate (9), the piston rod (12) is coaxially and fixedly connected with the piston (11), a symmetrical oil suction and discharge working cavity (13) and an oil suction and discharge working cavity (14) are formed between the piston (11) and the cylinder body (10), and a first oil suction and discharge port A is formed in the wall of the oil suction and discharge working cavity_PAnd a second oil suction and discharge port B_P(ii) a The valve core rod (16) of the valve unit VI penetrates through the valve body (14), the valve core rod (16) close to the VIII end of the pump valve connecting body is coaxially and threadedly connected with the coil framework connecting plate (9), the valve core (15) is coaxially and fixedly connected onto the valve core rod (16), a valve cavity is formed between the valve core (15) and the valve body (14), and a first valve port A is arranged on the wall of the valve cavity_VAnd a second valve port B_VAnd a third valve port T₁Fourth valve port T₂And a fifth port P; a first oil suction and discharge port A in the pump unit IV_PAnd a second oil suction and discharge port B_PRespectively connected with the first valve port A in the valve unit VI through the second valve block V_VAnd a second valve port B_VCommunicating;

third valve port T of valve unit VI in electromagnetic direct-drive servo pump module I₁Fourth valve port T₂Through the first valve block III and the third valve port T of the valve unit VI in the electromagnetic direct-drive servo pump module II₁Fourth valve port T₂The first valve block III is communicated with the second valve block III to jointly form a first integrated oil port X, and the fifth valve port P of the valve unit VI in the electromagnetic direct-drive servo pump module I is communicated with the fifth valve port P of the valve unit VI in the electromagnetic direct-drive servo pump module II through the first valve block III to jointly form a second integrated oil port Y; the three-way switch valve IX is an active valve and comprises a middle position function, a left position function and a right position function which are controlled by a load signalWherein, the left machine can control the third valve port T of the valve unit VI in the electromagnetic direct-drive servo pump module I₁Fourth valve port T₂And the fifth valve port P is cut off, and the right computer can control the third valve port T of the valve unit VI in the electromagnetic direct-drive servo pump module II₁Fourth valve port T₂And the fifth valve port P is cut off, and the middle position machine can control the communication of all the valve ports in the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II.

The permanent magnet array (4) is formed by m axial magnetizing permanent magnets (4.1) and n radial magnetizing permanent magnets (4.2) which are mutually attached, wherein m and n are positive integers, and m = n + 1.

The electromagnetic coil group (6) is composed of a forward coil windings (6.1) and b reverse coil windings (6.2), the winding directions of the coils of the adjacent windings are opposite, wherein a and b are positive integers, and a = b or a-b = +/-1.

The number of windings of the electromagnetic coil group (6) and the number of radial magnetizing permanent magnets (4.2) meet n = a + b.

A sealing ring is arranged between the pump valve connector VIII and the cylinder body (10) and the valve body (14), and a sealing ring is arranged between the piston (11) and the inner wall of the cylinder body (10).

Linear bearings are arranged at the piston rod (12) and the valve core rod (16) far away from the VIII end of the pump valve connecting body, and sealing rings are arranged at the outer end parts of the bearings, the cylinder body (10) and the valve body (14).

The electromagnetic direct-drive servo pump has three working modes: the driving device comprises a single module driving device, a double-module series driving device and a double-module cooperative driving device.

The invention also discloses a working method of the double-module integrated active flow distribution electromagnetic direct-drive servo pump, which comprises the following specific processes: the double-module integrated active flow distribution electromagnetic direct-drive servo pump is driven by two integrated modular pumps and can work in a single module or double modules. When the single module works, the first module can work alone, and the second module can work alone, if the output flow of the two modules is different, the corresponding module can be selected to work according to specific working conditions; the specific working modes are divided into three types: the single module drives, the double modules drive in series, the double modules drive in coordination, the switching of the working mode is adjusted through a three-way switch valve IX integrated at the bottom of a first valve block III, when the load pressure changes, the signal of a pressure sensor is converted into a displacement signal, the position of the three-way switch valve IX is adjusted, and the switching of the working mode is realized.

(1) Single-module drive of electromagnetic direct-drive servo pump

The three-way switch valve IX generates displacement according to a signal of a pressure sensor and is in a left-position function or a right-position function, the electromagnetic direct-drive servo pump module I or the electromagnetic direct-drive servo pump module II single module drive, the motion displacement difference between the pump unit IV and the valve unit VI is pi/2, namely, a piston (11) of the pump unit IV is in a middle position, a valve core (15) of the valve unit VI is in a left position, the displacement of a moving-coil electromagnetic linear actuator VII rotor connected with the pump unit IV and the displacement of a moving-coil electromagnetic linear actuator VII rotor connected with the valve unit VI are shown in figure 2, and the piston (11) of the pump unit IV is in a positive displacement at the moment. At the time 0 to T/4, the piston (11) of the pump unit IV is towards the first oil suction and discharge port A_PSide pressure oil, oil from the first suction port A_PFlows out, flows into the first valve port A of the valve unit VI through the second valve block V_VThen the oil flows into the three-way switch valve IX through a fifth valve port P of the second valve block V and is converged into a second integrated oil port Y of the first valve block III, and the oil is discharged out of the pump from the second integrated oil port Y of the pump; meanwhile, a first integrated oil port X of the pump absorbs oil, and the oil flows into a third valve port T of the valve unit VI from a three-way switch valve IX₁And a fourth port T₂Flows into a second oil suction and discharge port B of the pump unit IV through a second valve block V_PAnd oil absorption is finished. By integrating the movement and position relations of the upper pump unit IV and the valve unit VI, the flow curves of the integrated oil ports X and Y of the electromagnetic direct-drive servo pump in the whole period T are shown in figure 3, and figure 4 shows that the flow is positive and represents oil discharge and the flow is negative and represents oil absorption. Meanwhile, if the piston (11) of the pump unit IV is in reverse displacement, the first integrated oil port X of the pump discharges oil, the second integrated oil port Y sucks oil, and the flow curves of the integrated oil ports X and Y of the electromagnetic direct-drive servo pump in the whole period T are shown in fig. 5 and fig. 6. In summary, if the external load is subjected to reverse servo control, only the moving-coil electromagnetic linear actuation connecting the pump unit IV and the valve unit VI needs to be controlledAnd the reversing can be completed by the motion phase difference between the devices VII.

(2) Electromagnetic direct-drive servo pump double-module series drive

The three-way switch valve IX generates displacement according to signals of the pressure sensor and is in a neutral position function, the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II are driven in series by the two modules, at the moment, the displacement of the pump unit IV in the electromagnetic direct-drive servo pump module I and the displacement of the pump unit IV in the electromagnetic direct-drive servo pump module II are synchronous, namely, no displacement difference exists between the two pump units IV, during forward displacement, the description of the single-module drive is integrated, and the flow curves of the integrated oil ports X and Y of the electromagnetic direct-drive servo pump in the whole period T are driven by the two modules in series as shown in figures 7 and 8.

(3) Double-module cooperative driving of electromagnetic direct-drive servo pump

The three-way switch valve IX generates displacement according to signals of the pressure sensor and is in a neutral position function, the electromagnetic direct-drive servo pump module I and the electromagnetic direct-drive servo pump module II are driven in a cooperative mode, at the moment, the displacement of the pump unit IV in the electromagnetic direct-drive servo pump module I and the displacement of the pump unit IV in the electromagnetic direct-drive servo pump module II are asynchronous, namely the motion displacement difference between the two pump units IV is pi/2, during forward displacement, the description of single-module driving and double-module series driving is integrated, and the oil discharge state of the electromagnetic direct-drive servo pump in the whole period T is driven in a cooperative mode by the double modules as shown in figure 9 and figure 10.

The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.