Electromagnetic grading pressure-adjusting type mine electro-hydraulic control speed regulating system and hydraulic support assembly

Abstract

The electromagnetic grading pressure regulating type mine electro-hydraulic control speed regulating system and the hydraulic support assembly are provided, the speed regulating valve comprises a system liquid inlet end, a system liquid return end, a hydraulic cylinder, a valve assembly and a controller, the valve assembly comprises a first reversing valve, a second reversing valve, a first electromagnetic pilot valve and a second electromagnetic pilot valve, the controller is connected with control ends of the first electromagnetic pilot valve and the second electromagnetic pilot valve, the system liquid inlet end is connected with liquid inlet openings of the first reversing valve, the second reversing valve, the first electromagnetic pilot valve and the second electromagnetic pilot valve, liquid outlet openings of the first electromagnetic pilot valve are connected with control cavities of the first reversing valve and the second reversing valve, liquid outlet openings of the first reversing valve and the second reversing valve are connected with a rodless cavity and a rod cavity, the first reversing valve is a two-stage flow reversing valve, and the first electromagnetic pilot valve is a two-stage flow electromagnetic pilot valve. The present disclosure controls the opening degree of the pilot valve by proportional output or grading output of high-pressure liquid to realize output of different flow.

Description

Technical Field

[0001] This disclosure relates to the technical field of control valves, and more specifically, to an electromagnetic graded pressure regulating type electro-hydraulic speed control system for mining and a hydraulic support assembly. Background Technology

[0002] The electro-hydraulic directional valve is a core component of an electro-hydraulic control system. It is a hydraulically actuated directional valve composed of a solenoid pilot valve and a main valve. High-pressure fluid in the solenoid pilot valve's hydraulic circuit drives the main valve spool, controlling the movement of the actuator. As a key component in the electro-hydraulic control of hydraulic supports, the electro-hydraulic directional valve plays a crucial role in realizing fully mechanized and unmanned mining in coal mines. However, current electro-hydraulic directional valves still have some problems. For example, existing electro-hydraulic directional valves struggle to achieve precise control of the hydraulic support jacks to meet the demands of mechanized and unmanned coal mining; the main issue is the inability to accurately control the flow rate through the electro-hydraulic directional valve. Summary of the Invention

[0003] To address the aforementioned problems in the prior art, this disclosure provides an electromagnetic graded voltage regulating type electro-hydraulic speed control system for mining and a hydraulic support assembly.

[0004] In view of this, one embodiment of the present disclosure provides an electromagnetic graded pressure regulating electro-hydraulic speed control system for mining, including a system inlet end, a system return end, a hydraulic cylinder, a valve assembly, and a controller. The hydraulic cylinder includes a rodless chamber and a rod chamber. The valve assembly includes a first directional valve, a second directional valve, a first electromagnetic pilot valve, and a second electromagnetic pilot valve. The controller is connected to the control terminals of the first electromagnetic pilot valve and the second electromagnetic pilot valve, respectively. The system inlet end is connected to the inlets of the first directional valve, the second directional valve, the first electromagnetic pilot valve, and the second electromagnetic pilot valve, respectively. The outlet of the first electromagnetic pilot valve is connected to the control chamber of the first directional valve and the control chamber of the second directional valve, respectively. The outlets of the first directional valve and the second directional valve are connected to the rodless chamber and the rod chamber, respectively. The first directional valve is a two-stage flow directional valve, and the first electromagnetic pilot valve is a two-stage flow electromagnetic pilot valve.

[0005] In some embodiments, the system return port is connected to the return ports of the first reversing valve, the second reversing valve, the first solenoid pilot valve, and the second solenoid pilot valve.

[0006] In some embodiments, the system inlet is connected to the inlet of the first directional valve and the inlet of the second directional valve via a first inlet pipe. The return ports of the first and second directional valves are connected to the system return end via a first return pipe. The system inlet is connected to the inlet of the first and second electromagnetic pilot valves via a second inlet pipe. The return ports of the first and second electromagnetic pilot valves are connected to the system return end via a second return pipe.

[0007] In some embodiments, the outlet of the first electromagnetic pilot valve is connected to the control chamber of the second directional valve through a first pipeline, and the outlet of the second electromagnetic pilot valve is connected to the control chamber of the second directional valve through a second pipeline.

[0008] In some embodiments, a filter device and a first check valve are provided on the second inlet pipeline. The filter device is located between the system inlet end and the inlet ports of the first electromagnetic pilot valve and the second electromagnetic pilot valve. The first check valve is located between the system inlet end and the filter device.

[0009] In some embodiments, a third check valve is provided on the second return line, and the third check valve is located between the return end of the system and the return ports of the first electromagnetic pilot valve and the second electromagnetic pilot valve.

[0010] In some embodiments, the second directional valve is a two-stage flow directional valve, and the second solenoid pilot valve is a two-stage flow solenoid pilot valve.

[0011] In some embodiments, the two-stage flow electromagnetic pilot valve includes a pilot valve body, a main inlet is provided on the side of the pilot valve body, an electromagnet and a valve core string are provided inside the pilot valve body, the main inlet is connected to the valve core string, the electromagnet is arranged opposite to the valve core string, and the output end of the electromagnet is connected to the power input end of the valve core string.

[0012] In some embodiments, there are two valve core strings, which are arranged side by side in the pilot valve body.

[0013] In some embodiments, a lever portion is provided between the output end of the electromagnet and the power input end of the valve core string. The lever portion is used to amplify the electromagnetic force output by the electromagnet, and the extension direction of the lever portion is perpendicular to the extension direction of the valve core string.

[0014] In some embodiments, the valve core string includes an inlet sleeve, a valve seat, and a through sleeve connected in sequence. An inlet port is provided between the inlet sleeve and the valve seat, and the inlet port is connected to the main inlet port. A working port for outputting the working medium is provided on the valve seat. A return port is provided between the valve seat and the through sleeve. A first spring is provided inside the inlet sleeve. A lower valve core is provided on the side of the first spring facing the through sleeve. The lower valve core can abut against the lower sealing surface of the valve seat. A support ring is provided inside the through sleeve. An upper valve core is provided on the side of the support ring facing the inlet sleeve. The upper valve core abuts against the upper sealing surface of the valve seat. A first push rod is provided between the upper valve core and the lower valve core. The first push rod can pass through the valve seat. A second push rod is provided inside the support ring. One end of the second push rod passes through the support ring and abuts against the upper valve core. The other end of the second push rod passes out from the end of the through sleeve.

[0015] In some embodiments, the valve core body of the lower valve core is cylindrical, and the end of the valve core body facing the valve seat is tapered.

[0016] In some embodiments, a second spring is further provided inside the liquid inlet sleeve. The cross-sectional dimension of the second spring is larger than that of the first spring. The valve core body of the lower valve core has a first step and a second step in the direction of the end of the liquid inlet sleeve. The first step abuts against the first spring, and the second step abuts against the second spring.

[0017] In some embodiments, the electromagnet includes a housing, with a lower end cover and an upper end cover respectively provided at both ends of the housing, an armature disposed inside the housing, and a lower coil and an upper coil disposed outside the armature, the lower coil and the upper coil having different numbers of turns.

[0018] One embodiment of this disclosure provides a hydraulic support assembly, including a hydraulic support, a jack, and the electromagnetic graded pressure regulating type electro-hydraulic speed control system for mining as described in any of the above embodiments, wherein the hydraulic cylinder is connected to the jack.

[0019] This embodiment utilizes an electromagnetic pilot valve with electromagnetic graded pressure regulation function to achieve proportional or graded output of high-pressure liquid to control the opening degree of the pilot valve, ultimately achieving different flow outputs from the pilot valve. This embodiment has a simple control method, requires minimal circuit modification, effectively reduces the number of parts in the electromagnetic pilot valve, and increases reliability.

[0020] To make the above-described objects, features and advantages of the embodiments of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0021] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with or without letter suffixes may indicate different instances of similar parts. The drawings illustrate various embodiments generally by way of example rather than limitation and are used, together with the description and claims, to illustrate the disclosed embodiments. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method. The accompanying drawings, which are provided to further understand embodiments of this disclosure and form part of this application, are illustrative embodiments of this disclosure and their descriptions are used to explain embodiments of this disclosure and do not constitute an undue limitation of the embodiments of this disclosure.

[0022] Figure 1 This is a schematic diagram of the structure of an electromagnetic graded voltage regulating type electro-hydraulic speed control system for mining, according to one embodiment of the present disclosure.

[0023] Figure 2 This is a second schematic diagram of the structure of an electromagnetic graded voltage regulating type electro-hydraulic speed control system for mining, according to one embodiment of this disclosure.

[0024] Figure 3 This is a schematic diagram of the structure of a two-stage flow pilot valve in an electromagnetic graded pressure regulating type electro-hydraulic speed control system for mining, according to one embodiment of the present disclosure.

[0025] Figure 4 yes Figure 3 A schematic diagram of the valve core string in a two-stage flow pilot valve and schematic diagrams of different states;

[0026] Figure 5 yes Figure 3 A schematic diagram of the structure of another valve core string in a two-stage flow pilot valve and schematic diagrams of different states;

[0027] Figure 6 This is a schematic diagram of the electromagnet structure in an electromagnetic graded voltage regulating type electrohydraulic speed control system for mining, according to one embodiment of this disclosure.

[0028] Figure label:

[0029] 1-Pilot valve body; 2-Valve core string; 201-Liquid sleeve; 202-Support ring; 203-Upper valve core; 204-First push rod; 205-Valve seat; 206-Lower valve core; 207-First spring; 208-Liquid inlet sleeve; 209-Second spring; 210-Second push rod; 3-Enlarged section; 4-Electromagnet; 401-Housing; 402-Lower end cover; 403-Lower coil; 404-Upper coil; 405-Armature; 406-Upper end cover; 11-Hydraulic cylinder; 11a-None 11b - Rod chamber; 21 - First directional valve; 31 - Second directional valve; 41 - Filter device; 51 - First check valve; 52 - Second check valve; 71 - First solenoid switch valve; 72 - Second solenoid pilot valve; 81 - Controller; 110 - First pipeline; 120 - Second pipeline; 101 - First inlet pipeline; 102 - First return pipeline; 103 - Second inlet pipeline; 104 - Second return pipeline; 601 - First step; 602 - Second step. Detailed Implementation

[0030] The specific embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings, but these are not intended to limit the scope of the present disclosure.

[0031] It should be understood that various modifications can be made to the embodiments disclosed herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of the embodiments disclosed will be apparent to those skilled in the art.

[0032] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present disclosure and, together with the general description of the embodiments of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the embodiments of the present disclosure.

[0033] These and other features of the embodiments of this disclosure will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0034] It should also be understood that although embodiments of the present disclosure have been described with reference to specific examples, those skilled in the art can certainly implement many other equivalent forms of the embodiments of the present disclosure, which have the features as described in the claims and are therefore all within the scope of protection defined herein.

[0035] The above and other aspects, features and advantages of embodiments of the present disclosure will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0036] Specific embodiments of the present disclosure are described thereafter with reference to the accompanying drawings; however, it should be understood that the disclosed embodiments are merely examples of embodiments of the present disclosure, which may be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that would obscure the embodiments of the present disclosure. Therefore, the specific structural and functional details disclosed herein are not intended to be limiting, but merely to serve as the basis and representative basis for the claims to teach those skilled in the art to use the embodiments of the present disclosure in a variety of substantially any suitable detailed structures.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in still another embodiment,” all of which may refer to one or more of the same or different embodiments according to the present disclosure.

[0039] This disclosure provides an electromagnetic graded voltage regulating type electro-hydraulic speed control system for mining applications, such as... Figures 1-6 As shown, it includes a system inlet P, a system return R, a hydraulic cylinder 11, a valve assembly, and a controller 81. The hydraulic cylinder 11 includes a rodless chamber 11a and a rod chamber 11b, which are separated by a piston. A piston rod is connected to the piston and passes through the rod chamber 11b. The piston rod is connected to an actuator (e.g., a jack), so that the movement of the piston rod drives the movement of the jack, which in turn drives the movement of the hydraulic support.

[0040] Furthermore, the valve assembly includes a first reversing valve 21, a second reversing valve 31, a first electromagnetic pilot valve 71, and a second electromagnetic pilot valve 72. In this embodiment, the first reversing valve 21 is a two-stage flow reversing valve, and the first electromagnetic pilot valve 71 is a two-stage flow electromagnetic pilot valve.

[0041] Specifically, the system inlet P is connected to the inlet of the first reversing valve 21 and the inlet of the second reversing valve 31 via the first inlet pipe 101, the outlet of the first reversing valve 21 is connected to the rodless chamber 11a, and the outlet of the second reversing valve 31 is connected to the rod chamber 11b; the system return end R is connected to the return port of the first reversing valve 21 and the return port of the second reversing valve 31 via the first return pipe 102.

[0042] To control the first electromagnetic pilot valve 71 and the second electromagnetic pilot valve 72, the controller 81 is connected to the control terminals of the first electromagnetic pilot valve 71 and the second electromagnetic pilot valve 72. The system inlet P is connected to the inlet of the first electromagnetic pilot valve 71 and the inlet of the second electromagnetic pilot valve 72 via the second inlet pipe 103, and the system return end R is connected to the return port of the first electromagnetic pilot valve 71 and the return port of the second electromagnetic pilot valve 72 via the second return pipe 104.

[0043] Furthermore, the outlet of the first electromagnetic pilot valve 71 is connected to the control chamber of the first directional valve 21 through the first pipeline 110, and the outlet of the second electromagnetic pilot valve 72 is connected to the control chamber of the second directional valve 31 through the second pipeline 120.

[0044] Furthermore, a filter device 41 is provided on the second liquid inlet pipeline 103. The filter device 41 is particularly located between the liquid inlet P of the system and the liquid inlet of the first electromagnetic pilot valve 71 and the second electromagnetic pilot valve 72. The filter device 41 can filter the liquid inlet. A first check valve 51 is provided between the liquid inlet P of the system and the filter device 41. Here, the first check valve 51 ensures the flow direction of the liquid inlet and prevents backflow.

[0045] Furthermore, a second check valve 52 is provided on the second return line 104. The second check valve 52 is particularly located between the return end R of the system and the return port of the first electromagnetic pilot valve 71 and the second electromagnetic pilot valve 72. Here, the second check valve 52 ensures the flow direction of the return liquid and prevents backflow.

[0046] The electromagnetic graded pressure regulating type electro-hydraulic speed control system for mining described in this embodiment can realize functions such as slow extension, rapid extension, and retraction of the piston rod in the hydraulic cylinder, wherein:

[0047] When a slow extension of the piston rod in the hydraulic cylinder is required: a small current signal is applied to the first electromagnetic pilot valve 71 through the controller 81, and a portion of the high-pressure liquid input at the system inlet P flows back to the system return end R after passing through the throttling position of the first electromagnetic pilot valve 71 and then through the second check valve 51, while the remaining portion of the high-pressure liquid flows into the control chamber of the first directional valve 21.

[0048] At this time, the control chamber of the first directional valve 21 can only reach a preset pressure Pc. Under the preset pressure Pc, the return valve core of the first directional valve 21 is closed, while the inlet valve core is opened at a small flow rate to supply fluid to the rodless chamber 11a of the hydraulic cylinder 11. Simultaneously, since both the second solenoid pilot valve 72 and the second directional valve 31 are in the return position, the rod chamber 11b of the hydraulic cylinder 11 is returned to fluid, causing the piston in the hydraulic cylinder 11 to slowly extend the piston rod outward. The output flow rate of the first directional valve 21 can be controlled by adjusting the shape and size of the valve core, thereby controlling the movement speed of the piston in the hydraulic cylinder 11.

[0049] When the piston rod in the hydraulic cylinder needs to extend quickly, the controller 81 applies a large current signal to the first electromagnetic pilot valve 71. After the high-pressure liquid input at the system inlet P is in the working position with a large opening through the first electromagnetic pilot valve 71, all the high-pressure liquid flows into the control chamber of the first directional valve 21.

[0050] At this time, the control chamber of the first directional valve 21 reaches the system pressure P0. Under the action of the system pressure P0, the first directional valve 21 fully opens to achieve a large flow rate of fluid supply to the rodless chamber 11a of the hydraulic cylinder 11. Simultaneously, since both the second solenoid pilot valve 72 and the second directional valve 31 are in the return position, the rod chamber 11b of the hydraulic cylinder 11 returns fluid, causing the piston in the hydraulic cylinder 11 to rapidly extend the piston rod outward. The output flow rate of the first directional valve 21 can be controlled by adjusting the shape and size of the valve core, thereby controlling the movement speed of the piston in the hydraulic cylinder 11.

[0051] When the piston rod in the hydraulic cylinder needs to retract: the controller 81 opens the second electromagnetic pilot valve 72, and the high-pressure fluid flowing into the second electromagnetic pilot valve 72 from the system inlet P enters the control chamber of the second directional valve 31. The control chamber of the second directional valve 31 is pressurized to the system pressure P0, so that the second directional valve 31 is fully open. The rod chamber 11b of the hydraulic cylinder 11 enters the high-pressure fluid, and the rodless chamber 11a is connected to the system return end R through the first directional valve 21, so that the piston in the hydraulic cylinder 11 retracts.

[0052] In the above embodiments, the rapid or slow extension of the piston rod of the hydraulic cylinder 11 mainly relies on the first directional valve 21. In some embodiments, such as... Figure 2 As shown, the second electromagnetic pilot valve 72 can also be a two-stage flow electromagnetic pilot valve, which can realize the fast and slow action adjustment of the piston rod in the hydraulic cylinder, especially during the retraction process. For the specific adjustment process, please refer to the above description of the fast and slow extension of the piston rod.

[0053] Another embodiment of this disclosure provides a two-stage flow electromagnetic pilot valve, such as Figure 3 As shown, it includes a pilot valve body 1, a main liquid inlet is provided on the side of the pilot valve body 1, and a valve core string 2 is provided inside the pilot valve body 1. Liquid enters into the valve core string 2 through the liquid inlet. Here, there are two valve core strings 2, which are arranged side by side in the pilot valve body 1. The main liquid inlet is connected to the valve core string 2.

[0054] Furthermore, an electromagnet 4 is also provided inside the pilot valve body 1. The electromagnet 4 is arranged opposite to the valve core string 2. The output end of the electromagnet 4 is connected to the power input end of the valve core string 2. The output end of the electromagnet 4 outputs electromagnetic force to drive the valve cores in the valve core string 2 to move. Preferably, a lever part 3 is provided between the output end of the electromagnet 4 and the power input end of the valve core string 2. The lever part 3 is used to amplify the electromagnetic force output by the electromagnet 4. Here, the lever part 3 is used to connect to the two valve core strings 2 respectively, wherein the extension direction of the lever part 3 is perpendicular to the extension direction of the valve core string 2.

[0055] Specifically, such as Figure 4 As shown, the valve core string 2 includes an inlet sleeve 208, a valve seat 205, and a through sleeve 201 connected in sequence. A first spring 207 is provided inside the inlet sleeve 208. A lower valve core 206 is provided on the side of the first spring 207 facing the through sleeve 201. The lower valve core 206 can abut against one side (lower sealing surface) of the valve seat 205. The valve core body of the lower valve core 206 is cylindrical, and the end of the valve core body facing the valve seat 205 is tapered.

[0056] Furthermore, a support ring 202 is provided inside the liquid-passing sleeve 201, and an upper valve core 203 is provided on the side of the support ring 202 facing the liquid-passing sleeve 208. The upper valve core 203 abuts against the other side (upper sealing surface) of the valve seat 205, wherein the end of the upper valve core 203 facing the valve seat 25 is tapered; a first push rod 204 is provided between the upper valve core 203 and the lower valve core 206, and the first push rod 204 can pass through the valve seat 205.

[0057] In addition, a second push rod 210 is provided inside the support ring 202. One end of the second push rod 210 passes through the support ring 202 and abuts against the upper valve core 203, while the other end passes through the liquid sleeve 201 and is used to receive electromagnetic force.

[0058] In this embodiment, an inlet port, namely port P, is provided between the inlet sleeve 208 and the valve seat 205. The inlet port P is connected to the main inlet port. A working port, namely port A, is provided on the valve seat 205. The working port A is used to output the working medium. In the above embodiment, it is the outlet of the first electromagnetic pilot valve 71 or the second electromagnetic pilot valve 72. A return port, namely port T, is provided between the valve seat 205 and the liquid-passing sleeve 201.

[0059] The working principle of the two-stage flow electromagnetic pilot valve in this embodiment is as follows: by applying different voltages / currents to the electromagnet 4, the generated electromagnetic force and spring force are balanced, thereby achieving the purpose of adjusting the opening degree of the electromagnetic pilot valve. Specifically, when the two-stage flow electromagnetic pilot valve has suitable structural parameters, the hydraulic pressure on the valve core string 2 is the same in all directions, resulting in force balance. The upper valve core 22 and the lower valve core 26 only move under the action of electromagnetic force and spring force.

[0060] Specifically, the two-stage flow electromagnetic pilot valve operates as follows: When the electromagnet 4 is not energized, the lower valve core 206 in the valve core string 2 is only subjected to the spring force of the first spring 207 and forms a seal with the lower sealing surface of the valve seat 205, while the upper valve core 203 disengages from the upper sealing surface of the valve seat 205 and achieves maximum separation from it; when the electromagnet 4 is energized, the valve core string 2 is subjected to the combined action of spring force and electromagnetic force, and as the voltage / current increases... As the electromagnetic force gradually increases, it pushes the upper valve core 203 and the lower valve core 206 toward the first spring 207 and compresses the first spring 207. As a result, the spring force of the first spring 207 also increases. During this process, the separation between the lower valve core 206 and the lower sealing surface of the valve seat 205 gradually increases, while the upper valve core 203 and the upper sealing surface of the valve seat 205 gradually approach each other and the opening decreases, until the upper valve core 203 and the upper sealing surface of the valve seat 205 are in contact so that the electromagnetic pilot valve is fully opened.

[0061] Furthermore, there are multiple intermediate positions during the process of increasing the voltage through the electromagnet 4. When the upper valve core 203 and the lower valve core 206 are separated from the upper sealing surface and the lower sealing surface of the valve seat 205, respectively, a portion of the high-pressure liquid input through the inlet port (P port) enters the working port (A port) and a portion enters the return port (T port). That is, the pressure formed at the working port (A port) increases with the increase of voltage / current, thereby achieving the purpose of adjusting the pressure.

[0062] Specifically, when the electromagnet 4 outputs a suitable voltage / current range, the pressure at the working port, i.e., port A, causes the first reversing valve 21 and the second reversing valve 22 to be in a throttling state; in a higher voltage / current range, the pressure at the working port, i.e., port A, causes the first reversing valve 21 or the second reversing valve 22 to be in a fully open state.

[0063] The electromagnet 4 mentioned here can be a proportional electromagnet combined with a continuous voltage / current regulating circuit to achieve stepless adjustment of the output flow of the electromagnetic pilot valve; of course, it can also be combined with a step-by-step circuit, that is, a predetermined voltage / current value is set to correspond to the required half-open state, and another predetermined voltage / current value is set to correspond to the fully open state. During control, it is only necessary to control the electromagnet 4 to switch between these two voltage / current values.

[0064] like Figure 5 As shown, in another embodiment, the difference from the above embodiment is that the liquid inlet sleeve 208 is also provided with a second spring 209 and the structure of the lower valve core 206 is different. Here, the cross-sectional dimension of the second spring 209 is larger than the cross-sectional dimension of the first spring 207.

[0065] In this embodiment, the valve core body of the lower valve core 206 has a first step 601 and a second step 602 in the direction of the end of the liquid inlet sleeve 208. The first step 601 abuts against the first spring 207, and the second step 602 abuts against the second spring 209.

[0066] When the electromagnet 4 is in the closed state, the force F applied by the electromagnet 4 to the valve core string 2 is 0, and the valve core string 2 moves under the action of the force f of the first spring 207. The lower valve core 206 and the lower sealing surface of the valve seat 205 are in contact to form a seal. At this time, the lower valve core 206 and the second spring 209 are not in contact, and the second spring 209 does not generate spring force.

[0067] When the electromagnetic force F is greater than the compressive force f of the first spring 207, it pushes the valve core string 2 to move toward the first spring 207, causing the lower valve core 206 to separate from the lower sealing surface of the valve seat 205, until the second step of the lower valve core 206 contacts the second spring 209 and compresses the second spring 209.

[0068] When the electromagnetic force F is greater than the compressive force f of the first spring 207 but insufficient to further compress the second spring 209, the valve core string 2 is in a half-open state; when the electromagnetic force F is greater than the sum of the spring forces of the first spring 207 and the second spring 209, the valve core string 2 is in a fully open state. In this way, by using two springs to achieve a step-by-step change in the driving force required for the valve core string to be in the half-open and fully open states, it is easier to achieve graded opening of the electromagnetic pilot valve and reduce the control difficulty.

[0069] In another embodiment, such as Figure 6 As shown, the electromagnet 4 includes a housing 401, with a lower end cover 402 and an upper end cover 406 respectively at its two ends. An armature 405 is disposed inside the housing 401, and a lower coil 403 and an upper coil 404 are disposed outside the armature 405. In this embodiment, two coils are used to generate excitation current and provide electromagnetic force. When one of the lower coil 403 or the upper coil 404 is energized, a driving force Flarge is generated; when both coils are energized simultaneously, a driving force Fsmall is generated. By reasonably setting the number of turns of the two coils, it can be ensured that flarge + fsmall > Fsmall > fsmall, and Flarge > flarge + fsmall.

[0070] Considering that existing technologies typically only provide one input voltage, switching between different voltages requires a transformer circuit and a switching circuit. The above-mentioned technical solution avoids voltage transformation by using two coils, achieving two driving force outputs with only one voltage input. In this embodiment, the voltage adjustment method using one coil is replaced by controlling the energization of two coils to change the driving force of the electromagnet, ultimately controlling the output hydraulic pressure of the solenoid pilot valve. Therefore, the pressure in the control chamber of the two-stage flow reversing valve is controlled by a combination of two-stage flow solenoid pilot valves to regulate the flow rate of the two-stage flow reversing valve. A large flow rate is used for control when the hydraulic cylinder requires rapid extension or retraction of the piston rod, while a small flow rate is used for precise position control.

[0071] This embodiment utilizes an electromagnetic pilot valve with electromagnetic graded pressure regulation function to achieve proportional or graded output of high-pressure liquid to control the opening degree of the pilot valve, ultimately achieving different flow outputs from the pilot valve. This embodiment has a simple control method, requires minimal circuit modification, effectively reduces the number of parts in the electromagnetic pilot valve, and increases reliability.

[0072] Another embodiment of this disclosure provides a hydraulic support assembly, which includes a hydraulic support, a jack, and an electromagnetic graded pressure regulating mine electro-hydraulic speed control system as described in any of the above embodiments. The logic combination controls the mine electro-hydraulic speed control system to drive the movement of the jack, thereby driving the movement of the hydraulic support through the jack.

[0073] This embodiment utilizes an electromagnetic pilot valve with electromagnetic graded pressure regulation function to achieve proportional or graded output of high-pressure liquid to control the opening degree of the pilot valve, ultimately achieving different flow outputs from the pilot valve. This embodiment has a simple control method, requires minimal circuit modification, effectively reduces the number of parts in the electromagnetic pilot valve, and increases reliability.

[0074] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0075] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0076] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electromagnetic graded voltage regulating type electro-hydraulic speed control system for mining, characterized in that, The system includes a system inlet, a system return, a hydraulic cylinder, a valve assembly, and a controller. The hydraulic cylinder includes a rodless chamber and a rod chamber. The valve assembly includes a first directional valve, a second directional valve, a first solenoid pilot valve, and a second solenoid pilot valve. The controller is connected to the control terminals of the first and second solenoid pilot valves, respectively. The system inlet is connected to the inlets of the first, second, first, and second solenoid pilot valves, respectively. The outlet of the first solenoid pilot valve is connected to the... The control chambers of the first and second directional control valves are connected, and their outlets are respectively connected to the rodless chamber and the rod chamber. The first directional control valve is a two-stage flow control valve, and the first solenoid pilot valve is also a two-stage flow solenoid pilot valve. The second directional control valve is also a two-stage flow control valve, and the second solenoid pilot valve is also a two-stage flow solenoid pilot valve. The two-stage flow solenoid pilot valve includes a pilot valve body, a main inlet is provided on the side of the pilot valve body, and an electromagnet is provided inside the pilot valve body. The system comprises a valve core string, a main inlet connected to the valve core string, an electromagnet positioned opposite the valve core string, and an output terminal connected to the power input terminal of the valve core string. The valve core string includes an inlet sleeve, a valve seat, and a through sleeve connected in sequence. An inlet is provided between the inlet sleeve and the valve seat, and the inlet is connected to the main inlet. The valve seat has a working port for outputting the working medium, and a return port is provided between the valve seat and the through sleeve. A first spring is installed inside the inlet sleeve. A lower valve core is provided on one side of the liquid-passing sleeve, which abuts against the lower sealing surface of the valve seat. A support ring is provided inside the liquid-passing sleeve, and an upper valve core is provided on the side of the support ring facing the liquid-inlet sleeve, which abuts against the upper sealing surface of the valve seat. A first push rod is provided between the upper valve core and the lower valve core, which can pass through the valve seat. A second push rod is provided inside the support ring, with one end of the second push rod passing through the support ring and abutting against the upper valve core, and the other end passing out from the end of the liquid-passing sleeve.

2. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 1, characterized in that, The system's return port is connected to the return ports of the first reversing valve, the second reversing valve, the first electromagnetic pilot valve, and the second electromagnetic pilot valve.

3. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 2, characterized in that, The system inlet is connected to the inlet of the first directional valve and the inlet of the second directional valve via a first inlet pipe. The return ports of the first and second directional valves are connected to the system return end via a first return pipe. The system inlet is connected to the inlet of the first and second electromagnetic pilot valves via a second inlet pipe. The return ports of the first and second electromagnetic pilot valves are connected to the system return end via a second return pipe.

4. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 3, characterized in that, The outlet of the first electromagnetic pilot valve is connected to the control chamber of the second directional valve through a first pipeline, and the outlet of the second electromagnetic pilot valve is connected to the control chamber of the second directional valve through a second pipeline.

5. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 3, characterized in that, A filter device and a first check valve are installed on the second inlet pipeline. The filter device is located between the system inlet and the inlet of the first electromagnetic pilot valve and the second electromagnetic pilot valve. The first check valve is located between the system inlet and the filter device.

6. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 3, characterized in that, A third check valve is provided on the second return line. The third check valve is located between the return end of the system and the return ports of the first electromagnetic pilot valve and the second electromagnetic pilot valve.

7. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 1, characterized in that, There are two valve core strings, which are arranged side by side in the pilot valve body.

8. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 1, characterized in that, A lever is provided between the output end of the electromagnet and the power input end of the valve core string. The lever is used to amplify the electromagnetic force output by the electromagnet, and the extension direction of the lever is perpendicular to the extension direction of the valve core string.

9. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 1, characterized in that, The valve core body of the lower valve core is cylindrical, and the end of the valve core body facing the valve seat is tapered.

10. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mining as described in claim 1, characterized in that, A second spring is also provided inside the liquid inlet sleeve. The cross-sectional dimension of the second spring is larger than that of the first spring. The valve core body of the lower valve core has a first step and a second step in the direction of the end of the liquid inlet sleeve. The first step abuts against the first spring, and the second step abuts against the second spring.

11. The electromagnetic graded voltage regulating type electro-hydraulic speed control system for mines according to claim 7, characterized in that, The electromagnet includes a housing, with a lower end cover and an upper end cover respectively at both ends of the housing. An armature is disposed inside the housing, and a lower coil and an upper coil are disposed outside the armature. The lower coil and the upper coil have different numbers of turns.

12. A hydraulic support assembly, characterized in that, It includes a hydraulic support, a jack, and the electromagnetic graded pressure regulating type electro-hydraulic speed control system for mining as described in any one of claims 1-11, wherein the hydraulic cylinder is connected to the jack.

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