A liquid supply device and control method thereof, a hydraulic system and a safety valve detection system

Abstract

The present invention discloses a liquid supply device and a control method thereof, a hydraulic system and a safety valve detection system, which can output high-pressure liquid with a constant flow rate. The liquid supply device includes a liquid tank, a liquid supply pipeline, a loading device, a first valve and a second valve. Among them, the liquid supply pipeline has a liquid inlet and a liquid supply port. The loading device includes a plunger cylinder and a driving device. The plunger cylinder includes a plunger cylinder barrel and a piston that slides with the working chamber of the plunger cylinder barrel, and the piston is connected to a first piston rod. The liquid tank is connected to the working chamber of the plunger cylinder barrel through a liquid inlet pipeline, and the liquid inlet of the liquid supply pipeline is connected to the working chamber of the plunger cylinder barrel. The driving device includes a motor and a transmission assembly, and the transmission assembly can convert the rotation of the motor into the reciprocating motion of the first piston rod, and the transmission parts in the transmission assembly are all made of rigid materials. The first valve is connected in series to the liquid inlet pipeline. The second valve is connected in series to the liquid supply pipeline.

Description

Technical Field

[0001] The present invention relates to the field of hydraulic technology, and in particular to a liquid supply device and a control method thereof, a hydraulic system and a safety valve detection system. Background Art

[0002] A hydraulic system is a device that uses liquid as a working medium and utilizes the pressure of the liquid to achieve power output. In the prior art, it is necessary to provide the emulsion system with a liquid with a pressure of more than 60MPa and an adjustable flow rate. Figure 1 The liquid supply equipment generally includes a liquid tank a, a liquid pump b, a motor c, a reversing valve d, a speed regulating valve e and a booster cylinder f. The motor c drives the liquid pump b to provide hydraulic power, and the liquid flows into the speed regulating valve e through the reversing valve d. After the flow rate is adjusted by the speed regulating valve e, the liquid enters the low-pressure side of the booster cylinder f, pushing the piston of the booster cylinder f to move, and the pressure is increased through the area ratio of the pistons on the high-pressure side and the low-pressure side of the booster cylinder f.

[0003] However, when the speed control valve e adjusts the liquid flow, there are problems of low applicable pressure and poor micro-flow stability. In addition, when the flow is extremely small, the booster cylinder f is prone to creep, causing its output flow to fluctuate, resulting in the liquid supply equipment being unable to output high-pressure liquid with a constant flow. Summary of the invention

[0004] The object of the present invention is to provide a liquid supply device and a control method thereof, a hydraulic system and a safety valve detection system, which can output high-pressure liquid with a constant flow rate.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a liquid supply device. The liquid supply device includes a liquid tank, a liquid supply pipeline, a loading device, a first valve and a second valve. The liquid supply pipeline has a liquid inlet and a liquid supply port. The loading device includes a plunger cylinder and a driving device. The plunger cylinder includes a plunger cylinder barrel and a movable first piston rod that slides with the working chamber of the plunger cylinder barrel. The liquid tank is connected to the working chamber of the plunger cylinder barrel through a liquid inlet pipeline, and the liquid inlet of the liquid supply pipeline is connected to the working chamber of the plunger cylinder barrel. The driving device includes a motor and a transmission assembly, and the transmission assembly can convert the rotation of the motor into the reciprocating motion of the first piston rod, and the transmission parts in the transmission assembly are all made of rigid materials. The first valve is connected in series to the liquid inlet pipeline. The second valve is connected in series to the liquid supply pipeline.

[0006] Compared with the prior art, in the liquid supply device adopted by the present invention, the loading device includes a plunger cylinder and a driving device, and the plunger cylinder includes a plunger cylinder barrel and a first piston rod that slides with the working chamber of the plunger cylinder barrel. The driving device includes a motor and a transmission assembly, and the transmission assembly can convert the rotation of the motor into the reciprocating motion of the first piston rod. At the same time, the liquid tank is connected to the working chamber of the plunger cylinder barrel through a liquid inlet pipe, so that when the driving device drives the first piston rod to extend out of the plunger cylinder barrel, the volume of the working chamber of the plunger cylinder barrel gradually increases, thereby forming a negative pressure area in the working chamber of the plunger cylinder barrel. At this time, the working liquid in the liquid tank can enter the working chamber of the plunger cylinder barrel through the liquid inlet pipe under the action of atmospheric pressure.

[0007] Then, because the working chamber of the plunger cylinder is connected to the liquid supply pipeline, the first valve is connected in series to the liquid inlet pipeline, and the second valve is connected in series to the liquid supply pipeline, when the driving device drives the first piston rod to retract into the working chamber of the plunger cylinder, the volume of the working chamber of the plunger cylinder becomes smaller, so that the pressure of the working liquid in the working chamber of the plunger cylinder increases. The first valve is closed and the second valve is opened, so that the working liquid in the working chamber of the plunger cylinder can flow to the liquid supply port through the liquid supply pipeline for liquid supply.

[0008] It can be seen that in the liquid supply device provided by the present application, the rotation of the motor is converted into the reciprocating motion of the first piston rod mainly through the transmission assembly, and the thrust of the first piston rod is used to generate the liquid pressure. Since the transmission parts in the transmission assembly are all made of rigid materials, the transmission assembly has good speed transmission performance. At this time, the first piston rod and the piston have high speed regulation performance and high speed rigidity. Therefore, when the liquid supply demand is small, the plunger cylinder will not creep, and can provide high-pressure liquid with a constant flow rate.

[0009] The present invention also provides a liquid supply method of a liquid supply device, and the control method of the liquid supply device comprises:

[0010] Preliminary step: enabling the first group of loading devices to perform a liquid aspiration operation;

[0011] The liquid suction operation includes: controlling the motor to rotate in a first direction to move the first piston rod from a first position to a second position, wherein when the first piston rod is in the first position, the lower end of the first piston rod is flush with the bottom of the working chamber of the hydraulic cylinder, and when the first piston rod is in the second position, the lower end of the first piston rod is flush with the top of the working chamber of the hydraulic cylinder;

[0012] A first liquid supplying step: causing the first group of loading devices to perform a liquid supplying operation, while causing the second group of loading devices to perform a liquid aspirating operation;

[0013] The liquid supply operation includes: controlling the motor to rotate in a second direction to move the first piston rod from the second position to the first position; wherein the second direction is opposite to the first direction;

[0014] A second liquid supplying step: causing the first group of loading devices to perform a liquid aspiration operation, while causing the second group of loading devices to perform a liquid supplying operation;

[0015] Repeating step: Repeat the first liquid supplying step and the second liquid supplying step until the liquid supplying is completed.

[0016] Compared with the prior art, the beneficial effects of the control method provided by the present invention are the same as the beneficial effects of the above-mentioned liquid supply device, which will not be described in detail here.

[0017] The present invention also provides a hydraulic system, comprising the above-mentioned fluid supply device and an actuator device, wherein the fluid supply port of the fluid supply device is connected to the fluid inlet port of the actuator device.

[0018] Compared with the prior art, the beneficial effects of the hydraulic system provided by the present invention are the same as the beneficial effects of the above-mentioned fluid supply device, which will not be elaborated here.

[0019] The present invention also provides a safety valve detection system, which includes the above-mentioned liquid supply device, wherein the liquid supply port of the liquid supply device is connected to the liquid inlet of the safety valve.

[0020] Compared with the prior art, the beneficial effects of the safety valve detection system provided by the present invention are the same as the beneficial effects of the above-mentioned liquid supply equipment, which will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 It is a structural schematic diagram of a hydraulic device in the prior art;

[0023] Figure 2 One of the structural schematic diagrams of the liquid supply device provided in the embodiment of the present invention;

[0024] Figure 3 A schematic diagram of the structure of a loading device provided in an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of the structure of a driving device provided by an embodiment of the present invention;

[0026] Figure 5 A second structural schematic diagram of a liquid supply device provided in an embodiment of the present invention;

[0027] Figure 6 One of the flow charts of the control method of the liquid supply device provided by the embodiment of the present invention;

[0028] Figure 7 A second flowchart of a method for controlling a liquid supply device provided in an embodiment of the present invention;

[0029] Figure 8 Flow chart 3 of the control method of the liquid supply device provided in the embodiment of the present invention;

[0030] Fig. 9 Flow chart 4 of the control method of the liquid supply device provided in the embodiment of the present invention;

[0031] Fig.10 A schematic diagram of the structure of a hydraulic system provided by an embodiment of the present invention;

[0032] Fig.11 A schematic structural diagram of a safety valve detection system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0037] An embodiment of the present invention provides a liquid supply device. Figure 2 The schematic diagram of the structure of the liquid supply device is shown. Figure 3 A schematic structural diagram of a middle loading device of the liquid supply device is shown. Figure 4 The schematic diagram of the structure of the electric cylinder in the above-mentioned loading device is shown. Figure 2 to Figure 4 The liquid supply device includes a liquid tank 100, a liquid supply pipeline 200, a loading device 300, a liquid inlet pipeline 400, a first valve 500 and a second valve 600.

[0038] The liquid supply pipeline 200 has a liquid inlet 210 and a liquid supply port 220 .

[0039] The loading device 300 includes a plunger cylinder 310 and a driving device 320. The plunger cylinder 310 includes a plunger cylinder barrel 311 and a first piston rod 312 that slides with the working chamber of the plunger cylinder barrel 311. It should be noted that the plunger cylinder barrel 311 includes a cylinder barrel body and a front cylinder cover, and the front cylinder cover is arranged at the end of the cylinder barrel body. The first piston rod 312 is located in the working chamber of the plunger cylinder barrel 311, and the first end of the first piston rod 312 slides with the working chamber of the plunger cylinder barrel, and the second end of the first piston rod 312 extends out of the plunger cylinder barrel 311 through the front cylinder cover and is connected to the transmission assembly.

[0040] The liquid tank 100 is in communication with the working chamber of the plunger cylinder 311 through the liquid inlet pipe 400, and the liquid inlet port 210 of the liquid supply pipe 200 is in communication with the working chamber of the plunger cylinder 311. It should be understood that in order to make the plunger cylinder 311 communicate with both the liquid inlet pipe 400 and the liquid supply pipe 200, two openings in communication with the working chamber of the plunger cylinder 311 can be provided on the plunger cylinder 311, and one opening is in communication with the liquid inlet port 210 of the liquid supply pipe 200, and the other opening is in communication with the liquid inlet pipe 400. Of course, it is also possible to provide an opening in communication with the working chamber of the plunger cylinder 311 on the plunger cylinder 311, and make both the liquid inlet pipe 400 and the liquid inlet port 210 of the liquid supply pipe 200 communicate with the opening.

[0041] The driving device 320 includes a motor 321 and a transmission assembly, and the transmission assembly can convert the rotation of the motor 321 into the reciprocating motion of the first piston rod 312, and the transmission parts in the transmission assembly are all made of rigid materials. It should be understood that when the above-mentioned first piston rod 312 reciprocates, the volume of the working chamber of the plunger cylinder 311 will change. It should be noted that the above-mentioned transmission assembly can be selected according to actual conditions. For example, the above-mentioned transmission assembly can be a turbine worm structure, and the turbine worm structure includes a worm wheel and a worm that cooperate with each other, so that the worm wheel is coaxially fixed to the output shaft of the motor 321, and the worm is coaxially fixed to the first piston rod 312.

[0042] The first valve 500 is connected in series to the liquid inlet pipe 400 . The second valve 600 is connected in series to the liquid supply pipe 200 .

[0043] When the above-mentioned liquid supply device is supplying liquid, the first piston rod 312 is first located in the working chamber of the plunger cylinder 311. Then the loading device 300 performs the liquid suction operation. The liquid suction operation is specifically: controlling the motor 321 to rotate so that the transmission assembly drives the first piston rod 312 to move out of the working chamber of the plunger cylinder 311, so that the volume of the working chamber of the plunger cylinder 311 gradually increases. At this time, a negative pressure area is formed in the working chamber of the plunger cylinder 311, so that the first valve 500 is opened and the second valve 600 is closed. Then the liquid in the liquid tank 100 enters the working chamber of the plunger cylinder 311 under the action of atmospheric pressure. When the first piston rod 312 moves to the uppermost end of the working chamber of the plunger cylinder 311, the plunger cylinder 311 is filled with working liquid.

[0044] Then, the loading device 300 is controlled to perform the liquid supply operation. The liquid supply operation is specifically as follows: the motor 321 rotates in the opposite direction, and the transmission assembly drives the first piston rod 312 to move into the working chamber of the plunger cylinder 311, so that the volume of the working chamber of the plunger cylinder 311 becomes smaller, thereby increasing the liquid pressure in the working chamber of the plunger cylinder 311, opening the second valve 600 and closing the first valve 500. The liquid in the working chamber of the plunger cylinder 311 flows to the liquid supply pipe 200 for liquid supply. When the first piston rod 312 moves to the bottom of the working chamber of the plunger cylinder 311, the liquid in the working chamber of the plunger cylinder 311 completely flows into the liquid supply pipe 200, and the liquid supply is completed.

[0045] Repeating the liquid aspiration and liquid supply operations can complete multiple liquid supplies.

[0046] It can be seen from the structure of the above-mentioned liquid supply device and the liquid supply method of the liquid supply device that in the liquid supply device used in the embodiment of the present invention, when the driving device 320 drives the first piston rod 312 to extend out of the plunger cylinder 311, the volume of the working chamber of the plunger cylinder 311 increases to form a negative pressure area. At this time, the liquid in the liquid tank 100 can enter the working chamber of the plunger cylinder 311 under the action of atmospheric pressure.

[0047] The driving device 320 drives the first piston rod 312 to retract, which reduces the volume of the working chamber of the plunger cylinder 311 and increases the pressure of the liquid in the working chamber of the plunger cylinder 311, so that the liquid in the working chamber of the plunger cylinder 311 can be supplied through the liquid supply pipe 200.

[0048] It can be seen that in the liquid supply device provided by the present application, the rotation of the motor 321 is mainly converted into the reciprocating motion of the first piston rod 312 through the transmission assembly, and the thrust of the first piston rod 312 is used to generate the liquid pressure. Since the transmission parts in the transmission assembly are all made of rigid materials, the transmission assembly has good speed transmission performance. At this time, the piston 312 has a high speed regulation performance and a high speed rigidity. Therefore, even if the liquid supply demand is small, there will be no creeping phenomenon, and high-pressure liquid with a constant flow rate can be provided.

[0049] It should be noted that the liquid supply flow rate can be controlled by the speed of the motor 321. When the liquid supply flow rate of the liquid supply device needs to be increased, the speed of the motor 321 can be increased. At this time, the speed of the first piston rod 312 moving increases, thereby increasing the liquid supply flow rate. When the liquid supply flow rate of the liquid supply device needs to be reduced, the speed of the motor 321 can be reduced. At this time, the speed of the first piston rod 312 moving decreases, thereby reducing the liquid supply flow rate.

[0050] In order to detect the pressure of the working fluid in the plunger cylinder, the liquid inlet of the liquid supply pipeline is provided with a first pressure detection device, which can detect the pressure of the working fluid in the plunger cylinder.

[0051] At the same time, in order to detect the liquid supply pressure of the liquid supply port 220, a second pressure detection device is provided on the liquid supply port 220 of the liquid supply pipeline.

[0052] As a possible implementation, see Figure 4 The driving device 320 is an electric cylinder, which includes a motor 321 , a ball screw 322 , an electric cylinder barrel 323 and a second piston rod 324 .

[0053] The ball screw 322 and the second piston rod 324 are both located in the working chamber of the electric cylinder 323. The ball screw 322 includes a screw 3221 and a ball nut 3222 threadedly connected to the screw 3221. The screw 3221 is coaxially fixed to the output shaft of the motor 321, so that the screw 3221 can rotate synchronously with the output shaft of the motor 321.

[0054] The ball nut 3222 is slidably connected to the working chamber of the electric cylinder 323 , and the working chamber of the electric cylinder 323 can guide the ball nut 3222 , so that the ball nut 3222 moves along the extension direction of the working chamber of the electric cylinder 323 .

[0055] The first end of the second piston rod 324 is fixedly connected to the ball nut 3222, so that the ball nut 3222 can drive the second piston rod 324 to reciprocate. At the same time, the second end of the second piston rod 324 extends out of the working chamber of the electric cylinder 323, and the second end of the second piston rod 324 is coaxially fixedly connected to the second end of the first piston rod 312, so that the second piston rod 324 can drive the first piston rod 312 to reciprocate. It should be noted that the second piston rod 324 is connected to the first piston rod 312 through a flange.

[0056] At this time, the ball screw 322 in the electric cylinder can convert the rotation of the motor 321 into the reciprocating motion of the second piston rod 324, thereby driving the first piston rod 312 to reciprocate. The ball nut 3222 and the screw rod 3221 in the ball screw 322 are both made of rigid materials, so the ball screw 322 has good transmission rigidity.

[0057] At the same time, since the speed and the number of revolutions per unit time of the motor 321 in the electric cylinder can be precisely controlled, the electric cylinder can accurately control the speed, displacement and thrust of the second piston rod 324 when in use. At this time, the speed, displacement and thrust of the first piston rod 312 during movement can also be precisely controlled according to the speed, displacement and thrust of the second piston rod 324, respectively, so that the liquid supply amount and liquid supply pressure of the liquid supply device can be precisely controlled.

[0058] Furthermore, in order to more accurately determine the liquid supply amount of the liquid supply device, a linear displacement sensor is provided in the above-mentioned electric cylinder 323, and the linear displacement sensor can obtain the displacement of the second piston rod 324, thereby more accurately obtaining the displacement of the first piston rod 312, and further more accurately obtaining the liquid supply amount of the liquid supply device.

[0059] As a possible implementation, a first flange 311A ​​is fixedly connected to the plunger cylinder 311, and is coaxially arranged with the first piston rod 312. It should be noted that the connection position of the first flange 311A ​​and the plunger cylinder 311 can be selected according to actual conditions, as long as the first flange 311A ​​is coaxially arranged with the first piston rod 312. For example, the first flange 311A ​​is fixedly connected to the front cylinder cover of the plunger cylinder 311.

[0060] The electric cylinder 323 is fixedly connected with a second flange 323A, and the second flange 323A is coaxially arranged with the second piston rod 324. It should be noted that the connection position of the second flange 323A and the electric cylinder 323 can be selected according to actual conditions, as long as the second flange 323A is coaxially arranged with the second piston rod 324. For example, the first flange 311A ​​is fixedly connected with the front cylinder cover of the electric cylinder 323.

[0061] The loading device 300 further includes a flange sleeve 330 , a first end of the flange sleeve 330 is connected to the first flange 311A, and a second end of the flange sleeve 330 is connected to the second flange 323A.

[0062] At this time, the electric cylinder 323 and the plunger cylinder 311 are connected by the flange sleeve 330, the first flange 311A ​​and the second flange 323A, which can ensure the integrity of the electric cylinder and the plunger cylinder 310 in the loading device and prevent the electric cylinder from being unable to normally drive the first piston rod 312 to reciprocate due to the effect of gravity.

[0063] At the same time, the electric cylinder 323 and the plunger cylinder 311 are connected by the flange sleeve 330, the first flange 311A ​​and the second flange 323A, so that the first piston rod 312 and the second piston rod 324 can be coaxially connected.

[0064] Furthermore, a stopper structure is provided between the first flange 311A ​​and the first end of the flange sleeve 330. A stopper structure is also provided between the second flange 323A and the second end of the flange sleeve 330. At this time, the stopper structure can be positioned when the first flange 311A ​​and the first end of the flange sleeve 330 are connected, and can also be positioned when the second flange 323A and the second end of the flange sleeve 330 are connected, further ensuring that the first flange 311A ​​and the second flange 323A are coaxially connected to the flange sleeve 330, and further ensuring that the first piston rod 312 and the second piston rod 324 are coaxially connected.

[0065] As a possible implementation, the first valve 500 is a one-way valve, and the first valve 500 only allows the working liquid in the liquid inlet pipe 400 to flow into the plunger cylinder 311. At this time, when the liquid supply device 300 performs the liquid suction operation, there is no need to separately control the opening and closing of the first valve 500. The first valve will open under the action of atmospheric pressure, so that the working liquid in the liquid tank 100 flows into the working chamber of the plunger cylinder 311.

[0066] The second valve 600 is a one-way valve, and the second valve 600 only allows the working liquid in the working chamber of the plunger cylinder 311 to flow into the liquid supply pipe 200. At this time, when the liquid supply device is supplying liquid, there is no need to control the second valve 600. When the plunger cylinder 310 performs the liquid supply operation, the second valve 600 will automatically open under the pressure of the working liquid in the working chamber of the plunger cylinder 311, so that the working liquid in the working chamber of the plunger cylinder 311 passes through the liquid supply pipe 200.

[0067] As an example, see Figure 5 The above-mentioned liquid supply device includes two groups of loading devices 300. The working chamber of the plunger cylinder 311 in each group of loading devices 300 is connected to the liquid inlet pipeline 400 through a first valve 500, and the working chamber of the plunger cylinder 311 in each group of loading devices is connected to the liquid supply pipeline 200 through a second valve 600.

[0068] At this time, the first group of loading devices and the second group of loading devices can supply liquid alternately, so that the liquid supply device can supply liquid continuously.

[0069] Implementation Plan 2

[0070] The present invention provides a liquid supply method for the above liquid supply device. Figure 6 and Figure 7 , the above-mentioned liquid supply method comprises:

[0071] S100: Preparatory step: The first group of loading devices 300 performs a liquid suction operation. At this time, the working chamber of the plunger cylinder 311 in the first group of loading devices 300 stores working liquid.

[0072] The liquid suction operation includes: controlling the motor 321 to rotate in the first direction to move the first piston rod 312 from the first position to the second position. When the first piston rod is in the first position, the first end of the first piston rod is flush with the bottom of the working chamber of the plunger cylinder. When the first piston rod is in the second position, the first piston rod is flush with the top of the working chamber of the plunger cylinder.

[0073] S200: A first liquid supplying step: causing the first group of loading devices 300 to perform a liquid supplying operation, while causing the second group of loading devices 300 to perform a liquid aspirating operation.

[0074] The liquid supply operation includes: controlling the motor 321 to rotate in the second direction to move the first piston rod 312 from the second position to the first position; wherein the second direction is opposite to the first direction.

[0075] S300: A second liquid supplying step: causing the first group of loading devices 300 to perform a liquid suction operation, while causing the second group of loading devices 300 to perform a liquid supplying operation.

[0076] S400: Repeating step: Repeating the first liquid supplying step and the second liquid supplying step until the liquid supplying is completed.

[0077] In the liquid supply method provided in this embodiment, when the first group of loading devices 300 supplies liquid, the second group of loading devices 300 absorbs liquid. When the second group of loading devices 300 absorbs liquid, the second group of loading devices 300 supplies liquid, and the two groups of loading devices 300 absorb and supply liquid alternately, so that the liquid supply device can continuously supply liquid.

[0078] In order to ensure that the liquid supply pressure of the liquid supply device remains unchanged when the liquid supply device continuously supplies liquid, refer to Figure 8 The above S200: first liquid supply step is specifically as follows:

[0079] S210: receiving position information of the piston 312 in the second group of loading devices 300;

[0080] Receiving the pressure of the working fluid in the working chamber of the plunger cylinder 311 in the second group of loading devices 300;

[0081] S220: The motor 321 in the first group of loading devices 300 rotates in the second direction at a first speed, and the motor 321 in the second group of loading devices 300 rotates in the first direction at a second speed; wherein the first speed is greater than the second speed.

[0082] S230: When the first piston rod 312 in the second group of loading devices 300 moves to the second position, the motor 321 in the second group of loading devices 300 stops rotating, and then gradually accelerates the rotation in the second direction, so that the motor 321 in the first group of loading devices 300 gradually decelerates the rotation in the second direction, and the sum of the speeds of the motors 321 in the two groups of loading devices 300 is the first speed, until the pressure of the working fluid in the working chamber of the plunger cylinder 311 in the second group of loading devices 300 reaches the critical pressure of the second valve. It should be noted that the second valve is a one-way valve, and the second valve does not open when the second valve is at the critical pressure.

[0083] At this time, during the entire liquid supply process, the rotation speeds of the first group of loading devices 300 and the second group of loading devices 300 along the second direction are both the first speed, thereby ensuring that the liquid supply flow rate of the loading devices 300 is stable.

[0084] For further information, see Fig. 9 , the above S300: the second liquid supply step is specifically:

[0085] S310: receiving displacement information of the piston 312 in the first group of loading devices 300;

[0086] Receiving the pressure of the working fluid in the working chamber of the plunger cylinder 311 in the first group of loading devices 300;

[0087] S320: causing the motor 321 in the second group of loading devices 300 to rotate in the second direction at a first speed, and causing the motor 321 in the first group of loading devices 300 to rotate in the first direction at a second speed; wherein the first speed is greater than the second speed;

[0088] S330: When the first piston rod 312 in the first group of loading devices 300 moves to the second position, the motor 321 in the first group of loading devices 300 stops rotating and then gradually accelerates in the second direction, and the motor 321 in the second group of loading devices 300 gradually decelerates in the second direction, and the sum of the speeds of the motors 321 in the two groups of loading devices 300 is the first speed, until the pressure of the working fluid in the working chamber of the plunger cylinder 311 in the first group of loading devices 300 reaches the critical pressure of the second valve.

[0089] Implementation Plan 3

[0090] Embodiment 2 of the present invention provides a hydraulic system. Figure 2 and Fig.10 The hydraulic system includes the above-mentioned fluid supply device A and the actuator device B, and the fluid supply port 220 of the fluid supply device A is connected to the fluid inlet of the actuator device B.

[0091] At this time, the high-pressure liquid provided by the liquid supply device A can drive the actuator B to perform linear motion and reciprocating motion.

[0092] It should be noted that the structure of the above-mentioned actuator B can be selected according to actual conditions, as long as the actuator B can convert the pressure of the high-pressure liquid into the power of linear motion or reciprocating motion.

[0093] For example, the actuating device B may be a hydraulic cylinder.

[0094] Compared with the prior art, the beneficial effects of the hydraulic system provided by the embodiment of the present invention are the same as the beneficial effects of the above-mentioned fluid supply device, which will not be elaborated here.

[0095] Implementation Plan 4

[0096] The opening pressure of the safety valve for hydraulic support will affect the support performance of the hydraulic support, and thus will be an important factor affecting the stability of the surrounding rock of the working face. If the opening pressure of the safety valve is too low, the working resistance of the column and the supporting jack will be insufficient, thus causing the mining pressure of the working face to appear. If the opening pressure is too high, the column and the jack will be damaged due to excessive working resistance and failure to overflow and release pressure in time.

[0097] According to national standards, the opening, overflow and closing characteristics of the safety valve must be sampled before the safety valve leaves the factory. However, during the inspection of the safety valve, the measured opening pressure, overflow maximum value, overflow minimum value, fluctuation pressure and closing pressure are different under different test flows and test pressures. During the inspection process, if the opening pressure of the safety valve is measured to be greater than the actual opening pressure of the safety valve, the columns, jacks and single hydraulic props will be damaged due to excessive working resistance and failure to overflow and relieve pressure in time. If the opening pressure of the safety valve is measured to be less than the actual closing pressure of the safety valve, the working resistance of the columns, jacks and single hydraulic props will be reduced, thereby affecting their support performance.

[0098] Therefore, in order to ensure the accuracy of the measured opening, overflow and closing characteristics of the safety valve, the above safety valve detection system should have a constant flow output characteristic. That is, when the load changes, the output flow of the liquid supply equipment in the safety valve detection system should remain unchanged as much as possible, otherwise it will affect the accuracy of the safety valve small flow opening, overflow and closing characteristic test results.

[0099] In the existing safety valve detection system, the hydraulic pump station of the hydraulic system is mainly used as the hydraulic source to supply fluid to the safety valve. However, when the safety valve is opened for pressure testing, the flow rate of the experimental fluid is required to be 0.04L / min, and the pressure fluctuation value of the experimental fluid is required to be no more than ±5%. The output flow rate of the hydraulic pump is much greater than 0.04L / min, so a booster is connected in series to the hydraulic pump station. The booster can further increase the fluid supply pressure of the fluid supply equipment and reduce the fluid supply flow, so that the safety valve detection system provides the safety valve with a small flow, constant flow and constant pressure experimental fluid flow.

[0100] However, with the hydraulic pump as the hydraulic source, the output high-pressure liquid inevitably has fluctuations in pressure and flow. At the same time, since the power used by the booster cylinder to boost the hydraulic oil is hydraulic power, the transmission rigidity is insufficient. Therefore, when the flow demand of the hydraulic oil is extremely small, the booster cylinder is prone to creeping, causing the output flow and pressure of the booster cylinder to fluctuate, resulting in the inability of the liquid supply equipment to output high-pressure liquid with a constant flow, which in turn leads to low accuracy of the experimental results of the small flow opening, overflow and closing characteristics of the safety valve.

[0101] In order to improve the accuracy of the results of the small flow opening, overflow and closing characteristics of the safety valve measured by the safety valve detection system, an embodiment of the present invention provides a safety valve detection system. Figure 2 and Fig.11 The safety valve detection system includes the above-mentioned liquid supply device A, and the liquid supply port 220 of the liquid supply device A is connected to the liquid inlet of the safety valve.

[0102] In the case of a relatively small liquid supply flow rate, the liquid supply port of the above-mentioned liquid supply device A can output high-pressure liquid with a constant flow rate, thereby improving the accuracy of the safety valve detection system's test results on the safety valve's small flow opening, overflowing and closing characteristics.

[0103] As a possible implementation, a pressure stabilizing tank 700 is connected in series to the liquid supply pipeline 200, and the pressure stabilizing tank 700 can balance the amount of working liquid of the liquid supply device, so as to replenish the working liquid to the liquid supply device in time when the working liquid of the liquid supply device is less.

[0104] As an embodiment, the liquid supply pipeline 200 is further provided with a relief valve 800 , and the relief valve 800 is arranged in parallel with the liquid supply port 220 , so that the relief valve 800 can adjust the liquid supply pressure of the liquid supply port 220 .

[0105] Of course, the unloading valve 800 may be a manual unloading valve 820 , or an electromagnetic unloading valve 810 , or a manual unloading valve 820 and an electromagnetic unloading valve 810 connected in parallel.

[0106] In order to save resources and make the working liquid of the safety valve detection system recyclable, the above-mentioned liquid supply device also includes a liquid collecting tank 900. The liquid collecting tank 900 is arranged directly below the connection between the liquid supply port 220 and the safety valve, and the liquid collecting tank 900 is connected to the liquid tank 100. At this time, the liquid collecting tank 900 can collect the working liquid overflowing from the connection between the liquid supply port 220 and the safety valve, and transmit the working liquid to the liquid tank 100, so as to ensure the recycling of the working liquid and save energy.

[0107] At the same time, the liquid outlet of the unloading valve 800 should also be arranged directly above the liquid collecting tank 900 , so that the liquid collecting tank 900 can recycle the liquid flowing out of the unloading valve 800 .

[0108] Furthermore, the above-mentioned liquid supply equipment also includes a filter device 910, the liquid inlet of the filter device 910 is connected to the liquid collecting tank 900, and the liquid outlet of the filter device 910 is connected to the liquid tank 100, so that the filter device 910 can filter the recovered working liquid to ensure the cleanliness of the working liquid.

[0109] At the same time, the liquid supply device further includes a radiator 920, which is disposed between the liquid collecting tank 900 and the liquid tank 100. The radiator 920 can cool the recovered working liquid, reduce the working temperature of the working liquid, and further improve the accuracy of the small flow opening, overflowing and closing characteristic test results of the safety valve measured by the safety valve detection system.

[0110] Embodiment 1

[0111] The above safety valve detection system is tested.

[0112] The test method is:

[0113] Liquid supply pressure detection: the rotation speed of the motor 321 is adjusted, and the pressure sensor is used to detect the liquid supply pressure of the liquid supply port 220 at different rotation speeds of the motor 321 .

[0114] Liquid supply volume detection: Use a beaker to receive the working liquid overflowing from the liquid supply port 220, and use the beaker to measure the volume of the working liquid overflowing from the liquid supply port 220. Adjust the speed of the motor 321 at unit time intervals, and record the volume of the working liquid overflowing from the liquid supply port 220 in each unit time, calculate whether the liquid supply volume can reach 0.04min / L, and then adjust the motor speed to achieve flow adjustment and calibration.

[0115] Fluctuation value of liquid supply flow rate: control the speed of motor 321 to the speed corresponding to the liquid supply volume of 0.04min / L, detect the liquid supply volume of the liquid supply device per unit time, and calculate the fluctuation value of the liquid supply volume.

[0116] The experimental results are as follows:

[0117] The liquid supply of the liquid supply device can reach 0.04min / L, and the fluctuation value of the liquid supply is less than ±10% of the rated output liquid volume. It can be seen that the liquid supply device of the hydraulic valve detection system provided by the embodiment of the present invention can provide a small flow of high-pressure liquid, thereby ensuring the accuracy of the small flow opening, overflowing and closing characteristic test of the safety valve.

[0118] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0119] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A control method for a liquid supply device, characterized in that: The liquid supply device comprises: Liquid tank; A liquid supply pipeline, wherein the liquid supply pipeline has a liquid inlet and a liquid supply port; A loading device, the loading device comprising a plunger cylinder and a driving device; The plunger cylinder comprises a plunger cylinder barrel and a first piston rod slidably matched with the working chamber of the plunger cylinder barrel, the liquid box is connected with the working chamber of the plunger cylinder barrel through a liquid inlet pipe, and the liquid inlet of the liquid supply pipe is connected with the working chamber of the plunger cylinder barrel; The driving device comprises a motor and a transmission assembly, wherein the transmission assembly can convert the rotation of the motor into the reciprocating motion of the first piston rod, and the transmission parts in the transmission assembly are all made of rigid materials; A first valve, which is serially connected to the liquid inlet pipeline and is a one-way valve, and which only allows the liquid in the liquid inlet pipeline to flow into the working chamber of the plunger cylinder; a second valve, the second valve being serially connected to the liquid supply pipeline, the second valve being a one-way valve, and the second valve only allowing the liquid in the working chamber of the plunger cylinder to flow into the liquid supply pipeline; The liquid supply device comprises two groups of loading devices, the working chamber of the plunger cylinder in each group of loading devices is communicated with the liquid inlet pipeline through a first valve, and the working chamber of the plunger cylinder in each group of loading devices is communicated with the liquid supply pipeline through a second valve; The driving device is an electric cylinder, which includes a motor, a ball screw, an electric cylinder barrel and a second piston rod; the ball screw and the second piston rod are both located in the working chamber of the electric cylinder barrel; the ball screw includes a screw rod and a ball nut threadedly connected to the screw rod, the screw rod is coaxially fixedly connected to the output shaft of the motor, and the ball nut is slidably connected to the working chamber of the electric cylinder barrel; the first end of the second piston rod is fixedly connected to the ball nut, the second end of the second piston rod extends out of the working chamber of the electric cylinder barrel, and the second end of the second piston rod is coaxially fixedly connected to the first piston rod; The control method comprises: Preliminary step: enabling the first group of loading devices to perform a liquid aspiration operation; The liquid suction operation includes: controlling the motor to rotate in a first direction to move the first piston rod from a first position to a second position, wherein when the first piston rod is in the first position, the lower end of the first piston rod is flush with the bottom of the working chamber of the hydraulic cylinder, and when the first piston rod is in the second position, the lower end of the first piston rod is flush with the top of the working chamber of the hydraulic cylinder; A first liquid supplying step: causing the first group of loading devices to perform a liquid supplying operation, while causing the second group of loading devices to perform a liquid aspirating operation; The first liquid supply step is specifically: receiving position information of pistons in the second group of loading devices; receiving pressure information of working fluid in the working chamber of the plunger cylinder in the second group of loading devices; The motors in the first group of the loading devices are rotated in the second direction at a first speed, and the motors in the second group of the loading devices are rotated in the first direction at a second speed; wherein the first speed is greater than the second speed; When the first piston rod in the second group of loading devices moves to the second position, the second group of loading devices stops rotating, and then gradually accelerates the rotation in the second direction, so that the motor in the first group of loading devices gradually decelerates the rotation in the second direction, and the sum of the speeds of the motors in the two groups of loading devices is the first speed, until the pressure of the working fluid in the working chamber of the plunger cylinder in the second group of loading devices reaches the critical pressure of the second valve; A second liquid supplying step: causing the first group of loading devices to perform a liquid aspiration operation, while causing the second group of loading devices to perform a liquid supplying operation; Repeating step: Repeat the first liquid supplying step and the second liquid supplying step until the liquid supplying is completed.

2. The control method according to claim 1, characterized in that: The second liquid supply step is specifically as follows: Receiving a first set of position information of the loading device piston; Receiving pressure information of working fluid in the working chamber of the plunger cylinder in the first group of loading devices; The motors in the second group of loading devices are rotated at a first speed along the second direction, and the motors in the first group of loading devices are rotated at a second speed along the first direction; wherein the first speed is greater than the second speed; When the first piston rod in the first group of loading devices moves to the second position, the motor in the first group of loading devices stops rotating and then gradually accelerates in the second direction, and the motor in the second group of loading devices gradually decelerates in the second direction, and the sum of the speeds of the motors in the two groups of loading devices is made to be the first speed, until the pressure of the working fluid in the working chamber of the plunger cylinder in the first group of loading devices reaches the critical pressure of the second valve.

3. A liquid supply device, used to execute the control method according to claim 1 or 2, characterized in that: include: Liquid tank; A liquid supply pipeline, wherein the liquid supply pipeline has a liquid inlet and a liquid supply port; A loading device, the loading device comprising a plunger cylinder and a driving device; The plunger cylinder comprises a plunger cylinder barrel and a first piston rod slidably matched with the working chamber of the plunger cylinder barrel, the liquid box is connected with the working chamber of the plunger cylinder barrel through a liquid inlet pipe, and the liquid inlet of the liquid supply pipe is connected with the working chamber of the plunger cylinder barrel; The driving device is an electric cylinder, which includes a motor and a transmission assembly. The transmission assembly can convert the rotation of the motor into the reciprocating motion of the first piston rod, and the transmission parts in the transmission assembly are all made of rigid materials; A first valve, which is serially connected to the liquid inlet pipeline and is a one-way valve, and which only allows the liquid in the liquid inlet pipeline to flow into the working chamber of the plunger cylinder; a second valve, the second valve being serially connected to the liquid supply pipeline, the second valve being a one-way valve, and the second valve only allowing the liquid in the working chamber of the plunger cylinder to flow into the liquid supply pipeline; The liquid supply device comprises two groups of loading devices, the working chamber of the plunger cylinder in each group of loading devices is communicated with the liquid inlet pipeline through a first valve, and the working chamber of the plunger cylinder in each group of loading devices is communicated with the liquid supply pipeline through a second valve; The electric cylinder includes a ball screw, an electric cylinder barrel and a second piston rod; the ball screw and the second piston rod are both located in the working chamber of the electric cylinder barrel; the ball screw includes a screw and a ball nut threadedly connected to the screw, the screw is coaxially fixed to the output shaft of the motor, and the ball nut is slidably connected to the working chamber of the electric cylinder barrel; the first end of the second piston rod is fixed to the ball nut, the second end of the second piston rod extends out of the working chamber of the electric cylinder barrel, and the second end of the second piston rod is coaxially fixed to the first piston rod.

4. The liquid supply device according to claim 3, characterized in that: A first flange is fixedly connected to the plunger cylinder, and the first flange is coaxially arranged with the first piston rod; A second flange is fixedly connected to the electric cylinder, and the second flange is coaxially arranged with the second piston rod; The loading device further comprises a flange sleeve, a first end of the flange sleeve is connected to the first flange, and a second end of the flange sleeve is connected to the second flange.

5. The liquid supply device according to claim 4, characterized in that: A stop structure is provided between the first flange and the first end of the flange sleeve, and a stop structure is also provided between the second flange and the second end of the flange sleeve.

6. A hydraulic system, characterized in that: It comprises an execution device and a liquid supply device according to any one of claims 3 to 5, wherein the liquid supply port of the liquid supply device is connected to the liquid inlet of the execution device.

7. A safety valve detection system, characterized in that: The safety valve detection system comprises the liquid supply device according to any one of claims 3 to 5, wherein the liquid supply port of the liquid supply device is connected to the liquid inlet of the safety valve.

8. The safety valve detection system according to claim 7, characterized in that: The liquid supply pipeline is connected in series with a pressure stabilizing tank; and / or The liquid supply pipeline is also provided with a relief valve, and the relief valve is arranged in parallel with the liquid supply port.

9. The safety valve detection system according to claim 7, characterized in that: The liquid supply device further comprises a liquid collecting tank, which is arranged directly below the connection between the liquid supply port and the safety valve, and the liquid collecting tank is communicated with the liquid tank.

10. The safety valve detection system according to claim 9, characterized in that: The liquid supply device further comprises a filter device, the liquid inlet of the filter device is connected to the liquid collecting tank, the liquid outlet of the filter device is connected to the liquid tank, and / or, The liquid supply device further comprises a radiator, and the radiator is arranged between the liquid collecting tank and the liquid tank.

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