Liquid pressure control method for liquid pressure calibration device

Abstract

An embodiment of the present invention discloses a liquid pressure control method for a liquid pressure calibration device, wherein a first liquid circuit and a second liquid circuit with different pressure output ranges are arranged in parallel between a liquid pressure inlet and a liquid pressure output port of the liquid pressure calibration device, the pressure output range of the first liquid circuit is continuous with the pressure output range of the second liquid circuit, a target pressure to be output is compared with a switching pressure, and the first liquid circuit or the second liquid circuit is selected to supply pressure to the liquid pressure output port according to the comparison result, and the target pressure is output, thereby supplying pressure based on two liquid circuits with different pressure ranges arranged in parallel, and determining the pressure supply liquid circuit according to the output target pressure, thereby avoiding the problem of a single liquid circuit providing a full range of liquid pressure, and a large volume caused by a large piston cavity and a long screw, so as to realize the output of liquid pressure on demand within a limited volume of the liquid pressure calibration device, and improve the portability of the liquid pressure calibration device.

Description

Technical Field

[0001] The invention relates to the field of liquid pressure control, and in particular to a liquid pressure control method for a liquid pressure calibration device. Background Art

[0002] Pressure gauges, pressure transmitters, pressure switches and other pressure instruments used in industrial production, pressure measurement and other fields need to be regularly calibrated (e.g., verified and calibrated) to ensure the accuracy of the pressure detected by the pressure instruments. It is inconvenient to carry a large number of pressure instruments in industrial sites to the laboratory for calibration. One calibration method is to carry a pressure test device to the site to calibrate the pressure instruments.

[0003] The electric liquid pressure calibration device is a device used to calibrate the pressure instrument. It uses a motor as a driving source and can be used to calibrate the pressure instrument on site. The main structure of the electric liquid pressure calibration device is as follows: Figure 1 As shown, it includes a cylinder with a piston inside, the piston is connected to a lead screw, and the lead screw is connected to a motor shaft. When the electric liquid pressure calibration device is working, the motor shaft rotates to drive the lead screw to rotate, and the lead screw rotates to drive the piston to move left and right to change the pressure of the liquid in the cylinder, thereby completing the control of the output liquid pressure.

[0004] In the process of using electric liquid pressure calibration device for liquid pressure control, in the scene with higher liquid pressure demand or when calibrating high-pressure pressure instrument, in order to provide higher liquid pressure Figure 1 The electric liquid pressure calibration device shown requires a larger pressure chamber and a longer screw, and needs to be equipped with a higher-power motor, which results in the electric liquid pressure calibration device itself being larger in size, which is not conducive to movement and transportation, and can easily cause inconvenience to users in movement and transportation scenarios. Summary of the invention

[0005] An embodiment of the present invention provides a liquid pressure control method for a liquid pressure calibration device, which can output liquid pressure on demand within a limited volume of the liquid pressure calibration device, thereby improving the portability of the liquid pressure calibration device.

[0006] The embodiment of the present invention adopts the following technical solution:

[0007] A liquid pressure control method for a liquid pressure calibration device, the device comprising:

[0008] Liquid pressure inlet, used for introducing pressure liquid;

[0009] Liquid pressure output port, used for outputting pressure liquid;

[0010] a first liquid circuit having an input end and an output end, wherein the input end of the first liquid circuit is connected to the liquid pressure inlet, and the output end of the first liquid circuit is connected to the liquid pressure outlet;

[0011] a second liquid circuit having an input end and an output end and arranged in parallel with the first liquid circuit, the input end of the second liquid circuit being connected to the liquid pressure inlet, and the output end of the second liquid circuit being connected to the liquid pressure outlet;

[0012] The method comprises:

[0013] Determining the target pressure that the device needs to output;

[0014] Compare the target pressure with the pre-stored switching pressure, and selectively control the first liquid circuit or the second liquid circuit to supply pressure to the liquid pressure output port according to the comparison result; wherein the pressure output range of the first liquid circuit is continuous with the pressure output range of the second liquid circuit.

[0015] In a possible implementation, comparing the target pressure with the pre-stored switching pressure, and selectively controlling the first fluid circuit or the second fluid circuit to supply pressure to the fluid pressure output port according to the comparison result includes:

[0016] If the target pressure value is greater than the switching pressure, the first fluid circuit supplies pressure; if the target pressure value is less than or equal to the switching pressure, the second fluid circuit supplies pressure.

[0017] In a possible implementation, the method further includes:

[0018] Obtaining the current pressure of the liquid pressure output port;

[0019] The step of supplying pressure by the first fluid circuit if the target pressure value is greater than the switching pressure, and supplying pressure by the second fluid circuit if the target pressure value is less than or equal to the switching pressure includes:

[0020] If the switching pressure is between the current pressure and the target pressure, the first liquid circuit and the second liquid circuit are switched when the switching pressure is reached, and the switched liquid circuit supplies pressure to the liquid pressure output port;

[0021] If the switching pressure is not between the current pressure and the target pressure, the current fluid circuit supplies pressure to the fluid pressure output port.

[0022] In a possible implementation manner, the pressure supply starting point of the switched fluid circuit is the switching pressure.

[0023] In a possible implementation, if the switching pressure is between the current pressure and the target pressure, the first liquid circuit and the second liquid circuit are switched when the switching pressure is reached, and the switched liquid circuit supplies pressure to the liquid pressure output port, including:

[0024] If the current pressure is greater than the switching pressure, the pressure is reduced to the switching pressure by the first fluid circuit pressure supply, and then the target pressure is output by the second fluid circuit pressure supply;

[0025] If the current pressure is lower than the switching pressure, the pressure is increased to the switching pressure by the second fluid circuit supply pressure, and then the target pressure is output by the first fluid circuit supply pressure.

[0026] In a possible implementation manner, the pressure output range of the first fluid circuit and the pressure output range of the second fluid circuit are continuous at the switching pressure.

[0027] In a possible implementation, the maximum output pressure in the pressure output range of the first liquid circuit is greater than the maximum output pressure in the pressure output range of the second liquid circuit, and the minimum output pressure in the pressure output range of the first liquid circuit is greater than the minimum output pressure in the pressure output range of the second liquid circuit.

[0028] In a possible embodiment, a booster is provided on the first liquid circuit, and the booster includes a first compression chamber and a second compression chamber. The first compression chamber and the second compression chamber are constructed such that the first compression chamber and the second compression chamber are filled with liquid medium, and when the pressure of the liquid medium in the first compression chamber changes by ΔP, the pressure of the liquid medium in the second compression chamber changes by N times ΔP, where N is greater than 1.

[0029] In a possible implementation manner, the liquid medium in the first compression chamber is isolated from the liquid medium in the second compression chamber, the first compression chamber is connected to the liquid pressure inlet, and the second compression chamber is connected to the liquid pressure outlet.

[0030] In a possible implementation manner, the cross-sectional area of ​​the first compression chamber is M times the cross-sectional area of ​​the second compression chamber;

[0031] A first piston is disposed in the first compression chamber, and the pressure of the liquid in the first compression chamber is controlled by controlling the position of the first piston;

[0032] A second piston is arranged in the second compression chamber, and the pressure of the liquid in the second compression chamber is controlled by controlling the position of the second piston.

[0033] In a possible implementation, when the second liquid circuit supplies pressure to the liquid pressure output port, the second liquid circuit is communicated with the second compression chamber, so that the second liquid circuit outputs liquid to push the second piston to move to increase the volume of the second compression chamber.

[0034] In a possible implementation manner, the first piston and the second piston move synchronously.

[0035] In a possible implementation manner, the M is equal to the N.

[0036] In a possible implementation, the device further includes: an electrically driven liquid pressure source, wherein an output end of the electrically driven liquid pressure source is connected to the liquid pressure inlet;

[0037] The first fluid circuit and the second fluid circuit share the electrically driven fluid pressure source.

[0038] In a possible implementation manner, the liquid pressure output by the first liquid circuit is greater than the liquid pressure output by the output end of the electrically driven liquid pressure source;

[0039] The liquid pressure output by the second liquid circuit is less than or equal to the liquid pressure output by the output end of the electrically driven liquid pressure source.

[0040] The above technical solution provides a liquid pressure control method for a liquid pressure calibration device, in which a first liquid circuit and a second liquid circuit with different pressure output ranges are arranged in parallel between a liquid pressure inlet and a liquid pressure output port of the liquid pressure calibration device, the pressure output range of the first liquid circuit is continuous with the pressure output range of the second liquid circuit, the target pressure to be output is compared with the switching pressure, and the first liquid circuit or the second liquid circuit is selected as the liquid pressure output port for supplying pressure to output the target pressure according to the comparison result, thereby supplying pressure based on two liquid circuits with different pressure ranges arranged in parallel, determining the pressure supply liquid circuit according to the output target pressure, avoiding the problem of a large volume caused by a large piston cavity and a long lead screw providing a full range of liquid pressure by a single liquid circuit, and realizing the output of liquid pressure on demand within the limited volume of the liquid pressure calibration device, thereby improving the portability of the liquid pressure calibration device.

[0041] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0043] Figure 1 It is a structural schematic diagram of an existing liquid pressure calibration device;

[0044] Figure 2 One of the structural schematic diagrams of the liquid pressure calibration device provided in an embodiment of the present invention;

[0045] Figure 3 A second structural schematic diagram of a liquid pressure calibration device provided in an embodiment of the present invention;

[0046] Figure 4 A third structural schematic diagram of a liquid pressure calibration device provided in an embodiment of the present invention;

[0047] Figure 5 A schematic diagram of the structure of a pressure booster in a liquid pressure calibration device provided in an embodiment of the present invention;

[0048] Figure 6 A fourth structural schematic diagram of a liquid pressure calibration device provided in an embodiment of the present invention;

[0049] Figure 7 A fifth structural diagram of a liquid pressure calibration device provided in an embodiment of the present invention;

[0050] Figure 8 A sixth structural diagram of a liquid pressure calibration device provided in an embodiment of the present invention;

[0051] Fig. 9 One of the structural schematic diagrams of the electrically driven liquid pressure source provided by an embodiment of the present invention;

[0052] Fig.10 The second structural schematic diagram of the electrically driven liquid pressure source provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0053] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0054] The "first" mentioned in the embodiments of the present application is only used as a name identifier and does not mean the first in order, and the same rule applies to "second" etc. Unless otherwise specified, "first" and "second" in this article refer to different things, for example, the first liquid circuit and the second liquid circuit are different liquid circuits.

[0055] In the embodiment of the present invention, the pressure instrument may be an instrument with a pressure measurement function, such as a pressure gauge, a pressure transmitter, or a pressure switch.

[0056] An embodiment of the present invention provides a liquid pressure calibration device, which can be used for calibrating the pressure instrument. The calibration process is as follows: the pressure instrument to be calibrated and a standard meter with higher accuracy are connected to the liquid pressure calibration device, and the liquid pressure calibration device simultaneously supplies pressure to the pressure instrument to be calibrated and the standard meter to ensure that the pressure instrument to be calibrated and the standard meter measure the same pressure, and compares the measured value of the pressure instrument to be calibrated with the measured value of the standard meter, so as to determine whether the accuracy of the pressure instrument to be calibrated meets the requirements.

[0057] like Figure 2 As shown, the liquid pressure calibration device of the embodiment of the present invention comprises:

[0058] A liquid pressure inlet A is used to introduce pressure liquid, and a liquid pressure output port B is used to output pressure liquid; a first liquid circuit 200 having an input end and an output end, the input end of the first liquid circuit 200 is connected to the liquid pressure inlet, and the output end of the first liquid circuit 200 is connected to the liquid pressure output port; a second liquid circuit 300 having an input end and an output end arranged in parallel with the first liquid circuit 200, the input end of the second liquid circuit 300 is connected to the liquid pressure inlet, and the output end of the second liquid circuit 300 is connected to the liquid pressure output port.

[0059] Among them, when the liquid pressure calibration device has a built-in pressure source such as a liquid pressure pump, the liquid pressure inlet is connected to the liquid output pipeline of the pressure source; when the liquid pressure calibration device has an external pressure source such as a liquid pressure pump, the liquid pressure inlet can be set on the housing of the liquid pressure calibration device for an external pressure source. The liquid pressure output port outputs liquid pressure for pressure calibration of the object to be calibrated. The first liquid circuit 200 and the second liquid circuit 300 are arranged in parallel, and after the liquid pressure is introduced from the liquid pressure inlet, it is divided into two paths, namely the first liquid circuit 200 and the second liquid circuit 300. The first liquid circuit 200 and the second liquid circuit 300 are controlled and finally output from the liquid pressure output port. At the same time, one of the first liquid circuit 200 and the second liquid circuit 300 outputs liquid pressure to the liquid pressure output port for use in calibrating the pressure instrument.

[0060] The pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 are continuous and at least partially non-overlapping, and some pressure points in the pressure output range of the first liquid circuit 200 overlap with some pressure points in the pressure output range of the second liquid circuit 300.

[0061] The embodiment of the present invention further provides a liquid pressure control method for the above-mentioned liquid pressure calibration device. The liquid pressure control method can be implemented by a module with a control function such as a processing module, a controller, and a processor provided in the above-mentioned liquid pressure calibration device. The liquid pressure control method includes:

[0062] Determine the target pressure that the device needs to output, compare the target pressure with the pre-stored switching pressure, and selectively control the first liquid circuit 200 or the second liquid circuit 300 to supply pressure to the liquid pressure output port according to the comparison result; wherein the pressure output range of the first liquid circuit 200 is continuous with the pressure output range of the second liquid circuit 300.

[0063] Among them, according to different application scenarios, the target pressure can be determined according to user input, and the target pressure can also be determined according to the instrument being calibrated. The embodiment of the present invention does not limit the method of determining the target pressure.

[0064] For example, the target pressure input by the user is received by setting a keyboard or a touch screen input box in the liquid pressure calibration device. Specifically, a pressure output task is received, and the pressure output task includes multiple pressure points to be output, and each pressure point to be output can be implemented by referring to the control method of the target pressure point.

[0065] For another example, when the target pressure is determined according to the instrument to be calibrated, if the pressure instrument to be calibrated needs to be calibrated at multiple different pressure points, the pressure control method of each pressure point can be implemented by referring to the control method of the target pressure point.

[0066] The first liquid circuit 200 and the second liquid circuit 300 are switched at the switching pressure. According to the pressure output requirement, the specific switching mode can be that the first liquid circuit 200 is switched to the second liquid circuit 300 or that the second liquid circuit 300 is switched to the first liquid circuit 200. The connecting pressure point of the pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 is the switching pressure. Except for the switching pressure, the pressure point included in the pressure output range of the first liquid circuit 200 is greater than the pressure point included in the pressure output range of the second liquid circuit 300. The maximum output pressure in the pressure output range of the first liquid circuit 200 is greater than the maximum output pressure in the pressure output range of the second liquid circuit 300; the minimum output pressure in the pressure output range of the first liquid circuit 200 is greater than the minimum output pressure in the pressure output range of the second liquid circuit 300.

[0067] Wherein, both the first liquid circuit 200 and the second liquid circuit 300 can output the switching pressure, the maximum output pressure in the pressure output range of the second liquid circuit 300 is the switching pressure, and the minimum output pressure in the pressure output range of the first liquid circuit 200 is the switching pressure. All output points except the switching pressure in the pressure output range of the first liquid circuit 200 are greater than the pressure output points in the second pressure range. The upper limit of the pressure output range of the second liquid circuit is the switching pressure, and the lower limit of the pressure output range of the first liquid circuit 200 is the switching pressure.

[0068] In an optional embodiment, comparing the target pressure with the pre-stored switching pressure, and selectively controlling the first liquid circuit 200 or the second liquid circuit 300 to supply pressure to the liquid pressure output port according to the comparison result includes:

[0069] If the target pressure value is greater than the switching pressure, the first fluid circuit 200 supplies pressure, and if the target pressure value is less than or equal to the switching pressure, the second fluid circuit 300 supplies pressure.

[0070] Wherein, both the first liquid circuit 200 and the second liquid circuit 300 can output the switching pressure. When the target pressure is equal to the switching pressure, according to the specific application scenario, the switching pressure can be output by the first liquid circuit 200 or by the second liquid circuit. Specifically, when the calibrated pressure instrument needs to calibrate multiple pressure points, if one of the pressure points is the switching pressure, the first liquid circuit 200 can be set to output the switching pressure when the subsequent pressure point is greater than the switching pressure; when the pressure point that the calibrated pressure instrument needs to calibrate is the switching pressure, the second liquid circuit 300 outputs the switching pressure.

[0071] In an optional embodiment, the liquid pressure control method further includes:

[0072] The current pressure of the liquid pressure output port is obtained; further, if the target pressure value is greater than the switching pressure, the first liquid circuit 200 supplies the pressure, and if the target pressure value is less than or equal to the switching pressure, the second liquid circuit 300 supplies the pressure, including:

[0073] If the switching pressure is between the current pressure and the target pressure, the first liquid circuit 200 and the second liquid circuit 300 are switched when the switching pressure is reached, and the switched liquid circuit supplies pressure to the liquid pressure output port; if the switching pressure is not between the current pressure and the target pressure, the current liquid circuit supplies pressure to the liquid pressure output port.

[0074] The liquid pressure calibration device provided in the embodiment of the present invention may be provided with a pressure sensor at the liquid pressure output port for detecting the current pressure of the liquid pressure output port. The switching pressure may be pre-stored in the liquid pressure calibration device.

[0075] The switching pressure is between the current pressure and the target pressure, that is, the current pressure is less than the switching pressure and the switching pressure is less than the target pressure, or the current pressure is greater than the switching pressure and the switching pressure is greater than the target pressure.

[0076] In an optional embodiment, the starting point of the pressure supply of the switched liquid circuit is the switching pressure. After the switching pressure is switched between the first liquid circuit 200 and the second liquid circuit 300, the switched liquid circuit continues to supply pressure with the switching pressure as the starting point of the pressure supply. Specifically, if in the process of boosting pressure, the output pressure of the second liquid circuit 300 is boosted to the switching pressure, and the second liquid circuit 300 is switched to the first liquid circuit 200, and the first liquid circuit 200 continues to boost pressure with the switching pressure as the starting point; if in the process of reducing pressure, the output pressure of the first liquid circuit 200 is reduced to the switching pressure, and the first liquid circuit 200 is switched to the second liquid circuit 300, and the second liquid circuit 300 continues to reduce pressure with the switching pressure as the starting point.

[0077] In an optional embodiment, if the switching pressure is between the current pressure and the target pressure, the first liquid circuit 200 and the second liquid circuit 300 are switched when the switching pressure is reached, and the switched liquid circuit supplies pressure to the liquid pressure output port, including:

[0078] If the current pressure is greater than the switching pressure, the pressure is reduced to the switching pressure by the first liquid circuit 200, and then the pressure is switched to the target pressure by the second liquid circuit 300; if the current pressure is less than the switching pressure, the pressure is increased to the switching pressure by the second liquid circuit 300, and then the pressure is switched to the target pressure by the first liquid circuit 200.

[0079] Specifically, if the current pressure is greater than the switching pressure, the current pressure supply liquid circuit is the first liquid circuit 200. After the pressure is reduced to the switching pressure by the first liquid circuit 200, the pressure is switched to the second liquid circuit 300 to output the target pressure. The second liquid circuit 300 starts to reduce the pressure from the switching pressure until the target pressure is reached. If the current pressure is less than the switching pressure, the current pressure supply liquid circuit is the second liquid circuit 300. After the pressure is increased to the switching pressure by the second liquid circuit 300, the pressure is switched to the first liquid circuit 200 to output the target pressure. The first liquid circuit 200 starts to increase the pressure from the switching pressure until the target pressure is reached.

[0080] In an optional embodiment, the pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 are continuous at the switching pressure. That is, the point where the pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 overlap is the switching pressure, and since the first liquid circuit 200 and the second liquid circuit 300 are switched at the switching pressure, the output liquid pressure is continuous when the first liquid circuit 200 and the second liquid circuit 300 are switched.

[0081] In an optional embodiment, the maximum output pressure in the pressure output range of the first liquid circuit 200 is greater than the maximum output pressure in the pressure output range of the second liquid circuit 300, and the minimum output pressure in the pressure output range of the first liquid circuit 200 is greater than the minimum output pressure in the pressure output range of the second liquid circuit 300. Specifically, the overlap point of the pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 is located at the switching pressure, and except for the switching pressure, the pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 do not overlap, and the pressure output range of the first liquid circuit 200 and the pressure output range of the second liquid circuit 300 are continuous, so that the pressure range output by the liquid pressure calibration device is wider and the maximum output pressure is higher, so that more pressure instruments with different ranges can be calibrated.

[0082] In an optional embodiment, a booster is provided on the first liquid circuit 200, and the booster includes a first compression chamber and a second compression chamber. The first compression chamber and the second compression chamber are constructed such that the first compression chamber and the second compression chamber are filled with liquid medium, and when the pressure of the liquid medium in the first compression chamber changes by △P, the pressure of the liquid medium in the second compression chamber changes by N times △P, and N is greater than 1.

[0083] Those skilled in the art should understand that when N is greater than 1, the second compression chamber in the supercharger can achieve pressurization, and as N increases, the greater the liquid pressurization amplitude in the second compression chamber, the higher the maximum liquid pressure output. However, the larger the value of N, the greater the energy required to pressurize the liquid in the first compression chamber, and the higher the performance requirements for the first compression chamber pressure supply device (such as a liquid pressure pump). For example, in one example, 3≤N≤8, in another example, 5≤N≤12, and in yet another example, 10≤N≤15. It should be understood that the above-mentioned value range of N is only exemplary. The value range of N can be determined as needed, taking into account the maximum liquid pressure output demand and the performance of the liquid pressure supply source (such as a liquid pressure pump) to determine an appropriate value.

[0084] In an optional embodiment, the liquid medium in the first compression chamber is isolated from the liquid medium in the second compression chamber, the first compression chamber is connected to the liquid pressure inlet, and the second compression chamber is connected to the liquid pressure outlet.

[0085] In an optional embodiment, the cross-sectional area of ​​the first compression chamber is M times the cross-sectional area of ​​the second compression chamber, where M is greater than 1; a first piston is disposed in the cavity body of the first compression chamber; a second piston is disposed in the second compression chamber, and the first piston is linked to the second piston, and the pressure of the liquid in the second compression chamber is controlled by controlling the position of the second piston.

[0086] Furthermore, in an optional embodiment, the first piston and the second piston move synchronously, the first piston in the first compression chamber moves to increase the volume of the first compression chamber, and a second piston is arranged in the second compression chamber to move synchronously with the movement of the first piston, so that the volume of the second compression chamber is reduced, thereby compressing the liquid in the second compression chamber.

[0087] The liquid in the first compression chamber is pressurized so that the liquid in the second compression chamber increases N times as the pressure of the liquid in the first compression chamber increases. Specifically, the liquid in the first compression chamber is pressurized, and the volume of the first compression chamber increases to push the first piston to move.

[0088] The contact area between the first piston and the liquid medium is M times the contact area between the second piston and the liquid medium, and M is equal to N. The method for determining M can refer to the method for determining N, which is not repeated here.

[0089] In an optional embodiment, when the first liquid circuit 200 supplies pressure to the liquid pressure output port, the first liquid circuit 200 is connected to the second compression chamber, so that the first liquid circuit 200 outputs liquid to push the second piston to move to increase the volume of the second compression chamber.

[0090] Specifically, when the second liquid circuit 300 is pressurized, the pressure of the liquid in the second compression chamber is equal to the pressure of the liquid in the first liquid circuit 200, so that when the pressure of the liquid in the second liquid circuit 300 is increased to the switching pressure and the second liquid circuit 300 is switched to the first liquid circuit 200, the first liquid circuit 200 starts to increase the pressure from the switching pressure. In addition, the first liquid circuit 200 is connected with the second compression chamber, so that the output liquid in the first liquid circuit 200 during the pressurization process pushes the second piston to move, increasing the volume of the second compression chamber, so that the volume of the second compression chamber is increased before switching to the first liquid circuit 200, which is convenient for compressing the liquid in the second compression chamber after switching to the first liquid circuit 200, and achieving a greater degree of pressurization. It should be understood that preferably, when the second liquid circuit 300 is switched with the first liquid circuit 200 or before the switching, the volume of the second compression chamber is maximum or close to maximum.

[0091] In an optional embodiment, the liquid pressure calibration device further includes: an electrically driven liquid pressure source, the output end of the electrically driven liquid pressure source being connected to the liquid pressure inlet; the first liquid circuit 200 and the second liquid circuit 300 share the electrically driven liquid pressure source, and at the same time the electrically driven liquid pressure source only provides a liquid pressure source for one of the first liquid circuit 200 and the second liquid circuit 300.

[0092] In this way, the first liquid circuit 200 and the second liquid circuit 300 share the electrically driven liquid pressure source, which saves the internal space of the liquid pressure calibration device occupied by the repeatedly configured electrically driven liquid pressure source and reduces the volume of the liquid pressure calibration device.

[0093] In an optional embodiment, the liquid pressure output by the first liquid circuit 200 is greater than the liquid pressure output by the output end of the electrically driven liquid pressure source; the liquid pressure output by the second liquid circuit 300 is less than or equal to the liquid pressure output by the output end of the electrically driven liquid pressure source.

[0094] Specifically, the second liquid circuit 300 is not provided with a pressurizing device, and the pressure liquid output by the electrically driven liquid pressure source is not pressurized during the process of supplying pressure to the liquid pressure output port through the second liquid circuit 300, that is, when the second liquid circuit 300 supplies pressure to the liquid pressure output port, the liquid pressure at the liquid pressure output port is slightly less than or equal to the liquid pressure output by the electrically driven liquid pressure source; the first liquid circuit 200 is provided with a pressurizing device, and the pressure liquid output by the electrically driven liquid pressure source is pressurized during the process of supplying pressure to the liquid pressure output port through the second liquid circuit 300, so that when the first liquid circuit 200 supplies pressure to the liquid pressure output port, the liquid pressure at the liquid pressure output port is greater than the liquid pressure output by the electrically driven liquid pressure source, thereby achieving double pressurization. The first liquid circuit 200 is provided with a pressurizer to achieve the above-mentioned purpose of pressurization. The specific structure and pressurization method of the pressurizer refer to the above-mentioned related content, which will not be repeated here.

[0095] In an optional embodiment, comparing the target pressure with the pre-stored switching pressure, and selectively controlling the first liquid circuit 200 or the second liquid circuit 300 to supply pressure to the liquid pressure output port according to the comparison result includes:

[0096] When the target pressure value is greater than the switching pressure, the first fluid circuit 200 supplies pressure;

[0097] When the target pressure value is less than or equal to the switching pressure, the second fluid circuit 300 supplies pressure.

[0098] In an optional embodiment, the switching pressure is the pressure at which the first liquid circuit 200 and the second liquid circuit 300 are switched; when the target pressure value is greater than the switching pressure, the pressure supplied by the first liquid circuit 200 includes:

[0099] Obtaining the current pressure of the liquid pressure output port;

[0100] If the current pressure is lower than the switching pressure, the pressure is increased to the switching pressure by the second fluid circuit 300 , and then the pressure is switched to the first fluid circuit 200 to output the target pressure;

[0101] If the current pressure is greater than or equal to the switching pressure, the first fluid circuit 200 supplies pressure to output the target pressure.

[0102] In an optional embodiment, after switching to the first fluid circuit 200 supplying pressure to output the target pressure, the first fluid circuit 200 continues to pressurize from the pressure switching value to the target pressure.

[0103] In an optional embodiment, the switching pressure is the pressure at which the first liquid circuit 200 and the second liquid circuit 300 are switched;

[0104] When the target pressure value is less than or equal to the switching pressure, the second fluid circuit 300 supplies pressure including:

[0105] Obtaining the current pressure of the liquid pressure output port;

[0106] If the current pressure is greater than the switching pressure, the pressure is reduced to the switching pressure by the first fluid circuit 200, and then the pressure is switched to the second fluid circuit 300 to output the target pressure;

[0107] If the current pressure is less than or equal to the switching pressure, the first fluid circuit 200 supplies pressure to output the target pressure.

[0108] In an optional embodiment, after the pressure supply from the second fluid circuit 300 is switched to output the target pressure, the second fluid circuit 300 continues to reduce the pressure from the pressure switching value to the target pressure.

[0109] The liquid pressure calibration device and the liquid pressure control method for the liquid pressure calibration device provided in the present embodiment are as follows: a first liquid circuit 200 and a second liquid circuit 300 with different pressure output ranges are arranged in parallel between the liquid pressure inlet and the liquid pressure output port of the liquid pressure calibration device; the pressure output range of the first liquid circuit 200 is continuous with the pressure output range of the second liquid circuit 300; the target pressure to be output is compared with the switching pressure; the first liquid circuit 200 or the second liquid circuit 300 is selected as the liquid pressure output port to supply pressure and output the target pressure according to the comparison result; thereby, pressure is supplied based on two parallel liquid circuits with different pressure ranges; the pressure supply liquid circuit is determined according to the output target pressure; thereby, a single liquid circuit is avoided from providing a full range of liquid pressure; and the problem of a large volume caused by a large piston cavity and a long screw is avoided; thereby, the liquid pressure can be output on demand within the limited volume of the liquid pressure calibration device, thereby improving the portability of the liquid pressure calibration device.

[0110] The liquid pressure control method of the embodiment of the present invention can greatly reduce the weight and volume of the high-pressure liquid pressure calibration device, better meet the requirements of the high-pressure liquid pressure control device in terms of lightweight and miniaturization, and make the portability of the high-pressure liquid pressure control device possible.

[0111] Based on the above-mentioned liquid pressure testing device and liquid pressure control method, an embodiment of the present invention provides a specific structure of a liquid pressure testing device and a liquid pressure control method for the liquid pressure testing device.

[0112] like Figure 3As shown, the liquid pressure testing device provided in this embodiment includes a hydraulic source part 100, which is used to provide a liquid pressure source; a first liquid circuit 200, which is used to supply a high-pressure liquid greater than or equal to the switching pressure; a second liquid circuit 300, which is used to provide a low-pressure liquid less than or equal to the switching pressure; and a hydraulic lead-out part 400, which is used to output the pressure liquid.

[0113] Specifically, Figure 4 As shown, the hydraulic source part 100 includes a liquid medium tank 1, an electrically driven liquid pressure source 2 and a pressure source sensor 3; the second liquid circuit 300 includes a control valve 12, a control valve 11, a liquid medium tank 1, a low pressure sensor 10 and an isolation valve 9; the first liquid circuit 200 includes a control valve 4, a control valve 5, a liquid medium tank 1 and a booster 6; the hydraulic lead-out part 400 includes a pressure standard 7 and a liquid pressure output port 8.

[0114] like Figure 4 As shown, the liquid medium in the liquid medium box 1 is divided into two paths after passing through the electrically driven liquid pressure source 2 and the pressure source sensor 3, namely the first liquid path 200 and the second liquid path 300, wherein the first liquid path 200 passes through the control valve 4, the control valve 5, the liquid medium box 1 and the booster 6; the second liquid path 300 passes through the control valve 12, the control valve 11, the liquid medium box 1, the low pressure sensor 10 and the isolation valve 9, and then the two paths are merged and pass through the pressure standard 7 and the liquid pressure output port 8.

[0115] Specifically, the first liquid circuit 200 is provided with a control valve 4 and a control valve 5. The control valve 4 controls the on-off of the electrically driven liquid pressure source 2 and the first liquid circuit 200 (booster), thereby controlling the on-off of the electrically driven liquid pressure source 2 and the first liquid circuit 200; the control valve 5 controls the on-off of the first liquid circuit 200 and the liquid medium tank, thereby realizing the suction of liquid from the liquid medium tank 1 and the discharge of liquid to the liquid medium tank 1; the control valve and the control valve are arranged between the electrically driven liquid pressure source 2 and the booster 6 on the first liquid circuit 200. The control valve 5 is arranged between the control valve 4 and the booster 6.

[0116] During the pressurization process of the first liquid circuit 200, the control valve 4 opens the pressure liquid output by the electrically driven liquid pressure source 2 and inputs it into the first compression chamber of the booster 6, so that the volume of the first compression chamber expands and compresses the liquid in the second compression chamber to pressurize the liquid in the second compression chamber.

[0117] During the pressure reduction process of the first liquid circuit 200 , the control valve 5 is opened, and the liquid in the first compression chamber is discharged to the liquid medium tank 1 through the control valve 5 .

[0118] The second liquid circuit 300 is provided with a control valve 12, a control valve 11, and an isolation valve 9. The control valve 12 controls the connection and disconnection between the electrically driven liquid pressure source 2 and the second liquid circuit 300; the control valve 11 controls the connection and disconnection between the second liquid circuit 300 and the liquid medium box, so as to realize the suction of liquid from the liquid medium box and the discharge of liquid to the liquid medium box; the isolation valve 9 controls the connection and disconnection between the second liquid circuit 300 and the liquid pressure output port. The control valve 11 is provided between the control valve 12 and the isolation valve 9, and the control valve 12 is close to the side of the electrically driven liquid pressure source 2. During the pressurization process of the second liquid circuit 300, the control valve 12 and the isolation valve 9 are opened, and the pressure liquid output by the electrically driven liquid pressure source 2 is supplied to the liquid pressure output port. During the depressurization of the second liquid circuit 300, the control valve 11 and the isolation valve 9 are opened, and the liquid in the second liquid circuit 300 is discharged to the liquid medium tank through the control valve 11. The control valve 12 is a solenoid valve, the control valve 11 is a solenoid valve, and the isolation valve 9 is an electric isolation valve.

[0119] based on Figure 4 The liquid pressure testing device is shown, and the liquid pressure control method used in the liquid pressure testing device is described below.

[0120] When the target pressure to be output is within the pressure output range of the second fluid circuit 300, the pressure control method of the second fluid circuit 300 is as follows:

[0121] The electrically driven liquid pressure source 2 works, the pressure source sensor 3 measures the pressure value at the output end of the electrically driven liquid pressure source 2, the control valve 4 is closed, the control valve 5 is opened, the isolation valve 9 is opened, the first liquid circuit 200 is closed, and the pressure is supplied by the second liquid circuit 300. During the pressure supply of the second liquid circuit 300, the control valve 12 and the control valve 11 cooperate with each other to start the pressure control action according to the measurement value of the pressure standard 7. When the measurement value of the pressure standard 7 is lower than the target pressure value, the opening of the control valve 12 increases, and the opening of the control valve 11 decreases, and the pressure at the liquid pressure output port 8 gradually increases to approach the target pressure; when the measurement value returned by the pressure standard 7 is higher than the target pressure value, the opening of the control valve 12 decreases, and the opening of the control valve 11 increases, and the pressure at the liquid pressure output port 8 gradually decreases to approach the target pressure. Among them, the target pressure is the pressure that the liquid pressure testing device needs to output to the liquid pressure output port 8. Usually, the target pressure is input by the user or determined according to the pressure instrument to be calibrated.

[0122] When the target pressure to be output is within the pressure output range of the first fluid circuit 200, the pressure control method of the first fluid circuit 200 is as follows:

[0123] The control valve 12 is closed, the isolation valve 9 is closed, the control valve 4 is opened and the control valve 5 is opened through the booster 6, and the pressure control action is started in coordination with the measured value of the pressure standard 7. When the measured value of the pressure standard 7 is lower than the target pressure value, the opening of the control valve 4 increases, and the opening of the control valve 5 decreases, and the liquid pressure at the liquid pressure output port 8 gradually increases to approach the target pressure; when the measured value returned by the pressure standard 7 is higher than the target pressure value, the opening of the control valve 4 decreases, and the opening of the control valve 5 increases, and the liquid pressure at the liquid pressure output port 8 gradually decreases to approach the target pressure.

[0124] The above describes a method for controlling the pressure and outputting the target pressure value when the target pressure is within the pressure output range of the first fluid circuit 200 and the target pressure is within the pressure output range of the second fluid circuit 300 .

[0125] The following takes a typical application scenario as an example. The scenario is divided into a pressurization process and a pressure reduction process. The pressurization process and the pressure reduction process span the switching value, and the pressurization process and the pressure reduction process are implemented by the cooperation of the first liquid circuit 200 and the second liquid circuit 300. Multiple pressure calibration points are set for the pressurization process and the pressure reduction process.

[0126] The following introduces a method for achieving pressurization by cooperating with the first liquid circuit 200. This pressurization method is usually used in application scenarios where the pressure instrument being calibrated needs to calibrate multiple pressure points, some of the multiple pressure points are located within the pressure output range of the second liquid circuit 300 and some are located within the pressure output range of the first liquid circuit 200.

[0127] The pressure control process of the second fluid circuit 300 (upward stroke (pressure increase) low pressure section) during the pressurization process:

[0128] The electrically driven liquid pressure source 2 works, the pressure source sensor 3 measures the pressure value at the output end of the electrically driven liquid pressure source 2, the control valve 4 is closed, the control valve 5 is opened, the isolation valve 9 is opened, the first liquid circuit 200 is closed, and the pressure is supplied by the second liquid circuit 300. During the pressurization process of the second liquid circuit 300, the control valve 12 and the control valve 11 cooperate with each other according to the measured value of the pressure standard 7 to start the pressure control action, the opening of the control valve 12 increases, and the opening of the control valve 11 decreases at the same time, the system pressure will gradually increase, and the output liquid pressure will be successively from low to high until it reaches the pressure switching value, completing the pressure control of the second liquid circuit 300 (upward stroke (pressure increase) low pressure section). Among them, if the pressure instrument to be calibrated connected during the pressure supply process of the second liquid circuit 300 has a pressure point that needs to be calibrated, when the pressure point is reached, the liquid in the second liquid circuit 300 controls the pressure output so that the liquid pressure output port 8 stabilizes at the pressure point. When the pressure point inspection is completed, the second liquid circuit 300 continues to increase the pressure, and the pressure control of each pressure point within the pressure supply range of the second liquid circuit 300 is completed according to this control method until the pressure switching value is reached.

[0129] The pressure control process of the first fluid circuit 200 (upward stroke (pressure increase) high pressure section) during the pressurization process:

[0130] When the liquid pressure at the liquid pressure output port 8 reaches the pressure switching value, the second liquid circuit 300 is switched to the first liquid circuit 200, and the first liquid circuit 200 continues to be pressurized. After switching to the first liquid circuit 200, the booster 6 is started.

[0131] Specifically, after the second liquid circuit 300 supplies pressure to the switching pressure, the isolation valve 9 is closed, the control valve 4 is opened, and the pressure supply of the second liquid circuit 300 is switched to the pressure supply of the first liquid circuit 200. During the pressure control process of the first liquid circuit 200 (upward stroke (pressure increase) high pressure section): the control valve 4 and the control valve 5 start the pressure control action through the booster 6 according to the measured value of the pressure standard 7, the opening of the control valve 4 increases, and the opening of the control valve 5 decreases, and the output liquid pressure gradually increases. The pressure control of the first liquid circuit 200 (upward stroke (pressure increase) high pressure section) is completed. Among them, if the pressure instrument to be calibrated connected during the pressure supply process of the first liquid circuit 200 has a pressure point that needs to be calibrated, then when the pressure point is reached according to the above control method, the liquid control pressure output of the first liquid circuit 200 makes the liquid pressure output port 8 stable at the pressure point. After the pressure point inspection is completed, the first liquid circuit 200 continues to increase the pressure. According to this control method, the pressure control of each pressure point within the pressure supply range of the first liquid circuit 200 is completed until the maximum output pressure of the first liquid circuit 200 is reached.

[0132] The above describes the implementation method of pressurizing the second liquid circuit 300 in cooperation with the first liquid circuit 200, and increasing the pressure from the second liquid circuit 300 to the first liquid circuit 200 during the pressurization process. The following describes the implementation method of reducing the pressure from the first liquid circuit 200 to the second liquid circuit 300, and cooperating with the first liquid circuit 200 during the pressure reduction process.

[0133] During the pressure reduction process, the pressure control process of the first liquid circuit 200 (downstroke (pressure reduction) high pressure section): the control valve 4 and the control valve 5 start the pressure control action by cooperating with each other through the booster 6 according to the measured value of the pressure standard 7, the opening of the control valve 4 decreases, and the opening of the control valve 5 increases, and the pressure gradually decreases from high to low until the switching value is reached. After reaching the switching value, the isolation valve 9 opens, the control valve 4 closes, and the first circuit is switched to the second liquid circuit 300.

[0134] During the pressure reduction process, the pressure control process of the second liquid circuit 300 (low-pressure section of the downstroke (pressure reduction)): the control valve 12 and the control valve 11 cooperate with each other to start the pressure control action according to the measurement value of the pressure standard 7, the opening of the control valve 12 decreases, and the opening of the control valve 11 increases. The system pressure will gradually decrease and approach the target pressure), and the pressure control of the remaining pressure points in the downstroke (low-pressure section) is completed from high to low until the pressure reaches the lower pressure limit of the second liquid circuit 300.

[0135] The present invention provides a supercharger 6 having a structure as follows: Figure 5 As shown, the supercharger 6 comprises a low-pressure cylinder 61 and a high-pressure cylinder 62, wherein a first compression chamber 611 is provided in the low-pressure cylinder 61, and a second compression chamber 621 is provided in the high-pressure cylinder 62. The first compression chamber 611 and the second compression chamber 621 are configured such that the volume of the first compression chamber 611 increases when the first compression chamber 611 is filled with liquid, and as the volume of the first compression chamber 611 increases, the volume of the second compression chamber 621 decreases, and the liquid in the second compression chamber 621 is compressed to achieve pressurization.

[0136] Furthermore, in order to allow the pistons in the high-pressure cylinder 62 and the low-pressure cylinder 61 to slide flexibly, the embodiment of the present invention can also set the high-pressure cylinder 62 to be rotatable, and when the high-pressure cylinder 62 rotates, the second piston in the second compression chamber 621 rotates, and the first piston in the first compression chamber 611 rotates synchronously with the second piston.

[0137] The above embodiment illustrates the implementation method of calibrating multiple inspection points across the switching value and the pressure control implementation method when the target pressure is within the pressure output range of the first liquid circuit 200 or the pressure output range of the second liquid circuit 300. Those skilled in the art should understand that when the target pressure is within the pressure output range of the second liquid circuit 300, the pressure is only supplied through the first liquid circuit 200. When the target pressure is within the pressure output range of the first liquid circuit 200, if the current pressure value is within the pressure output range of the second liquid circuit 300, it is necessary to pressurize to the switching pressure through the second liquid circuit 300. After reaching the switching pressure and switching to the first liquid circuit 200, the pressure is supplied by the first liquid circuit 200.

[0138] Figure 6 A schematic diagram of the structure of a liquid pressure calibration device provided by an embodiment of the present invention, Figure 6 The liquid pressure calibration device shown includes a front housing component 6A, an internal component 6B, and a rear housing component 6C. Figure 2 , Figure 3 , Figure 4 The provided liquid pressure calibration device can be used Figure 6 The structure is constructed as described. For example, Figure 2 , Figure 3 , Figure 4 The provided liquid pressure calibration device can be integrated into Figure 6 The internal component 6B in the middle thus assembles 6A, 6B, and 6C into one body to construct a portable liquid pressure calibrator. Further, as Figure 7 As shown, a display screen 101 and an electrical signal output measurement component 102 are arranged on the upper part of the front shell component 6A; a battery 103 is arranged on the lower part of the shell component. According to different application scenarios, the display screen 101 can display parameters such as the liquid pressure value and the measured value of the calibrated pressure instrument, and an input box can be further set to receive the user to input the target pressure value. The electrical signal output measurement component 102 can be connected to the calibrated instrument to measure the electrical signal output by the calibrated instrument to determine its measured value. The battery 103 supplies power to the entire device.

[0139] In an optional embodiment, if Figure 6 , Figure 8 As shown, the rear housing assembly 6C of the liquid pressure calibrator includes a housing cover 104, a liquid medium tank 1 and a liquid tank cover 105. Figure 8 As shown, the liquid medium box 1 is attached to the housing cover 104 , and the liquid medium box 1 is buckled between the liquid box cover 105 and the liquid box cover 105 .

[0140] The liquid pressure control method for a liquid pressure calibration device provided in an embodiment of the present invention can be executed by a control module provided in the liquid pressure calibration device. The method includes the following steps:

[0141] 91. Determine the target pressure that needs to be output.

[0142] 92. Compare whether the target pressure value is greater than the pre-stored switching pressure.

[0143] 93. If the target pressure value is greater than the pre-stored switching pressure, the first fluid circuit supplies pressure.

[0144] Specifically, the current pressure of the liquid pressure output port is obtained. If the current pressure is greater than the switching pressure, the first liquid circuit is the current pressure supply liquid circuit, and the pressure continues to be supplied by the first liquid circuit; if the current pressure is less than or equal to the switching pressure, the second liquid circuit is the current pressure supply liquid circuit, and the pressure of the liquid pressure output port needs to be increased to the switching value through the second liquid circuit and then switched to the pressure supply of the first liquid circuit.

[0145] 94. If the target pressure value is less than or equal to the pre-stored switching pressure, the second fluid circuit supplies pressure.

[0146] Specifically, the current pressure of the liquid pressure output port is obtained. If the current pressure is greater than the switching pressure, the first liquid circuit is the current pressure supply liquid circuit, and the pressure of the liquid pressure output port needs to be reduced to the switching value through the first liquid circuit and then switched to the second liquid circuit pressure supply; if the current pressure is less than or equal to the switching pressure, the second liquid circuit is the current pressure supply liquid circuit, and the pressure continues to be supplied by the second liquid circuit.

[0147] like Fig. 9 , Fig.10 As shown, an embodiment of the present invention provides an electrically driven liquid pressure source 2, comprising:

[0148] The cylinder body 10A is provided with a cavity. The piston rod 20A is at least partially disposed in the cavity, and the portion of the piston rod 20A disposed in the cavity has a first end 101A and a second end 102A. Fig.10 The first end 101A is configured as a first compression chamber (high pressure cylinder) A with a variable volume. Fig. 9 The second end 102A is shown as a second compression chamber (low-pressure cylinder) B with a variable volume, and the maximum volume of the first compression chamber A is smaller than the maximum volume of the second compression chamber B. The portion of the piston rod 20A placed in the cavity is sealed with the inner wall of the cavity. Specifically, Fig. 9 , Fig.10As shown, a sealing ring C and a sealing ring D are arranged between the first compression chamber (low-pressure cylinder) A and the second compression chamber (low-pressure cylinder) B; and a sealing ring E is arranged between the second compression chamber (low-pressure cylinder) B and the outside.

[0149] The piston rod 20A reciprocates between a first position and a second position in the cavity, wherein: Fig. 9 The piston rod 20A is shown in the first position. Fig.10 The piston rod 20A is shown to be located at the second position. When the piston rod moves from the first position to the second position, the second compression chamber (low-pressure cylinder) B is compressed, and the second compression chamber (low-pressure cylinder) B is in fluid communication with the first compression chamber (high-pressure cylinder); when the piston rod moves from the second position to the first position, the first compression chamber (high-pressure cylinder) A is compressed, and the second compression chamber (low-pressure cylinder) B is fluidly blocked from the first compression chamber (high-pressure cylinder). In a possible embodiment, Fig. 9 , Fig.10 As shown, the cavity is a continuous cavity, that is, the cavity is an integrated cavity without interruption in the middle. The first compression cavity A and the second compression cavity B are both arranged in the cavity. In a possible embodiment, as Fig. 9 , Fig.10 As shown, the second end is arranged at the middle of the piston rod 20A. In a possible embodiment, as Fig. 9 , Fig.10 As shown, the second compression chamber B is annular. Specifically, the second compression chamber B is an annular cavity surrounding the axial direction of the piston rod 20A.

[0150] In one possible implementation, Fig. 9 , Fig.10 As shown, a connecting liquid path 103A is provided between the first compression chamber (high-pressure cylinder) A and the second compression chamber (low-pressure cylinder) B, and a first one-way valve 104A is provided on the connecting liquid path, and the first one-way valve 104A controls the on-off of the connecting liquid path; the first one-way valve 104A is configured to open the connecting liquid path 103A when the liquid in the second compression chamber (low-pressure cylinder) B flows to the first compression chamber (high-pressure cylinder) A. Specifically, the first one-way valve 104A is provided in the connecting liquid path 103A, blocking the liquid in the first compression chamber (low-pressure cylinder) A from flowing to the second compression chamber (high-pressure cylinder) B; and does not block the liquid in the second compression chamber (low-pressure cylinder) B from flowing to the first compression chamber (high-pressure cylinder) A. Thus, the liquid in the second compression chamber (low-pressure cylinder) B can flow to the first compression chamber (high-pressure cylinder) A in one direction.

[0151] In a possible implementation, the connecting fluid path 103A and the first one-way valve 104A are disposed in the piston rod 20A. Compared with the connecting fluid path 103A and the first one-way valve 104A being disposed outside the cylinder body 10A, the connecting fluid path 103A and the first one-way valve 104A being disposed in the piston rod 20A can reduce the volume of the electrically driven liquid pressure source 2, making it easier to achieve miniaturization.

[0152] In a possible implementation, when the piston rod 20A moves from the second position to the first position, the first compression chamber (high-pressure cylinder) A is compressed, the liquid pressure in the first compression chamber (high-pressure cylinder) A increases, and the first compression chamber (high-pressure cylinder) A outputs pressurized liquid. At the same time, the volume of the second compression chamber (low-pressure cylinder) B increases, and the second compression chamber (low-pressure cylinder) B is replenished with liquid, that is, liquid is inhaled.

[0153] In a possible embodiment, when the piston rod 20A compresses the second compression chamber (low-pressure cylinder) B during the movement from the first position to the second position, the liquid in the second compression chamber (low-pressure cylinder) B replenishes the first compression chamber (high-pressure cylinder) A.

[0154] In one possible embodiment, the cylinder body 10A is provided with an output pipeline 105A, and the output pipeline 105A is connected to the first compression chamber (high-pressure cylinder) A. A second one-way valve 106A is provided on the output pipeline 105A, and the second one-way valve 106A controls the on-off of the output pipeline 105A. The second one-way valve 106A is configured to open the output pipeline 105A when the first compression chamber (high-pressure cylinder) A outputs pressure liquid.

[0155] Specifically, the second one-way valve 106A is disposed in the output pipeline 105A to block the liquid in the output pipeline 105A from flowing to the first compression chamber (high-pressure cylinder) A, but does not block the pressure liquid in the first compression chamber (high-pressure cylinder) A from flowing to the output pipeline 105A. Thus, the liquid in the first compression chamber (low-pressure cylinder) A can flow to the output pipeline 105A in one direction.

[0156] In a possible implementation, the cylinder body 10A is provided with an overflow liquid circuit 107A, and an overflow valve 108A is provided on the overflow liquid circuit. The overflow valve 108A controls the on-off of the overflow liquid circuit 107A, and the overflow liquid circuit 107A is connected to the second compression chamber (low-pressure cylinder) B. The overflow valve 108A is configured such that when the liquid pressure in the second compression chamber (low-pressure cylinder) B is greater than the set pressure, the overflow valve 108A opens, and the liquid in the second compression chamber (low-pressure cylinder) B is discharged through the overflow liquid circuit to relieve the pressure of the second compression chamber (low-pressure cylinder) B. Specifically, the set pressure is determined according to the overflow valve 108A, and different specifications and models of the overflow valve 108A may have different pressure relief thresholds. In specific implementation, adaptation and selection may be performed according to different needs.

[0157] In a possible implementation, the cylinder body 10A is provided with a liquid suction path 109A connected to the second compression chamber (low-pressure cylinder) B, and a third one-way valve 110A is provided on the liquid suction path 109A, and the third one-way valve 110A controls the on-off of the liquid suction path 109A; the third one-way valve 110A is configured to open the liquid suction path 109A when liquid is replenished to the second compression chamber (low-pressure cylinder) A through the liquid suction path 109A. Specifically, the third one-way valve 110A is provided in the liquid suction path 109A, blocking the liquid in the second compression chamber (low-pressure cylinder) B from flowing to the liquid suction path 109A; and does not block the pressure liquid in the liquid suction path 109A from flowing to the second compression chamber (low-pressure cylinder) B. Thus, the liquid in the liquid suction path 109A can flow unidirectionally to the output pipeline 105A.

[0158] In one possible implementation, Fig. 9 , Fig.10 As shown, the electrically driven liquid pressure source 2 also includes a transmission component;

[0159] The piston rod 20A is connected to the transmission assembly, and the transmission assembly provides reciprocating power to the piston rod, so that the piston rod 20A reciprocates between a first position and a second position in the cavity.

[0160] In a possible implementation, the transmission assembly includes: a motor 111A, an eccentric shaft 112A, and a rocker arm 113A, wherein the motor rotating shaft is connected to the eccentric shaft 112A, the eccentric shaft 112A is connected to the rocker arm 113A, and the rocker arm 113A is connected to the piston rod 20A via a pin 114A.

[0161] The present invention provides a portable liquid calibration device, comprising the electrically driven liquid pressure source 2 as described above.

[0162] The working mode of the electrically driven liquid pressure source 2 according to the embodiment of the present invention is described below. Fig. 9 , Fig.10 As shown, the electrically driven liquid pressure source 2 includes: a motor 111A, an eccentric shaft 112A, and a swing rod 113A.

[0163] The eccentric shaft 112A rotates under the drive of the motor 111A, and the eccentric shaft 112A drives one end of the swing rod 113A to swing, and the other end of the swing rod 113A drives the piston rod 20A to reciprocate left and right;

[0164] When the electrically driven liquid pressure source 2 works for the first time, the first compression chamber (high-pressure cylinder) A and the second compression chamber (low-pressure cylinder) B inhale liquid, and the implementation process is as follows:

[0165] like Fig. 9 As shown, the piston rod 20A moves to the left, the liquid inside the first compression chamber (high-pressure cylinder) A is compressed, and the second compression chamber (low-pressure cylinder) B forms a negative pressure, and the external liquid is sucked into the second compression chamber (low-pressure cylinder) B through the liquid suction path 109A, and the liquid suction and the compression of the first compression chamber (high-pressure cylinder) A are completed synchronously.

[0166] The process of compression of the second compression chamber (low-pressure cylinder) B is as follows:

[0167] The piston rod 20A moves to the right, and the liquid in the second compression chamber (low-pressure cylinder) B is compressed and flows into the first compression chamber (high-pressure cylinder) A through the connecting liquid line 103A. When the pressure output by the output pipeline 105A is less than the opening threshold of the overflow valve 108A, the liquid in the second compression chamber (low-pressure cylinder) B continues to flow into the first compression chamber (high-pressure cylinder) A, and the pressure liquid in the first compression chamber (high-pressure cylinder) A flows out through the output pipeline 105A through the second one-way valve 106A to provide a liquid pressure source for subsequent components. When the pressure of the output pipeline 105A is greater than the opening threshold of the overflow valve 108A, the liquid in the second compression chamber (low-pressure cylinder) B fills the first compression chamber (high-pressure cylinder) A, and the excess liquid is discharged through the overflow valve 108A and the overflow liquid line 107A.

[0168] The process of compression of the first compression chamber (high-pressure cylinder) A is as follows:

[0169] The piston rod 20A moves to the left, and after the liquid in the first compression chamber (high-pressure cylinder) A is compressed, it is discharged through the second one-way valve 106A through the output pipeline 105A, flows out of the output one-way valve 12A and flows into the high-pressure output port 13A, and the compression process of the first compression chamber (high-pressure cylinder) A and the liquid suction process of the second compression chamber (low-pressure cylinder) B are completed synchronously. The liquid suction process of the second compression chamber (low-pressure cylinder) B is alternately performed with the compression process of the first compression chamber (high-pressure cylinder) A, so that the liquid can be sucked in from the liquid suction liquid path 109A, and the required pressure is output through the output pipeline 105A after continuous compression and pressurization.

[0170] The electrically driven liquid pressure source of the embodiment of the present invention is provided with a first compression chamber and a second compression chamber, the first compression chamber and the second compression chamber are on the same axis, and the compression directions of the first compression chamber and the second compression chamber are opposite, thereby improving the compression efficiency. A pipeline and a one-way valve are arranged inside the piston rod, and the liquid first compression chamber and the second compression chamber are connected through the pipeline in the piston rod to reduce the pressure loss and improve the pressurization efficiency. The intermediate part enters and flows to the high-pressure end. The electrically driven liquid pressure source of the embodiment of the present invention has self-priming ability. Before the liquid pressure is established, the pipeline is filled with air. The hydraulic pump can empty the pipeline air with excellent self-priming ability, so that the liquid is continuously sucked into the liquid suction port without filling the liquid. The electrically driven liquid pressure source of the embodiment of the present invention has a variable flow function. With the first compression chamber with overflow function, it has a large flow characteristic in the low pressure delivery stage and a small flow characteristic in the high pressure delivery stage; the first compression chamber and the second compression chamber work in series, and the second compression chamber is used for compression in the low pressure stage, and the smaller second compression chamber is used for compression in the high pressure stage, thereby avoiding the power consumption from increasing sharply with the increase of pressure, thereby saving power consumption. The electrically driven liquid pressure source of the embodiment of the present invention uses an automatic compensation seal mode internally, and does not rely on the viscosity of the medium to maintain the seal. The electrically driven liquid pressure source of the embodiment of the present invention can be used in a portable liquid pressure calibration device to provide a hydraulic source for the portable liquid pressure calibration device, so that the portable liquid pressure calibration device can better control the weight and volume of the device, and it is more convenient to use the portable liquid pressure calibration device to realize the on-site calibration of high-pressure liquid pressure instruments. The liquid pressure control method of the liquid pressure calibration device provided by the embodiment of the present invention is to set the first liquid circuit 200 and the second liquid circuit 300 with different pressure output ranges in parallel between the liquid pressure inlet and the liquid pressure output port of the liquid pressure calibration device, the pressure output range of the first liquid circuit 200 is continuous with the pressure output range of the second liquid circuit 300, compare the target pressure to be output with the switching pressure, and select the first liquid circuit 200 or the second liquid circuit 300 as the liquid pressure output port to output the target pressure according to the comparison result, so as to supply pressure based on the two parallel liquid circuits with different pressure ranges, determine the pressure supply liquid circuit according to the output target pressure, avoid the problem of a single liquid circuit providing a full range of liquid pressure, and the large piston cavity and the long lead screw causing a large volume, so as to realize the output of liquid pressure on demand under the limited volume of the liquid pressure calibration device, and improve the portability of the liquid pressure calibration device. According to the liquid pressure control method involved in the present invention, the high-pressure liquid pressure calibration device can be constructed as a portable device, and a battery is provided for power supply, which can meet the requirements of on-site pressure verification and calibration work.

[0171] It should be noted that any of the device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed on multiple network units. The various embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A liquid pressure control method for a liquid pressure calibration device, characterized in that: The device comprises: Liquid pressure inlet, used for introducing pressure liquid; Liquid pressure output port, used for outputting pressure liquid; a first liquid circuit having an input end and an output end, wherein the input end of the first liquid circuit is connected to the liquid pressure inlet, and the output end of the first liquid circuit is connected to the liquid pressure outlet; a second liquid circuit having an input end and an output end and arranged in parallel with the first liquid circuit, the input end of the second liquid circuit being connected to the liquid pressure inlet, and the output end of the second liquid circuit being connected to the liquid pressure outlet; The method comprises: Determining the target pressure that the device needs to output; The target pressure is compared with the pre-stored switching pressure, and the first liquid circuit or the second liquid circuit is selectively controlled to supply pressure to the liquid pressure output port according to the comparison result; wherein the pressure output range of the first liquid circuit is continuous with the pressure output range of the second liquid circuit, and the comparison result is: the target pressure is greater than the switching pressure, or the target pressure is equal to the switching pressure, or the target pressure is less than the switching pressure.

2. The method according to claim 1, characterized in that The step of comparing the target pressure with the pre-stored switching pressure and selectively controlling the first fluid path or the second fluid path to supply pressure to the fluid pressure output port according to the comparison result includes: If the target pressure value is greater than the switching pressure, the first fluid circuit supplies pressure; if the target pressure value is less than or equal to the switching pressure, the second fluid circuit supplies pressure.

3. The method according to claim 2, characterized in that The method further comprises: Obtaining the current pressure of the liquid pressure output port; The step of supplying pressure by the first fluid circuit if the target pressure value is greater than the switching pressure, and supplying pressure by the second fluid circuit if the target pressure value is less than or equal to the switching pressure includes: If the switching pressure is between the current pressure and the target pressure, the first fluid path and the second fluid path are switched when the switching pressure is reached, and the switched fluid path supplies pressure to the fluid pressure output port; If the switching pressure is not between the current pressure and the target pressure, the current fluid circuit supplies pressure to the fluid pressure output port.

4. The method according to claim 3, characterized in that The starting point of the pressure supply of the switched fluid circuit is the switching pressure.

5. The method according to claim 3 or 4, characterized in that: If the switching pressure is between the current pressure and the target pressure, the first liquid circuit and the second liquid circuit are switched when the switching pressure is reached, and the switched liquid circuit supplies pressure to the liquid pressure output port, including: If the current pressure is greater than the switching pressure, the pressure is reduced to the switching pressure by the first fluid circuit pressure supply, and then the target pressure is output by the second fluid circuit pressure supply; If the current pressure is lower than the switching pressure, the pressure is increased to the switching pressure by the second fluid circuit supply pressure, and then the target pressure is output by the first fluid circuit supply pressure.

6. The method according to any one of claims 1 to 4, characterized in that The pressure output range of the first fluid path is continuous with the pressure output range of the second fluid path at the switching pressure.

7. The method according to any one of claims 1 to 4, characterized in that The maximum output pressure in the pressure output range of the first liquid circuit is greater than the maximum output pressure in the pressure output range of the second liquid circuit, and the minimum output pressure in the pressure output range of the first liquid circuit is greater than the minimum output pressure in the pressure output range of the second liquid circuit.

8. The method according to any one of claims 1 to 4, characterized in that A booster is arranged on the first liquid circuit, and the booster includes a first compression chamber and a second compression chamber. The first compression chamber and the second compression chamber are constructed such that the first compression chamber and the second compression chamber are filled with liquid medium, and when the pressure of the liquid medium in the first compression chamber changes by ΔP, the pressure of the liquid medium in the second compression chamber changes by N times ΔP, where N is greater than 1.

9. The method according to claim 8, characterized in that The liquid medium in the first compression chamber is isolated from the liquid medium in the second compression chamber, the first compression chamber is connected to the liquid pressure inlet, and the second compression chamber is connected to the liquid pressure outlet.

10. The method according to claim 8, characterized in that The cross-sectional area of ​​the first compression chamber is M times the cross-sectional area of ​​the second compression chamber, and M is greater than 1; A first piston is disposed in the first compression chamber; A second piston is arranged in the second compression chamber, and the first piston is linked with the second piston, and the pressure of the liquid in the second compression chamber is controlled by controlling the position of the second piston.

11. The method according to claim 10, characterized in that The first piston and the second piston move synchronously. The first piston in the first compression chamber moves to increase the volume of the first compression chamber. A second piston is arranged in the second compression chamber to move synchronously with the movement of the first piston, so that the volume of the second compression chamber is reduced, thereby compressing and increasing the pressure of the liquid in the second compression chamber.

12. The method according to claim 10 or 11, characterized in that: When the second liquid circuit supplies pressure to the liquid pressure output port, the second liquid circuit is communicated with the second compression chamber, so that the second liquid circuit outputs liquid to push the second piston to move to increase the volume of the second compression chamber.

13. The method according to claim 10 or 11, characterized in that: The M is equal to the N.

14. The method according to any one of claims 1 to 4, characterized in that The device further comprises: an electrically driven liquid pressure source, wherein an output end of the electrically driven liquid pressure source is connected to the liquid pressure inlet; The first liquid circuit and the second liquid circuit share the electrically driven liquid pressure source, and at the same time, the electrically driven liquid pressure source only provides a liquid pressure source for one of the first liquid circuit and the second liquid circuit.

15. The method according to claim 14, characterized in that The liquid pressure output by the first liquid circuit is greater than the liquid pressure output by the output end of the electrically driven liquid pressure source; The liquid pressure output by the second liquid circuit is less than or equal to the liquid pressure output by the output end of the electrically driven liquid pressure source.

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