788 results about "Pressure range" patented technology

The invention relates to the technical field of state monitoring, in particular to an energy-saving air compressor running state monitoring system and method, and the system comprises a pressure slope analysis module, a deviation trend judgment module, an error fitting acquisition module, an error trend analysis module and an alarm triggering module. According to the method, a pressure range is calculated by dividing time slices, a slope ratio is generated, a dynamic threshold algorithm is combined to successively compare and capture an offset trend, frequency and current waveform data are synchronously acquired to match a timestamp to calculate a difference value, an error vector is generated in a standardized manner, and a periodic mean value is extracted to verify an incremental relationship to identify progressive anomaly. The cross validation slope ratio and error vector positioning wear or coordination abnormity, the dynamic threshold value is adjusted along with the mean value coefficient at the initial period to reduce fluctuation interference, the timestamp matching enhances the composite fault detection capability, and the range division operation quantifies the matching degree to provide an energy efficiency optimization basis. And a standardized error vector and mean value incremental mechanism improves the prediction precision and reduces false alarm and missing alarm.

The invention discloses a reinforcing method for long-term automatic grouting repair of fractured rock mass.The reinforcing method comprises the steps that a pressure sensor is arranged at the tail end of a grouting opening, and data of the pressure sensor are obtained through an intelligent control system; when the intelligent control system monitors that pressure difference is generated due to pressure unbalance caused by surrounding rock fracture development, the intelligent control system sets grouting parameters and starts a grouting program; in the grouting process, pressure balance between equipment and surrounding rock is maintained through a pressure adjusting module, and it is ensured that grout is stably conveyed within the set pressure range all the time in the conveying process after a grouting program is started; grouting pressure and flow are controlled in the grouting process; in the grouting process, the bacterial liquid and the cementing liquid are input in a separated conveying and on-site gathering mode; and accumulated liquid in the pipeline is rapidly removed after grouting is finished. By adopting the method, cracks can be continuously monitored and periodically repaired, and the manual intervention requirement is reduced. The modular design is convenient for maintenance and replacement of equipment, and the maintenance cost is reduced.

The invention provides a dust collection base station, a dust cup, a cleaning device and a dust collection method, and belongs to the field of cleaning devices. The dust collection base station comprises a base station body and an uncovering structure, a containing groove is formed in the end of the base station body, the uncovering structure is located on the side wall of the containing groove, and the uncovering structure is configured to trigger a dust discharging cover of a dust cup to be unlocked if air pressure in the containing groove is within a preset negative pressure range. Due to the fact that the air pressure in the containing groove is within the preset negative pressure range during unlocking, the air pressure difference between the interior of the dust cup and the interior of the containing groove is within the acceptable range, and impact generated when the dust discharging cover is opened under the action of the air pressure difference between the two sides is also within the acceptable range. The sundries in the dust cup enter the containing groove under the action of the air pressure difference in the dust cup and the containing groove, residues of the sundries in the dust cup are reduced or even avoided, and the situation that normal use of the cleaning device is affected due to the fact that impact generated when the sundries enter the containing groove is too large is avoided.

A system for detecting the presence of a wafer on a wafer handling robot. The system includes a robot having an end effector with a ledge portion having an opening; a vacuum pump; a conduit fluidly coupling the vacuum pump to the opening in the ledge portion; a pressure sensor located along the conduit to determine whether a measured pressure is within a target pressure range; and a wafer configured to be supported by the at least one end effector and spaced apart from the ledge portion by an air gap. When the wafer is supported by the at least one end effector in a proper position, the measured pressure is within the target pressure range. When the wafer is not supported by the wafer support structure or is supported by the wafer support structure in an improper position, the measured pressure is outside of the target pressure range.

According to the present disclosure, it is possible to suppress a change in a state of a gas. There is provided a technique that includes: (a) adjusting at least one selected from the group of a pressure and a temperature of a buffer space in a buffer chamber when the temperature of the buffer space is out of a pre-set temperature range or the pressure of the buffer space is out of a pre-set pressure range; and (b) processing a substrate by supplying a gas via the buffer chamber to a process chamber in which the substrate is processed.

The invention relates to a burn glove pressure monitoring method and device, a storage medium and electronic equipment, and relates to the technical field of pressure monitoring, and the method comprises the following steps: when each actual pressure is normal, based on a target area in a burn hand and at least one corresponding target pressure interval when an actual action posture appears, determining the pressure of the burn glove according to the target area; determining whether the actual pressure of the wound area is adjusted and optimized or not; if yes, determining a to-be-optimized area needing pressure adjustment and optimization from each wound area; determining a first appropriate pressure of the to-be-optimized area, and adjusting the actual pressure of the to-be-optimized area to the first appropriate pressure; and when abnormal pressure exists in the actual pressures, determining the wound area corresponding to the abnormal pressure as an abnormal area, determining a second suitable pressure of the abnormal area, and adjusting the actual pressure of the abnormal area as the second suitable pressure. The effect of the burn gloves on inhibiting scar hyperplasia can be improved.

The invention discloses an automatic switching metering method suitable for multiple ranges of a pressure gauge, and the method comprises the steps: S1, obtaining the information of a current pressure measurement environment, inputting a pressure range prediction model, and outputting an initial recommended range; s2, selecting a measurement parameter of a corresponding measuring range, and performing preliminary measurement on the pressure at the initial sampling frequency to obtain a preliminary measurement pressure value; s3, comparing the preliminarily measured pressure value with the upper range limit and the lower range limit of the selected range, and judging that a higher / lower range needs to be switched; s4, the calibration coefficient of the range to be switched is obtained and corrected, and a corrected pressure measurement value is obtained; s5, dynamically adjusting the sampling frequency; and S6, the pressure change rate is monitored in real time, and the measuring range capable of covering the current pressure change range is preferentially selected for measurement. According to the invention, multi-range intelligent switching of the pressure gauge is realized, and the measurement precision and response speed in the full-range range are improved.

The invention relates to a performance-programmable pressure sensor and a preparation method and application thereof.The preparation method of the performance-programmable pressure sensor comprises the steps that a PDMS soft template is prepared firstly, then an electrode layer base layer and an ion layer are prepared based on the PDMS soft template, a conductive film is deposited on the surface of the electrode layer base layer to obtain an electrode layer, and the electrode layer base layer and the ion layer are prepared. And finally, assembling the two electrode layers and one ion layer to prepare the pressure sensor with programmable performance. According to the structural design of the pressure sensor with the programmable performance, a gradient modulus and microstructure comprehensive strategy is provided, microstructures with different heights and rigid-flexible mixed materials are adopted to regulate and control the sensitivity and the detection range of the sensing device, and high-sensitivity sensing in a wide pressure range is achieved; meanwhile, the pressure sensor can adapt to a handwriting recognition application scene, the sensitivity or the sensing range can be improved, and accurate information is extracted and recognized through a machine learning model.

The invention belongs to the technical field of data processing, and particularly relates to an intelligent analysis method and system for valve performance test data, and the method comprises the steps: constructing a dynamic sensitivity factor capable of reflecting the system stability through analyzing the change rate of a flow time sequence and the fluctuation of a current time sequence, and generating a fatigue factor in combination with a pressure range; further, an abnormal pressure peak value caused by the water hammer effect is identified and quantified, and a fatigue factor is corrected to obtain a degradation acceleration factor which can better reflect real physical wear; finally, the composite dynamic features and the traditional static features are jointly input into a GBDT model for training, so that early failure symptoms can be captured, and the accuracy and reliability of prediction of the remaining service life of the valve are improved.

The invention discloses a blood bag continuous extrusion method and device, a medium and equipment. The method comprises the steps that the blood bag continuous extrusion process is divided into a plurality of extrusion stages; obtaining a target extrusion parameter, and generating a target pressure value corresponding to each extrusion stage; and the current extrusion pressure is collected, the current extrusion pressure is adjusted to the corresponding target pressure value based on the preset control scheme of each extrusion stage, and continuous extrusion is conducted till the preset extrusion ending condition is met. The extrusion process is divided into a plurality of stages, the actual extrusion pressure of a target monitoring point on a mother bag serves as system input, the running speed of a stepping motor is adjusted in real time through a PID algorithm, and therefore the whole extrusion process is controlled to be within a proper pressure range; and after the pressure reaches the target value, the whole extrusion process is subjected to pressure maintaining according to the set small target pressure, so that the preparation efficiency is high, the hemolysis phenomenon is avoided, the quality of the separation process and the product percent of pass are improved, and the risk of abnormal quality is reduced.

The invention relates to the technical field of electric digital data processing, in particular to a method and a system for monitoring the running state of leak detection equipment in an air tightness experiment, which comprises the following steps: acquiring historical pressure data and historical temperature data of the leak detection equipment under a normal working condition, and calculating the pressure range of the leak detection equipment; the range is adjusted based on the mean value and the standard deviation of the historical pressure, the ratio of the current temperature to the set standard temperature, the temperature compensation coefficient and the pressure compensation coefficient; an optimal pressure compensation coefficient and an optimal temperature compensation coefficient are obtained, and corrected pressure is calculated; if the corrected pressure exceeds a preset threshold value, timing is started, and if the duration of the threshold value exceeding the preset threshold value exceeds a set time threshold value, it is judged that the leakage detection equipment is abnormal. According to the invention, the problem of low accuracy of monitoring the operation state of the air tightness experiment leak detection equipment is solved.

A firearm suppressor having a core, a first end, a second end, a hollow bore extending along a longitudinal axis from the first to the second end, and an energy management structure. The first end of the suppressor includes a set of threads for connecting the suppressor to a firearm, and the bore includes a plurality of openings into the energy manager. The energy manager includes a plurality of chambers extending from the bore. A method of designing a firearm suppressor including setting a pressure range to be contained by the suppressor, establishing certain manufacturing parameters, choosing a structure for the core, modeling performance values for the core, selecting a geometry of the structure, and selecting a sleeve for the core.

The invention relates to the technical field of stacker-reclaimers, in particular to a bucket-wheel stacker-reclaimer grounding force detection method, which comprises the following steps of: pitching a cantilever beam to the highest point, releasing redundant back pressure of a hydraulic oil cylinder, detecting a pressure value of a rod cavity through a pressure measuring point on the hydraulic oil cylinder, and recording data; pitching the cantilever beam to the lowest point, releasing redundant back pressure of the hydraulic oil cylinder, detecting a pressure value of a rodless cavity through a pressure measuring point on the hydraulic oil cylinder, and recording data; comparing the measured pressure value with a rated pressure value of the hydraulic oil cylinder; if the pressure values of the two cavities are both within the rated pressure range of the hydraulic oil cylinder and the two cavities have 30% of allowance, the grounding force balance of the whole machine is considered to be qualified, and detection is ended; if the pressure value of one cavity is within the range of the rated pressure value of the hydraulic oil cylinder, but the allowance is less than 30%, the grounding force balance of the whole machine is judged to be unqualified, the balancing weight is adjusted, detection is performed again after adjustment, the detection method is relatively simple, and the balance of the whole machine is avoided after the balance weight is adjusted.

In some embodiments, a pressure sensor may comprise a housing, a flexible membrane which, together with the housing, forms a hermetically closed cavity, a sensor element arranged in the hermetically closed cavity, and a gaseous medium in the hermetically closed cavity. The sensor may detect a change in a physical property, of the flexible membrane, associated with an external pressure pressing inward into the flexible membrane of the hermetically closed cavity.

The invention provides a hydrogen production control method and related equipment, the hydrogen production control method is applied to a hydrogen production system, the hydrogen production system comprises a first valve and a second valve which are used for adjusting the internal pressure, the pressure adjusting speed of the second valve is larger than that of the first valve, and the hydrogen production control method comprises the steps that in the process that the hydrogen production system generates target gas, the target gas is generated; and controlling the hydrogen production rates of the first valve, the second valve and the hydrogen production system to adjust the internal pressure, so that the adjusted internal pressure of the hydrogen production system is within a preset target pressure range of the hydrogen production system. According to the technical scheme, the first valve and the second valve with different pressure adjusting speeds are adopted, and the internal pressure of the hydrogen production system is adjusted by combining the hydrogen production rate, so that the internal pressure of the hydrogen production system can be reasonably adjusted and stabilized to the preset target pressure range, and a better hydrogen production effect is achieved.

The invention discloses a double-drive servo press. The double-drive servo press comprises a rack, an upper punching device, a lower punching device, a feeding device and a die core. The upper punching device comprises two sets of driving mechanisms and an upper punching assembly, and the two sets of driving mechanisms are fixed to the top end of the rack and arranged in the X-axis direction. The lower punching device is composed of three stacked lower punching mechanisms, each mechanism is provided with a lower punching plate and two sets of driving mechanisms, the driving mechanisms are all arranged at the bottom of the rack, the lower punching plates of the three lower punching mechanisms are stacked in the Z-axis direction and connected to the two corresponding sets of driving mechanisms respectively, and the mold core is located in the center of the bottom of the rack and penetrates through the lower punching plates. The feeding device is installed on the side wall of the rack, and the feeding end of the feeding device is located on the upper surface of the third lower punching plate. The upper mechanism and the three sets of lower punching mechanisms are each provided with a dual-drive mechanism, the pressure range and synchronism of the press are improved, and meanwhile the size is reduced.

The invention discloses a modularized gas pressure controller with a replaceable measuring range and a gas pressure regulation and control method, and belongs to the technical field of mechanical measurement. The invention aims to solve the problems that the whole air pressure controller needs to be replaced in the air pressure regulation and control process, the operation is tedious and the replacement is inconvenient. The device comprises a box body and an air pressure measurement and control module detachably connected in the box body, a main control circuit board is fixedly connected in the box body, and the air pressure measurement and control module comprises a measurement and control circuit board, and a sensor and a reference sensor which are connected with the measurement and control circuit board; the main control circuit board is in communication connection with the measurement and control circuit board; the multiple air pressure measurement and control modules are identical in appearance specification, and each air pressure measurement and control module has a unique measuring range. According to the invention, the air pressure measurement and control module with the target air pressure range is selected according to needs and is installed in the box body, the operation is simple and rapid, meanwhile, 1ms process control is realized by using the rapid response of the reference sensor, and 0.01-level air pressure measurement high-precision output is realized by using the sensor.

The embodiment of the invention discloses a cover opening structure and a dust collecting method, and belongs to the field of cleaning devices. The dust collection base station comprises a base station body and an uncovering structure, a containing groove is formed in the end of the base station body, the uncovering structure is located on the side wall of the containing groove, and the uncovering structure is configured to trigger a dust discharging cover of a dust cup to be unlocked if air pressure in the containing groove is within a preset negative pressure range. Due to the fact that the air pressure in the containing groove is within the preset negative pressure range during unlocking, the air pressure difference between the interior of the dust cup and the interior of the containing groove is within the acceptable range, and impact generated when the dust discharging cover is opened under the action of the air pressure difference between the two sides is also within the acceptable range. The sundries in the dust cup enter the containing groove under the action of the air pressure difference in the dust cup and the containing groove, residues of the sundries in the dust cup are reduced or even avoided, and the situation that normal use of the cleaning device is affected due to the fact that impact generated when the sundries enter the containing groove is too large is avoided.

The utility model provides a controlled atmosphere fresh-keeping storehouse pressure balance valve which comprises a communicating piece and a breather valve connected to the end portion of the communicating piece, the breather valve is located on the outer side of a controlled atmosphere fresh-keeping storehouse, and the breather valve is communicated with the inner space of the controlled atmosphere fresh-keeping storehouse through the communicating piece. According to the pressure balance valve, the inner space of the controlled atmosphere fresh-keeping storehouse is communicated with the breather valve located outside the controlled atmosphere fresh-keeping storehouse through the communicating piece, and the breather valve ensures that the controlled atmosphere fresh-keeping storehouse is isolated from the atmosphere within a certain pressure range and can be communicated with the atmosphere when the pressure exceeds or is lower than the pressure range; therefore, loss of cold air in the air-conditioned fresh-keeping storehouse is reduced while it is guaranteed that the cold storage door of the air-conditioned fresh-keeping storehouse is easy to open, when the pressure balance valve of the air-conditioned fresh-keeping storehouse is arranged, only the communicating piece needs to penetrate through the wall body of the air-conditioned fresh-keeping storehouse to enable the inner space of the air-conditioned fresh-keeping storehouse to be communicated with the breather valve, and the arrangement cost is reduced.

The invention relates to the technical field of stoma nursing, and discloses a stoma chassis intelligent monitoring system which comprises a chassis device and a server which are arranged on a patient. The server side comprises a data acquisition module, an abnormity judgment module, a body position determination module, an analysis module, a strategy generation module and a sending module, and the analysis module is used for analyzing the body position data, the current pressure data, the current temperature data and the current humidity data according to the current body position data, the current pressure data, the current temperature data and the current humidity data on the basis of a corresponding stoma chassis pressure value corresponding table in a database. Matching a pressure reasonable value corresponding to the current body position data of the patient at the current moment from a stoma chassis pressure value corresponding table, wherein each pressure value in the stoma chassis pressure value corresponding table is within a preset pressure range; the strategy generation module is used for generating a telescopic adjustment scheme corresponding to an automatic telescopic mechanism in the chassis device at the current moment according to the current pressure data and the matched pressure reasonable value corresponding to the patient at the current moment under the current body position data.

The invention discloses a production storage tank storage performance detection system based on data analysis, and belongs to the technical field of production storage tank storage performance detection analysis. According to the scheme, internal environment storage data of a storage tank is collected and analyzed in real time, a plurality of collection points are set in storage tank equipment, and the measuring point temperature and the measuring point pressure of each collection point are obtained; the accuracy and comprehensiveness of collection and analysis of the internal environment of the storage tank are improved, a temperature change curve and a pressure change curve are described respectively, analysis and calculation are conducted by combining the maximum temperature value of a set temperature interval and the maximum pressure value of a set pressure interval, and abnormal collection points and storage risk coefficients are obtained. Whether the operation storage state of the storage tank meets the requirement or not is judged according to the storage risk coefficient, the judgment accuracy is improved, the environment influence coefficient of the abnormal collection point is obtained, whether the surrounding real-time environment is qualified or not is judged, comprehensive analysis is conducted from inside to outside, and targeted adjustment is conducted according to the judgment result.

The invention discloses a high-pressure liquid injection control method and equipment for a high-capacity battery, a medium and a product, and the method comprises the following steps: obtaining the model of a device to be injected with liquid, and determining a first deformation threshold value, a second deformation threshold value and a pressure interval according to the model of the device to be injected with liquid; when the pressure of the environment where the to-be-injected device is located is in the pressure interval, the deformation quantity of the to-be-injected device in the liquid injection process is obtained; when the deformation quantity is greater than a first deformation threshold value, controlling to stop actively changing the pressure difference between the interior of the to-be-injected device and the injection equipment; after the pressure difference between the interior of the to-be-injected device and the liquid injection equipment is controlled to stop actively changing, when the deformation quantity is smaller than a second deformation threshold value or reaches a preset duration, the pressure difference between the interior of the to-be-injected device and the liquid injection equipment is controlled to be actively changed; the step of determining the preset duration comprises the substeps of determining the pressure change rate of the environment where the to-be-injected device is located, and determining the preset duration according to the pressure change rate.

The present invention relates to the technical field of hydrogen nozzles, and in particular to a hydrogen nozzle, the technical solution of which includes a nozzle body, a throat, a compression spring screw and a plug, the nozzle body being a hollow cylindrical structure, and an air inlet being provided at the top of the nozzle body, a tip seat being fixedly mounted at the bottom of the nozzle body, a C-shaped hole being provided on one side of the interior of the nozzle body, and a flow channel being provided at a position away from the hole in the interior of the nozzle body. The present invention installs a slider inside the nozzle body, and adjusts the position of the slider by the combined force of the elastic force applied to the slider by a spring and the pressure applied by hydrogen entering the nozzle body, thereby causing the slider to block the flow channel to varying degrees, thereby adjusting the flow velocity of hydrogen inside the nozzle body, thereby achieving the purpose of adjusting the internal pressure of the hydrogen nozzle, and enabling hydrogen to maintain a relatively stable pressure range during transportation, thereby avoiding damage to the equipment caused by large pressure fluctuations.

The invention provides a fuel cell system and a start-up control method and device thereof.The start-up control method of the fuel cell system comprises the steps that when a system start-up instruction is received, the pressure of the cathode side in an electric pile is obtained; comparing the acquired pressure of the cathode side with a preset pressure range; when the obtained pressure of the cathode side is not within the preset pressure range, an exhaust control valve on an air exhaust pipeline connected with the cathode side is opened; when the obtained pressure of the cathode side is within the preset pressure range, the exhaust control valve is closed; and after the exhaust control valve is closed, controlling the fuel cell system to start according to a preset starting process. The start-up control method of the fuel cell system is beneficial to reducing the failure rate of the fuel cell system during start-up and prolonging the service life of the fuel cell system, and has good practicability.

The invention discloses an integrated oxygen cabin, and relates to the technical field of oxygen cabins, the integrated oxygen cabin comprises a cabin body and a cabin door arranged on the cabin body, the cabin body is provided with an equipment room, an oxygen generation system, a pressure regulating system, an environment regulating system and an electric control system are arranged in the equipment room, and an oxygen source interface is arranged on the side wall of the cabin body. The oxygen generation system is communicated with the oxygen source interface and used for supplying oxygen to the oxygen source interface, and the oxygen source interface is used for being connected with a nasal oxygen cannula or an ear tag; the pressure regulating system is used for regulating the air pressure in the cabin body and keeping the air pressure in the cabin body constant in a set pressure range; the environment adjusting system is used for adjusting the environment temperature in the cabin body; the electric control system is electrically connected with the oxygen generation system, the pressure regulating system and the environment regulating system respectively. The oxygen production system, the pressure regulating system, the environment regulating system and the electric control system are integrated in one equipment room, so that the occupied space is reduced, and carrying and mounting are convenient.

Disclosed example pressure transducers include: a pressure housing comprising a first cavity; a fluid input line configured to provide a fluid to the first cavity; a first pressure measurement assembly having a first type and configured to output a first measurement signal based on a pressure of the fluid in the first cavity; a second pressure measurement assembly having a second type and configured to output a second measurement signal based on the pressure of the fluid in the first cavity; and a controller configured to determine the pressure of the fluid in the first cavity based on the first measurement signal when the pressure is within a first range and determine the pressure of the fluid in the first cavity based on the second measurement signal when the pressure is within a second range.

The invention relates to the technical field of motor rotating speed testing, in particular to a load rotating speed testing device for a new energy automobile. According to the technical scheme, the device comprises a positioning pipeline assembly, a motor connecting assembly is installed in the positioning pipeline assembly, an auxiliary installation assembly is installed outside the positioning pipeline assembly, and a testing assembly is attached to the side, penetrating through the positioning pipeline assembly, of the motor connecting assembly. According to the invention, the two side edges of the plurality of clamping frames are attached to the side edges of the driving wheel and the test roller, so that when a vehicle is detected, because the installation precision of the coupling is not enough or the pressure applied to the coupling is too large, the motor output shaft and the power measurement unit of the test device are eccentric; when additional vibration is generated, the device is prevented from being separated from the pressure range provided by the test roller, thereby avoiding displacement deviation of the test roller or measurement errors caused by vibration of the driving wheel.

The invention discloses a self-calibration flexible pressure sensing device, which comprises a first conductor and a second conductor which are in a strip-shaped, strip-shaped or linear structure and both have a piezoresistive effect. The isolating layer is arranged between the first conductor and the second conductor, and through holes or long grooves with continuous through holes are distributed in the surface of the isolating layer; and an encapsulation layer covering the first conductor and the second conductor. According to the embodiment of the invention, a dual-core layer piezoresistive structure and a through hole type isolation layer design are adopted, the dual-core layer design covers a range from small pressure to large pressure, the range limitation of a single material is broken through, and a dynamic self-calibration technology is combined, so that multi-parameter integrated detection of pressure magnitude, position and width is realized; the sensor array has the advantages of self-adaption to environment change, wide-range detection, multi-scene applicability and the like, the sensor for realizing the functions only needs four wires, complex wiring of the sensor array is avoided, miniaturization and flexibility are facilitated, a narrow strip-shaped flexible structure is adopted as a whole, and flexible arrangement of sensor tracks and garment integration are facilitated.

The invention relates to an oil pump device control method and relates to the technical field of pump structures. The containing cavity is communicated with the air inlet, so that external air can enter the containing cavity through the air inlet, the pressure in the cylinder body is increased, the containing cavity is communicated with the exhaust port, so that air in the cylinder body can be exhausted out of the containing cavity through the air outlet, the pressure in the cylinder body is reduced, and then the pressure value in the containing cavity of the cylinder body is adjusted. As the containing cavity of the cylinder body is communicated with the containing cavity of the pressure stabilizing cylinder, according to the fluid statics principle, the pressures of all points of static fluid in the communicating container are equal, that is, the pressure value in the containing cavity is equivalent to the pressure value of the containing cavity in the cylinder body, and according to the relation between the pressure value in the containing cavity and the preset pressure value, the pressure value of the pressure stabilizing cylinder is obtained. According to the oil pump device, whether the pressure in the containing cavity is large or small is judged, then air inflow or air exhaust of the cylinder body is controlled, the pressure value in the containing cavity is kept within the target pressure range, the oil pump device can stably output, and the stability of the oil pump device is improved.

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.