933 results about "Pressure controlled method" patented technology

The present invention provides a pressure control method and apparatus of an electric pressure cooker, and the electric pressure cooker. The method comprises a detection step that a temperature wrap disposed at the bottom of the electric pressure cooker detects temperature of the electric pressure cooker; and a heating device control step of controlling on and off of a heating device according to the temperature detected by the temperature wrap when a pressure switch is off, specifically, opening the heating device to heat when the temperature is less than or equal to first temperature, and closing the heating device and stopping heating when the temperature is great than or equal to second temperature, wherein the second temperature is greater than the first temperature, the first temperature is great than or equal to 100 DEG C and less than or equal to 108 DEG C, and the second temperature is great than or equal to 102 DEG C and less than or equal to 110 DEG C. According to the technical scheme, cycle control of the pressure in a certain range is achieved through a single pressure switch without internal temperature-sensitive monitoring, and use functions of the electric pressure cooker are improved.

The invention discloses a pressure control method of an electric pressure cooker. The pressure control method comprises the following steps: obtaining the coordinates of the place of the electric pressure cooker; inputting the boiling point of the place of the electric pressure cooker; receiving the boiling point and making a scheme of pressure and temperature in the cooker; setting a cooking time period according to a food material; correspondingly setting the pressure and temperature in the cooker for each cooking time period; storing. According to the pressure control method disclosed by the invention, communication between a mobile terminal and the electric pressure cooker can be realized through the mobile terminal; the position coordinates of the electric pressure cooker are acquired through the mobile terminal; the altitude value of the place is inquired according to the position coordinates, and the boiling point value at the electric pressure cooker is obtained according to the altitude value; a cooking scheme is designated for the food material according to the boiling point value; the method disclosed by the invention realizes independent control of different places, different altitudes and different foods.

The invention discloses a pressure control method of an air conditioning system. The pressure control method comprises the following steps: S1, respectively comparing detected outdoor ambient temperature and exhaust pressure of a compressor with a preset temperature range and preset pressure, judging whether to reduce the exhaust pressure or not according to comparison results, and if so, starting the step S2; S2, reducing the rotational speed of an indoor fan during refrigeration and reducing the rotational speed of an outdoor fan during heating; S3, comparing detected degree of superheat of inhaled air or exhaust pressure with preset degree of superheat or preset exhaust pressure, judging whether to withdraw from the control of reducing the exhaust pressure or not according to the comparison results, and if so, starting the step S4; S4, stopping the reduction of the rotational speed of the indoor fan during refrigeration and stopping the reduction of the rotational speed of the outdoor fan during heating. Through the adoption of the pressure control method of the air conditioning system disclosed by the invention, the exhaust pressure of the system can be controlled within a certain range; furthermore, the method is low in cost and good in effects, and cannot impact the reliability of the air conditioning system.

A system for reverse circulation in a wellbore include equipment for supplying drilling fluid into the wellbore bit via at least an annulus of the wellbore and returning the drilling fluid to a surface location via at least a bore of a wellbore tubular. The system also includes devices for controlling the annulus pressure associated with this reverse circulation. In one embodiment, an active pressure differential device increases the pressure wellbore annulus to at least partially offset a circulating pressure loss. In other embodiments, the system includes devices for decreasing the pressure in the annulus of the wellbore. For offshore application, annulus pressure is decreased to accommodate the pore and fracture pressures of a subsea formation. In still other embodiments, annulus pressure is decreased to cause an underbalanced condition in the well.

The invention relates to a pneumatic engine for car use and discloses a pneumatic engine for car use with an adjustable expansion ratio and an exhaust pressure control method. According to the pneumatic engine for car use with the adjustable expansion ratio, compressed air is expanded in a cylinder so as to propel a piston and drive a crankshaft to rotate through a connecting rod and output rotating mechanical work to the outside. The pneumatic engine is characterized in that the pneumatic engine comprises an air inlet electromagnetic valve which is arranged in a cylinder air inlet pipe, an exhaust electromagnetic valve which is arranged in a cylinder exhaust pipe, a pressure sensor which is used for detecting the air pressure inside the cylinder, a photoelectric encoder which is used for detecting a crankshaft rotation angle, and a controller; and the controller makes a policy according to the cylinder air pressure detected by the pressure sensor and the crankshaft rotation angle of the photoelectric encoder, and sends a control signal of opening or closing to the air inlet electromagnetic valve and the exhaust electromagnetic valve. The pneumatic engine reduces the compressed air available energy loss caused by high pressure exhaust, thereby improving the energy conversion rate of the pneumatic engine.

Disclosed is a diesel engine variable-altitude boost pressure control method. Through a two-level adjustable booster controller ECU, according to change of altitude, diesel engine rotation speed and loads, opening of a high-pressure stage VGT vane of a two-level adjustable booster and opening of a high-pressure stage turbine regulating valve and a low-pressure stage turbine regulating valve are controlled in real time, optimal control is conducted on boost pressure in a variable-altitude and variable-working-condition mode, and the purpose that in the 0 m-5500 m altitude range, all performance indicators of a diesel engine are always kept the same as the performance under the plain conditions is achieved. The mode that feedforward control and fuzzy PID control are combined is adopted for the diesel engine variable-altitude boost pressure control method, and the boost pressure can be adjusted in real time according to change of altitude and working conditions of the diesel engine, so that the requirements for best power performance and fuel economy in the steady state working condition and the transient state working condition are met, the objective that power of the diesel engine at the altitude 5500 m fixed point is recovered to 95% or above that on plains is achieved, turbo lag is relieved, and pumping loss work is reduced. Meanwhile, the problems of gas compressor surges, turbine overspeed, excessively high turbine-front discharge temperature and the like are avoided.

The invention discloses a breathing machine control method and a breathing machine applying the control method. The breathing machine comprises a flow sensor, a pressure sensor, a microcontroller, a motor power amplifier and a blower. The breathing machine adopts a breathing synchronization pressure control method; particularly, the flow sensor detects the change in the flow of a pipeline, an expiration state and an inspiration state of a patient are judged according to a set flow threshold; and further, a preset pressure level is selected for switching according to the breathing state. Generally, when inspiration is converted into expiration in an air path system, man-machine confrontation is caused due to air accumulation at a nasal mask end. Therefore, a deviation between a set inspiration duration and a forecast duration serves as a time stamp of the beginning of the expiration after adjustment. The lower expiratory pressure is selected in advance, so that the pressure can be released timely, the man-machine confrontation is eliminated, and the man-machine synchronism is improved. The control mode meets breathing physiology requirements of people, and the breathing comfort and effectiveness of the patient are guaranteed.

The invention provides a pressure control method and control device for an air conditioner and the air conditioner. The pressure control method for the air conditioner comprises the steps that 1, therunning mode of the air conditioner is detected; 2, the air exhaust pressure and the air return pressure of a compressor in the air conditioner are detected; and 3, the rotation speed of an outer fanand an inner fan in the air conditioner is controlled according to the running mode of the air conditioner, the air exhaust pressure and the air return pressure. According to the pressure control method and control device for the air conditioner and the air conditioner, the unit running pressure is continuously detected, the rotation speed of the outer fan or the inner fan is correspondingly adjusted according to comparison of the air exhaust pressure and the air return pressure with a preset value, therefore, the unit running pressure is in an appropriate range value, and the unit jumping phenomenon caused by high-pressure protection or low-pressure protection is prevented; and the control method is high in accuracy, has no delay and is simple and reliable.

The invention discloses a static-pressure variable control method of wind-variable air conditioning system, which comprises several wind-variable terminal with valve feedback parallel connected on one wind tube of air conditioner which has a fan frequency changer and a wind tube static pressure sensor on the wind tube, while the sensor is connected with one input of controller. The output of controller is connected to the fan frequency changer. The wind-variable terminal is connected to another input of controller. Or the air conditioner has several wind tubes while each tube is arranged with a wind tube static pressure sensor. The invention can adjust the fan frequency via the static pressure of wind tube, to realize stable and reliable control, while it can reduce the static pressure via the valve signal of wind-variable terminal at local load, to save energy.

A remote pressure-controlled three-way valve device has a plunger axially traversed by an inlet passage normally closed by a spring-urged inlet valve. The plunger's outer sidewall has a recess in which an O-ring extends to abut against the steps of the recess to limit the plunger stroke and keep an outlet passage closed to a venting port formed in the sidewall of the body of the device. O-ring prevents short-circuits between the inlet passage and the vent port and a spring for counteracting friction between the O-ring and the device inner wall. Filters arranged in respective ports connectable to the input air-pressure supply and the tire inner tube provide fixed seats for the springs to bear on. The plunger may dwell in a stable intermediate position that opens the outlet or deflation passage is controlled by sending an air pressure through the inlet port at 50% of the normal pressure.

The invention discloses a control method of a modular multi-level current converter. According to the control method, 2N sub modules of a bridge arm is divided into N+1 module groups according to 20, 21, 22, and so on, and 2N-1, and 1, and during work, intra-group sub modules in each group are kept the same in state, namely being simultaneously turned on or turned off. Each group is configured with a voltage sensor used for measuring the voltage value of the group. According to such a structure, a voltage stability control method, a voltage recording method, a modulation method and an even pressure control method are designed. Voltage stability control adopts a PI adjustor to stabilize the sum of capacitor voltage of all sub modules of all phases; the voltage recording method is used for saving voltage values of all the module groups; the modulation method is used for determining the on-off state of each module group; even pressure control is used for keeping the average value of the sub modules of a component to be balanced. According to the control method provided by the invention, a control way of grouping sub module groups is adopted, voltage transformers required in an MMC system are greatly reduced, and further, hardware complexity of the system is reduced and the cost of MMC is reduced.

The present invention relates to an ink supply system used for an ink-jet printer, and an ink pressure control method in the system. Aiming at an ink gun 1 possessing a nozzle 41 and a pressure chamber 48, the ink is supplied circularly from a sub can 3 via an ink circulation path 2, at the upstream side of the ink gun 1, a pressure sensor 21 is configured, and at the downstream side, a pressure sensor 22 is configured. The flow path resistance R1 between the pressure sensor 21 and the ink gun 1 and the flow path resistance R2 between the pressure sensor 22 and the ink gun 1 are set to be equal R1=R2. A controller 10 calculates the ink pressure at the nozzle 41 according to the detection values of the pressure sensors 21, 22, so that the pressure in the sub can 3 is controlled in a manner of enabling the pressure to be a specified value.

Disclosed is a redundancy device for pressure control of a brake cylinder. The redundancy device for pressure control of the brake cylinder comprises a total air filter, a pressure regulating valve, an air charging solenoid valve, a first air exhaust solenoid valve and a second air exhaust solenoid valve, and further comprises a first pressure sensor, a switching solenoid valve and a second pressure sensor, wherein the total air filter, the pressure regulating valve, the air charging solenoid valve and the first air exhaust solenoid valve are arranged in a total air inlet in sequence, the second air exhaust solenoid valve is arranged between the total air filter and the pressure regulating valve. Due to the fact that the second pressure sensor is added, a brake control unit can detect whether the first pressure sensor has a fault or not at first, the first pressure sensor is switched to the second pressure sensor under the condition that the first pressure sensor has a fault, double guarantees are achieved, and the reliability of a system is improved. In addition, the brake control unit outputs control instructions according to the states of the first pressure sensor and the second pressure sensor and the current state of a locomotive so as to control the corresponding solenoid valves to change air channels, and therefore the regulating speed is high, and the control accuracy is high.

The invention relates to an active disturbance observation-based fuel pressure control method, aims at solving the problems of time-varying characteristics and non-linearity of an internal combustion engine fuel injection system and non-ideal application of traditional PID (proportion integration differentiation) control in fuel pressure control and the like, and provides the method of realizing control on fuel pressure by adopting model-based feedforward control and state observation-based feedback control. The method mainly comprises target fuel pressure computation, fuel pressure sensor practical fuel pressure collection and computation, fuel measuring unit fuel volume flow rate feedback regulation amount computation, fuel measuring unit fuel volume flow rate feedforward control amount computation, conversion of fuel measuring unit fuel volume flow rate into current, conversion of fuel measuring unit current into a PWM (Pulse Width Modulation) duty ratio, fuel measuring unit practical work current measurement and computation, a fuel measuring unit current feedback regulator, fuel measuring unit PWM modulation frequency computation, a fuel measuring unit PWM drive, a fuel measuring unit, a fuel injection system and a fuel pressure active disturbance observer.

A leak diagnosing technology in which a diagnostic space capable of being closed is defined which includes therein a fuel tank and a canister, the closed diagnostic space being pressurized by an air pump to diagnose of presence or absence of a leak in the diagnostic space based on whether or not a pressure in the diagnostic space indicates a predetermined pressure change. When the diagnosis is completed, the air pump is reversely rotated to cause a reduction in the pressure in the diagnostic space to thereby quickly return the pressure to a target pressure in a steady state.

The invention provides a chamber pressure control method, which comprises: step 100, acquiring air delivery target flow required when a chamber is in a target pressure according to a corresponding relationship between the pressure of the chamber and the air delivery flow; and step 200, setting the air delivery target flow as a flow setting value of a mass flow controller, wherein the mass flow controller implements air delivery operation on the chamber based on the flow setting value and controls the pressure of the chamber within the target pressure range. The method for controlling the pressure of the chamber also comprises a step of acquiring the corresponding relationship between the pressure of the chamber and the air delivery flow. In addition, the invention also provides a chamber pressure control device, a chamber pressure control system using the method and the chamber pressure control system using the device. An expensive pressure control valve is replaced by adopting the cheaper mass flow controller and the simple control step, and the cost of the process/equipment is saved while effectively controlling the pressure of the chamber.