47results about How to "Stable pressure control" patented technology

The inkjet recording apparatus includes: an inkjet recording head which includes a nozzle through which liquid is ejected; a pressure regulating unit which includes a liquid chamber that communicates with the nozzle and a gas chamber that is partitioned from the liquid chamber by a flexible film; and a liquid chamber pressure controlling device which controls a pressure of the liquid chamber to a predetermined negative pressure when carrying out back pressure control in which back pressure is applied to the liquid inside the nozzle, wherein: the flexible film causes change in the pressure of the liquid chamber when the liquid is supplied for at least a predetermined supply amount to the liquid chamber in a state where the gas chamber is open to air; and the liquid chamber pressure controlling device carries out the back pressure control after controlling the pressure of the liquid chamber to a predetermined value of positive pressure by supplying the liquid of at least the predetermined supply amount to the liquid chamber.

A vehicle brake hydraulic pressure control apparatus includes a hydraulic pressure adjusting unit, a split road determining section, a differential pressure control section, and a hydraulic pressure adjusting and driving section. The hydraulic pressure adjusting unit individually adjusts brake fluid pressures acting on wheel brakes for wheels. The split road determining section determines whether road surfaces which the wheels are in contact with constitute a split road. In a state where the split road determining section determines during execution of antilock braking control that the road surfaces constitute the split road, the differential pressure control section determines command pressures for the wheel brakes so that differential pressures between the brake fluid pressures of the right and left wheel brakes are equal to or less than a permissible differential pressure. The hydraulic pressure adjusting and driving section controls the hydraulic pressure adjusting unit based on the determined command pressures.

The invention relates to an energy-saving optimization control method for industrial circulating water based on double-layer structure predictive control, which comprises the steps of building a dynamic model and steady-state model of a circulating water system; setting the priority of a controlled variable, the priority of an operating variable, the benefit direction of the operating variable andthe correlation direction between the operating variable and the controlled variable; establishing an objective function, and constructing constraint conditions according to technological conditionsand the steady-state model; if there is a feasible region, acquiring an optimal operating point; otherwise, properly loosening the constraint conditions for the controlled variable to obtain the optimal operating point; enabling the obtained optimal operating point to serve as a set value, building a model prediction controller, and implementing a control action. The energy-saving optimization control method realizes that each production unit of the circulating water system operates with the return water temperature being always below the highest allowable temperature. Meanwhile, the pipe network output flow of the circulating water system is enabled to be reduced, and the pressure is reduced. Therefore, the energy-saving optimization control method realizes the effects that the operationcost is reduced, and the system is energy-saving.

The invention discloses a metallographic grinder and a method for polishing a metallographic sample of a corrosion layer of a battery electrode plate, which can effectively reduce the labor intensity of a grinding operation and improve the grinding efficiency, and is beneficial of obtaining clearly displayed metallographic structures. The metallographic grinder comprises a rotatably arranged grinding wheel, a driving motor, a vertical guide post, a lifting platform, a manual lifting executor, a horizontal guide rod, an electrode plate mounting plate and a translation device, wherein the driving motor is used for driving the grinding wheel to rotate, the vertical guide post is arranged on a rack, the lifting platform can lift up and down along the vertical guide post, the manual lifting executor is used for driving the lifting platform to move up and down in a reciprocating manner, the horizontal guide rod is arranged on the lifting platform, the electrode plate mounting device can move along the horizontal guide rod, and the translation device is arranged on the lifting platform and is used for driving the electrode plate mounting device to move along the horizontal guide rod.

The invention relates to vacuum pressurizing and dipping equipment for producing wood plastic composite. The vacuum pressurizing and dipping equipment mainly comprises the following five parts: a pressure control system I, a temperature control system II, a protection system III, a vacuum system IV and a dipping system V. In a wood plastic composite production process, the pressure control system I, the vacuum system IV and the temperature control system II can be conveniently used for automatically compensating pressure, automatically regulating the vacuum degree and automatically controlling the temperature for producing according to a specified production process; inert gas can be used as protective gas by the protection system III, and the protective gas is collected by a gas collection bottle (6) after production; the dipping system is equipment integrating the functions of wood dipping and heating into a whole, and a slide way (16) and a slide wheel (15) are arranged in the dipping equipment and are convenient for putting wood before dipping and taking out the wood after dipping; and a floating prevention piece (19) can be used for preventing wood from floating above dipping liquid in a dipping process. The vacuum pressurizing and dipping equipment has the characteristics of energy saving, environmental protection, convenience in operation and practicability.

A hydraulic elevator system using energy accumulator to improve its running performance features that a drive motor whose speed is regulated by changing voltage and frequency is used to change the flow of hydraulic pump. It is composed of cage, asynchronous motor, hydraulic pump electromagnetic valve, oil cylinder, hydraulic energy accumulator and two pressure transducers, which can measure and feed back the pressure of hydraulic pump and oil cylinder to form a pressure closed-loop system for conpensating leakage.

The invention provides a cabin of an underwater detecting instrument. The cabin of the underwater detecting instrument has certain anti-pressure ability at a great depth underwater and cannot be deformed obviously. The cabin is formed by at least two high strength spherical cabin bodies in a nested mode, the cabin bodies are connected through elastic buffer devices, and the interlayer formed between the cabin bodies is filled with liquid state substances. By the adoption of the structure, the problem that a cabin of the underwater detecting instrument can be damaged due to deepwater pressure in the prior art is solved, and thus the safety of important instrument equipment and personnel in the cabin can be guaranteed.

A controller of an injection molding machine which compensates a delay in an injection velocity changeover and a delay at the time of changeover to the pressure-holding process, and is capable of more accurate and stable injection velocity control and changing control from the injection velocity control to pressure control. In the injection process, a motion command is outputted in every sampling period τ according to the command injection velocity. When a screw position overshoots the set velocity changeover positions Psw(2) and Psw(1), a motion command based on a velocity command of the next interval is outputted from the next period. However, there is time lag between the point when the set changeover position is reached and the point when the motion command is changed after detection thereof. There generates a motion deficiency in a motion amount shown by mark A and overshoot shown by B. Motion commands of the next period or the next and subsequent several periods are compensated with errors in the motion amount caused by the time lag used as compensation amounts A′ and B′. The generated error motion amount is immediately compensated, which enables accurate velocity changing control. By performing the compensation in the same manner when the injection velocity control is switched to the holding pressure control, it is possible to suppress the peak pressure and the dispersion.

The invention discloses an LNG (Liquefied Natural Gas) vehicle-mounted gas cylinder supercharging system. The LNG vehicle-mounted gas cylinder supercharging system comprises a gas cylinder, a vaporizer, a buffer tank and a controller. The LNG vehicle-mounted gas cylinder supercharging system is characterized in that one end of the vaporizer is connected to the gas cylinder via a pipeline; the mounting height of the vaporizer is lower than the lowest liquid level of the gas cylinder; the other end of the vaporizer is connected to the buffer tank; one output of the buffer tank is connected to an engine and the other output of the buffer tank is connected to the gas cylinder via a circulating pump; a temperature sensor, an electric heater and a pressure sensor are arranged in the buffer tank and are connected with the controller via a circuit; meanwhile the controller is connected with the circulating pump to control the working state of the circulating pump. The LNG vehicle-mounted gas cylinder supercharging system disclosed by the invention is not affected by any use condition and environment temperature, the pressure is stably controlled, the stable working of the engine is guaranteed, meanwhile the fuel waste is reduced, the environmental protection is improved and the use safety is enhanced.

In order to perform stable pressure control, provided is a control device for an injection molding machine which comprises: a filling/pressure keeping assessment unit which assesses whether or not the injection molding machine is performing a pressure keeping operation (Step ST3); an elastic constant identification unit which, when the filling/pressure keeping assessment unit assesses that the pressure keeping operation is performed (Yes in Step ST3), acquires a pressure detection value and a position detection value as motor operation information (Step ST4), and identifies an elastic constant K on the basis of the acquired pressure detection value and position detection value (Step ST7); and a pressure control parameter setting unit which calculates a proportional gain Ka of a pressure control unit so that a product of the proportional gain Ka of the pressure control unit and the elastic constant K is smaller than a velocity control band Omegasc of a velocity control unit (Step ST8), and sets the pressure control unit to the calculated proportional gain Ka(Step ST9).

The invention relates to a gasification/combustion performance testing device and a use method thereof, in particular to a gasification/combustion performance testing device for solid fuel under a pressurized oxygen-water vapor condition and a use method of the gasification/combustion performance testing device, aims to solve the problem that an experimental research system and method for pressurized oxygen-water vapor combustion mode performance evaluation are unavailable at present. The device consists of an inert gas tank, an oxygen tank, a high-pressure constant-flow water injection pump, a powder feeder, a preheating furnace, a heating belt, a premixing tank, a sample injection gun, a one-dimensional furnace, a sampling gun, a gas-solid separator, a high-temperature-resistant back pressure valve, a constant-temperature box, a water-vapor separator and a flue gas analyzer. The method comprises the steps that: solid fuel particles are placed in the powder feeder, the inert gas tank is opened, the one-dimensional furnace is heated, the inert gas tank and the oxygen tank are opened, the high-pressure constant-flow water injection pump is started,the high-temperature-resistant back pressure valve is adjusted,the powder feeder is started for thermochemical conversion, and meanwhile gas phase detection is conducted; and the water injection pump, the inert gas tank and the oxygen tank are closed, the high-temperature-resistant back pressure valve is adjusted, heating and residual particle sample and condensate water detection are turned off, and operation is repeated.

The invention relates to a pressure regulating device, and particularly relates to an automatic nitrogen pressure regulating control device of refining and cracking buffer tanks. The automatic nitrogen pressure regulating control device and is composed of the cracking buffer tank, the refining buffer tank and a nitrogen charging pipeline; the device is characterized in that a top pipeline of the refining buffer tank is connected to the upper part of the cracking buffer tank, and the top of the cracking buffer tank is connected with the nitrogen charging pipeline through a nitrogen control valve; a blow-down pipeline connected by an air release valve, is arranged between the top of the cracking buffer tank and the nitrogen control valve, and the nitrogen control valve and the air release valve are connected with a pressure balance switch controller through a circuit. The automatic nitrogen pressure regulating control device of the refining and cracking buffer tanks, provided by the invention, has the advantages that the structure is reasonable, the operation is smooth and stable, and the pressure control is stable; a condition that the pressures in the refining buffer tank and the cracking buffer tank are stable is guaranteed through practical verification, the normal operation of a feeding pump of the refining and cracking buffer tanks is guaranteed, and the safe and stable production purpose is achieved.

The invention relates to a pressure regulating type pressure control valve. The pressure regulating type pressure control valve comprises a first shell. A pipe fluid inlet is formed in one end of the first shell, a pipe fluid outlet is formed in the side wall of the first shell, and a thrust spring component is sleeved with the first shell. The other end of the first shell is connected with a second shell, and a thrust spring pushing unit abutting against the thrust spring component is arranged in the second shell. One end of the inside of the first shell is sleeved with a first ball seat, one end of the first ball seat abuts against the inside of the first shell, and the other end of the first ball seat abuts against a sealed ball. The other side of the sealed ball abuts against a second ball seat, an axial interval annular space between the first ball seat and the second ball seat forms an annular fluid channel which is communicated with the pipe fluid outlet, and the other end of the second ball seat abuts against one end of the thrust spring component. By means of the pressure regulating type pressure control valve, the problems of pressure holding, equipment damage and leakage of fluid caused by small-range fluctuation of flow can be effectively solved, the pressure control is stable during working, the structure is simple, and the usage is convenient.

The invention relates to a self-operated regulating valve for a boiler gas pipeline. The self-operated regulating valve comprises a main body, an electromagnetic induction module, a piezoelectric transmitter, a controller and a pulse current generator, and is characterized in that an electromagnetic induction coil, the piezoelectric transmitter, the pulse current generator and the controller are additionally arranged on the existing self-operated regulating valve; and when a boiler combustor is closed or the upstream/downstream pipeline pressure of the self-operated regulating valve fluctuates, axial pulse electromagnetic force is applied to a valve element through the electromagnetic induction coil, and the response speed and the regulating stability of the regulating valve are improved.