55results about How to "Prevent reverse flow" patented technology

An apparatus and a method for power supply are provided. The apparatus for power supply includes a main power circuit, an auxiliary power circuit and a power switching control circuit. The main power circuit is configured to generate a main power suitable to be provided to a first load and a second load for use. The auxiliary power circuit is configured to generate an auxiliary power suitable to be provided to the second load for use. The power switching control circuit is configured to detect a voltage difference between the main power and the auxiliary power and determine whether the apparatus meets a normal power supply condition, so as to select one of the main power and auxiliary power as a power source of the second load.

The invention provides a kitchen lampblack discharge system which has good effect and is convenient to maintain. The kitchen lampblack discharge system comprises a range hood, a check valve, a smoke discharge pipe and a public flue, wherein the smoke discharge pipe is directly and hermetically connected with the public flue, the check valve comprises a vertical pipe which is internally provided with a circular valve plate, the valve plate is rotatably supported on the pipe wall of the vertical pipe by virtue of a transverse shaft which radially penetrates through the valve plate, and the pipe wall of the vertical pipe is provided with a blocking point; when the valve plate is in a horizontal state, the edge of the valve plate is depressed on the blocking point, a weight gain plate is fixed on the valve plate which is located above the blocking point and is close to the blocking point, the upper end and lower end of the vertical pipe are respectively sleeved on the lower end of the smoke discharge pipe and the air outlet of the range hood. In the invention, the check valve is additionally arranged between the air outlet of the range hood and the smoke discharge pipe, and the check valve is connected with the air outlet of the range hood and the smoke discharge pipe in a dismountable way, so as to be convenient to dismount and clean.

The invention discloses a self-cleaning pipeline filter device for water conservancy projects, which comprises a filter pipe, the filter pipe includes a water inlet and a sewage outlet, a slag discharge pipe is installed on the side wall of the filter pipe, and a slag discharge pipe is installed on the slag discharge pipe A pressure valve is installed, and a filter screen and a fixed ring are installed on the inner wall of the filter pipe, and the filter screen and the fixed ring are both located between the two joints of the slag discharge pipe and the filter pipe, and the fixed ring is close to the filter screen. A spring is installed at one end, a piston is installed at one end of the spring close to the filter screen, and a clear water pipe is installed on the side wall of the filter pipe. In the present invention, after the filter screen is blocked, the pressure of the slag discharge pipe is greater than that of the filter pipe, so that the water flows along the slag discharge pipe and forms a negative pressure to peel off the impurities on the clean filter screen, and the clean water pipe is blocked by the piston to prevent the sewage from entering, and the clean water pipe and the sewage pipe are discharged side by side. It is set so that when the filter screen is clogged, the clean water pipe can be closed and the sewage pipe can be opened for self-cleaning, and the speed of self-cleaning can be further increased through the needles to save water resources.