Please select the most similar patent number from A, B, C and D. Which number is?
A water and fertilizer air-heat irrigation device, comprising: a water tank (1), a fertilizer tank (2) above the water tank (1), a water pump (3) and a heating device (7); the fertilizer tank (2) is in communication with the water tank (1) by means of fertilizer delivery pipes (11), flow control devices are provided in the fertilizer delivery pipes (11), a water level sensor is provided in the water tank (1), and the water level sensor is connected to a controller by means of an electrical signal. Said device can ensure the ratio of water to fertilizer in the water tank and achieve the purpose of continuous fertilization.
A: The present invention relates to the technical field of battery manufacturing, and particularly relates to an external water circulation temperature control system for a fuel cell fixture. The system of the present invention comprises a fixture provided with a water inlet and a water outlet in mutual communication with each other. The water outlet communicates with a constant-temperature water mixing container via a first circulation water pump, and the constant-temperature water mixing container is provided with a first temperature sensor. A hot water delivery pipeline used to deliver hot water into the constant-temperature water mixing container and a cold water delivery pipeline used to deliver cold water into the constant-temperature water mixing container are provided between the first circulation water pump and the constant-temperature water mixing container. The constant-temperature water mixing container communicates with the water inlet via a second circulation water pump. The water circulation temperature control system provided by the present invention ensures fixtures are maintained at a constant temperature, thereby improving reliability of test results. In addition, the present invention uses a data acquisition and analysis system and a control system to achieve data acquisition and control for flow volumes and temperatures, thereby enabling automation of a control process, and guaranteeing production efficiency.
B: A cold and hot outlet water purifier, comprising: a water purification and supply device (9), a water storage tank (2), a water outlet temperature adjusting device and a control board; the water purification and supply device (9) comprises a water inlet pipe (10) and an reverse osmosis filter (92); the reverse osmosis filter (92) is provided with a water inlet opening, a pure water outlet opening and a waste water outlet opening, wherein the pure water inlet opening is in communication with the water storage tank (2); the water outlet temperature adjusting device comprises a rapid water heater (5); the water inlet opening is connected to the water inlet pipe (10) by means of a water inlet valve (94); the water storage tank (2) is connected to the water outlet temperature adjusting device by means of a water pump (4); the waste water opening is connected to a waste water valve (96); a water level sensor (1) for detecting the water level of the water storage tank is arranged on a water passage which is in communication with the water storage tank (2); the water inlet valve (94), the outlet water temperature adjusting device, the water pump (4), the waste water valve (96) and the water level sensor (1) are respectively electrically connected to the control board. Also disclosed is a control method for the cold and hot outlet water purifier. The cold and hot outlet water purifier may be combined with the water pump (4) and a flow control valve (8) to control the flow rate of water, resulting in improved heat conversion efficiency, allowing the entire heating device to quickly heat up, and achieving the aim of instant outputting boiling water.
C: A mobile shower apparatus comprises a seat (4), a water tank (2), a water tank cover (1), a water supply hose (11), a showerhead (12), a power source and a main control device (7). A water pump (8) is provided within the seat (4). A heat disc (3) is provided within the water tank (2). A control cover (15) is arranged on the water tank cover (1). The main control device (7) comprises a relay (18) and a step-down circuit. An operation panel (14), a shower key (13), a thermosensitive temperature probe (9) and a water level detector (10) are connected to the main control device (7). The operation panel (14) and the shower key (13) are arranged on the control cover (15). The water pump (8) is connected to the main control device (7). The mobile shower apparatus meets a shower requirement of people where the infrastructures are deficient in a more convenient and quick way by an intellectual operation mode.
D: A water saving apparatus for use in an agricultural apparatus. The water saving apparatus comprises a water collecting box (1), wherein a filter plate (3) is arranged in the water collecting box (1); the filter plate (3) is obliquely arranged; a waterproof control box (6) is arranged on a side of the water collecting box (1); a water pump (7) is arranged in the waterproof control box (6); a communication pipe (8) is connected between a water inlet of the water pump (7) and the water collecting box (1); a water supply pipe (9) is connected to a water outlet of the water pump (7); a cylinder (10) is in communication with the water supply pipe (9); the cylinder (10) is fixedly connected to a side of the waterproof control box (6); a circular shaft (11) is vertically rotationally mounted inside the cylinder (10); a spiral blade (12) is fixedly mounted on an outer side of the circular shaft (11); and a back-and-forth structure is arranged at the top of the circular shaft (11). The water saving apparatus is easy to operate, can carry out sprinkler irrigation on a whole area, can be automatically controlled, can collect and utilize rainwater, and can save water resources. In addition, further disclosed is a usage method for the water saving apparatus.
Answer: D