| 摘要 |
An automatic shut-off nozzle has liquid flow through its vapor return means automatically stopped when liquid has filled the vapor line sufficiently to move a first valve to block the vapor return line. This blocking of the vapor return line by the liquid increases the pressure in the tank being filled to cause stopping of liquid flow through the automatic shut-off nozzle. If the pressure in the tank increases beyond a predetermined pressure when the first valve is in its blocking position, the increased pressure is vented by a second valve, which is supported by the first valve, moving to an open position. The automatic shut-off nozzle also stops flow in response to the tank being filled to a predetermined level with liquid or to the pressure in the tank exceeding a predetermined pressure even when there is no blocking of the vapor line by the first valve. In another embodiment, a float valve activates a switch when liquid has filled the vapor line sufficiently to move the float valve with activation of the switch stopping flow of liquid to the nozzle.
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