Abstract:
A gas/liquid separation device is connected to a discharge valve which can discharge fuel gas to the outside of a fuel cell system along with water accumulated in the gas/liquid separation device. A change in pressure at a portion upstream of the discharge valve, which occurs due to an opening operation of the discharge valve, is detected or estimated, and an integral value is obtained by integrating the amount of change in the pressure with respect to time from when the discharge valve is opened or a parameter value corresponding to the integral value is obtained. The integral value represents an amount of fuel gas discharged due to the opening operation of the discharge valve. It is therefore possible to reliably discharge a desired amount of fuel gas by deciding a closing time at which the discharge valve is closed based on the integral value or the parameter value corresponding to the integral value.
Abstract:
A standoff control method and apparatus for a plasma cutting machine, which can quickly correct deviation of standoff from a set value, can keep constant standoff with respect to the change of a cutting speed, does not cause the drop of working efficiency even at the time of occurence of double-arc and can accurately detect the use limit of an electrode. A standoff correction computing device (28) includes a reference voltage computation setter (36) for outputting a reference voltage between an electrode or nozzle and a work to be cut with respect to predetermined standoff, an error computing device (37) for calculating the error of the detected voltage from the reference voltage and a correction quantity computing device (38) for outputting an elevation speed signal of a torch in accordance with this error. The computing device (28) may further include an electrode consumption/standoff detector (34) for outputting a standoff signal compensating for the voltage rise component based on the consumption of the electrode to the error computing device (37).
Abstract:
A gas/liquid separation device is connected to a discharge valve which can discharge fuel gas to the outside of a fuel cell system along with water accumulated in the gas/liquid separation device. A change in pressure at a portion upstream of the discharge valve, which occurs due to an opening operation of the discharge valve, is detected or estimated, and an integral value is obtained by integrating the amount of change in the pressure with respect to time from when the discharge valve is opened or a parameter value corresponding to the integral value is obtained. The integral value represents an amount of fuel gas discharged due to the opening operation of the discharge valve. It is therefore possible to reliably discharge a desired amount of fuel gas by deciding a closing time at which the discharge valve is closed based on the integral value or the parameter value corresponding to the integral value.
Abstract:
The invention provides a plasma cutting method and a cutting apparatus, which can be switched between suitable flow rates of a protective gas at the time of piercing and cutting to further produce suitable composition of the protective gas at the time of piercing and cutting, so that it is possible to protect a nozzle favorably from dross and the like, provide cutting faces of high quality and reduce a running cost of the protective gas. Thus, a device (27, 40) for detecting completion of piercing is provided which detects an electric current passing between an electrode (1) and a stock (31) being cut at the time of piercing and outputs a piercing completion signal, and a flow regulator (15) is provided which is disposed in a circuit for the protective gas and switches in response to a signal of completion of piercing a flow rate of the protective gas from that at the time of piercing to that at the time of cutting. In addition, on-off valves (51, 53) are provided in the circuit for the protective gas for switching a composition of the protective gas between those at the time of piercing and cutting.
Abstract:
A gas/liquid separation device is connected to a discharge valve which can discharge fuel gas to the outside of a fuel cell system along with water accumulated in the gas/liquid separation device. A change in pressure at a portion upstream of the discharge valve, which occurs due to an opening operation of the discharge valve, is detected or estimated, and an integral value is obtained by integrating the amount of change in the pressure with respect to time from when the discharge valve is opened or a parameter value corresponding to the integral value is obtained. The integral value represents an amount of fuel gas discharged due to the opening operation of the discharge valve. It is therefore possible to reliably discharge a desired amount of fuel gas by deciding a closing time at which the discharge valve is closed based on the integral value or the parameter value corresponding to the integral value.
Abstract:
A method and an apparatus for plasma cutting wich can produce a cut product having less dross affixed thereto and a clear cut surface and which is capable of high-speed cutting even at the time of piercing. Due to this, at the time of piercing oxidizable gas (O2) is used as plasma gas and at the time of cutting non-oxidizable gas (N2) is used as plasma gas to cut a material (6) to be cut. In addition, when shifting from piercing to cutting the supply of non oxydizable gas (N2) may be started before the supply of oxydizable gas (O2) is stopped.