초록 ▼

Vacuum monitoring apparatus which includes a control circuit having transducer means for sensing the vacuum levels in a system and generating output signals. The control circuit includes adjustment circuits which compare the transducer output with selectively variable reference signals for controlli

Vacuum monitoring apparatus which includes a control circuit having transducer means for sensing the vacuum levels in a system and generating output signals. The control circuit includes adjustment circuits which compare the transducer output with selectively variable reference signals for controlling indicator devices and an alarm circuit when the vacuum levels are at respective high, low and normal settings. An off adjustment circuit is provided for setting the vacuum level below which the alarm circuit is disabled. A time delay circuit disables the alarm circuit for a predetermined time delay to provide for measurement of the vacuum recovery rate for the system.

대표청구항 ▼

Apparatus for monitoring vacuum conditions in a system employing vacuum, comprising the combination a control circuit including transducer means for sensing the level of the vacuum at a given location in the system and generating an output signal which is a function of the sensed level, a high vacuu

Apparatus for monitoring vacuum conditions in a system employing vacuum, comprising the combination a control circuit including transducer means for sensing the level of the vacuum at a given location in the system and generating an output signal which is a function of the sensed level, a high vacuum level adjustment circuit for selectively establishing a first reference signal which is a function of a predetermined upper limit of vacuum in the system, a low vacuum level adjustment circuit for selectively establishing a second reference signal which is a function of a predetermined lower limit of vacuum in the system, comparator circuit means for comparing the output signal with the first and second reference signals, said comparator circuit means establishing a first control signal responsive to a predetermined relation between the output signal and first reference signal, said comparator circuit further establishing a second control signal responsive to a predetermined relation between the output signal and second reference signal, and indicator circuit means for signaling a high vacuum condition responsive to the first control signal and for signaling a low vacuum condition responsive to the second control signal.