“transducer”的概念、定义、翻译、参考文献-科学参考

transducer

Physics

A device for converting a nonelectrical signal, such as sound, light, heat, etc., into an electrical signal, or vice versa. Thus microphones and loudspeakers are electroacoustic transducers. An active transducer is one that can itself introduce a power gain and has its own power source. A passive transducer has no power source other than the actuating signal and cannot introduce gain.

Chemical Engineering

A device used to convert a signal from a sensed process variable into another form of signal. Sensed variables may be temperature and pressure, and converted to pneumatic pressure, voltage, or current. These signals are then used either directly to control valves or used by computers where the signals are digitized and used with other signals to control a process or system. An I/P transducer is a type of transducer that converts an electrical input signal to a pneumatic output signal while a P/I transducer converts a pneumatic output signal to an electrical input signal. The electrical signal is in the range 4 to 20 milliamps, while the pneumatic signal is 3 to 15 psig (20–100 kPa).

Computer

1. (sensor) Any device that converts energy in the form of sound, light, pressure, etc., into an equivalent electrical signal, or vice versa. For example, a semiconductor laser converts electrical energy into light, and a piezoelectric device converts mechanical stress into electrical energy (and vice versa).
2. In formal language theory, any automaton that produces output.

Electronics and Electrical Engineering

Any device that converts a nonelectrical parameter, e.g. sound, pressure, or light, into electrical signals or vice versa. The variations in the electrical signal parameter are a function of the input parameter. Transducers are used in a wide range of measuring instruments and have a variety of uses in the electroacoustic field. Gramophone pick-ups, microphones, and loudspeakers are all electroacoustic transducers. The term is also applied to a device in which both the input and output are electrical signals. Such a device is known as an electric transducer.
The physical quantity measured by the transducer is the measurand. The portion of the transducer in which the output originates is the transduction element. The device in the transducer that responds directly to the measurand is the sensing element and the upper and lower limits of the measurand value for which the transducer provides a useful output is the dynamic range.
Several basic transduction elements can be used in transducers for different measurands. They include capacitive, electromagnetic, electromechanical, inductive, photoconductive, photovoltaic, and piezoelectric elements. Most transducers require external electrical excitation for their operation; exceptions are self-excited transducers, such as piezoelectric crystals and photovoltaic and electromagnetic types.
Most transducers provide analogue output, i.e. the output is a continuous function of the measurand, but some provide digital output in the form of discrete values. Most transducers are linear transducers, i.e. they are designed to provide an output that is a linear function of the measurand since this allows easier data handling. If the measurand varies over a stated frequency range the output of the transducer varies with frequency. The frequency response of the transducer is the change with frequency of the output to measurand amplitude ratio. The portion of the response curve over which attenuation of the measurand is significant is the rejection band of the transducer.
Like many networks transducers may be considered as two-port devices but one pair of terminals is not necessarily electrical. A symmetric transducer is one in which the input terminals and output terminals may each be simultaneously reversed without affecting the operation of the device; otherwise it is asymmetric. A transducer that operates in one direction only is a unilateral transducer; otherwise it is bilateral. If the energy loss in a bilateral transducer is the same for both directions of operation, it is a reversible transducer.
An active transducer is one that introduces gain, i.e. it derives energy from a source that is independent of the input signal energy (see active sensor). The transducer gain is defined as the ratio of the energy delivered to a suitable predetermined load to the available power at the input. In the case of a passive transducer, in which no gain is introduced, the loss is defined as the ratio of the available power at the input to the power delivered to the load under specified operating conditions (see passive sensor).

单词	transducer
释义	transducer Physics A device for converting a nonelectrical signal, such as sound, light, heat, etc., into an electrical signal, or vice versa. Thus microphones and loudspeakers are electroacoustic transducers. An active transducer is one that can itself introduce a power gain and has its own power source. A passive transducer has no power source other than the actuating signal and cannot introduce gain. Chemical Engineering A device used to convert a signal from a sensed process variable into another form of signal. Sensed variables may be temperature and pressure, and converted to pneumatic pressure, voltage, or current. These signals are then used either directly to control valves or used by computers where the signals are digitized and used with other signals to control a process or system. An I/P transducer is a type of transducer that converts an electrical input signal to a pneumatic output signal while a P/I transducer converts a pneumatic output signal to an electrical input signal. The electrical signal is in the range 4 to 20 milliamps, while the pneumatic signal is 3 to 15 psig (20–100 kPa). Computer 1. (sensor) Any device that converts energy in the form of sound, light, pressure, etc., into an equivalent electrical signal, or vice versa. For example, a semiconductor laser converts electrical energy into light, and a piezoelectric device converts mechanical stress into electrical energy (and vice versa). 2. In formal language theory, any automaton that produces output. Electronics and Electrical Engineering Any device that converts a nonelectrical parameter, e.g. sound, pressure, or light, into electrical signals or vice versa. The variations in the electrical signal parameter are a function of the input parameter. Transducers are used in a wide range of measuring instruments and have a variety of uses in the electroacoustic field. Gramophone pick-ups, microphones, and loudspeakers are all electroacoustic transducers. The term is also applied to a device in which both the input and output are electrical signals. Such a device is known as an electric transducer. The physical quantity measured by the transducer is the measurand. The portion of the transducer in which the output originates is the transduction element. The device in the transducer that responds directly to the measurand is the sensing element and the upper and lower limits of the measurand value for which the transducer provides a useful output is the dynamic range. Several basic transduction elements can be used in transducers for different measurands. They include capacitive, electromagnetic, electromechanical, inductive, photoconductive, photovoltaic, and piezoelectric elements. Most transducers require external electrical excitation for their operation; exceptions are self-excited transducers, such as piezoelectric crystals and photovoltaic and electromagnetic types. Most transducers provide analogue output, i.e. the output is a continuous function of the measurand, but some provide digital output in the form of discrete values. Most transducers are linear transducers, i.e. they are designed to provide an output that is a linear function of the measurand since this allows easier data handling. If the measurand varies over a stated frequency range the output of the transducer varies with frequency. The frequency response of the transducer is the change with frequency of the output to measurand amplitude ratio. The portion of the response curve over which attenuation of the measurand is significant is the rejection band of the transducer. Like many networks transducers may be considered as two-port devices but one pair of terminals is not necessarily electrical. A symmetric transducer is one in which the input terminals and output terminals may each be simultaneously reversed without affecting the operation of the device; otherwise it is asymmetric. A transducer that operates in one direction only is a unilateral transducer; otherwise it is bilateral. If the energy loss in a bilateral transducer is the same for both directions of operation, it is a reversible transducer. An active transducer is one that introduces gain, i.e. it derives energy from a source that is independent of the input signal energy (see active sensor). The transducer gain is defined as the ratio of the energy delivered to a suitable predetermined load to the available power at the input. In the case of a passive transducer, in which no gain is introduced, the loss is defined as the ratio of the available power at the input to the power delivered to the load under specified operating conditions (see passive sensor).
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