摘要:
In a nuclear magnetic resonance apparatus 1A including nuclear magnetic resonance means 2 for elucidating atomic configuration and molecular structure of a substance based on a decay signal of induced electromotive force caused by resonance precession of nuclear magnetic moment induced by irradiation of electromagnetic pulses in an RF region when the substance is exposed to a strong magnetic field, and a vibration isolation mechanism 3 for suppressing vibrations, the vibration isolation mechanism 3 has an air spring 11 as an actuator, the air spring being connected to a pressurized air source 34 via an electro-pneumatic converter 25 and acting to exert a force for vibration isolation on the nuclear magnetic resonance means 2, and the vibration isolation mechanism is formed so as to be capable of active vibration isolation, and disposed away from the nuclear magnetic resonance means 2 by such a distance that the electro-pneumatic converter 25 never incurs any malfunctions or operating failures under influence of a magnetic field generated by the nuclear magnetic resonance means 2.
摘要:
A nuclear magnetic resonance apparatus includes a nuclear magnetic resonance device for elucidating atomic configuration and molecular structure of a substance based on a decay signal of induced electromotive force caused by resonance precession of nuclear magnetic moment induced by irradiation of electro-magnetic pulses in an RF region when the substance is exposed to a strong magnetic field, and a vibration isolation mechanism for suppressing vibrations. The vibration isolation mechanism has, as an actuator, an air spring connected to a pressurized air source via an electro-pneumatic converter and acting to exert a force for vibration isolation on the nuclear magnetic resonance device. The vibration isolation mechanism is capable of active vibration isolation, and disposed away from the nuclear magnetic resonance device by such a distance that the electro-pneumatic converter never incurs any malfunctions or operating failures under influence of a magnetic field generated by the nuclear magnetic resonance device.
摘要:
By a controller 18 which receives signal input from a first sensor 16 for detecting the vibratory state of an object O to be isolated from vibration and from a second sensor 17 for detecting the vibratory state of an intermediate mass element 13, a signal is outputted to a power input portion 12 of a piezoelectric element 11 to cause a voltage variation such that the intermediate mass element 13 vibrates to cancel out the vibrations of the object O in an acting direction.
摘要:
A method of controlling level lateral positions of a vibration control base suspended by air springs to be returned to its standard level and lateral positions and to keep their positions by utilizing analog integration or a feedback compensation in combination thereto so as to control an air pressure or air pressures of air springs for driving the vibration control base and also controlling vertical and horizontal vibrations of the vibration control base and an apparatus for carrying out the said method.
摘要:
An active control precision damping table supported by air springs. Level displacement and vibrations of the table are detected by a sensor or sensors, and sensor outputs are fed to a variation adder which carries out an adding operation on one of the sensor outputs and an inversion signal produced by inverting the other sensor output 180 degrees. The adder outputs results of the operation to a drive circuit, which in turn outputs a drive signal to a control valve. The control valve is operable in response to the drive signal to adjust air pressure in pressure vessels of the air springs.
摘要:
An active control precision damping table supported by air springs. Level displacement and vibrations of the table are detected by a sensor or sensors, and sensor outputs are fed to a variation adder which carries out an adding operation on one of the sensor outputs and an inversion signal produced by inverting the other sensor output 180 degrees. The adder outputs results of the operation to a drive circuit, which in turn outputs a drive signal to a control valve. The control valve is operable in response to the drive signal to adjust air pressure in pressure vessels of the air springs.
摘要:
An active control precision damping table supported by air springs. Level displacement and vibrations of the table are detected by a sensor or sensors, and sensor outputs are fed to a variation adder which carries out an adding operation on one of the sensor outputs and an inversion signal produced by inverting the other sensor output 180 degrees. The adder outputs results of the operation to a drive circuit, which in turn outputs a drive signal to a control valve. The control valve is operable in response to the drive signal to adjust air pressure in pressure vessels of the air springs.
摘要:
There is provided a vibration isolator capable of, (1) vibration isolation performance for ground motion disturbance: vibration isolation for floor vibration, and (2) vibration control performance for direct acting disturbance: suppression of swing due to driving reaction force caused by stage movement, significantly improving the above (2), i.e., the vibration control performance, with keeping the above (1), i.e., the vibration isolation performance, at a high level.
摘要:
A radio-frequency signal receiver and its manufacturing method are disclosed. A tuner receives a radio-frequency signal, and a demodulator receives an output signal from the tuner. An error corrector receives an output from the demodulator. A determiner determines whether or not an error rate supplied from the error corrector is not less than a predetermined rate. A controller receives an output from the determiner, and based on the determination, the controller controls a plurality of sections forming the radio-frequency signal receiver. The controller controls selectively one of the plurality of sections, thereby lowering the error rate. A manufacturing method of this receiver makes a memory, coupled to the controller, store a shift-amount of frequency corresponding to an interference signal in a pass-band of a narrow-band filter.
摘要:
A fluid actuator applicable to high load with small space, comprising a core with an output shaft and two discs; and a cylinder casing which receives the core in a hollow, an upper end of the upper shaft projecting out of an upper opening and the core is set free. The cylinder casing includes an annular protrusion projecting into an air gap between the discs, wherein a small seal member which seals upper and lower spaces is provided between a portion of the core located between the discs and an annular protrusion and a large seal member which seals upper and lower spaces is provided between an inner peripheral surface of the cylinder casing, and an outer peripheral surface of the discs. The interior of the cylinder casing is divided into four small cavities abutting on one another vertically and an effective pressure-receiving area of the large seal member is larger than that of the small seal member to each of the small cavities.