@article{oai:soar-ir.repo.nii.ac.jp:00013086,
 author = {矢沢,  信八},
 journal = {信州大学工学部紀要},
 month = {Dec},
 note = {When one intends to measure successively displacement of a vibrating object it is apt to be affected by an external mechanical force, it is often unsuitable to use an instrument that needs contact like a strain gage, especially when the moment of inertia of the object is small. Generally one uses a displacement vibrometer utilizing variations of oscillating fequency due to the impedance in such a case. The author tried his hand at a displacement vibrometer utilizing varia tions of self inductance, and obtained a pretty satisfactory result by shaping magnetic core of its detector in a new mode. Displacement of the object is detected as a variation of oscillating frequency from 2MC, demodulated through a descriminator, amplified and measured with a voltmeter or recorded with an electro-magnetic recorder. The trial production presented principal results as follows. (1) Maximum measurable displacement is 0.6 mm. (2) It is applicable to any kind of material. The relation between input dis placement and output voltage, however, changes with variations of per meablity and conductivity of the measured object. (3) The detector performance is not affected by magnetic field from the measured object as long as its strength is below 10 gausses. (4) It is neither affected by oil and grease spattered on the detector surface nor that on the measured object surface. (5) Ferrite permeability of the detector core changes with environmental temperature. This causes pretty large variation of the detector performance. Therefore, the author recommends ferrite cores with little permeability., Article, 信州大学工学部紀要 21: 67-78 (1966)},
 pages = {67--78},
 title = {自己インダクタンス変化による変位振動計の試作：周波数変調方式による},
 volume = {21},
 year = {1966}
}