SU1002823A1

SU1002823A1 - Inductive displacement pickup

Info

Publication number: SU1002823A1
Application number: SU813357215A
Authority: SU
Inventors: Владимир Викторович Ковалевский; Алексей Васильевич Федотов
Original assignee: Омский политехнический институт
Priority date: 1981-11-26
Filing date: 1981-11-26
Publication date: 1983-03-07

Description

(5) ИНДУКТИВНЫЙ ДАТЧИК ПЕРЕМЕЩЕНИЙ(5) INDUCTIVE DISPLACEMENT SENSOR

Изобретение oTHocMtcH к измерительной технике и может быть использовано дл контрол размеров деталей.The invention oTHocMtcH to measurement technology and can be used to control the dimensions of parts.

Известен индуктивный датчик перемещений , содержащий катушку индуктивности , магнитопровод, подвижный корь и бифил рную обмотку l ,An inductive displacement sensor is known, comprising an inductance coil, a magnetic core, movable measles, and a bifillary winding l,

Недостатком его вл етс отсутствие компенсации температурной нестабильности магнитной проницаемости материала магнитопровода и вследствие этого низка точность.Its disadvantage is the lack of compensation for the temperature instability of the magnetic permeability of the magnetic material and, consequently, low accuracy.

Наиболее близким к изобретзнию вл етс индуктивный датчик перемещений , содержащий корь, св зываемый в процессе измерени с контролируемым объектом, магнитопровод,и размещенную в нем катушку индуктивности 2 .Closest to the invention, there is an inductive displacement transducer containing measles, connected in the measurement process with the object being monitored, a magnetic core, and an inductor 2 located therein.

Недостатком известного датчика вл етс значительна погрешность, обусловленна изменением магнитной проницаемости материала магнитопровода при изменении температуры окру жакхцей среды.A disadvantage of the known sensor is a significant error due to a change in the magnetic permeability of the magnetic core material with a change in the temperature of the surrounding medium.

Цель изобретени - уменьшение температурной погрешности индуктивного датчика перемещенийТThe purpose of the invention is to reduce the temperature error of the inductive displacement transducer T

Указанна цель достигаетс тем, что индуктивный датчик перемещений, содержащий корь, св зываекый в процессе измерени с контролируемым This goal is achieved by the fact that an inductive displacement transducer, containing measles, is associated in the measurement process with a controlled

,д объектом, магнитопровод и размещенную в нем катушку индуктивности, снабжен упругим элементом, охватывающим с нат гом магнитопровод, выполненный из магнитоупругого материалаThe object, the magnetic core and the inductance coil placed in it, is provided with an elastic element, which covers the magnetic core made of a magnetoelastic material.

J5 с коэффициентом магнитоупругости , равнымJ5 with a magnetoelasticity coefficient equal to

А.- У ,A.- Y,

Кд1доб-ьбо Cd1dob

Claims

20 A Aoi are the temperature coefficients of linear expansion of the materials of the magnetic circuit and the elastic element, respectively; 3 y is the temperature coefficient of magnetic permeability of the material of the magnetic circuit; the initial mechanical stress in the material of the magnetic circuit; Db is the ambient temperature range; coefficient taking into account the design parameters. The drawing shows schematically a variant of the sensor design with a cup-shaped magnetic core and an annular elastic element. The sensor contains a cup-shaped magnetic circuit 1, in the cavity of which coil 2 of inductance is placed, movable bore 3 and an annular elastic element encompassing magnetic field 1. Under the influence of an elastic element, an initial mechanical stress 6o is created in the magnetic circuit. the permeability of which depends on the magnitude of the mechanical stress in it, i.e. from a magnetoelastic material. The sensor works as follows. The movement of the monitored object is perceived by the mobile cortex 3 and leads to a change in its inductance. The inductance of the sensor is also influenced by the ambient temperature due to the temperature instability of the material of the magnetic circuit 1. For the ambient temperature range, which is usually several tens of degrees, the change in the magnetic permeability is D (U of the material of the magnetic circuit 1 is UfU / UoyAt, - the initial value the magnetic permeability of the material of the magnetic circuit. With a temperature change as a result of thermal expansion, the linear dimensions of the magnetic conductor 1 and the elastic element also change. leads to a change in the mechanical stresses in the material of the magnetic core 1 and, consequently, to a change in the magnetic permeability of the magnetoelastic material of the magnetic core by the value L U- | Uo (. 234 Since the material of the magnetic core is chosen from the condition ((1), the resulting change in its magnetic permeability under temperature and mechanical stress are mutually compensated and equal to zero, as can be seen from a comparison of expressions (2) and (3) with regard to (1). Thus, in this inductive displacement sensor, temperature stability of the magnetic permeability of the magnetic core material is provided, which reduces the temperature error of the sensor, and the design of the magnetic circuit can be different, for example, P-type or H-shaped, etc. Claims of the invention An inductive displacement transducer containing measles connected in the process of measurement with a controlled object, a magnetic core and an inductance coil located therein, characterized in that, in order to reduce its temperature error, it is provided with an elastic element encompassing the magnetic core, Made of a magnetoelastic material with a magnesity coefficient of r. equal to Kiiu (x; f6o A about - difference of temperature coefficients of linear expansion of materials of a magnetic conductor and an elastic element, respectively;; temperature coefficient of magnetic permeability of a material of a magnetic conductor; initial mechanical stress in a material of a magnetowire; - ambient temperature range; K - coefficient taking into account structural parameters. Sources of information that are considered in the examination 1. The author's certificate of the USSR, class G 01 D 5/243, 1970.

2.Agaykin D.I. and others. Sensors roll and adjustment. M., Mastroenie, 19b5, p. 105 (proto).

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