SU832362A1 - Magnetoelastic force transducer - Google Patents

Description

(54) MAGNETIC ELASTIC CONVERTER EFFORTS

The invention relates to a technique for measuring forces, namely to converters based on a change in the magnetic properties of a material as a function of the load. Magnetoelastic force transducers are known, in which the supply and measuring windings are placed on additional U-shaped magnetic cores inserted diagonally into the openings of the loaded magnetic circuit 1 However, in these converters, a part of the magnetic circuit is used that is enclosed between the holes, the resulting sensitivity of the transducer is low .. Also known are magnetoelastic transducers, which are a cantilever structure, including a base made of a nonmagnetic alloy, and The present hundred of two detachable parts. Plates of ferromagnetic material are fixed on one side of not every half of the base. On the other side are protrusions intended to be joined with protrusions of the second half. Along the base, as in the plates, there is a window for placing the winding (between the projections). One of the ends of the structure is fixed, and attaches to the second. with measured force. Under the influence of the latter, a tensile stress arises in the upper plate pack, and a compressive stress in the lower one. However, the use of non-ferromagnetic bases reduces the sensitivity of the transducer, since the mechanical stresses arising at the bases are not used to isolate the useful signal. The purpose of the invention is to increase the sensitivity. This goal is achieved by the fact that the window of each plate of the magnetic circuit is divided into two equal parts by a jumper, while the adjacent magnetic core plates are vibrantly perpendicular, and a non-ferromagnetic spleen / ieHT is installed between them. Figure 1 and 2 presents the design. converter qi without windings in two projections; in fig. 3 - converter with windings, general view; in fig. 4 shows a replacement circuit for a converter magnetic circuit.

The converter contains a jumper of magnetic conductor 1 nd 2, bases 3, a non-ferromagnetic element between VALVES 4, a window 5-, holes b for fastening a package of mehredu base, magnetized windings 7 and measuring windings 8, windings 9. The windings are connected in pairs differential transport scheme

FIG. 4 - Rf, - magnetic resistances of the sections of the magnetic circuit between the ends of the perpendicular strings; R and. - magnetic resistances of rods; - magnetomotive magnetizing windings; f is the current through the magnetize windings; W is the number of turns.

The Converter operates as follows.

When measured, the magnetic resistances of the rods are Rm K | L2. and, as a result of the symmetry of the circuit, the magnetically moving forces of the melody by the points a, b, c, and d are zero. (f} 4a5 V ed 0). Therefore, the magnetic flux flows through the circuit cbR ,, da. Through the sections of ab and cd, the flow is not closed, the voltage measurements at the outputs of the windings are zero (test, y 0). When, under the action of force P, rod 1 is expanded, rod 2 is compressed, as a result of which R | rt- decreases, and

1 is magnified 1, the magnetic field of the magnetic circuit is disturbed (““ # K ”,.) the magnetic flux closes through the magnetic sections of the measuring windings (ab and cd), and in these windings receive a voltage proportional to the force P.

Claims (2)

1. USSR author's certificate If 240303, class G 01 L 1/12, 11/23/68. 2. Theses of reports of All-Union conferences on information-measuring systems IIS-77, p. 162 (prototype).  ; FIG. 2 g 6   II I