SU1619070A1 - Device for measuring temperature of revolving objects - Google Patents

Abstract

The invention relates to thermometry and makes it possible to improve the accuracy of measuring the temperature of rotating objects by increasing the noise immunity. On the rotating dielectric disk 1, additional coils 3 are placed, each of which is connected in series with a respective thermal converter and a transmitting coil. The receiving and compensating coils 5 and 8 are mounted on a fixed base and spaced so that their fields do not affect each other. The generator 9 produces a linearly increasing current. The synchronization unit 10 fixes the moment of current compensation. The magnitude of the current generator 9 at the time of compensation is proportional to the temperature. 4 il. i

Description

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The invention relates to a measurement technique, in particular, to devices for measuring the temperature of rotating objects by means of low constant voltage sensors and contactless induction type current collectors.

The purpose of the invention is to improve the measurement accuracy by increasing the noise immunity.

Figure 1 is a schematic diagram of the device; Fig. 2 shows the layout of the device elements; on fig.Z - version of the design of the compensation coil; figure 4 is a temporary diagram of the operation of the device.

The device (Figs. 1, 2) contains a dielectric disk 1 which is attached to a rotating object. On the disk, the transmitting coils 2.1, ..., 2.1, ..., 2.n are installed uniformly around the circumference of the radius RI by the number of sensors. Additional coils 3.1, ..., 3.1, ..., 3.p are located around a circle of smaller radius R2 in the middle between transmitters. Each pair of coils (for example, coils 2.1 and 3.1) is connected in series with each other and connected to the corresponding sensor 4.1 (thermal converter). A receiving coil with two sections 5.1 and 5.2 of the winding is mounted on a fixed base (stator). The windings of the receiving coil are made on the magnetic core 6 and are installed symmetrically on both sides of the dielectric disk 1 coaxially with the transmitting coil 2.1. The windings of the receiving coil 5.1, 5.2 are electrically interconnected according to and connected to the measuring device 7. On the same stationary stator a compensation coil is installed from two sections 8.1, 8.2, which are also electrically interconnected according to each other, arranged symmetrically on both sides of dielectric disk and connected to the generator 9 of the linearly increasing current.

The shape of the compensation coil is such that its coils are located along the line formed by the centers of the rotating additional coils (Fig. 2, 3), h. The length of the compensation coil and, consequently, the length of its coil is four to five diameters. .

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Receiving and compensating coils are installed so that when the coil

2.1 is located coaxially with the receiving coil 5, the axis of the additional coil 3.1 coincides with the center of the compensation coil 8 (figure 2). To eliminate the mutual influence of coils 5 and 8, they are spaced apart, so an additional coil 3.1 is located, for example, between transmitting coils 2.1-1 and 2., as shown in Fig. 2, when rotating the disk in the direction of the arrow. If necessary, an additional coil 3.1 can be located between the receiving 2.1-2 and 2.1-3 or even on the diametrically opposite part of the disk. On the circumference of the radius E.I in the middle between the rotating coils, the synchro-holes 11.1, ..., 11.1, ..., 11n are made. The synchronization hole 11.1 is on the continuation of the beam, the connection of the mother-in-axis of rotation of the disk 1 and the axis of the additional coil 3.1.

The synchronization unit is mounted on a stationary stator and consists, for example, of two parts: a source of 10.1 light and a photodetector 10.2. A source

10.1 light is installed above the transmitting coil 2.1-1, and the photodetector 10.2- under this coil so that through the corresponding hole 11.1 the light from the source 10.1 enters the receiver

10.2 when coil 2.1 is

at a distance of 1/2 (Fig. 2) from the receiving coil 5, and the auxiliary coil 3.1 enters the zone of action of the floor of the compensation coil 8. The output of the synchronization unit is connected to the control input of the generator 9.

The description of the operation of the device is given on the example of the 1st channel. The emf of a thermocouple (thermocouple) causes a constant current in the circuit of series-connected coils 2.1 and 3.1. This current excites a magnetic field in the coils, which induces in the receiving coil 5 a two-pole EMF pulse (Fig. 4a) when the transmitting coil passes between sections 5.1 and 5.2 of the receiving coil. The pulse amplitude is controlled by the measuring device 7. The resetting and starting of the generator 9 linearly increasing current occurs by sync pulses (CI) (Fig. 4b), which are generated by the synchronization unit 10 when the synchronous opening passes between the source 10.1 of the light and the photo-receiver 10.2. The generator 9 produces a linearly increasing current (figv) during the time interval Ј. During this time, the additional coil 3.1 is in the area of the floor of the compensation coil 8. Since the turns of the compensation coil are laid along the circumference line formed by the centers of the additional rotating coils, the magnetic field between sections 8.1, 8.2 is uniform. When a linearly increasing current is applied to the compensation coil, the field between sections 8.1, 8.2 is uniform linearly increasing.

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With a sufficient length of turns of the compensation coil, the compensating field in the interval Ј does not depend on the speed of rotation of the disk 1. In the additional coil 3. i, a constant EMF is induced, which is subtracted by the sensor's EMF 4.1. Therefore, a signal will be induced in the receiving coil 5 (FIG. 4a), the amplitude of which is proportional to the difference in the EMF of the sensor and the EMF induced by the compensation coil. When these EMFs are equal, their compensation is achieved, the amplitude of the signal in the receiving coil is zero. According to the rate of increase of the current of the generator 9, when the compensation is reached, the EMF of the sensor is judged.

The device has a high noise immunity due to the use of a receiving coil made on the magnetic core and spacing of the receiving and compensation coils in space.

Claims (1)

The invention The device for measuring the temperature of rotating objects, containing a dielectric disk located on the shaft of a rotating object with evenly distributed on one circumference of the transmitting coils to which thermal converters are connected, two in series United sections of the fixed receiving coil, installed symmetrically on both sides of the plane of rotation of the transmitting coils, coaxially with one of them, and connected to the measuring device; that, in order to improve the measurement accuracy, additional coils were introduced into it according to the number of thermal converters, located on a dielectric disk on one circumference of a smaller radius than the transmitting coils, the magnetic circuit on which the fixed receiving coil is placed, a linearly increasing current generator connected in series with the compensation coil, and a synchronization unit, you:; one connected to the control input of the linearly increasing generator current, with each additional coil connected in series with the respective transmitting coil and thermal converter and installed midway between adjacent transmitting coils, and the axis of symmetry of one of the additional coils and turns of sections of the compensation coil intersect at the center of the turns of the latter. a SI.1 at Fig.Z SYN