SU1543249A1 - Device for measuring temperature variation rate - Google Patents

Abstract

The invention relates to a measurement technique and can be used in studies and measurements of thermophysical processes, in particular their transient conditions. The purpose of the invention is to increase the noise immunity from mechanical effects of the environment. The device consists of a hermetic body 1, in the internal cavity of which a porous partition 2 is placed, dividing the cavity into two parts. The internal cavity is filled with a polar liquid. The end surfaces of the porous septum 2 are fixed with current collecting electrodes 3. In one of the parts of the cavity of the housing 1, an elastic expansion element is installed, made for example in the form of a bimetallic membrane 4 playing the role of a temperature-sensitive element. Due to the fact that the membrane 4, which is sensitive to changes in external influences, is placed inside a closed, completely filled with liquid cavity in the housing, vibrations and acoustic signals do not act on it, but close on the housing. 1 hp f-ly, 2 ill.

Description

The device relates to a measurement technique and can be used in studies and measurements of thermophysical processes, in particular their transient conditions.

The aim of the invention is to increase the noise immunity from mechanical environmental influences, in particular vibrations, linear accelerations and acoustic signals, as well as to expand the functional capabilities, which include the ability to measure another parameter — temperature.

FIG. 1 schematically shows the proposed device, a longitudinal section; in fig. 2 - device with a membrane strain gauge.

The device consists of a hermetic body 1, in the internal cavity of which a porous partition 2 is placed, dividing the cavity into two parts. The internal cavity is filled with a polar liquid. On the end surfaces of the porous partition 2, current collector electrodes 3 are fixed. In one of the parts of the housing cavity, 1, an elastic expansion element is installed, for example, in the form of a bimetallic membrane playing a role and a temperature-sensitive element. A bellows can also be used as an elastic expansion element.

The bimetallic membrane k additionally separates the part of the cavity of the housing 1, the part of the cavity 5 formed by the housing and the membrane 4 communicating hydraulically through the channel 6 with the part of the cavity 7 located behind the porous partition 2. The electrical insulation of the electrodes 3 from the housing 1 is carried out by an insulating sleeve eight.

A bimetallic sleeve 9 is used as a thermosensitive element (Fig. 2), which changes its linear dimension under the influence of temperature in the axial direction, fixed by one end on the housing, and the other on the membrane 10 (here it plays the role of only the expansion element). With the membrane 10 is in contact with the actuator 11 of the meter 12 its defamation. As the sensor-meter 12 deformation can be used sensors capacitive, inductive, mechanical, etc. types.

The device works as follows.

In the process of changing temperature

environment (growth or fall), the bimetallic membrane begins to bend in one direction or another, and part of the polar liquid in the internal cavity of housing 1 will begin to flow through porous septum 2. A potential difference appears on the end surfaces of the septum 2, due to the electrokinetic effect of the flow of a polar liquid. This potential difference is taken with the help of current-collecting electrodes 3 and is applied to a signal amplifying and processing equipment (not shown). Direction

0 liquid overflows determine the signs (plus and minus) on one or another electrode, and thus show an increase or decrease in temperature.

The potential difference becomes

5 to zero after the temperature change ceases, since then there will be no flow of fluid through the porous partition (the velocity is zero).

Channel 6 in housing 1 is designed to accommodate changes in fluid volumes in cavities 5 and 7 during membrane deflection b.

Due to the fact that the membrane kt is an element that is sensitive to changes in external influences (temperature, vibrations, acoustic signals), is placed inside a closed body cavity completely filled with liquid, then the vibrations and acoustic signals do not act on it, on the case. Thus, the immunity of the device to mechanical factors is achieved.

In addition to measuring the rate of change in temperature, the measurement of the absolute value of the temperature is carried out by the device shown in FIG. 2. Here, the deflection of the membrane 10 by means of the actuator 11 and the meter 12 fixed at each time point allows the registration of its value and, therefore, the temperature also after the end of the temperature variation process. So

5, it is possible to measure not only the rate of change of temperature, but also its absolute value.

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Claims (2)

1. A device for measuring the rate of temperature change, comprising a housing with an internal sealed cavity filled with a polar liquid and a porous partition divided into two parts, at the ends of which current-collecting electrodes, temperature-sensitive and resilient expansion elements are installed, characterized in that noise immunity, one of the parts of the body cavity is divided B32b6 an elastic expansion element, which is simultaneously a temperature-sensitive element and is made in the form of a bimetallic membrane, with the part of the cavity formed by the walls of the housing and the elastic expansion element hydraulically connected to the part of the cavity located behind the porous partition. 2. A device according to claim 1, which is equipped with a device for measuring deformations associated with an elastic expansion element. 70 / / 2