SU369426A1 - DEVICE FOR CONTROL OF MAXIMUM TEMPERATURE - Google Patents

Description

This invention relates to the field of temperature control.

Devices are known for controlling the maximum temperature in various assemblies of mechanisms, comprising temperature-sensitive bimetallic plates with contacts fixed to them and a pointing device.

However, the known devices cannot simultaneously control the temperature at several points, since they require an external power source for the circuit, use of their own pointing device for each sensor, or use of a switch.

In the proposed device, in order to simplify the construction, the contacts are made in the form of thermocouple electrodes, which form a hot junction, connected to the circuit of the device.

In addition, to ensure simultaneous temperature control in different measurement objects using a single instrument without a switch in the thermocouple circuit, installation resistances are included to ensure that the zone of possible readings of each thermocouple is shifted on the scale of the instrument.

FIG. 1 shows a diagram of the described device with a parallel connection of thermocouple electrodes; in fig. 2 - the same with a serial connection.

Electrodes / and 2, made, for example, of chromel and copel, are attached to bimetallic plates 3 and 4 installed in insulator 5. The latter is enclosed in a ring 6 provided with a bracket 7 intended to fasten elements of a hot junction in the measurement zone.

FIG. 1, the set resistances 8 are connected in series in a chain, and in FIG. 2 - in parallel with spas. In the latter case, the number of cold junctions 9 should correspond to the number of hot junctions (sensors).

The magnitude of the resistance is selected so that when the circuit is 1 and one or several electrodes, it is possible to determine which hot junctions of the sensor are closed in terms of the value produced by the EMF. The closure of the electrodes of the gorr-chi.kh junctions of thermocouples occurs as a result of the bending of the bimetallic plates under the influence of a controlled temperature. The dimensions of bimetallic plates can be, for example, the following (in mm): length - 5, width - 2, and thickness 0.2-0.3.

The small dimensions of the sensors allow them to be installed directly behind the bearings in the flow or vapor thereof. No protective elements, such as resistance thermometers, are required.

The device for registration of emf The sensor can serve as a millivoltmeter 10, the scale of which is calibrated for the number of thermal recording elements.

The introduction of bimetallic nlastin thermocouples into a hot tube does not affect the magnitude of the emf, since the temperature of these plates and their connection points with thermoelectrodes is the same.

Subject and d on e and e

Claims (2)

1. A device for controlling the maximum temperature containing a temperature-sensitive; 1 bimetallic plates with hardened contacts and a pointing device, characterized in that, in order to simplify the design, the contacts are made in the form of thermocouple electrodes, forming a hot junction when closed; included in the circuit of the device. 2. The device according to claim 1, characterized in that, in order to enable simultaneous control of temperature in various measurement objects using a single instrument without a switch by shifting the instrument scale to the zone of possible readings of each thermocouple, installation resistances are included in the thermocouple circuit.