SU853616A1 - Switching device - Google Patents

Description

(54) SWITCHING DEVICE

The invention relates to devices for control, working with contact sensors sensitive to the effects of physical quantities, in particular to temperature, pressure, displacement regulators, working in systems that require high reliability and low power consumption. A contact temperature controller is known, containing fixed change-over sensitive contact, heat sensitive element, feedback electromagnet, spark-arresting device, relay wuxi rer, a motor with potentiometer feedback 1. However, this device is not sufficiently reliable, because the relay coil of the electromagnet and is permanently under tension. It is also known a device for controlling technological parameters 2, which contains a contact sensitive element, a power source, a first key transistor, to the collector of which one of the terminals of the first winding of a switch is connected. This device is also not sufficiently reliable due to the presence of “bounce of contacts of a remote switch. Closest to the invention is a device for controlling technological parameters 3, which contains a contact sensing element, a power source, transistors, resistors and a remote switch with two windings. The disadvantage of the prototype is that the device has a hysteresis, which is determined by the movement of the moving contact of the sensitive element from one fixed contact to another. The transition time is determined by the constant time of the object and the most sensitive element, which may be insignificant. The aim of the invention is to increase the accuracy of work. The goal is achieved by the switching device containing a two-winding remote switch, the windings of which are connected to the first pole of the power source and through a series-connected contact sensing element and the first resistor to the base of the first key transistor and the first fixed contact of the remote switch, the second fixed contact of which is connected with the base of the second key transistor and through the second resistor with the first pole of the power source, which the second pole of which connects the moving contact of the remote switch and the emitters of the first and second key transistors, the collectors connected to the other leads of the windings of the remote switch, contains a third resistor and a third key transistor, the base of which is connected to the first pole of the power source through series-connected, emitter - with emitters of the first and second key transistors, and the collector - with the base of the second key transistor.

Diagram of the device shown in the drawing.

The switching device contains a contact sensitive element 1, which is made with one closing contact, the first and second key transistors 2, 3, respectively, with the second and third resistors 4, 5, two-winding remote switch 6 with windings 7, 8 and switching contact 9 with moving 10 and fixed 11, 12 pins and a power source 13. In addition, the device contains a third key transistor 14 and a third resistor 15.

The device works as follows.

In the initial state shown in the drawing, the contact sensor is in a position that corresponds to an open contact. In this case, the heat transfer device is in a stable state in which the key transistors 2, 3, 14 are closed.

When the contact of the sensitive element closes under the action of the external environment, transistor 14 will open through resistor 15 and will maintain key transistor 3 in the closed state. In addition, through the resistor 4, the transistor 2 opens, the switch 6 operates through the winding 7 and the moving contact Yu, opens the base of the third key transistor 3 and connects the base of the second key transistor 2 to the second pole of the power source 13. The first key transistor 2 closes and the second key transistor 3 will remain in the closed state as the third key transistor 14 is open. Thus, in this state of the device, the first and second key transistors 2, 3 are closed.

When the contact of the sensing element 1 is opened under the action of the external medium, the third key transistor 14 closes. This will open the second key transistor 3 and the double-winding will operate

the remote switch 6 (winding 8) and the moving contact 10 will open the base of the first key transistor 2 and close the base of the second key transistor 3 with the second pole of the power source 13. the second key transistor 3 closes. So, the device returned to its original state, in which all transistors are closed. The invention allows to obtain a positive effect, i.e. eliminate hysteresis, extend functionality

devices and improve accuracy.

Claims (3)

Invention Formula A switching device containing a two-winding remote switch, the windings of which are connected to the first pole of the power source and through a series-connected contact sensitive element and the first resistor - with the base of the first key transistor and the first fixed contact of the remote switch, the second fixed contact of which is connected to the base of the second key transistor and through the second resistor to the first pole of the power supply, to the second pole of which the movable contact of the remote switch and the first and second emitters are connected key transistors, collectors connected to other terminals of the remote switch switches, characterized in that, in order to increase the accuracy of The device bots, it contains the third resistor and the third key transistor, the base of which is connected through the third resistor and the contact element to the first pole of the power source, the emitter to the emitters of the first and second key transistors, and the collector to the base of the second key transistor. Sources of information taken into account during the examination 1. N. Grischanov. High-rise equipment of civil aviation aircraft. M., “Energie, 1971, p. 125, fig. 6.10. 2. USSR author's certificate No. 435507, cl. G 05 D 23/19, 1970. 3. USSR author's certificate No. 596923, cl. G 05 D 23/19, 1978 (prototype).