SU930623A1

SU930623A1 - Device for preventing contact bouncing effect

Info

Publication number: SU930623A1
Application number: SU803000037A
Authority: SU
Inventors: Александр Иванович Чумаков
Original assignee: Опытно-Конструкторское Бюро Приборов Контроля И Автоматики
Priority date: 1980-11-04
Filing date: 1980-11-04
Publication date: 1982-05-23

Description

Изобретение относится к автоматике и телемеханике и может быть использовано в коммутационных ιцепях управления.The invention relates to automation and telemechanics and can be used in switching control circuits.

Известно устройство, исключающее влияние дребезга от электромеханического выключателя, содержащее логические элементы, резисторы и конденсаторы И·A device is known that eliminates the effect of bounce from an electromechanical switch containing logic elements, resistors and capacitors AND

Недостаток этого устройства - невысокая достоверность кодируемой информации.The disadvantage of this device is the low reliability of the encoded information.

Наиболее близким техническим решением является устройство, содержащее механический контакт, подключенный через инвертор и элемент задержки к триггеру ^2j .The closest technical solution is a device containing a mechanical contact connected through an inverter and a delay element to a trigger ^ 2j.

Недостатком данного устройства является невысокая надежность функционирования.The disadvantage of this device is the low reliability.

Цель изобретения - повышение надежности функционирования.The purpose of the invention is to increase the reliability of operation.

Поставленная цель достигается тем, что в устройство, содержащее механи2 ческий контакт, первый вывод которого соединен с общей шиной, а второй через резистор - с шиной источника питания, * триггер и элемент задержки, введен элемент ИЛИ-HE, а элемент задержки ⁵ выполнен на RC-цепи и диоде, причем общий вывод RC-цепи соединен с первым входом триггера и через диод - с выходом элемента ИЛИ-HE, первый вход которого соединен с вторым Гвыводом ' ¹⁰ механического контакта и вторым входом триггера, а второй вход - с прямым выходом триггера, при этом другие выводы RC-цепи подключены соответствен^ но к шине источника питания и общей ^,S шине.This goal is achieved by the fact that an OR-HE element is inserted into the device containing a mechanical contact, the first output of which is connected to a common bus, and the second through a resistor to the bus of the power supply, * trigger and delay element, and delay element ^{5 is} made on An RC circuit and a diode, the common terminal of the RC circuit being connected to the first input of the trigger and through the diode to the output of the OR-HE element, the first input of which is connected to the second pin ^{10 of the} mechanical contact and the second input of the trigger, and the second input to the direct trigger output, with other output RC-circuit are connected respectively to the bus but ^ the power supply and a ^{common, S} bus.

На чертеже представлена принципиальная электрическая схема устройства, которое содержит механический контактThe drawing shows a schematic electrical diagram of a device that contains a mechanical contact

1,элемент 2 ИЛИ-HE, триггер 3, элемент 4 задержки, состоящий изрС-цепи (резистора 5, конденсатора 6) и диоде 7, резистор 8.1, element 2 OR-HE, trigger 3, delay element 4, consisting of an SRC circuit (resistor 5, capacitor 6) and diode 7, resistor 8.

Устройство работает следующим об- ⁴разом.The device operates as follows ⁴ times.

В исходном состоянии контакт 1 разомкнут, и на выходе элемента 2 ИЛИНЕ низкий уровень напряжения, опреде- 5 ляемый высоким входным потенциалом от источника питания через резистор 8.In the initial state, contact 1 is open, and at the output of element 2 it is NOT a low voltage level, determined by 5 high input potential from the power source through resistor 8.

Высокий потенциал на входе элемента ИЛИ-НЕ 2 определяет также исходное состояние триггера 3, на прямом выходе 10 которого устанавливается низкий уровень напряжения. Следовательно, конденсатор 6 R С-цепи элемента задержки 4 разряжен через, диод 7 и открытый выход элемента ИЛИ-НЕ 2. 15The high potential at the input of the OR-NOT 2 element also determines the initial state of the trigger 3, at the direct output 10 of which a low voltage level is set. Therefore, the capacitor 6 R of the C-circuit of the delay element 4 is discharged through the diode 7 and the open output of the element OR NOT 2. 15

При замыкании контакта 1 возникает дребезг, однако на выход устройства (выход триггера 3) .он не проходит из-за того, что конденсатор 6 не успевает зарядиться до уровня переключения триг- ₂₀гера 3 (постоянная времени заряда конденсатора 6 выбрана'больше времени дребезга). После прекращения дребезга, (контакт фиксированно замкнут) конденсатор 6 заряжается через резистор 5 от ₂₅источника питания и переключает триггер 3. На прямом выходе триггера 3 формируется высокий уровень напряжения, который через элемент ИЛИ—НЕ 2 быстро разряжает конденсатор 6, и на входе ₃₀триггера 3 вновь формируется низкий уровень напряжения.When contact 1 closes, a chatter occurs, but it does not pass to the device output (trigger 3 output) due to the fact that the capacitor 6 does not have time to charge to the trigger- ₂₀ switch 3 switching level (the charge time constant of capacitor 6 is selected longer than the chatter ) After the bounce stops, (the contact is fixedly closed), the capacitor 6 is charged through the resistor 5 from the ₂₅ power source and switches the trigger 3. A high voltage level is formed at the direct output of the trigger 3, which quickly discharges the capacitor 6 through the OR — NOT 2 element, and at the input ₃₀ trigger 3 again forms a low voltage level.

При размыкании контакта 1 устройство возвращается в исходное состояние с приходом первого положительного всплеска напряжения дребезга, который формируется на входе триггера 3 от источника питания через резистор 8. Последующие всплески напряжения дребезга на работу устройства никакого воздействия не ока зывают, так как постоянная времени-заряда конденсатора 6 больше времени дребезга. Следовательно устройство практически не имеет временной задержки при размыкании контакта.When contact 1 opens, the device returns to its initial state with the arrival of the first positive surge of bounce voltage, which is formed at the input of trigger 3 from the power source through resistor 8. Subsequent surges of the bounce voltage on the device do not have any effect, since the time-charge constant of the capacitor 6 more bounce time. Therefore, the device has virtually no time delay when opening the contact.

Таким образом, введение элемента ИЛИ-НЕ и выполнение элемента задержки в виде RС-цепи и диода позволяет повысить надежность функционирования устройства.Thus, the introduction of the OR-NOT element and the implementation of the delay element in the form of an RC circuit and a diode can improve the reliability of the device.

Claims

The invention relates to automation and telemechanics and can be used in switching controls. A device is known that eliminates the influence of chatter from an electromechanical switch, containing logic elements, resistors and iQ capacitors. The disadvantage of this device is the low reliability of the encoded information. The closest technical solution is a device containing a mechanical contact, connected through an inverter and a delay element to trigger 2. The disadvantage of this device is the low reliability of operation. The purpose of the invention is to increase the reliability of the operation. The objective is achieved by the fact that the second terminal through a resistor is connected to the power supply bus, the trigger and the delay element, an OR-NOT element is entered, and the delay element is made on the T C-Circuit and the diode, the common output RC-uepi is connected to the first trigger input and through the diode to the output of the OR-NOT element, the first input of which is connected to the second, the contact of the mechanical contact and the second trigger input, and the second This input is with a direct trigger output, while other RC circuits are connected to the power supply bus and the common bus, respectively. The drawing shows the circuit diagram of the device that contains the mechanical contact l, element 2 OR-NOT, trigger 3 , a delay element 4 consisting of a T C-circuit (resistor 5, a capacitor 6) in diow. 7, a resistor 8. 39 The device operates as follows. In the initial state, the contact 1 is open, and at the output of the element 2 ORINE a low voltage level determined by a high input potential from the power source through the resistor 8. The high potential at the input of the element OR NOT 2 also determines the initial state of the trigger 3, the direct output of which is set to a low voltage level. Therefore, the capacitor 6 R of the C-circuit of the delay element 4 is discharged through, the diode 7 and the open output of the element OR NOT 2. When the contact 1 is closed, a bounce occurs, but the output of the device (output of the trigger 3) does not occur. that the capacitor 6 does not have time to charge up to the switching level of trigger 3 (the constant charging time of the capacitor is chosen greater than the time required). After the cessation of bounce. (the contact is fixedly closed) the capacitor 6 is charged through the resistor 5 from the power supply and switches the trigger 3. At the direct output of the trigger 3 a high voltage level is formed which through the element OR-NOT 2 quickly discharges the capacitor 6 and again at the input of the trigger 3 a low voltage level is formed. When contact 1 is opened, the device returns to its original state with the arrival of the first positive bounce voltage, which is formed at the input of the trigger 3 from the power supply through the resistor 8. Subsequent bursts of the voltage bounce on the operation of the device do not affect The charge time of the capacitor 6 is longer than the bounce time. Consequently, the device has practically no time delay when the contact is opened. Thus, the introduction of an OR-NOT element and the execution of a delay element in the form of a T-circuit and a diode can improve the reliability of the device. The invention claims A device for eliminating the influence of contact bounce, comprising a mechanical contact, the first terminal of which is connected to the common bus and the second through a resistor with a power supply bus, a trigger and a delay element, characterized in that, in order to increase reliability, an AND LINE element is introduced into it, and a delay element is made on an RC circuit and a diode, with a common display of the RC circuit dinene with the first input of the trigger (a ger and through the diode with the output of the element OR NOT, the first input of which is connected to the second output of the mechanical contact and the second input of the trigger, and the second input to the forward output of the trigger, while the other terminals R of the C circuit connected to the power supply bus and the common bus, respectively. Sources of information taken into account during the examination 1. Gutnikov V. Integral electronics in measuring instruments. L., Energie, 1974, p. 140.

2. The patent of Germany M 24O9345, cl. N OZ K 17/16, 1976.