SU840787A1 - Device for measuring bounce time of electric contacts - Google Patents

Description

The invention relates to an electrical measuring technique and can be used for checking and sorting out electrical contacts. A device for measuring the time parameters of a relay is known, which comprises a pulse generator, an electronic key, a trigger, a main and additional pulse counters, an AND element, an NOT element, and a jumper l. The disadvantage of such a device is the length of the process of measuring contact bounce time when measuring various types of contacts (differing bounce times). The closest to the proposed technical entity is a device for measuring the time of electrical contacts, including a pulse generator, AND elements, impulse former, trigger, counter, counter polling unit, register, register polling unit, delay element, and digital printing unit 2. Disadvantage The known device is also sufficiently long. measurement process. The purpose of the invention is to reduce the measurement time. This goal is achieved in a tdp device for measuring the bounce time of electrical contacts, containing a series-connected pulse driver, a trigger, the first element AND, a counter, a meter polling unit, a register, a register polling unit and a digitizer, and a series-connected pulse generator, element the delay and the second element And, the output of which is connected to the second input of the polling counter of the counter, while the second input of the polling register register is connected to the second inputs of the digital printing unit trigger, the output of which is connected to the second input of the second element I, the third input connected to the input of the pulse generator, and BTOpc t the input of the first element I connected to the output of the pulse generator, additionally introduced in series the pulse generator, delay element, counter, register and block comparison, the output of which is connected to the second input of the main counter, the third input of the additional counter is connected to the output of the first element And, while the outputs of the additional counter are connected to the second with the inputs of the comparison unit, and the inputs of the additional pulse impulse generator are connected to the first and third inputs of the second element I.

The drawing shows a block diagram of the device.

A device for measuring the bounce time of electrical contacts contains a driver and pulse 1, trigger 2, first element 3, counter 4, counter interrogation unit 5, register b, register interrogator 7, digital printing block 8, pulse generator 9 11, an additional pulse shaper 12, a delay element 13, a counter 14 and a register 15, as well as a comparison unit 16.

The device works as follows.

In the initial state, the tested contact connected to the input of the device is open. The trigger 2 and the counter 4 are in the zero position, a code is written into the clock 14, one less than its maximum code.

When the tested contact closes at the moment of the first contact, the contact signal from the output of the imaging device 1 triggers the trigger 2 into one state, while the finger is allowed to pass pulses from the generator 9 impulses to the inputs of counters 4 and 14, which change their state with each incoming pulse . i

The pulse shaper 12 at the time of the occurrence of the contact in the contact being checked produces a signal by which the counter code 14 is written to the register 15 for storage, and the same signal delayed on the delay element 13 resets the counter 14 to zero. In the future, the counter 14 will be filled with each & l pulse from the generator 9 pulses.

The inputs of the element 11 receive the enable signal from trigger 2, impulses delayed by the delay element 10 from the generator 9 pulses and single signals at the time the contact disappears in the tested contact, the frequency of the pulses at the generator output being selected from the conditions for obtaining the required accuracy of chatter time measurement contacts. At the moment when the contact disappears by signals from the output of the element 11, permission is given to the block 5 of interrogating the counter for reading the code of the instantaneous state of counter 4 and storing it in register 6.

The presence of the delay element 10 is caused by the need to separate in time the moments of the signal input to the counter 4 and read the states of the counter for storage.

During bounce, the counter 4 is continuously filled, and the counter 14 is filled only in the stand between the touches of the contact being checked.

Since the time of each subsequent departure of the checked contact is shorter than the time of the preceding departure, the counter code 14, which is shorter than before, is recorded in register 15 during chatter with each touch of the checked contact. The presence of the delay element 13 is caused by the need to separate in time the moments of recording in register 15 of the counter code 14 and the moments of resetting this counter to the zero state.

At the end of the debounce of the tested contact, the register 15 stores the counter code 14 corresponding to the time of the last departure of the contact (the shortest departure time).

After the last touch of the contact being checked (bounce end, the counter code 14 reaches the value of the code recorded in register 15, and the comparison block 16 outputs a signal to the register 7 polling block to read the stored code (bounce time) on the digital block, 8 to print this code, as well as to counters 4 and 14 and trigger 2 to reset them.

Thus, the result of the contact bounce time becomes known after the end of the bounce, after a time equal to the time of the last departure of the contact being checked, which is very small compared to the bounce time, as a result of which the cycle time of contact bounce is reduced and the productivity of the measurements increases.

Claims (2)

1. Authors certificate of the USSR 551601, CL G 04 F 10/04, 1974. 2. Authors certificate of the USSR 566232, cl. G 04 F 10/06, 1974.