SU978010A1 - Rubber elasticity determination device - Google Patents

Description

The device relates to test equipment, namely, devices for determining the elasticity of rubber.

A device is known for determining the elasticity of rubber by rebound, made in the form of a pendulum, at the end of which a load with a striker is fixed, and a rebound height lock made of a spring grip and arrows 11].

The disadvantage of this device: is the presence of friction in the axes of the suspension of the pendulum and arrows.

The closest to the proposed technical essence and the achieved effect is a device for determining the elasticity of rubbers, comprising a housing, a drummer with .. placed in it, an indenter and an indicator of the height of the rebound of the hammer, made in the form of a scale and an arrow rotating around the t2J axis. 20

The disadvantage of this device is its relatively low accuracy (due to the presence of friction in the axis of the arrow, which affects the height of the rebound.,

The purpose of the invention is improving accuracy.

This goal is achieved by the fact that in the device for determining the elasticity of rubbers containing the housing, the drummer located in it with the indenter and the indicator of the rebound of the drummer, the indicator is made electronic, and the device is equipped with a ruler with marks fixed on the drummer parallel to the direction of its movement by the electronic zeroing unit, serially connected by a non-contact sensor of position of labels, a logic element and counters, the output of which is connected to the indicator input, serially connected by an impulse selector duration pulses, by a second logic element, a trigger whose output is connected to the second input of the first logic element, and a second trigger, whose input is connected to the counter output, and the output - to the second input of the second logic element, the second sensor output is connected

070010 with the input of the selector, and the input of zeroing the counter and the second inputs of the triggers with the block zeroing.

The drawing shows a block diagram of the proposed device.

The device comprises a housing, a drummer 2 with an indenter 3 located inside the housing. On the drummer, a ruler 4 with marks is fixed parallel to the direction of its movement. The proximity sensor 5 of the position of the labels with one of its outputs is connected in series with the first logic element 6 (circuit I) by a counter 7 and indicator 8. Another input of the sensor 5 is connected via a pulse duration selector 15 Q _f and the second logic element 10 (circuit I) with The P-input of the first RS is trigger 11, the output of which is connected to the second input of the first logic element 6. The second RS-trigger-20 rep 12 is connected with its output to the second input of the second logic element. 10. The S-input of trigger 12 is connected to the second output (trigger installation output) of the counter _ζ 7. The output of the reset unit 13, which sets the initial position of the circuit, is connected to S — the input of the first trigger 11, R — the input of the second trigger 12 and the input reset counter 7.

The device operates as follows.

Drummer 2 is raised to its initial height. Triggers 11 and 12 and counter 7 in the zero (initial) position, i.e.: ₃₅ at the input of logic element 6 connected to the direct output of trigger 11, logical 1, and at the input of logic element 10 connected to -direct output of trigger 12, logical O. ₄₀

When the drummer 2 moves at the moment of passing the mark on the line 4, an electric pulse appears at the output of the latter past the sensor 5. The number of pulses is proportional to the movement of the striker. These pulses through the logic element 6 are fed to the input of the counter 7, where they are summed. When the number of pulses reaches the set value (corresponds to the height of the impactor), an electric pulse appears at the second output (output of the u- ⁵ ® brand), which sets the output of trigger 12 to logical 1, while zeroing.

Thus, after the impact of the striker 2 on the test material 14, the number of pulses at the output of the counter is zero, and ι at the second input of logic element 10 is logical 1 *.

The selector 9 passes the pulses to the input of the logic element 6 with only 5 long duration, corresponding to the low speed (in the limit of zero) of the movement of the striker. Therefore, at the beginning of the reverse movement of the striker, the pulses do not pass to the input of the logic element 10, but arrive only at the input of the logic element 6. Thus, the counter 7 begins to count the pulses corresponding to the movement of the striker in the opposite direction.

As the projectile 2 moves in the opposite direction, its speed decreases, and the pulse duration at the output of the sensor increases.

When the pulse duration exceeds the value set by the selector 9, this pulse will arrive through the logic element 10 to the R-input of the trigger 11 and the logical O will appear at the second input of the logic element 6, i.e. the pulse count by counter 7 will stop and at the output of indicator 8 a number proportional to the height of the rebound of the indenter will be fixed.

To set the device to its initial state, an electrical impulse is issued from the output of the nulling unit 13, which sets the triggers and the counter to the initial states.

Thus, the proposed device can improve the accuracy of measurements by eliminating the influence of friction when registering the height of the rebound of the indenter.

Claims (2)

1.Reznvkovsky M.M., Lukomska A.N. Mechanical testing of rubber and rubber. M., Science, 1968, p. 259-261. 2. USSR author's certificate number 373584, cl. q 01 N 3/52, 1971 (prototype).