SU1404831A1 - Force-measuring device - Google Patents

Description

(21) 4152430 / 24-10

(22) 11/26/86

(46) 06.23.88. Bul No. 23

(71) Kiev Institute of Automation. XXV Congress of the CPSU

(72) N.Ye. Zakharchenko, N.V.Bon, V.G. Gulevaty and N.P.Veklich (53) .531.781 (088.8)

(56) USSR Copyright Certificate No. 369500, cl. G 01 R 15/08, 1970.

USSR Author's Certificate No. 718721, cl. G 01 G 19/28, 1976.

(54) DEVICE FOR MEASURING EFFORTS

(57) The invention relates to instrumentation. The purpose of the invention is to simplify the device and ensure its reliability. The operation of the device is based on the principle of compensating for the measured forces of the compensator in the negative chamber 22. In the output line of the meter 1, a pressure is formed, which is the measure of the measured. the effort of the working subrange measured.

W

with

00

&R

neither The measurement subbands are switched by the switch 14 in the forward and reverse directions. The pulses of elements 36 and 37 form successively the signals in the output lines of the circuit

The invention relates to instrument engineering and can be used in primary measurement converters, for example, in weighing instruments.

The purpose of the invention is to simplify the device and improve its reliability.

The drawing shows the proposed device.

The device contains a meter 1, the input of which is connected to the line 2 of the measured force, the compensation input - through a normally closed contact 3 with the input of the compensated ipa 4 measured force, which consists of two parallel-connected repeaters 5 and 6 with positive 1M and negative shifts, the outputs of which are connected through normally open contacts 7 and 8, switch 9, capacitance 10 and repeater 11 with compensation input of meter 1. The supply pressure to repeater 11 is connected via a constant resistance 12. Output The meter 1 is connected to the inputs of the block 13 of indicators and the switch 14 of the measurement subbands, the outputs of which are connected to the control inputs of the block 13 of indicators. Two additional outputs of the switch 14 are connected to the control inputs of the switch 9 and through the element OR 15 with the control Kyczym input of a normally closed contact 3. Meter I contains a pneumatic adder 16 which is switched on with a constant resistance 17, power amplifier 18 and dividers 19 and 20 connected to the negative feedback chamber 21 according to the scheme of pneuomoilit, the measuring input of which is connected to the input of the meter 1, the negative chamber 22 is connected to the compensating input of the measurer 1. The block 13 of the indicators with keep under four (the number of subbands) indicator corresponds a 23-26 shka

check switch 14 and using the switch 9 set the compensation pressure in the negative chamber 22 of the adder 16, creating a compensation force. 1 il.

27 - 30 measurement subranges. The input of unit 13 is connected with an arrow 31 displaying, and the control inputs are connected with corresponding indicators 23-26. The switch 14 of the measurement subbands contains two comparison elements 32 and 33, one multi-polar inputs of which are connected to the outputs of the corresponding setters 34 and 35 pressures of the upper (0.1 MPa) and lower (0.02 MPa levels of triggering, others with the input of the Switch 14. The outputs of the comparison elements 32 and 33, with the corresponding pulsers 36 and 37 with variable resistances 38 and 39, are connected with the additional outputs 14 and one input of the elements And parallel connected switching chains, the number of which is equal to the number of measurement subranges. Each chain, except the first, contains two elements And 40 and 41, 42 and 43, 44 and 45 and one element 46 and 47 or 48 Each chain, except the last one, includes one BANCH 49 and 50 or 51 elements and one breaker 52–54 connected by an output through capacitors 55–57 with another input of the AND 40 or 42 of its chain and another input of the element Both 4.1 and 43 or 45 follow the chain. The output of the first elements AND 40, 42, and 44 is connected to the control inputs Erasing the corresponding elements 46 to 48 of the memory, and the outputs of the second elements AND 41, 43, and 45 are connected to the inputs. Memorizing the corresponding elements 46 to 48 of the memory, the outputs of which are connected to the inputs of the elements of the prohibition of 50 or 51 of their chains and the control inputs of the elements of the prohibition of 49 - 51 of the preceding chains. The entry element BAN 49 of the first chain is connected to the air supply line. The outputs of the elements of the prohibition.49 - 51, which are

The chains and switches 14 are connected to the inputs of the corresponding switches 52 - 54, the control inputs of which are connected to the outputs of the pulsers 36 and 37 via the OR 58 element, the output of the last chain and the switch 14 are connected to the output of the memory element 48 and another input the first element AND 44 of the last fourth chain.

The device works as follows.

The operation of the device is based on

ten

SPP, 2ЛРиЗ ДРв from the integral chamber 22 adder 1

Switching of subranges and rhenium is done in the forward and reverse directions; switching in the forward direction of the first to fourth subranges occurs when

MOUTH oh, 1 Sha

and the impulse of set duration arising in connection with this for element 36. Switching in the reverse direction (from the fourth to the last

compensation of the measured usi-15th sub-band) occurs when

LIA by the efforts of the compensator in the negative chamber 22 and the output of the meter 1 through dividers 19 and 20 in the chamber 21 of the negative feedback. In the output line of the meter 1, pressure P is generated, which is a measure of the measured force of the working subrange of measurement. R

EX

 0.02 MPa

20

where is f

F.

 K (F - F,),

in „0.1 MPa,

OUT

0.02 MPa P

measured force in line 2; compensation force in the negative chamber 22 of the adder 16;

and is realized by the pulse of the element 37 of the switch 14. The pulses of the elements 36 and 37 form successively the signals in the output lines of the peg switch circuit 14 and use the switch 9 to set the compensation pressure P in the negative chamber 22 of the adder 16, which creates a compensating force F. setting the compensation pressure P pulse

OFF

from the output of one of the elements 36 or 37, contact 3 disconnects the camera 22 from the input of the compensator 4 and connects the pneumatic gain factor of its output to the camera 22 with an amplifier switch settable 9, and in the switch 14 it turns off

The connection of the output lines of chained handles to the other inputs of all elements AND 40 - 45, while the output signal of one of the chains is locked in the other input of the first element AND 40 or 42 of its chain through the capacitor 56 or 57 and in the other input of the second element 41 and 43 or 45 subsequent chain through the tank 55, 56 or 57.

When the device is operating on the first measurement subband (, uF, P 0), discrete signal 1

variable resistance 20.

The range of measured force F is divided into n equal measuring subranges, each with a force uF

Рма.с П- 5 v (w-1) F,

where m is the number of the working subrange

measurements. In this way

35

K-f,

  - (m-l) UF

Oh and f -e L F.

The pneumatic amplifier is tuned to variable resistance 20 so that when

40

in the output line of the first chain, the indicator 23 of the scale 27 of the first measurement subband lights up. The arrow 31 reads off on a scale of 27. When switching to the second sub-band (t 2, D F 6 F 6 2 L F), the output pulse of element 36 generates a signal at the output of element And 41, which in turn sets the signal to be memorized at the output of element 46 memory The signal in the output line gg of the BANNER 49 element of the first chain disappears (indicator 23 is extinguished) and a signal appears in the output line of the BANNER 50 element of the second chain, the indicator 24 of the second scale 28 turns on

f Oh, f uF,

Boix bclx

 0.02 MPa; Oh, 1 MPa.

At the output of repeaters 5 and 6, positive (+ R) and negative (-UP) pressure shifts are established, creating an & F or -AF force in chamber 22. The scales 27-30 of the four measurement subranges are labeled as follows:

27- O - LR;

28 uF - 2 UF; 29-2 vF - 3 uF;

scale

30-3 UF - F

mslshs

The forces F, 2uF, 3uF are formed by the camping pressure corresponding to

SPP, 2ЛРиЗ ДРв negative chamber 22 of the adder 16.

The switching of the measurement subbands is performed by the switch 14 in the forward and reverse directions. Switching in the forward direction (from the first to the fourth subband) occurs when

MOUTH oh, 1 Sha

and arising in connection with this pulse of a specified duration at the output of the element 36. Switching in the opposite direction (from the fourth to the first

 0.02 MPa

and is realized by the pulse of the element 37 of the switch 14. The pulses of the elements 36 and 37 form successively the signals in the output lines of the peg switch circuit 14 and use the switch 9 to set the compensation pressure P in the negative chamber 22 of the adder 16, which creates a compensation force F. pressure compensation P pulse

in the output line of the first chain, the indicator 23 of the scale 27 of the first measurement subband lights up. The arrow 31 reads off on a scale of 27. When switching to the second sub-band (t 2, D F 6 F 6 2 L F), the output pulse of element 36 generates a signal at the output of element And 41, which in turn sets the signal to be memorized at the output of element 46 memory The signal in the output line of the BANCH 49 of the first chain disappears (indicator 23 is extinguished) and a signal appears in the output line of the BAN 50 of the second chain, the indicator 24 of the second scale

measurement range. At the same time, the pressure LR of the output of the repeater 6 is positively shifted through a closed pulse of the element 36, contact 7 is set in the negative chamber 22 of the adder 16. The compensation pressure P AP pressure Pg drops to the lower level, the pulse of the element 36 disappears, arrow 31 drops to the lower values of the scales 27-30 and shows the pressures that should be read on a scale 28 of the second subband. The transition to the third subrange (, AF) is accompanied by the formation of a pulse element 36 of the signal at the output of element And 43, which sets at the output of element 47 a command with a memory that eliminates the signal in the output line of the BAN 50 element of the second chain (the indicator 24 is quenched) and forms it the output lines of the third chain by the signal of the BAN 51 element. The indicator 25 on the scale 29 of the third subband lights up. At the same time, the pressure 2 nd: p output of repeater 4 through a closed pulse contact 7 is set in the negative chamber 22 of the adder 16. The compensation pressure P becomes equal to: 2 UP, the pressure drops to the lower level, the pulse of the element 36 disappears, arrow 31 drops to the lower values of the scales 27 - 30 and its readings should be calculated on a scale 29 of the third measurement subband. In the same way, switching to the fourth subrange (t 4, 3 D F Her F). The output signal of the -48 memory element and the last sub-band, set by the output command of the And 45 element, eliminates the output signal of the BAN 51 element of the third chain (the indicator 25 goes out) and lights the indicator 26 on the fourth subband. In this case, the compensator 4 installs. P, 3 L p. Similarly, the reverse switching of the measurement subrange scales occurs at Pgbix 0.02 Sha. For example, switching from the third subband to the second occurs as follows: the pulse of element 37 generates a signal at the output of element 42, which eliminates the output command of element 47.pam, as a result of which the signal in the output line of the BAN 51 of the third chain disappears (pe extinguish indicator 25) and voz0

five

0

five

0

five

0

five

0

five

It detects in the output line of the BAND 50 element of the second chain, the indicator 24 of the scale 28 of the second measurement subband lights up. Simultaneously, the pressure of the other output of the repeater 5 with a negative shift through a closed pulse contact 8 is installed in the negative chamber 22 of the adder 16 and forms there equal to others. The pressure rises to the upper level, the pulse at the output of the element 37 disappears, the arrow 31 rises to the upper values of the scales 27-30 and its reading should be counted on the scale 28 of the second measurement subband. ,

Claims (1)

Formula invention A device for measuring forces, which contains a pneumatic amplifier, the positive input of which is connected to the line of measured force, the compensation input to the force compensator by means of a switch, and the output is connected to the indicator unit arrow and the measuring subranges switch inputs switching and two elements of comparison, one of the different inputs of which are connected to the outputs of the pressure control units of the upper and lower levels of the operating system, others - with the input of the switch, the outputs of which It is connected to the control inputs of the indicator block, which is characterized by the fact that, in order to simplify the device and increase its reliability, the force compensator is designed as two parallel-connected repeaters with positive and negative shifts, the inputs and outputs of which are connected to the compensating input of the meter ; the inputs are through a normally closed contact, the outputs are through two normally open contacts of the switch, a capacitor and a repeater, while two pulsators are connected to the switch of the measurement subbands, connected by inputs to the outputs of the corresponding comparison elements, and outputs from the inputs of chains switching and two additional outputs of the switch connected to the control inputs of the switch and through the element OR to the control input of the normally closed contact.