SU941704A1 - Device for diagnosis of hydraulic drive - Google Patents

Description

(54) DEVICE FOR DIAGNOSTIC HYDRAULIC DRIVE

one

The invention relates to hydraulics and can be used for the automated diagnosis of onboard aircraft hydraulic actuators with variable fluid flow and variable load.

A device for diagnostics of a hydraulic actuator is known, comprising electrically interconnected sensors of measured parameters of a power source and actuators of the hydraulic actuator, a source of diagnostics signals, a comparison node and an indicator 1.

The disadvantages of the known device are low accuracy and limited functionality.

The purpose of the invention is to improve the accuracy and expansion of functionality.

This goal is achieved by the fact that the device for diagnostics of the hydraulic drive is equipped with a normalization unit for generating a normalized pressure signal and a normalized value of the pressure measurement interval, a mode recognition unit for generating signals corresponding to the steady and unsteady hydraulic operation modes, and a node for determining the type of hydraulic drive condition, and the source of diagnostics signals is designed as a master of reference levels of measured parameters, the latter being associated with you One of the inputs of each of the normalization nodes of comparison and recognition, the sensors of measured parameters are connected to the inputs of each of the comparison nodes, the Q rate of linearization and recognition, the comparison node is connected to other inputs of the normalization and recognition nodes, and the output of one of the inputs of the recognition node and with the first input of the node for determining the type of state, the normalization node is connected

15 by another input with the output of the recognition node, and one of the outputs with the second input of the node for determining the type of hydraulic drive, the recognition node is connected to the third input of the node for determining the type

2Q of the state of the hydraulic drive, and the output of the latter with an indicator.

FIG. 1 shows a diagram of a device for diagnosing hydraulic drive; in fig. 2 is a diagram of formation of a normalized pressure signal and a normalized value of a pressure measurement interval in a node for normalization; in fig. 3 is a diagram of the formation of signals corresponding to the steady-state and unsteady modes of operation of the hydraulic drive in the mode recognition node.

The device contains a pressure sensor 1, a liquid level sensor 2, a power source speed sensor 3 (not shown) a power source switch-on signal (pump) sensor 4, an actuator turn-on signal sensor 5 (not shown), a setpoint 6 reference levels parameters to be measured; a comparison node 7, a normalization node 8, a mode recognition node 9, a hydraulic drive condition definition node 10, and an indicator 11.

The formation scheme in node 8 of normalization (Fig. 2) of the normalized pressure signal P and the values of the pressure measurement interval T includes adders 12, 13 and 14, multipliers 15, 16 and 17, differentiation unit 18, reversible counter 19, dividing device 20 and converter 21; The formation scheme in node 9 of the recognition of the signal mode (Fig. 3) corresponding to the steady-state and unsteady operating modes of the hydraulic drive (events A and B, respectively) includes element 22 and 23 and 24 to NOT 25. At the same time, the dial 6 and sensors 1-5 b the outputs with the inputs of each of the nodes 7 compare normalization 8 and recognition 9, the node 7 comparison is connected with other inputs with the outputs of the nodes normalization 8 and recognition 9, and the output with one of the inputs of the recognition node 9 and with the first input of the node 10 determining the type of state nor, node 8 normals ation another input coupled to the output node 9 discrimination, and one of the outputs - to a second input node 10 determining the form of the condition recognition unit 9 is coupled with the third input of the output unit 10 determining states of the form, and the last output - with the indicator I.

The device for diagnostics of the hydraulic drive works as follows.

The operation mode recognition node 9 senses signals from sensors 1-5 and solves a series of logical equations. At the beginning of the work cycle, event A is generated, as follows:

A () AiHAlr.p. , (

where L, is the reference signal (level) of the preset 6;

P - pump speed signal; - pump start signal; T is the negation of the switching signal of the executive bodies; L is a sign of a disjunction. A signal corresponding to event A is a sign of the steady state of the hydraulic drive. Transition mode corresponds to event B:

In (n Lj) L IH L if.r.

In this case, the comparison of the pump speed parameter r with the level Lj is performed in the node

7, in which, in the presence of event A, the pressure signal P is compared with reference levels L2; Lj; LJ and Ub liquid level with reference level C.

In node 10 of the state view definition, events are generated; corresponding: L (Р LJ) -pressure in the hydraulic drive is below the norm;

C2 AA (P L) L () —the pressure in the hydraulic actuator has reached the limit value;

Cj A А (Р L.,) Л () А V6 L hydraulic actuator is unpressurized;

C A A (P lg) A () the pressure in the hydraulic actuator is above the norm.

Node 8 normalization performs calculations by the formula:

, Pi / Tnt / n-Le / Lio, (2

where m is the number of discrete pressure measurements P made in the time interval when

APjH - RH O. (3)

Condition 3 is implemented by mode recognition node 9. At L O, the measurement cycle starts again and at the same time at the node

In normalization, expression (2) is implemented. The signal corresponding to P enters the comparison node 7, where it is compared with the reference Lg level. In this case, if Su P LS - hydraulic losses in the hydraulic drive exceed the allowable ones. When P Lg, the expression is calculated:

T-mtt / n-Le / L, (4

where and is the cycle of pressure change P. The value of is compared in node 7 by comparison with the levels of LgH Ljo. At node 10, the formation of logical equations is carried out: - the pump capacity does not correspond to the specified flow rate () L; A (T L jo) - hydraulic drive is operational; The Cg () A state of the executive orLs (, 5) of the gans does not meet the specified requirements.

The information from the node 10 for determining the type of state is supplied to the indicator 11.

The application of the proposed device in the systems of automated diagnostics of onboard aircraft hydraulic actuators will increase their accuracy and expand functionality.

Claims (1)

Invention Formula A device for diagnostics of a hydraulic drive, comprising electrically interconnected sensors of measured parameters of a power source and actuators of the hydraulic drive, a source of diagnostic signals, a comparison unit and an indicator, characterized in that, in order to increase accuracy and enhance functionality, it is equipped with a normalization unit for generating a normalized pressure signal and a normalized value of the pressure measurement interval, by the mode recognition node for generating signals, respectively These are steady-state and unsteady modes of hydraulic drive, and a node for determining the type of hydraulic drive state, and the source of diagnostics signals is designed as a generator of reference levels of measured parameters, the latter being connected to one input of each of the comparison and recognition normalization nodes, sensors of measured parameters are connected to the inputs of each of the comparison, normalization and recognition nodes, the comparison node is connected to the outputs of the normalization and recognition nodes by other inputs, and you the stroke — with one of the inputs of the recognition node and with the first input of the state view definition node, the normalization node is connected with another input with the recognition node output, and one of the outputs with the second input of the hydraulic drive condition definition node, the recognition node is connected with the third the input of the node for determining the type of hydraulic drive condition, and the output of the latter with an indicator. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 511440, cl. F 15 B 19/00, 1974. YU