초록 ▼

A portable electrohydraulic servo valve analyzer, which has microprocessor-based electronic controller and is operable in a fully automatic mode and a manual mode, is disclosed. The system also includes: a hydraulic manifold block and an adapter block for receiving different servo valve; a servo amp

A portable electrohydraulic servo valve analyzer, which has microprocessor-based electronic controller and is operable in a fully automatic mode and a manual mode, is disclosed. The system also includes: a hydraulic manifold block and an adapter block for receiving different servo valve; a servo amplifier and electrical hook-up to the servo valve; pressure gages and hydraulic shut-off valves; a keypad for entering operating input commands and values; two digital displays indicating the current supplied to the valve and the resulting hydraulic flow rate through the valve, and a special turbine flowmeter capable of highly accurate operation of at least three orders of magnitude of flow rates. Most of the system is housed in a single small portable aluminum suitcase. Hydraulic flow is measured by digitally timing the periods between detection of the successive rotating vanes of the turbine, and compensating for nonlinearities in turbine rotation rate at low flows. An optional x-y plotter which may be housed in another suitcase is used in the automatic mode to produce a hard copy of the test results showing the hydraulic flow rate through the servo valve as a function of DC current signal that varies with time and is supplied as an input signal to the valve. This input signal is preferably varied automatically in a manner that puts the valve through a test cycle including its full range of operation. Thus, the test results indicate whether the servo valve is operating properly or needs re-calibration or repair. Preferred methods for operating this servo valve analyzing system are also disclosed.

대표청구항 ▼

CM,14. A high-accuracy, easy-to-use, transportable system which is operable in a fully automatic mode for testing the operation of an electrohydraulic servo valve by generating a varying electric input command signal and monitoring and recording hydraulic performance of the servo valve in response t

CM,14. A high-accuracy, easy-to-use, transportable system which is operable in a fully automatic mode for testing the operation of an electrohydraulic servo valve by generating a varying electric input command signal and monitoring and recording hydraulic performance of the servo valve in response to the varying command signal, the system comprising: manifold means for making temporary hydraulic connections to the servo valve; electrical connector means for making electrical connection to at least one electrical input lead of the servo valve; turbine flowmeter means for accurately sensing fluid flow over the full dynamic range of the servo valve, including very low flows, the flowmeter means including a flowmeter body having a passage therethrough and a turbine having at least three blades disposed at least partiallly within the passage for rotation in response to fluid whose flow rate is to be measured impinging on the vanes, and vane detector means for generating an electromagnetic flow signal whose period corresponds inversely to the rate of rotation or the turbine as determined by the presence and absence of the vanes in a predetermined location within the body, and dedicated signal processing means for measuring the period of the electromagnetic flow signal by selectively counting pulses of a high-speed time base during such period; keypad means for accepting operator input commands which specify at least one test parameter; servo amplifier means for producing an amplified analog current signal to be input into the servo valve; analog-to-digital means for providing a digital feedback signal whose value corresponds to the magnitude and polarity of the amplified current signal being supplied to the servo valve; plotter interface means for transmitting data and control signals to x-y plot means so that current and flow measurements may be recorded on permanent visual presentation means; and centralized digital electronic controller means for automatically controlling the overall operation of the system in an automatic test mode which attempts to cycle the servo valve at least once through its full nominal range of hydraulic flows, the centralized means including at least one microprocessor and memory means for storing a control program and selected parametric data for configuring the system to produce current and flow measurements on an x-y plot having predetermined scales for input current and hydraulic flow rate.