1、PDF外文：http:/ 三 英文文献 MEASUREMENT SCIENCE REVIEW, Volume 1, Number 1, 2001 MEASUREMENTS OF SELECTED PARAMETERS OF A HYDRAULICPUMP BY MEANS OF A COMPUTER-BASED MEASURING SYSTEM Tadeusz Zloto 1), Zygmunt Biernacki 2), Marek Kurkowski 2), 1) Institute of Machine Technology and Production Aut
2、omation,CzestochowaTechnical University,Al. Armii Krajowej 21, 42-200Czestochowa, Poland, e-mail:zlotoitm.pcz.czest.pl 2) Institute of Electronics and Control Systems, CzestochowaTechnicalUniversity,Al. Armii Krajowej 17, 42-200 Czestochowa, Poland,e-mail: biernacel.pcz.czest.pl , marekekbpoczta.one
3、t.pl Abstract: The basic characteristic parametersof the pump operation are presented. Theparameters are monitored by a computer-basedmeasuring system at a hydraulic stand. Thestructure of the measuring system and the constructionof the measuring converters applied inthe system are described.
4、 1 INTRODUCTION Due to their important advantages, hydraulicdrives and controls are commonly applied ina number of fields of mechanical engineering.The still increasing demand for hydraulic drivesencourages research on new constructional solutionsintended to improve operatingparameters,efficien
5、cy and to lower production cost. Each hydrostatic system has adisplacementpump as a basic part. The pump changes mechanicalenergy into the energy of pressure ofa liquid operating agent. Then, the latter kind ofenergy is transmitted to ahydraulic engine whereit is changed back into mechanical energy.
6、 At present, it is axial multipiston pumpswhich are the most often applied in high-pressuresystems. The compact construction of multipistonpumps makes it possible to obtain higherefficiency per unit of volume. Because of that theweight of machines in which multipiston pumpsare used may be lighter. I
7、n many respects, suchas reliability, efficiency, energy saving andautomation of industrial processes, the requirementson pumps areincreasing. Intensive researchon the construction of pumps will certainlybring about new developments. 2 CHARACTERISTIC QUANTITIES OFTHE PUMP OPERATION In a perfect
8、 pump, where no losses occur, thepower given out by the driving engine is equal tothe power supplied to the system by the operatingagent, according to the formula: t t tN M Q p (1) where: Nt is the theoretical power； Mt is the theoretical torque at the pump shaft； is the angular velocit
9、y of the shaft； p = p2 . p1 is the difference between forcingpressure p2 and suction pressure p1。 It is known 4 that volumetric losses, whichdeteriorate the theoretical efficiency of pumps,result mostly from leakages of the operatingagent from displacement chambers through gapsbetween displacement elements and the walls ofchambers or body of the pump. Knowing volumetriclosses one may
