【正文】
現(xiàn)代工程機械幾乎都采用了液壓系統(tǒng),并且與電子系統(tǒng)、計算機控制技術結合,成為現(xiàn)代工程機械的重要組成部分。系統(tǒng)性能的好壞,除滿足使用功能要求外,應從液壓系統(tǒng)的效率、功率利用、調速范圍和微調特性、振動和噪聲以及系統(tǒng)的安裝和調試是否方便可靠等方面進行。并聯(lián)系統(tǒng)中,當一臺液壓泵向一組執(zhí)行元件供油時,進入各執(zhí)行元件的流量只是液壓泵輸出流量的一部分。在串聯(lián)系統(tǒng)中,當主泵向多路閥控制的各執(zhí)行元件供油時,只要液壓泵的出口壓力足夠,便可以實現(xiàn)各執(zhí)行元件的運動的復合。4)按向執(zhí)行元件供油方式的不同,可分為串聯(lián)系統(tǒng)和并聯(lián)系統(tǒng)。3)按所用液壓泵形式的不同,可分為定量泵系統(tǒng)和變量泵系統(tǒng)。由于單桿雙作用油缸大小腔流量不等,在工作過程中會使功率利用下降,所以閉式系統(tǒng)中的執(zhí)行元件一般為液壓馬達。但閉式系統(tǒng)較開式系統(tǒng)復雜,因無油箱,油液的散熱和過濾條件較差。其結構緊湊,與空氣接觸機會少,空氣不易滲入系統(tǒng),故傳動較平穩(wěn)。開式系統(tǒng)油箱大,油泵自吸性能好。開式系統(tǒng)是指液壓泵從油箱吸油,油經(jīng)各種控制閥后,驅動液壓執(zhí)行元件,回油再經(jīng)過換向閥回油箱。The hydraulic presses system of the form and the evaluationThe hydraulic presses the ponent to carried out to standardize gradually, the series turn, its specification, species, quantity, functionses all had to raise very greatly, particularly is to adopt the new craft of new technique of electronics technique, servo technique...etc. after, the hydraulic presses the exaltation that the quantity of the system gets to show the highest , it developped the important function in national economy and the military industries.Set out from the different angle, can press the system to the liquid to be divided into the different form.1)Press the circulating way of the oil liquid, the liquid press the system and can is divided into the open type system and shut type open type system mean that the liquid pre