Energy-conserving injection molding machine
    2.
    发明授权
    Energy-conserving injection molding machine 失效
    节能注塑机

    公开(公告)号:US5052909A

    公开(公告)日:1991-10-01

    申请号:US616752

    申请日:1990-11-16

    IPC分类号: B29C45/82

    摘要: A hydraulic injection molding machine incorporates a pump driven by a variable speed motor preferably of the brushless DC type. The machine controller outputs driving signals to adjust the speed of the motor so that the flow delivered by the pump substantially matches the hydraulic demand imposed during each phase of the machine operating cycle. The pump is preferably a variable displacement type and is connected to a fast responding pump control for selectively carrying out pressure compensation or flow compensation. The values of the motor driving signals are calculated so that the motor/pump combination is operated at or near maximum efficiency except when the pump control varies the displacement of the pump to effect pressure or flow compensation. Hydraulic transient response is further improved by connecting the output of the pump to an accumulator by way of a check valve.