| 摘要 |
<p>A control system (10) for a spring applied, pressure released brake (16) is provided to control the pressure level in the brake (16) in response to operation of a control valve (22) to stage the pressure levels relative to the operating mode of the control valve. The control system (10) also provides two different fluid pathways (58, 60) that are individually operational to lubricate a winch and draw-works mechanism (18) in response to the operating position of the control valve (22). This system improves the response time needed to gradually release the brake (16).</p> |
