1. orifice restrictor
(1) The internal throttle to external throttle, and the installation of the upper and lower chamber pressure gauge real-time display. Make maintenance easy, in particular, can easily be cleaned regularly, this is an internal restrictor incomparable.
(2) the throttling ratio. Throttle than the theoretical value of β is between 1.2 to 1.5, and 1.25 based on years of experience is preferred. Such maintenance, the need for precision spindle geometry before and after bearing geometric accuracy, concentricity, roundness and taper strictly controlled to ensure β values. Determine the value of e (eccentric amount spindle and bearing geometric center) according to the carrying capacity of the machine, so that the optimum β value.
(3) The oil chamber when the spindle is not installed, the oil port of oil each column must be consistent (observation), if not, should be taken to change the restrictor aperture method, changes its flow. In the cavity 4 as an example, is generally lower, left, and right chambers of the oil column between 20 ~ 25mm, the hole diameter is 0.25 ~ 0.4mm.
2. The film feedback restrictor
Film feedback restrictor bearing stiffness is great, but the machine in operation often appear to hold tile, brushed, lost pressure and so on. The most critical feedback film is a film, in practice believes locking bush, brushed the main reasons are: ① film due to plastic deformation; ② slow feedback. When the external load mutation, the film did not react, the shaft and the tile has been friction; ③ film fatigue. Film using a long time, fatigue deformation, the equivalent of changing feedback parameters.
Increasing the thickness of the film and use some of the material fatigue, you can receive good results. Generally rigid membrane, pre-load, reserve gap method. Specific approach is: 1.4mm thick film to 4mm thick rigid film, the inferior vena pad 0.05mm thick aluminum foil, so that the spindle is adjusted to the ideal position higher than the position of 0.05mm. The purpose is to force when the spindle (wheel weight, cutting force), the just return to the ideal center.
3. Improved fuel supply system
Hydrostatic bearing oil supply system, in addition to the coarse filter, fine filter, the rest of the components of the hydrostatic bearing has a protective effect. In the original system, based on improvements to the fuel supply system.
(1) connected pressure switch and pressure gauge in the throttle plate after the oil outlet (originally in front of the accumulator), so allows the operator to see the chamber pressure and the size of the inlet pressure. When the pressure is greater than a certain value, in order to immediately shut down, in order to avoid bearing locking. Such as: inlet pressure 2MPa, export chamber pressure 1.2 ~ 1.6MPa, 1.2MPa lower than would stop.
(2) increasing the digital detection device
Between the spindle and bearing hydrostatic bearing clearance 0.04 ~ 0.05mm, during which the oil has a certain resistance value, detect changes in the resistance, we can know the size of the gap. To the spindle pole, bearing another pole, measure its resistance changes. Send this post to a photoelectric alarm signal processing and control system amplifier, controlling the spindle motor start and stop, in order to avoid friction shaft and tile.
