A system has an electric motor having a stator and a rotor. The rotor rotates with a shaft and the shaft drives a fluid rotor. A control senses a fault condition on the electric motor. The control actuates a speed reduction feature when a fault is detected to bring rotation of the motor rotor and the fluid rotor to a stop more rapidly than if the speed reduction feature had not been actuated.

The present invention provides a splinter shield for a vacuum pump, capable of reducing costs of the splinter shield by obtaining a single sheet of splinter shield having a required strength, in which fastening strength to a fixing groove is enhanced to prevent the splinter shield from bending toward the inside of a pump and coming into contact with equipment inside the pump when air rushes into the pump through an inlet port and to prevent the splinter shield from falling. Furthermore, attachment and removal of the splinter shield with respect to the inlet port are facilitated. The present invention is a splinter shield for a vacuum pump in which a rim formed in a circumferential edge portion of the splinter shield is inserted into a fixing groove that is provided in a concave manner in an inner circumferential portion of an inlet port, and the splinter shield is provided in a tensioned manner to the inlet port by pushing a retaining ring into the fixing groove, wherein locking parts that are locked into the retaining ring at a plurality of sections in the rim are provided in a standing manner at substantially right angles to the rim.

A compressor arrangement having a main compressor, a piping system containing process gas to be extracted after the shut-down of the main compressor and one or more components emitting or leaking depressurized process gas while the compressor is operating or starting up; the compressor arrangement further comprises one or more collectors arranged to collect the depressurized process gas emitted from said components and an additional compressor fluidly coupled with the piping system and with the collectors in in order to compress the depressurized process gas coming from the components while the compressor is starting up or operating and to compress process gas coming from the piping system after a shut-down of the compressor.

A system includes a dynamic compressor and a controller. The dynamic compressor includes a motor having a driveshaft rotatably supported within the dynamic compressor and a compression mechanism connected to the driveshaft and operable to compress a working fluid upon rotation of the driveshaft. The controller is connected to the motor and includes a processor and a memory. The memory stores instructions that program the processor to operate the motor to compress the working fluid at a motor speed greater than a predicted minimum surge speed plus a control margin, determine when surge events have occurred, store, in the memory, an indication of each surge event that the processor determined to have occurred, and determine whether or not to take a protective action when the processor determines that a surge event has occurred.

A vacuum pump and a temperature control device are capable of preventing, with a simple configuration, overheating and overcooling of a pump that are caused due to abnormality in a temperature sensor used to control a heater or a water-cooling solenoid valve that is provided to prevent the deposition of products. Problems such as overheating and overcooling of a heater can be avoided in a case where a temperature sensor system fails and consequently the measured temperature continues to be constant between the upper limit and the lower limit. TMS function controls the measured temperature of the temperature sensor to a target temperature. Thus, if an application such as a target to be heated or a heater capacity is identified, the same cycles of turning ON/OFF of the heater or the water-cooling solenoid valve are repeated, and the upper limit of the time in which the ON/OFF state is sustained continuously is determined. An allowed time considering a margin is provided for this upper limit, and the ON/OFF state is changed so that the ON state or the OFF state is not continuously sustained beyond the allowed time.

In an aircraft gas turbine engine equipped with a bleed-off valve that bleeds intake air compressed by a compressor exterior and an electric actuator that drives the valve when current is supplied, a required valve opening θr and a current value Ia corresponding thereto are calculated and Ia is supplied to the actuator to bring valve opening θ to the required opening θr. Then Ia is compared with a current value Ib and if Ia exceeds 1b, the valve is estimated to have failed and another current value Ic is calculated and Ic is supplied to enlarge valve opening toward wide-opening θw. Then a current value Id is calculated and supplied to decrease valve opening toward θr. Next, Id is compared with Ib and the valve is determined normal when Id is equal to or smaller than 1b. If not, it is determined to be faulty.

The present invention relates to a check valve unit (1, 100, 200, 300, 400) having a shaft bearing body (10, 110, 210, 310, 410) with an at least substantially cylindrical mounting portion (11) extending along an axial direction (A) and an axially extending valve shaft (20, 120) mounted therein. The latter is displaceable along the axial direction (A). The check valve unit (1, 100, 200, 300, 400) further includes a valve head (25, 125) with a sealing surface (33, 133), wherein the valve head (25, 125) is disposed on a distal end (21) of the valve shaft (20, 120) in the axial direction (A), the distal end (21) facing away from the mounting portion (11). Further, a damping reservoir (50) is provided inside the shaft bearing body (10, 110, 210, 310, 410). A volume of the damping reservoir (50) is changed by axial movement of the valve shaft (20, 120). In order to obtain a well-defined times for opening and closing under given conditions and to make the check valve unit (1, 100, 200, 300, 400) less prone to making noise, at least two channels (46a, 46b) are provided in parallel, each of them constituting a fluid connection between the damping reservoir (50) and an outside (70). The damping reservoir (50) is, apart from the channels (46a, 46b), at least substantially enclosed. Each channel (46a, 46b) has a length being at least ten times a hydraulic diameter of the respective channel (46a, 46b).

A method for leak detection in a system including a compressor. A first pressure differential is determined in the system via a first pressure differential indicator (PDI). The first pressure differential is converted into a first flow measurement. A second flow measurement is determined downstream of the compressor using a second PDI. The first flow measurement and the second flow measurement are compared to determine whether a leak exists between the first PDI and the second PDI.

A vacuum pumping arrangement comprises a first pump which has a first inlet and a first outlet. The first inlet is fluidly connected to a first common pumping line. The first common pumping line includes a plurality of first pumping line inlets each of which is fluidly connectable to a least one process chamber within a group of process chambers that form a semiconductor fabrication tool. The vacuum pumping arrangement also includes a reserve pump which has a reserve inlet and a reserve outlet. The reserve inlet is selectively fluidly connectable to each process chamber within the group of process chambers that form the semiconductor fabrication tool. The vacuum pumping arrangement additionally includes a controller which is configured to selectively fluidly isolate the pump from one or more given process chambers and selectively fluidly connect the reserve pump with the said one or more given process chambers.

A method of operating a heat exchanger system in which a compressor, which is drivable by a motor, is fluidly interposed between an evaporator and a condenser following receipt of a shutdown command is provided. The method includes positioning inlet guide vanes (IGVs) of the compressor in a first position in the event of at least one of a first precondition being in effect and the first and a second precondition both not being in effect. The method further includes positioning the IGVs in a second position in an event the first precondition is not in effect but the second precondition is in effect, ramping a speed of the compressor down until a third precondition takes effect, removing power from the motor and positioning the IGVs in the first position once power is removed from the motor.