US20060222506A1 - Rapidly pumping out an enclosure while limiting energy consumption - Google Patents

Rapidly pumping out an enclosure while limiting energy consumption Download PDF

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Publication number
US20060222506A1
US20060222506A1 US11/396,574 US39657406A US2006222506A1 US 20060222506 A1 US20060222506 A1 US 20060222506A1 US 39657406 A US39657406 A US 39657406A US 2006222506 A1 US2006222506 A1 US 2006222506A1
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stages
configuration
parallel
during
series
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Jean-Luc Rival
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Alcatel Lucent SAS
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Alcatel SA
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
    • F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C25/00—Adaptations of pumps for special use of pumps for elastic fluids
    • F04C25/02—Adaptations of pumps for special use of pumps for elastic fluids for producing high vacuum
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/02—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids specially adapted for several pumps connected in series or in parallel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/08—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by varying the rotational speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/10—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by changing the positions of the inlet or outlet openings with respect to the working chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C18/126—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with radially from the rotor body extending elements, not necessarily co-operating with corresponding recesses in the other rotor, e.g. lobes, Roots type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2220/00—Application
    • F04C2220/30—Use in a chemical vapor deposition [CVD] process or in a similar process
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2270/00—Control; Monitoring or safety arrangements
    • F04C2270/05—Speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2270/00—Control; Monitoring or safety arrangements
    • F04C2270/07—Electric current
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2270/00—Control; Monitoring or safety arrangements
    • F04C2270/58—Valve parameters

Definitions

  • the present invention relates to vacuum pumping devices capable of establishing and maintaining a suitable vacuum in an enclosure.
  • the substrates are placed in a loading chamber (known as a “load lock”) that is connected to a vacuum pumping device for lowering the pressure inside the loading chamber to a value that is satisfactory for subsequently transferring the semiconductor substrates into a process chamber in which there is a vacuum suitable for fabrication purposes.
  • a loading chamber known as a “load lock”
  • a vacuum pumping device for lowering the pressure inside the loading chamber to a value that is satisfactory for subsequently transferring the semiconductor substrates into a process chamber in which there is a vacuum suitable for fabrication purposes.
  • each substrate loading or unloading operation requires the gas pressure in the loading chamber to be lowered and then raised, thus requiring frequent intervention by the vacuum pumping device.
  • the loading chamber must necessarily have a volume that is suitable for containing one or more flat screens.
  • the loading chambers used for fabricating flat screens are of large volume, generally about 500 liters (L) to 1000 L and sometimes exceeding 5000 L, and these chambers need to be pumped out as quickly as possible.
  • the problem posed by the invention is to pump out a large-volume enclosure quickly so as to reach a suitable vacuum quickly inside the enclosure, while reducing the dimensions of the vacuum pumping device, and while limiting the energy it consumes to reach a satisfactory vacuum.
  • the invention results from the observation that a given vacuum pumping device generally presents a characteristic of speed as a function of pressure that presents a maximum in some given pressure range, with the particular pressure range for maximum speed depending on the architecture of the vacuum pumping device.
  • the invention takes advantage of that observation to devise a vacuum pumping device of variable geometry in which the geometry of the device is caused to change on one or more occasions in order to optimize the speed of the pumping device during each stage of pumping, i.e. during the various successive ranges of pressures within the enclosure that is being pumped out.
  • the invention thus achieves the looked-for result by using a multi-stage dry mechanical pump with a scheme for intelligently connecting the various stages in series and parallel modes, possibly also in combination with controlling the velocity of the pump.
  • a plurality of configurations for the pumping stages are thus used in succession, which configurations succeed one another as the intake pressure is reduced, and at all times the configuration that is selected is the configuration that provides the maximum pumping speed for the pumping device.
  • a changeover is made from one configuration to the next, either on the basis of timing adapted to the volume that is to be pumped out, or on the basis of the instantaneous electricity consumption of the pump motor, or on the basis of pressure information obtained from a pressure gauge measuring the pressure inside the enclosure that is being pumped out.
  • a pump of relatively small size is capable of pumping at higher speed, thus avoiding the need to use larger pumps driven by larger motors and consuming more energy.
  • the savings in terms of pumping device volume and energy consumption can be as much as about 40%.
  • the invention provides a vacuum pumping device for lowering the pressure of an enclosure, the device comprising a motor driving a multi-stage dry mechanical vacuum pump, each stage having an intake and an outlet, and the pump including pipes for interconnecting the stages in the circuit for pumping gas out from the enclosure.
  • the device includes fluid flow connection means that interconnect the stages so as to pass from a first configuration in which the stages are connected in parallel at least in pairs during a first pumping step, to a last configuration in which the stages are connected in series in a last pumping step, and passing via at least one intermediate configuration, during an intermediate pumping step, pumping speed being optimized in each current pressure range, and in which at least one stage is connected in parallel with at least one other stage, while at least one stage is connected in series with at least one other stage.
  • the fluid flow connection means may advantageously comprise valves controlled by electronic control means and inserted in the pipes.
  • the electronic control means actuate the valves to pass from one configuration to the following configuration in response to variation in the gas pressure inside the enclosure.
  • the gas pressure inside the enclosure is a reliable indicator of the pumping capacity of the vacuum pumping device in its current configuration, and it is possible to compare the speed curves of various configurations in order to select at all times the configuration that presents the best pumping capacity.
  • the electronic control means actuate the valves to pass from one configuration to the following configuration in response to variation in the power consumed by the motor of the pump.
  • the power consumed by the motor is also a suitable parameter that gives an indication about the optimum or non-optimum state of the current configuration of the stages, since the power consumed by the pumping device increases above some limit value after the maximum of the speed curve has been reached.
  • the electronic control means may actuate the valves to pass from one configuration to the following configuration after a predefined duration which is a function of the volume of the enclosure being pumped out. For a given volume of enclosure to be pumped out, it is possible by trial and error to determine the times at which it is necessary to switch from one configuration to the next in order to remain continuously in the configuration that optimizes the speed of the vacuum pumping device.
  • valves and the inter-stage pipes are integrated in the body of the vacuum pump.
  • the electronic control means may advantageously increase the velocity of the motor, and thus the velocity of the pump, above its nominal velocity, it being observed that the nominal velocity can be exceeded without exceeding the power limit since the low pressure stage, which is the stage that limits power, is in a zone of low compression during this step.
  • the electronic control means can put the vacuum pumping device into a low cost mode of operation either by reducing the velocity of rotation of its motor so as to provide pressure-maintaining pumping, or by connecting an additional pumping stage presenting a low speed to the outlet, likewise so as to maintain pressure.
  • the device has four stages that are connected in the following successive configurations during pumping:
  • the first and second stages are connected in parallel with each other forming a first pair of stages, the third and fourth stages are connected in parallel with each other forming a second pair of stages, and the two pairs of stages are connected in series on the gas-flow path;
  • the device has five stages that are connected in the following successive configurations during pumping:
  • the first, second, and third stages are connected in parallel forming a group of stages, the fourth and fifth stages are connected in parallel with each other forming a pair of stages, and the group of stages and the pair of stages are connected in series with each other on the gas-flow path;
  • the first and second stages are connected in parallel with each other forming a first pair of stages, the third and fourth stages are connected in parallel with each other, forming a second pair of stages, and the first and second pairs of stages are connected in series with each other and with the fifth stage;
  • the device has six stages that are connected in the following successive configurations during pumping:
  • the first, second, and third stages are connected in parallel forming a first group of stages
  • the fourth, fifth, and six stages are connected in parallel forming a second group of stages
  • the first and second groups of stages are connected in series with each other on the gas-flow path;
  • the first, second, and third stages are connected in parallel forming a group of stages, the third and fourth stages are connected in parallel with each other, forming a pair of stages, and the group of stages and the pair of stages are connected in series with each other, and with the sixth stage;
  • the first and second stages are connected in parallel with each other forming a pair of stages, and the third, fourth, fifth, and sixth stages are connected in series with one another, and with the pair of stages;
  • the device has six stages that are connected in the following successive configurations during pumping:
  • the first, second, and third stages are connected in parallel forming a first group of stages, the fourth, fifth, and six stages are connected in parallel, forming a second group of stages, and the first and second groups of stages are connected in series on the gas-flow path;
  • the first and second stages are connected in parallel with each other forming a first pair of stages
  • the third and fourth stages are connected in parallel with each other forming a second pair of stages
  • the fifth and sixth stages are connected in parallel with each other forming a third pair of stages
  • the first, second, and third pairs of stages are connected in series with one another;
  • the first and second stages are connected in parallel with each other forming a pair of stages, and the third, fourth, fifth, and sixth stages are connected in series with one another, and with the pair of stages;
  • the invention provides a vacuum pumping method using a multi-stage dry mechanical pump for lowering the pressure inside an enclosure, in which the stages of the pump are interconnected in a plurality of successive configurations to pass from a first configuration in which the stages are connected in parallel at least in pairs during a first pumping step, to a last configuration in which the stages are connected in series during a last pumping step, and passing via at least one intermediate configuration, each configuration being selected to optimize pumping speed in the current pressure range.
  • at least one intake stage is connected in parallel with at least one other intake stage and at least one outlet stage is connected in series with at least one other stage.
  • the velocity of the pump may be temporarily increased above its nominal velocity.
  • FIG. 1 is a diagram illustrating a prior art structure for a vacuum pumping device in which the multi-stage pump is of the Roots type, with four pumping stages in series;
  • FIG. 2 is a diagrammatic view of a vacuum pumping device in an embodiment of the present invention, again comprising four stages of the Roots type, the stages being interconnected in a first configuration;
  • FIG. 3 is a perspective view of the FIG. 2 pumping device shown partially open;
  • FIG. 4 is a flow diagram showing how the pump stages are interconnected in the first configuration of FIG. 2 ;
  • FIG. 5 is a diagram of the pumping device in the embodiment in FIG. 2 , in a second configuration
  • FIG. 6 is a flow diagram showing the way in which the pump stages are interconnected in the second configuration of FIG. 5 ;
  • FIG. 7 is a flow diagram showing how the pump stages are interconnected in a third configuration
  • FIG. 8 is a graph plotting the curve of the pumping speed of the device of FIGS. 2 to 7 as a function of the pressure in the enclosure being pumped out;
  • FIG. 9 is a graph plotting the curve of the electricity consumption of the pumping device of FIGS. 2 to 7 while lowering the pressure in an enclosure;
  • FIGS. 10A to 10 D are diagrams of a vacuum pumping device in an embodiment of the present invention that comprises five stages of the Roots type, shown in four successive configurations while lowering the pressure in the chamber;
  • FIGS. 11A to 11 E are diagrams of a vacuum pumping device in an embodiment of the present invention comprising six stages of the Roots type, in five successive configurations while lowering the pressure in the chamber;
  • FIGS. 12B and 12C show an alternative embodiment corresponding respectively to FIGS. 11B and 11C .
  • Such a device comprises a motor 1 which drives a multi-stage Roots type pump 2 that sucks in gas from an enclosure 100 via an intake 3 and exhausts the gas via an outlet 4 .
  • the pump 2 comprises four successive stages respectively 5 , 6 , 7 , and 8 , each having a stator stage respectively 5 a , 6 a , 7 a , and 8 a , and a double rotor stage respectively 5 b , 6 b , 7 b , and 8 b.
  • Each stage has its own intake respectively 5 c , 6 c , 7 c , and 8 c , and its own outlet respectively 5 d , 6 d , 7 d , and 8 d.
  • each inter-stage pipe 9 - 11 in that prior art pump connects the outlet of the preceding stage to the intake of the following stage.
  • the inter-stage pipe 9 connects the outlet pipe 5 d to the intake 6 c . This connection is not changed during the pumping process.
  • FIG. 2 there is shown a vacuum pumping device structure in an embodiment of the invention.
  • This embodiment reproduces the same general structure as a traditional multi-stage Roots pump of the kind shown in FIG. 1 , but applies adaptations that make it possible to modify the connections between the stages.
  • FIG. 2 there can be found the same main elements as in the pump of FIG. 1 , and these elements are identified by the same numerical references.
  • the inter-stage pipe 9 connects the outlet 5 d to the intake 6 c ; the inter-stage pipe 10 connects the outlet 6 d to the intake 7 c ; and the inter-stage pipe 11 connects the outlet 7 d to the intake 8 c.
  • a first bypass pipe 12 between the intake 5 c and the inter-stage pipe 9 a second bypass pipe 13 between the inter-stage pipe 9 and the inter-stage pipe 10 ; a third bypass pipe 14 between the inter-stage pipe 10 and the inter-stage pipe 11 ; and a fourth bypass pipe 15 between the inter-stage pipe 11 and the outlet 8 d , as can be seen in the figure.
  • FIG. 2 there can be seen four valves respectively 16 , 17 , 18 , and 19 .
  • the valve 16 is arranged to put the intake 6 c selectively into communication either with the bypass pipe 12 or with the inter-stage pipe 9 and the outlet 5 d .
  • the valve 17 is arranged to close the bypass pipe 13 selectively.
  • the valve 18 is arranged to put the intake 8 c into communication selectively either with the bypass pipe 14 or the inter-stage pipe 11 and the outlet 7 d .
  • the valve 19 is arranged to close the bypass pipe 15 , selectively.
  • valves 16 and 17 are mechanically coupled to each other by a longitudinal actuator rod engaged in the inter-stage pipe 9 and driven by an actuator 20 .
  • valves 18 and 19 are mechanically coupled to each other on a longitudinal rod driven by an actuator 21 .
  • the actuators 20 and 21 are lowered, and the valves 16 - 19 are lowered as shown in FIG. 2 .
  • the first and second stages 5 and 6 are connected in parallel with each other, forming a first pair of stages, and the third and fourth stages 7 and 8 are in parallel with each other, forming a second pair of stages.
  • the two pairs of stages are connected in series in the gas-flow path between the intake 3 and the outlet 4 .
  • the actuators 20 and 21 are controlled by an electronic controller 22 to which they are connected by lines 20 a and 21 a .
  • the electronic controller 22 comprises, for example, a processor associated with memories containing a program for appropriately powering the actuators 20 and 21 and ensuring that the valves 16 - 19 are appropriately positioned during the various operating steps implemented by the device, as described below.
  • the speed of the motor 1 is also controlled by the electronic controller 22 , and it is connected thereto by a line 1 a with a speed controller being disposed outside or inside the motor 1 or in the electronic controller 22 .
  • FIG. 3 shows the same elements as FIG. 2 , but in a three-dimensional representation. There can thus be seen the motor 1 and the pump 2 with its intake 3 and its outlet 4 . There can also be seen the two actuators 20 and 21 , the valves 16 and 18 , and the Roots-type rotors 5 b , 6 b , and 7 b of the respective stages 5 , 6 , and 7 . The outlet stage 8 is not visible.
  • FIG. 4 shows the configuration of the FIG. 2 stages, and thus between the intake 3 and the outlet 4 there can be seen the two stages 5 and 6 connected in parallel with their respective intakes 5 c and 6 c being connected to each other via the bypass pipe 12 , and their respective outlets 5 d and 6 d being connected to each other by the bypass pipe 13 .
  • the stages 7 and 8 are likewise connected in parallel, their respective intakes 7 c and 8 c being connected to each other by the bypass pipe 14 , and their respective outlets 7 c and 8 c being connected to each other by the bypass pipe 15 .
  • the two pairs 5 - 6 and 7 - 8 are connected to each other in series by the inter-stage pipe 10 on the path followed by the gas from the intake 3 to the outlet 4 .
  • This first configuration shown in FIGS. 2 to 4 having two pairs of parallel stages corresponds the first configuration given to the device during a first step of pumping out an enclosure.
  • the system is given a second configuration, during an intermediate pumping step E 2 .
  • the first and second stages 5 and 6 or “intake” stages remain connected in parallel with each other, while the third and fourth stages 7 and 8 or outlet stages are connected in series with each other.
  • the first pair of stages formed by the first and second stages 5 and 6 is connected in series with the third and fourth stages 7 and 8 .
  • the actuator 20 remains down while the actuator 21 is raised into an up position.
  • an enclosure 100 has a volume V of 1000 L, and that it is desired to evacuate it over a duration t of 45 seconds (s); in practice, it is desired to cause the pressure inside the enclosure to go down from a pressure p 1 of 1 atmosphere to a pressure p 2 of 0.1 millibars (mBar), for example.
  • the mean electric power required for emptying the volume is about 13 kW (see FIG. 9 ).
  • stage 5 has a speed S 1 of 400 m 3 /h
  • stage 6 has a speed S 2 of 300 m 3 /h
  • stage 7 has a speed S 3 of 300 m 3 /h
  • stage 8 has a speed S 4 of 200 m 3 /h. It is shown below that the mean power consumption remains below 10 kW.
  • the gas pressure inside the enclosure is taken down from 1 atmosphere to a pressure p 1 .
  • the vacuum pumping device is then in its configuration as shown in FIGS. 2 and 4 .
  • K0 is the compression ratio of the pump at a speed of zero.
  • the power consumption is greater in the high pressure stage. Power increases in each stage with decreasing pressure p 1 (in).
  • FIG. 8 plots the curve of pump speed as a function of pressure in the chamber being pumped out.
  • step E 1 the speed of the vacuum pumping device of the invention in the first configuration follows a curve A that presents a maximum.
  • FIG. 9 plots energy consumption for mechanically driving the pump in rotation as a function of the pressure in the enclosure.
  • energy consumption increases regularly following a curve B, and then drops suddenly at the pressure p 1 when the device is switched into its second configuration.
  • the pressure inside the enclosure is taken from a pressure p 1 to a pressure p 2 .
  • the parallel outlet stage 7 - 8 is split into series so as to reduce the power consumed by the high pressure stage.
  • the configuration of the device is changed again to take the pressure inside the enclosure down from a pressure p 2 to a pressure p 3 .
  • the configuration is then as shown in FIG. 7 , with all four stages 5 - 8 in series.
  • this configuration of the stages in series enables the compression ratio to be increased.
  • the velocity is increased by a coefficient Kn.
  • stage 7 works from 50 mBar to 250 mBar
  • curves A, C, and F characterize pumping with a mean speed close to 700 m 3 /h (curve G representing an ideal pump operating at 700 m 3 /h), whereas the largest stage of the pump provides only 400 m 3 /h.
  • the invention thus provides a saving in maximum electric power of 40% to 45%, and a saving in mean energy consumption of 20% to 25%.
  • the invention provides a saving in the nominal size of the pump of about 40%.
  • the example described relates to a pumping device having a four-stage Roots-type dry mechanical pump.
  • the invention is applicable in the same manner to pumping devices based on a dry mechanical pump having some other number of stages, it being possible for the number of stages to be greater than or equal to four.
  • FIG. 10 shows an example of successive configurations of a pumping device of the invention as pressure decreases, for a device that has five stages.
  • FIG. 10A there can be seen between the intake 100 and the outlet 101 , three stages 102 , 103 , and 104 connected in parallel, their respective intakes 102 c , 103 c , and 104 c being connected to each other by the bypass pipe 105 , their respective outlets 102 d , 103 d , and 104 d being connected to one another by the bypass pipe 106 .
  • the two stages 107 and 108 are likewise connected in parallel, their respective intakes 107 c and 108 c being connected to each other by the bypass pipe 109 , their respective outlets 107 d and 108 d being connected to each other by the bypass pipe 110 .
  • the two groups 102 - 103 - 104 and 107 - 108 are connected to each other in series by the inter-stage pipe 111 on the gas-flow path between the intake 100 and the outlet 101 .
  • This first configuration constitutes the configuration given to the device during a first step E 1 of pumping out an enclosure.
  • the system is given a second configuration in an intermediate pumping step E 2 .
  • the first and second stages 102 and 103 are connected in parallel with each other as are the third and fourth stages 104 and 107 .
  • the first pair of stages formed by the first and second stages 102 and 103 is connected in series with the second pair of stages formed by the third and fourth stages 104 and 107 , and also in series with the fifth stage 108 .
  • FIG. 10C A third configuration, used in an intermediate pumping step E 3 , is shown in FIG. 10C .
  • the first and second stages 102 and 103 are connected in parallel with each other, while the third, fourth, and fifth stages 104 , 107 , and 108 are connected in series with the first pair of stages formed by the first and second stages 102 and 103 .
  • the last pumping step E 4 has all five stages 102 , 103 , 104 , 107 , and 108 connected in series with each one another on the gas-flow path.
  • FIG. 11 shows an example of successive configurations for a pumping device of the invention while pressure is being decreased when the device has six stages.
  • FIG. 11A there can be seen between the intake 200 and the outlet 201 , three stages 202 , 203 , and 204 connected in parallel, their respective intakes 202 c , 203 c , and 204 c being connected to one another by the bypass ducts 205 , their respective outlets 202 d , 203 d , and 204 d being connected to one another by the bypass ducts 206 .
  • the three stages 207 , 208 , and 209 are likewise connected in parallel, with their respective intakes 207 c , 208 c , and 209 c being connected to one another by the bypass ducts 210 , their respective outlets 207 d , 208 d , and 209 d being connected to one another by the bypass ducts 211 .
  • the two groups 202 - 203 - 204 and 207 - 208 - 209 are connected to each other in series by the inter-stage pipe 212 on the gas-flow path between the intake 200 and the outlet 201 .
  • This first configuration shown in FIG. 11A constitutes the configuration given to the device in a first step E 1 of pumping out an enclosure.
  • FIG. 11B the system is given a second configuration in an intermediate pumping step E 2 .
  • the three first stages 202 , 203 , and 204 remain connected in parallel.
  • the fourth and fifth stages 207 and 208 are connected in parallel with each other.
  • the group 202 - 203 - 204 , the pair 207 - 208 , and the sixth stage 209 are connected in series.
  • FIG. 11C A third configuration for an intermediate pumping step E 3 is shown in FIG. 11C .
  • the first three stages 202 , 203 , and 204 are still connected in parallel.
  • the fourth, fifth, and sixth stages 207 , 208 , and 209 are connected in series with one another, and with the group 202 - 203 - 204 .
  • FIG. 11D A fourth configuration for an intermediate pumping step E 4 is shown in FIG. 11D .
  • the first and second stages 202 and 203 are connected in parallel with each other.
  • the third, fourth, fifth, and sixth stages 204 , 207 , 208 , and 209 are connected in series with one another and with the first pair of stages formed by the first and second stages 202 and 203 .
  • FIG. 12 shows an example of alternative configurations that could be used with a pumping device of the invention having six stages.
  • the first configuration is as shown in FIG. 11A and constitutes the configuration that is given to the pumping device during a first step E 1 of pumping out an enclosure.
  • FIG. 12B the system is given a second configuration in an intermediate pumping step E 2 .
  • the intake 300 and the outlet 301 there are the first two stages 302 and 303 connected in parallel, their respective intakes 302 c and 303 c being connected to each another by the bypass pipe 304 , their respective outlets 302 d and 303 d being connected to each other by the bypass pipe 305 .
  • the next two stages 306 and 307 are likewise connected in parallel, their respective intakes 306 c and 307 c being connected to each other by the bypass pipe 308 , while their respective outlets 307 d and 308 d are connected to each other by the bypass pipe 309 .
  • the last two stages 310 and 311 are likewise connected in parallel, their respective intakes 310 c and 311 c being connected to each other by the bypass pipe 312 , while their respective outlets 310 d and 311 d are connected to each other by the bypass pipe 313 .
  • the three pairs 302 - 303 , 306 - 307 and 310 - 311 are connected to one another in series by the inter-stage pipes 314 and 315 respectively on the gas-flow path between the intake 300 and the outlet 301 .
  • FIG. 12C A third configuration for an intermediate pumping step E 3 is shown in FIG. 12C .
  • the two first stages 302 and 303 are connected in parallel.
  • the third and fourth stages 306 and 307 are also connected in parallel.
  • the last two stages 310 and 311 are connected in series with the pairs 302 - 303 and 307 - 308 .
  • the fourth and fifth configurations are analogous to those shown in FIGS. 11D and 11E .

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
US11/396,574 2005-04-05 2006-04-04 Rapidly pumping out an enclosure while limiting energy consumption Abandoned US20060222506A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR0503352 2005-04-05
FR0503352A FR2883934B1 (fr) 2005-04-05 2005-04-05 Pompage rapide d'enceinte avec limitation d'energie

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US20060222506A1 true US20060222506A1 (en) 2006-10-05

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US (1) US20060222506A1 (fr)
EP (1) EP1710440A3 (fr)
JP (1) JP2006291952A (fr)
CN (1) CN100559028C (fr)
FR (1) FR2883934B1 (fr)

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AU2012254972B2 (en) * 2011-11-18 2015-07-02 Flow Control Llc. Rechargeable battery powered utility pump with series centrifugal pump configuration
US20180112666A1 (en) * 2015-06-26 2018-04-26 Leybold Gmbh Vacuum pump system
US20180149156A1 (en) * 2015-08-27 2018-05-31 Elivac Company, Ltd. (Shanghai) Modularized Integrated Non-Coaxial Multiple Chamber Dry Vacuum Pump
GB2558626A (en) * 2017-01-11 2018-07-18 Edwards Ltd A multiple stage vacuum pump and pump configuring method
US20190113036A1 (en) * 2016-03-30 2019-04-18 Leybold Gmbh Vacuum pump having a silencer
CN112594544A (zh) * 2020-12-11 2021-04-02 宜春市富锐气体有限责任公司 一种氩气生产的充灌排抽真空设备
US20210140430A1 (en) * 2017-06-17 2021-05-13 Leybold Gmbh Multi-stage rotary piston pump
US11078910B2 (en) 2017-04-07 2021-08-03 Pfeiffer Vacuum Pumping unit and use
US20210372404A1 (en) * 2019-01-10 2021-12-02 Raymond Zhou Shaw Power saving vacuuming pump system based on complete-bearing-sealing and dry-large-pressure-difference root vacuuming root pumps
US11320036B2 (en) 2019-09-23 2022-05-03 Ovg Vacuum Technology (Shanghai) Co., Ltd Transmission structure of motor connection of roots pump
US11326604B2 (en) 2018-04-16 2022-05-10 Edwards Limited Multi-stage vacuum pump and a method of differentially pumping multiple vacuum chambers
US11339783B2 (en) 2019-09-23 2022-05-24 OVG Vacuum Technology (Shanghai) Co., Ltd. Pump housing structure of three-axis multi-stage Roots pump
US11415133B2 (en) * 2018-02-02 2022-08-16 Zhongshan Tianyuan Vacuum Equipment Technology Co., Ltd Multi-stage dry roots vacuum pump
US11441564B2 (en) 2019-09-23 2022-09-13 OVG Vacuum Technology (Shanghai) Co., Ltd. Driving structure of three-axis multi-stage roots pump
US11608829B2 (en) 2019-10-10 2023-03-21 OVG Vacuum Technology (Shanghai) Co., Ltd. Structure of rotor connection of multi-axial multi-stage roots pump

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JP4820304B2 (ja) * 2007-01-18 2011-11-24 株式会社荏原製作所 真空ポンプユニット
FR2984423A1 (fr) * 2011-12-15 2013-06-21 Adixen Vacuum Products Dispositif de pompage et equipement de fabrication d'ecrans plats correspondant
JP5099573B1 (ja) * 2012-01-23 2012-12-19 有限会社スコットプランニング 複数の真空装置の省エネルギ−化を図る真空ポンプシステム
DE102012220442A1 (de) * 2012-11-09 2014-05-15 Oerlikon Leybold Vacuum Gmbh Vakuumpumpensystem zur Evakuierung einer Kammer sowie Verfahren zur Steuerung eines Vakuumpumpensystems
DE102013223556A1 (de) * 2013-11-19 2015-05-21 Oerlikon Leybold Vacuum Gmbh Vakuumpumpen-System sowie Verfahren zum Betreiben eines Vakuumpumpen-Systems
EP3094849A4 (fr) * 2014-01-15 2017-11-15 Eaton Corporation Procédé d'optimisation de performances d'un compresseur d'alimentation
FR3017425A1 (fr) * 2014-02-12 2015-08-14 Adixen Vacuum Products Systeme de pompage et procede de descente en pression dans un sas de chargement et de dechargement
EP3489516B1 (fr) * 2017-11-24 2021-09-01 Pfeiffer Vacuum Gmbh Pompe à vide
FR3094762B1 (fr) * 2019-04-05 2021-04-09 Pfeiffer Vacuum Pompe à vide de type sèche et installation de pompage
FR3128747A1 (fr) * 2021-11-03 2023-05-05 Pfeiffer Vacuum Pompe à vide multi-étagée

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Cited By (21)

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US8864476B2 (en) * 2011-08-31 2014-10-21 Flow Control Llc. Portable battery operated bilge pump
US8894389B2 (en) * 2011-08-31 2014-11-25 Flow Control Llc. Rechargeable battery powered utility pump with series centrifugal pump configuration
US20130052060A1 (en) * 2011-08-31 2013-02-28 Xylem Ip Holdings Llc Rechargeable battery powered utility pump with series centrifugal pump configuration
AU2012254972B2 (en) * 2011-11-18 2015-07-02 Flow Control Llc. Rechargeable battery powered utility pump with series centrifugal pump configuration
US20180112666A1 (en) * 2015-06-26 2018-04-26 Leybold Gmbh Vacuum pump system
US20180149156A1 (en) * 2015-08-27 2018-05-31 Elivac Company, Ltd. (Shanghai) Modularized Integrated Non-Coaxial Multiple Chamber Dry Vacuum Pump
US10570898B2 (en) * 2015-08-27 2020-02-25 Elivac Company, Ltd. (Shanghai) Modularized integrated non-coaxial multiple chamber dry vacuum pump
US20190113036A1 (en) * 2016-03-30 2019-04-18 Leybold Gmbh Vacuum pump having a silencer
US11274668B2 (en) * 2016-03-30 2022-03-15 Leybold Gmbh Vacuum pump having a silencer
GB2558626A (en) * 2017-01-11 2018-07-18 Edwards Ltd A multiple stage vacuum pump and pump configuring method
US11078910B2 (en) 2017-04-07 2021-08-03 Pfeiffer Vacuum Pumping unit and use
US20210140430A1 (en) * 2017-06-17 2021-05-13 Leybold Gmbh Multi-stage rotary piston pump
US11415133B2 (en) * 2018-02-02 2022-08-16 Zhongshan Tianyuan Vacuum Equipment Technology Co., Ltd Multi-stage dry roots vacuum pump
US11326604B2 (en) 2018-04-16 2022-05-10 Edwards Limited Multi-stage vacuum pump and a method of differentially pumping multiple vacuum chambers
US20210372404A1 (en) * 2019-01-10 2021-12-02 Raymond Zhou Shaw Power saving vacuuming pump system based on complete-bearing-sealing and dry-large-pressure-difference root vacuuming root pumps
US11815095B2 (en) * 2019-01-10 2023-11-14 Elival Co., Ltd Power saving vacuuming pump system based on complete-bearing-sealing and dry-large-pressure-difference root vacuuming root pumps
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US11441564B2 (en) 2019-09-23 2022-09-13 OVG Vacuum Technology (Shanghai) Co., Ltd. Driving structure of three-axis multi-stage roots pump
US11608829B2 (en) 2019-10-10 2023-03-21 OVG Vacuum Technology (Shanghai) Co., Ltd. Structure of rotor connection of multi-axial multi-stage roots pump
CN112594544A (zh) * 2020-12-11 2021-04-02 宜春市富锐气体有限责任公司 一种氩气生产的充灌排抽真空设备

Also Published As

Publication number Publication date
FR2883934B1 (fr) 2010-08-20
FR2883934A1 (fr) 2006-10-06
EP1710440A2 (fr) 2006-10-11
JP2006291952A (ja) 2006-10-26
EP1710440A3 (fr) 2008-02-06
CN1847660A (zh) 2006-10-18
CN100559028C (zh) 2009-11-11

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