US20020048523A1 - Rotary helical screw-type compressor - Google Patents
Rotary helical screw-type compressor Download PDFInfo
- Publication number
- US20020048523A1 US20020048523A1 US09/950,322 US95032201A US2002048523A1 US 20020048523 A1 US20020048523 A1 US 20020048523A1 US 95032201 A US95032201 A US 95032201A US 2002048523 A1 US2002048523 A1 US 2002048523A1
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- United States
- Prior art keywords
- housing
- rotor housing
- rotor
- gear
- rotors
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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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
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/02—Lubrication; Lubricant separation
- F04C29/025—Lubrication; Lubricant separation using a lubricant pump
-
- 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
-
- 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
- F04C27/00—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids
- F04C27/008—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids for other than working fluid, i.e. the sealing arrangements are not between working chambers of the machine
- F04C27/009—Shaft sealings specially adapted for pumps
-
- 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
- F04C18/14—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 toothed rotary pistons
- F04C18/16—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 toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
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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
- F04C2240/00—Components
- F04C2240/60—Shafts
- F04C2240/605—Shaft sleeves or details thereof
Definitions
- This invention pertains to a screw compressor of the type named in the preamble of claim 1 .
- the invention preferably, but not exclusively applies to a screw compressor used to produce a pressurized air stream for pneumatic transport of bulk materials.
- the invention applies to a screw compressor designed to be attached to a silo vehicle.
- Screw compressors are air compressors that work on the positive displacement principle. They have advantageous characteristics as compared to other compressors that make them especially suitable for the pneumatic transport of bulk materials. This applies in particular for so-called dry-running screw compressors in which the screw rotors, which are synchronized by means of a synchromesh gear, do not make any contact with each other nor with the surrounding housing parts. Thus, there is no need for lubrication in the compression space so that this space can be kept oil free, preventing any oil contamination of the pressurized air. Also, since the rotors run without touching one another, there is no wear in this area that could reduce their lifespan. No abrasion arises that can contaminate the conveyed air.
- screw compressors are suited mainly for the achievement of high compression ratios. They are insensitive to short term pressure increases that could be caused by pluggage of the pipelines carrying the pressurized air. Finally, they are lightweight and compact, which makes them suited especially for mobile use, for example in silo vehicles.
- the purpose of this invention is to construct a compressor housing with as much of a thermal separation of the oil supply container from the actual compressor space as possible overall.
- FIG. 1 a perspective view of the compressor with intake filter as seen from the side;
- FIG. 2 a vertical section through the compressor of FIG. 1;
- FIG. 3 a horizontal section through the compressor in the plane containing both rotor axes
- FIG. 4 another perspective representation of the compressor from below as seen from the suction side end with the intake housing and the oil container removed;
- FIG. 5 a detail of the perspective view of FIG. 1 with a modified embodiment form of the intake housing
- FIG. 6 an enlarged detail of the sectional representation of FIG. 2 in the area of the suction side rotor bearings
- FIG. 7 an enlarged detail of the sectional representation of FIG. 3 in the area of the pressure side rotor bearings.
- the housing of the compressor illustrated in FIG. 1- 4 is made up of the following main parts; a gear housing 1 , a rotor housing 3 , an inlet housing 4 , an intake housing 5 , and an oil container 7 .
- a gear housing 1 In the rotor housing 3 there are two rotors mounted on rotating bearings, namely a main runner 9 (toothed profile) and a secondary runner 11 (gapped profile). These rotors engage with one another by means of their screw-shaped teeth and tooth gaps, thus forming sealed chambers that move and shrink in the axial direction, thus compressing the intake air.
- the rotors are designed to run with their right end in FIG. 1- 3 being the suction side.
- air intake comes through inlet openings 13 provided at the end face of the rotor housing 3 .
- the air is conveyed in the axial direction to the left by the teeth and tooth gaps of the rotor pair as they engage with one another. It exits at the pressurized end of the rotors as compressed air at a pressure outlet 15 that is directed upward.
- the functioning principle of a screw compressor is known and is not explained here in more detail.
- the gear housing 1 is shaped like a disc-shaped pedestal.
- the drive shaft 17 of the compressor is mounted there in bearings 16 , 18 . Its shaft journal 17 a that extends out from the housing cover 49 is connected to a rotating drive unit that is not shown.
- the gear housing 1 also contains a set of drive gears that consists of a gear 19 fastened to the drive shaft 17 and a gear 21 that is fastened to the shaft journal 23 of the secondary runner 11 .
- This gear set transfers the rotation of the drive shaft 17 to the secondary runner 11 at a suitable gear ratio.
- the synchronizing gear set that makes sure the two rotors run synchronously is also kept in the gear housing 1 , i.e.
- This synchronizing gear set consists of gears 25 , 27 that engage together and are fastened to shaft journal 23 of the secondary runner and to shaft journal 29 of the main runner 9 .
- the pedestal or disc-shaped gear housing 1 has overhanging attachment feet 31 at its bottom support surface on both sides with holes 33 for fastening screws. These feet fasten the entire compressor to a suitable support, for example a vehicle.
- the rotor housing 3 is fastened to the gear housing 1 by means of a flange connection 37 such that it freely projects out from the gear housing 1 .
- the oil container 7 which has a flat box shape, is also attached to the gear housing 1 such that it freely projects out from it as well approximately parallel to the rotor housing 3 and beneath the same.
- the sidewalls of the oil container 7 are provided with cooling ribs 39 .
- Between the oil container 7 and the bottom of the rotor housing 3 is a relatively broad air gap 41 .
- An oil pump 45 is used to circulate the oil inside the gear housing 1 and to produce an oil mist.
- the pump surrounds the drive shaft 17 , which drives it.
- the housing of the oil pump 45 has a flange 47 projecting outward that centers the housing cover 49 fastened to the gear housing 1 .
- the oil pump 45 is attached to the gear housing 1 with 4 screws 51 (FIG. 3) and associated threaded holes.
- the ends of the suction side shaft journals 55 , 57 of the rotors 9 , 11 which extend beyond the bearings 53 , are provided with a tool interface for the attachment of a rotating tool.
- the tool interface consists of two flats 63 on which to place an open-end wrench.
- the tool interface can also take the form of a square end, a hexagonal end, a recessed hexagonal socket or similar.
- the shaft journals 55 , 57 containing the tool interface are easily accessible by removing a housing cover 65 fastened on top of the inlet housing 4 with screws.
- the inlet housing 4 that closes off the rotor housing 3 on the suction side and that has the inlet openings 13 is surrounded at a distance by a large-volume intake housing 5 (shown in FIG. 2 and FIG. 3 by dashed lines only).
- This intake housing is attached to a flange 67 of the rotor housing 3 by means of screws.
- this intake housing 5 which is directly attached to the rotor housing 3 , is an intake filter to filter the intake air and/or a muffler to dampen noise.
- the intake housing 5 contains a filter 6 made of a suitably porous or air-permeable filter material.
- the filter sits in an airflow path between an outer intake slot 69 and a feed-through slot 73 located along an interior separating wall 71 .
- the intake slot 69 and the feed-through slot are offset from one another such that as long a flow path as possible is formed for the air between the slots 69 , 73 and through the filter 6 .
- FIG. 5 a modified embodiment form of the intake housing 5 is shown.
- the air intake comes through the intake slot 69 and is redirected by the baffle wall 71 containing the feed-through slot 73 and flows through a muffler 75 that is made of suitable perforated sheeting. It then flows into the surrounding space of the housing cover 69 and flows through the inlet openings 13 into the interior of the rotor housing 3 .
- the intake housing 5 it contains both a filter as well as a muffler.
- An advantage of directly attaching the intake housing 5 containing a filter and/or a muffler to the rotor housing 3 in such a way that it surrounds the inlet housing 4 at a distance is that there is no need for a separate arrangement of a filter and/or muffler, nor is there need for a connecting line between it and the suction side of the compressor. This allows an especially simple, compact and robust arrangement.
- Another advantage is that the air intake into the intake housing 5 flows around and cools the exterior side of the inlet housing 4 containing the shaft journal bearings before it enters the interior of the rotor housing 3 through the inlet openings 13 . In this way, the suction side rotor bearings are effectively cooled.
- FIG. 6 shows an enlarged sectional representation of the bearing and seal of shaft journal 55 of rotor 9 inside the inlet housing 4 .
- the shaft journal 57 of the other rotor 11 is mounted and sealed in the same way.
- the shaft journal 57 with the tool interface (flats 63 ) is mounted in the center section of the inlet housing 4 , this section being designed similar to a hub, by means of a roller bearing 53 located between a shoulder of the shaft journal 57 and a retaining ring 83 engaged in an annular notch in the shaft journal.
- a race 85 is fastened to the shaft journals 57 next to the roller bearing 53 , preferably shrunk on.
- the race 85 which for example can be a common roller bearing race, is made of steel with a specially hardened peripheral surface. Two lip seals of a lip seal ring 87 cooperate with this race. This lip seal ring seals the interior of the rotor housing 3 off from the roller bearing 53 .
- a guard ring 89 between it and an internal shoulder 4 a of the inlet housing 4 .
- the internal perimeter of the guard ring sits opposite to the external surface of the race 85 with a very small gap, but does not touch.
- the guard ring 89 and the lip seal ring 87 are fixed against one another and against the inner shoulder 4 a of the inlet housing 4 in the recess of the housing, preferably glued in.
- the function of the guard ring 89 is as follows: during operation the compressor produces a pressurized air stream by intake air coming into the suction side and compressed exhaust air exiting at the pressure collar 15 .
- This pressurized air stream can be used for pneumatic transport of bulk powders, for example.
- a backlash of compressed air can occur from the pressure side to the suction side of the rotors, which presents the danger that particles of the powdered material carried by the air stream can travel into and out of the rotor housing 3 up to the shaft journals of the rotors.
- the guard ring 89 protects the lip seal ring 87 against this kind of material backlash when it occurs, preventing dust particles from reaching under the lip seals of the lip seal ring 87 and compromising the sealing effect.
- suction side bearing arrangement shown in FIG. 6 and described above has the further advantage in that these bearings can be removed from the shaft journal 57 without having to remove the rotor 9 or 11 or without having to change the precise setting of the rotors with respect to one another. Removing the bearing and seal arrangement from the shaft journal can be done in the following way:
- the housing cover 65 of the inlet housing 4 is removed so that the shaft journal 57 is accessible with its retaining ring 83 .
- the retaining ring 83 is removed.
- the screws connecting the inlet housing 4 to the rotor housing 3 are removed.
- the entire inlet housing 4 together with the roller bearings 53 , lip seal rings 87 and guard rings 89 contained in it can be removed. This allows the suction side roller bearings 53 , which are those parts that must be exchanged soonest due to the limited shelf life of their grease filling, to be easily changed out without having to change the rotors' 9 , 11 adjustment with respect to one another and to the housing or even to remove them at all.
- FIG. 7 shows the bearing and seal arrangement of the pressure side shaft journals 29 , 23 of the rotors 9 , 11 at the pressure end of the rotor housing 3 in a sectional representation similar to FIG. 3, but at a larger scale.
- the bearing and seal arrangement for shaft journal 29 of rotor 9 is described.
- the description for shaft journal 23 of rotor 11 is designed exactly the same.
- Shaft journal 29 is mounted in the pressure side end wall of the rotor housing 3 by means of two roller bearings 91 , 93 arranged next to one another.
- These roller bearings are designed as so-called angular contact ball bearings.
- Angular contact ball bearings commonly available commercially are ball bearings whose balls are held in place by the external race on one side and by the internal race on the other side of the ball's radial center plane.
- the two angular contact ball bearings 91 , 93 are arranged next to one another with mirror image symmetry. This type of arrangement of angular contact ball bearings is characterized in that it is completely free of play in the axial direction.
- a shaft nut 95 located on the shaft journal 29 fixes the angular contact ball bearings 91 , 93 on shaft journal 29 in the axial direction.
- the external race of angular contact ball bearing 93 sits against an inner shoulder 97 of the rotor housing 3 .
- a section of shaft journal 29 is located between angular contact ball bearing 93 and the rotor 9 .
- a race 101 is fastened to this section, being preferably shrunk on.
- This race 101 just as the race 85 described before in FIG. 6, is made of steel with a specially hardened perimeter surface.
- against the surface of the race 101 lie the lip seals of a lip seal ring 103 .
- This lip seal ring seals the compression space of the rotor housing 3 from the gear and bearing areas subjected to oil.
- the hardened and extremely precisely machined, e.g. polished, exterior surface of the race 25 results in an especially low-wear bearing surface for the lip seals of the lip seal ring 103 .
- a labyrinthine seal ring 105 that has a number of annular ribs next to one another on its inner perimeter that face the exterior surface of the race 101 with a very small gap but without touching it. These annular ribs form a labyrinthine gap together with this surface.
- the race 101 normally does not touch the labyrinthine sealing ring 105 , it is nevertheless advantageous for the race 101 to also extend along the area of the labyrinthine seal ring 105 .
- the labyrinthine gap seal is normally a non-contact seal, but under extreme operation conditions, contact can under certain conditions occur between the annular ribs of the labyrinthine seal ring 105 and the race 101 . If the race 101 were not present, grooves would be produced as a result on the shaft journal 29 so that it becomes damaged and the rotor 9 becomes unusable. Thanks to the existence of the race 101 , only the race 101 needs to be changed in this case so that the rotor 9 can be reused as it is otherwise free of damage.
- the ventilation channel 109 designed in the interior of the rotor housing 3 , which is the so-called lantern, runs from a point between the two shaft journals 29 , 23 of the rotors 9 , 11 downward and opens up at the bottom of the rotor housing 3 .
- the top of the oil container 7 with the cooling ribs 39 sits opposite to the opening of the lantern 109 at a distance.
- the oil container 7 blocks a straight access path to the opening of the lantern 109 from below.
- FIG. 4 shows a perspective view from below of the compressor with the oil container 7 removed so that the screw holes 44 for fastening the oil container 7 and the large connection opening 43 that allows the oil container to communicate with the gear housing are visible in the rear wall of the gear housing 1 .
- the intake housing 5 is removed from the suction side of the rotor housing 3 so that the view is free of the inlet housing 4 with its support ribs 14 and the inlet openings 13 leading to the interior of the rotor housing 3 .
- FIG. 4 also shows the opening of the lantern (ventilation channel) 109 at the bottom of the rotor housing 3 .
- the lantern ventilation channel
- shoulders 111 are provided on both sides of the opening of the lantern 109 at the bottom of the rotor housing 3 . These shoulders shield the opening of the lantern 109 against straight access from the side. These shoulders 111 can be formed from oil discharge channels. The opening of the lantern 109 is thus located at a protected position, straight access to which exists neither from below (due to the oil container 7 ) nor from the side (due to the shoulders 111 ). In this way, for example, high-pressure waterjets cannot be pointed directly at the opening of the lantern 109 when cleaning the compressor using high-pressure spray equipment. This would result in water entering the annular space 107 and thus into the area of the lip seal ring 103 and the labyrinthine seal ring 105 .
- the race 101 attached to shaft journal 29 also serves as a spacer that maintains a very exactly dimensioned gap between the pressure side rear face of the rotor 9 or 11 and the rear face 113 of the rotor housing 3 facing it.
- a deciding factor in the efficiency of the compressor is as small and as exactly defined as possible a gap at the pressure side rear face of the rotor 9 or 11 .
- the precise setting and maintenance of this gap is done by first preparing distance a between the rear face 113 facing rotor 9 and the bearing shoulder 97 for roller bearing 93 to a prescribed value with very tight tolerances when the rotor housing 3 is machined.
- Length b of race 101 which is used as a spacer between the roller bearing 97 and the rear face of rotor 9 , is also ground, with the same exacting tolerances, to a value that is in excess of distance a corresponding exactly to the width of the gap to be established between the rotor 9 and the rotor housing 3 .
- Adjusting the gap through the length difference of distances a and b is possible because angular contact ball bearings 91 , 93 are used in a symmetrical arrangement according to the invention. These angular contact ball bearings result in a bearing arrangement that is completely free of axial play, as mentioned above.
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Abstract
A screw compressor has a gear housing 1 from one side of which the rotor housing (3) containing the two screw rotors freely projecting outward. An oil supply container 7 is also located freely projecting out from the gear housing 1 approximately parallel to the rotor housing 3 and thermally separated from the rotor housing by means of an air gap. A ventilation channel 109 in the rotor housing 3 to vent the rotor shaft seals opens up to one point in the rotor housing that is protected against direct access by the oil supply container 7 mounted in front of it as well as by additional shoulders 111.
Description
- This invention pertains to a screw compressor of the type named in the preamble of
claim 1. The invention preferably, but not exclusively applies to a screw compressor used to produce a pressurized air stream for pneumatic transport of bulk materials. In particular, the invention applies to a screw compressor designed to be attached to a silo vehicle. - Screw compressors are air compressors that work on the positive displacement principle. They have advantageous characteristics as compared to other compressors that make them especially suitable for the pneumatic transport of bulk materials. This applies in particular for so-called dry-running screw compressors in which the screw rotors, which are synchronized by means of a synchromesh gear, do not make any contact with each other nor with the surrounding housing parts. Thus, there is no need for lubrication in the compression space so that this space can be kept oil free, preventing any oil contamination of the pressurized air. Also, since the rotors run without touching one another, there is no wear in this area that could reduce their lifespan. No abrasion arises that can contaminate the conveyed air. As a result of their operating characteristics, screw compressors are suited mainly for the achievement of high compression ratios. They are insensitive to short term pressure increases that could be caused by pluggage of the pipelines carrying the pressurized air. Finally, they are lightweight and compact, which makes them suited especially for mobile use, for example in silo vehicles.
- In a known screw compressor of this type, the compressor housing beneath the two rotors is designed as an oil pan. This has the disadvantage, among other things, in that a strong thermal coupling between the compressor space and the oil supply container arises so that the oil in the supply container is heated up to a considerable degree due to the heat produced in the compressor space as a result of the compression.
- The purpose of this invention is to construct a compressor housing with as much of a thermal separation of the oil supply container from the actual compressor space as possible overall.
- The solution of this objective according to the invention is given in
claim 1. The subordinate claims refer to advantageous embodiments of the compressor to achieve additional advantages. - The construction according to the invention, wherein the rotor housing and the supply container project out from the pedestal shaped drive housing separately and essentially parallel to one another, results in a significantly reduced heat transfer from the rotor housing to the oil supply container. This creates the advantageous ability of keeping the “lantern”, or the opening of a ventilation channel that leads away from the pressurized bearing area of the rotors, especially protected.
- One embodiment form of the compressor according to the invention is explained in more detail with the help of the drawings.
- FIG. 1 a perspective view of the compressor with intake filter as seen from the side;
- FIG. 2 a vertical section through the compressor of FIG. 1;
- FIG. 3 a horizontal section through the compressor in the plane containing both rotor axes;
- FIG. 4 another perspective representation of the compressor from below as seen from the suction side end with the intake housing and the oil container removed;
- FIG. 5 a detail of the perspective view of FIG. 1 with a modified embodiment form of the intake housing;
- FIG. 6 an enlarged detail of the sectional representation of FIG. 2 in the area of the suction side rotor bearings;
- FIG. 7 an enlarged detail of the sectional representation of FIG. 3 in the area of the pressure side rotor bearings.
- In all figures, the same parts, or corresponding parts, are shown with the same reference numbers.
- The housing of the compressor illustrated in FIG. 1-4 is made up of the following main parts; a
gear housing 1, arotor housing 3, aninlet housing 4, anintake housing 5, and anoil container 7. In therotor housing 3 there are two rotors mounted on rotating bearings, namely a main runner 9 (toothed profile) and a secondary runner 11 (gapped profile). These rotors engage with one another by means of their screw-shaped teeth and tooth gaps, thus forming sealed chambers that move and shrink in the axial direction, thus compressing the intake air. During operation, the rotors are designed to run with their right end in FIG. 1-3 being the suction side. Here, air intake comes throughinlet openings 13 provided at the end face of therotor housing 3. The air is conveyed in the axial direction to the left by the teeth and tooth gaps of the rotor pair as they engage with one another. It exits at the pressurized end of the rotors as compressed air at apressure outlet 15 that is directed upward. The functioning principle of a screw compressor is known and is not explained here in more detail. - The
gear housing 1 is shaped like a disc-shaped pedestal. Thedrive shaft 17 of the compressor is mounted there inbearings shaft journal 17 a that extends out from thehousing cover 49 is connected to a rotating drive unit that is not shown. Thegear housing 1 also contains a set of drive gears that consists of agear 19 fastened to thedrive shaft 17 and agear 21 that is fastened to theshaft journal 23 of thesecondary runner 11. This gear set transfers the rotation of thedrive shaft 17 to thesecondary runner 11 at a suitable gear ratio. The synchronizing gear set that makes sure the two rotors run synchronously is also kept in thegear housing 1, i.e. it is also kept on the pressurized side of therotors gears shaft journal 23 of the secondary runner and toshaft journal 29 of themain runner 9. - The pedestal or disc-
shaped gear housing 1 has overhangingattachment feet 31 at its bottom support surface on both sides withholes 33 for fastening screws. These feet fasten the entire compressor to a suitable support, for example a vehicle. - To provide continuous lubrication of the
drive gear gear oil pump 45. A required supply of oil is kept on hand in theoil container 7, which communicates with the interior of thegear housing 1.Seal arrangements 35 cooperate with theshaft journals rotors rotors drive gear gear rotors - As can be seen in FIG. 1 and FIG. 3, the
rotor housing 3 is fastened to thegear housing 1 by means of aflange connection 37 such that it freely projects out from thegear housing 1. Theoil container 7, which has a flat box shape, is also attached to thegear housing 1 such that it freely projects out from it as well approximately parallel to therotor housing 3 and beneath the same. The sidewalls of theoil container 7 are provided withcooling ribs 39. Between theoil container 7 and the bottom of therotor housing 3 is a relativelybroad air gap 41. With therotor housing 3 and theoil container 7 arranged in this way relative to one another and to thegear housing 1, the heat transfer, in particular through conduction, from therotor housing 3 to theoil container 7 is reduced to a minimum. This prevents the heat produced in therotor housing 3 during operation of the compressor due to the air compression from resulting in undesired heating of the oil supply in theoil container 7, even though theoil container 7 is directly connected to the gear housing. By directly fastening (flange connection) theoil container 7 to thegear housing 1, it can communicate with thegear housing 1 through alarge opening 43. Special oil lines are not necessary. - An
oil pump 45 is used to circulate the oil inside thegear housing 1 and to produce an oil mist. The pump surrounds thedrive shaft 17, which drives it. The housing of theoil pump 45 has aflange 47 projecting outward that centers thehousing cover 49 fastened to thegear housing 1. Theoil pump 45 is attached to thegear housing 1 with 4 screws 51 (FIG. 3) and associated threaded holes. - As a result of the arrangement of the
drive gear synchronization gear rotors bearings 53 for theshaft journals inlet housing 4 that closes off therotor housing 3 on the suction side. Theinlet openings 13 that lead to the interior of therotor housing 3 are designed in this inlet housing betweensupport ribs 14. Seal arrangements 61 that cooperate with theshaft journals bearings 53. These will be discussed below. - The ends of the suction
side shaft journals rotors bearings 53, are provided with a tool interface for the attachment of a rotating tool. In the embodiment example shown in FIG. 6, the tool interface consists of two flats 63 on which to place an open-end wrench. However, the tool interface can also take the form of a square end, a hexagonal end, a recessed hexagonal socket or similar. Theshaft journals housing cover 65 fastened on top of theinlet housing 4 with screws. - By attaching a rotating tool to one or both of the suction side shaft journals of the
rotors rotor housing 3 and between therotors drive shaft journals 17 a, since thedrive gear - The
inlet housing 4 that closes off therotor housing 3 on the suction side and that has theinlet openings 13 is surrounded at a distance by a large-volume intake housing 5 (shown in FIG. 2 and FIG. 3 by dashed lines only). This intake housing is attached to aflange 67 of therotor housing 3 by means of screws. In thisintake housing 5, which is directly attached to therotor housing 3, is an intake filter to filter the intake air and/or a muffler to dampen noise. In the embodiment form shown in FIG. 1, theintake housing 5 contains a filter 6 made of a suitably porous or air-permeable filter material. The filter sits in an airflow path between anouter intake slot 69 and a feed-throughslot 73 located along aninterior separating wall 71. Theintake slot 69 and the feed-through slot are offset from one another such that as long a flow path as possible is formed for the air between theslots - In FIG. 5, a modified embodiment form of the
intake housing 5 is shown. The air intake comes through theintake slot 69 and is redirected by thebaffle wall 71 containing the feed-throughslot 73 and flows through amuffler 75 that is made of suitable perforated sheeting. It then flows into the surrounding space of thehousing cover 69 and flows through theinlet openings 13 into the interior of therotor housing 3. It is also possible to design theintake housing 5 such that it contains both a filter as well as a muffler. - An advantage of directly attaching the
intake housing 5 containing a filter and/or a muffler to therotor housing 3 in such a way that it surrounds theinlet housing 4 at a distance is that there is no need for a separate arrangement of a filter and/or muffler, nor is there need for a connecting line between it and the suction side of the compressor. This allows an especially simple, compact and robust arrangement. Another advantage is that the air intake into theintake housing 5 flows around and cools the exterior side of theinlet housing 4 containing the shaft journal bearings before it enters the interior of therotor housing 3 through theinlet openings 13. In this way, the suction side rotor bearings are effectively cooled. - FIG. 6 shows an enlarged sectional representation of the bearing and seal of
shaft journal 55 ofrotor 9 inside theinlet housing 4. Theshaft journal 57 of theother rotor 11 is mounted and sealed in the same way. Theshaft journal 57 with the tool interface (flats 63) is mounted in the center section of theinlet housing 4, this section being designed similar to a hub, by means of aroller bearing 53 located between a shoulder of theshaft journal 57 and a retainingring 83 engaged in an annular notch in the shaft journal. Since no oil lubrication of any kind is to take place on the suction side of therotors roller bearing 53 as an encapsulated bearing with a lifetime grease filling so that it will never need any subsequent lubrication. Arace 85 is fastened to theshaft journals 57 next to theroller bearing 53, preferably shrunk on. Therace 85, which for example can be a common roller bearing race, is made of steel with a specially hardened peripheral surface. Two lip seals of alip seal ring 87 cooperate with this race. This lip seal ring seals the interior of therotor housing 3 off from theroller bearing 53. On the side of thelip seal ring 87 facing therotor housing 3 is aguard ring 89 between it and aninternal shoulder 4 a of theinlet housing 4. The internal perimeter of the guard ring sits opposite to the external surface of therace 85 with a very small gap, but does not touch. Theguard ring 89 and thelip seal ring 87 are fixed against one another and against theinner shoulder 4 a of theinlet housing 4 in the recess of the housing, preferably glued in. - The function of the
guard ring 89 is as follows: during operation the compressor produces a pressurized air stream by intake air coming into the suction side and compressed exhaust air exiting at thepressure collar 15. This pressurized air stream can be used for pneumatic transport of bulk powders, for example. In case of operational disruptions, a backlash of compressed air can occur from the pressure side to the suction side of the rotors, which presents the danger that particles of the powdered material carried by the air stream can travel into and out of therotor housing 3 up to the shaft journals of the rotors. Theguard ring 89 protects thelip seal ring 87 against this kind of material backlash when it occurs, preventing dust particles from reaching under the lip seals of thelip seal ring 87 and compromising the sealing effect. - The suction side bearing arrangement shown in FIG. 6 and described above has the further advantage in that these bearings can be removed from the
shaft journal 57 without having to remove therotor - After removing the
intake housing 5, thehousing cover 65 of theinlet housing 4 is removed so that theshaft journal 57 is accessible with its retainingring 83. The retainingring 83 is removed. Then, the screws connecting theinlet housing 4 to therotor housing 3 are removed. Now, theentire inlet housing 4 together with theroller bearings 53, lip seal rings 87 and guard rings 89 contained in it can be removed. This allows the suctionside roller bearings 53, which are those parts that must be exchanged soonest due to the limited shelf life of their grease filling, to be easily changed out without having to change the rotors' 9, 11 adjustment with respect to one another and to the housing or even to remove them at all. - FIG. 7 shows the bearing and seal arrangement of the pressure
side shaft journals rotors rotor housing 3 in a sectional representation similar to FIG. 3, but at a larger scale. Below, the bearing and seal arrangement forshaft journal 29 ofrotor 9 is described. The description forshaft journal 23 ofrotor 11 is designed exactly the same. -
Shaft journal 29 is mounted in the pressure side end wall of therotor housing 3 by means of tworoller bearings contact ball bearings shaft nut 95 located on theshaft journal 29 fixes the angularcontact ball bearings shaft journal 29 in the axial direction. The external race of angularcontact ball bearing 93 sits against aninner shoulder 97 of therotor housing 3. - A section of
shaft journal 29 is located between angularcontact ball bearing 93 and therotor 9. Arace 101 is fastened to this section, being preferably shrunk on. Thisrace 101, just as therace 85 described before in FIG. 6, is made of steel with a specially hardened perimeter surface. Against the surface of therace 101 lie the lip seals of a lip seal ring 103. This lip seal ring seals the compression space of therotor housing 3 from the gear and bearing areas subjected to oil. The hardened and extremely precisely machined, e.g. polished, exterior surface of therace 25 results in an especially low-wear bearing surface for the lip seals of the lip seal ring 103. - Furthermore, between the lip seal ring103 and the
rotor 9 is alabyrinthine seal ring 105 that has a number of annular ribs next to one another on its inner perimeter that face the exterior surface of therace 101 with a very small gap but without touching it. These annular ribs form a labyrinthine gap together with this surface. Although therace 101 normally does not touch thelabyrinthine sealing ring 105, it is nevertheless advantageous for therace 101 to also extend along the area of thelabyrinthine seal ring 105. The labyrinthine gap seal is normally a non-contact seal, but under extreme operation conditions, contact can under certain conditions occur between the annular ribs of thelabyrinthine seal ring 105 and therace 101. If therace 101 were not present, grooves would be produced as a result on theshaft journal 29 so that it becomes damaged and therotor 9 becomes unusable. Thanks to the existence of therace 101, only therace 101 needs to be changed in this case so that therotor 9 can be reused as it is otherwise free of damage. - Between the
labyrinthine seal ring 105 and the lip seal ring 103 is anannular breather space 107 that is connected to the atmosphere through a ventilation channel 109 (see FIG. 7 and FIG. 2). Theventilation channel 109 designed in the interior of therotor housing 3, which is the so-called lantern, runs from a point between the twoshaft journals rotors rotor housing 3. The top of theoil container 7 with the coolingribs 39 sits opposite to the opening of thelantern 109 at a distance. Theoil container 7 blocks a straight access path to the opening of thelantern 109 from below. - FIG. 4 shows a perspective view from below of the compressor with the
oil container 7 removed so that the screw holes 44 for fastening theoil container 7 and thelarge connection opening 43 that allows the oil container to communicate with the gear housing are visible in the rear wall of thegear housing 1. Further, in FIG. 4, theintake housing 5 is removed from the suction side of therotor housing 3 so that the view is free of theinlet housing 4 with itssupport ribs 14 and theinlet openings 13 leading to the interior of therotor housing 3. FIG. 4 also shows the opening of the lantern (ventilation channel) 109 at the bottom of therotor housing 3. As can be seen in FIG. 4, shoulders 111 are provided on both sides of the opening of thelantern 109 at the bottom of therotor housing 3. These shoulders shield the opening of thelantern 109 against straight access from the side. Theseshoulders 111 can be formed from oil discharge channels. The opening of thelantern 109 is thus located at a protected position, straight access to which exists neither from below (due to the oil container 7) nor from the side (due to the shoulders 111). In this way, for example, high-pressure waterjets cannot be pointed directly at the opening of thelantern 109 when cleaning the compressor using high-pressure spray equipment. This would result in water entering theannular space 107 and thus into the area of the lip seal ring 103 and thelabyrinthine seal ring 105. - As can be explained by means of FIG. 7, the
race 101 attached toshaft journal 29 also serves as a spacer that maintains a very exactly dimensioned gap between the pressure side rear face of therotor rear face 113 of therotor housing 3 facing it. A deciding factor in the efficiency of the compressor is as small and as exactly defined as possible a gap at the pressure side rear face of therotor rear face 113 facingrotor 9 and the bearingshoulder 97 forroller bearing 93 to a prescribed value with very tight tolerances when therotor housing 3 is machined. Length b ofrace 101 which is used as a spacer between theroller bearing 97 and the rear face ofrotor 9, is also ground, with the same exacting tolerances, to a value that is in excess of distance a corresponding exactly to the width of the gap to be established between therotor 9 and therotor housing 3. Adjusting the gap through the length difference of distances a and b is possible because angularcontact ball bearings housing shoulder 97 on the one hand and between the inner bearing ring ofroller bearing 93 and therace 101 on the other hand thereby act as axial reference surfaces that are free of play, a correspondingly exact adjustment of the rotor rear gap is obtained by the sufficiently exact machining of distance a of the housing shoulders and length b ofrace 101. The one-time adjustment of the rotor rear gap remains even with temperature changes since the influence of the different heat expansions of therotor housing 3 andrace 101 is negligibly small. The previous adjustment of the rotor rear gap required during installation of compressors of this type by inserting shim rings of various thicknesses corresponding to the manufacturers' tolerance fluctuations is eliminated.
Claims (4)
1. A screw compressor with two rotors mounted in a rotor housing (3) with parallel axes, that engage one another with screw-shaped teeth and tooth gaps, and that convey air during operation from a suction end toward a pressure end of the rotor housing (3) and in the process compress the air, with a gear housing (1) located at one end of the rotor housing (3) in which a drive shaft (17) is mounted with drive gears (19, 21) for the rotors (9, 11) and in which oil lubrication is provided for the drive gears, and
with a synchronizing gear (25, 27) that couples the rotors (9, 11) to run together in opposite directions synchronously without touching,
characterized in that the gear housing 1 has the form of a disc-shaped pedestal and is provided with means (31, 33) to fasten the gas housing 1 to a support,
that the rotor housing (3) freely projects out from the gear housing (1),
that an oil supply container (7) that communicates with the gear housing (1) freely projects out from the gear housing (1) essentially parallel to the rotor housing (3), wherein between the rotor housing (3) and the oil supply container (7) is an air gap (41) that results in a thermal separation,
that in a sealing arrangement (103, 105) that seals the pressure side shaft journals (23, 29) of the rotors (9, 11) in the rotor housing (3) there is a breather space (107) that is connected to the atmosphere via a ventilation channel (109) designed into the rotor housing (3),
and that the ventilation channel (109) opens up to the side of the rotor housing (3) facing the oil supply container (7) so that it is shielded against direct access by the oil supply container (7) mounted in front of it.
2. A screw compressor according to claim 1 , wherein the oil supply container (7) is provided with cooling ribs (39) on its exterior sides.
3. A screw compressor according to claim 1 , wherein shoulders (111) are designed into the rotor housing (3) on both sides of the opening of the ventilation channel (109) that shield the opening of the ventilation channel (109) against access from the side.
4. A screw compressor according to claim 1 wherein the gear housing (1) is closed off by a housing cover (49) on the side facing away from the rotor housing (3) and containing a bearing (16) for the drive shaft (17), and that in the gear housing (1) an oil pump (45) is provided to circulate and spray lubricating oil, said pump having an annular flange (47) that extends outward and is used to center the housing cover (49).
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE29904409 | 1999-03-10 | ||
DE29904409U DE29904409U1 (en) | 1999-03-10 | 1999-03-10 | Screw compressor |
DE29904409.2 | 1999-03-10 | ||
PCT/EP2000/002151 WO2000053932A1 (en) | 1999-03-10 | 2000-03-10 | Rotary helical screw-type compressor |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2000/002151 Continuation WO2000053932A1 (en) | 1999-03-10 | 2000-03-10 | Rotary helical screw-type compressor |
Publications (2)
Publication Number | Publication Date |
---|---|
US20020048523A1 true US20020048523A1 (en) | 2002-04-25 |
US6416302B1 US6416302B1 (en) | 2002-07-09 |
Family
ID=8070664
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/950,322 Expired - Fee Related US6416302B1 (en) | 1999-03-10 | 2001-09-10 | Rotary helical screw-type compressor having a thermally separated oil supply container |
Country Status (5)
Country | Link |
---|---|
US (1) | US6416302B1 (en) |
EP (1) | EP1163452B1 (en) |
AT (1) | ATE267344T1 (en) |
DE (2) | DE29904409U1 (en) |
WO (1) | WO2000053932A1 (en) |
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US20080112832A1 (en) * | 2006-11-10 | 2008-05-15 | Eisuke Kato | Hermetic screw compressor |
US20130280109A1 (en) * | 2010-09-23 | 2013-10-24 | Michael J. Lucas | Modular discharge silencer for vehicle-mounted compressor |
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WO2017221180A1 (en) | 2016-06-21 | 2017-12-28 | Golden Renewable Energy, LLC | Char separator and method |
US10233393B2 (en) | 2016-07-08 | 2019-03-19 | Golden Renewable Energy, LLC | Heated airlock feeder unit |
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US10345048B2 (en) | 2016-05-12 | 2019-07-09 | Golden Renewable Energy, LLC | Cyclonic condensing and cooling system |
US10436525B2 (en) | 2016-05-12 | 2019-10-08 | Golden Renewable Energy, LLC | Cyclonic cooling system |
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KR100996016B1 (en) * | 2000-09-20 | 2010-11-22 | 밀리포어 코포레이션 | Polynucleotide |
JP3796210B2 (en) * | 2002-11-01 | 2006-07-12 | 株式会社神戸製鋼所 | Screw compressor |
US6858067B2 (en) * | 2002-11-12 | 2005-02-22 | Perry Equipment Corporation | Filtration vessel and method for rotary gas compressor system |
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US8342829B2 (en) * | 2005-12-08 | 2013-01-01 | Ghh Rand Schraubenkompressoren Gmbh | Three-stage screw compressor |
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US20090129956A1 (en) * | 2007-11-21 | 2009-05-21 | Jean-Louis Picouet | Compressor System and Method of Lubricating the Compressor System |
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WO2023237955A1 (en) * | 2022-06-09 | 2023-12-14 | Atlas Copco Airpower, Naamloze Vennootschap | Housing for housing a gearbox of a rotary screw compressor. |
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JPS6293491A (en) * | 1985-10-21 | 1987-04-28 | Hitachi Ltd | Screw compressor |
JP2511870B2 (en) * | 1986-03-20 | 1996-07-03 | 株式会社日立製作所 | Screen-vacuum pump device |
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US5795136A (en) * | 1995-12-04 | 1998-08-18 | Sundstrand Corporation | Encapsulated rotary screw air compressor |
DE29807796U1 (en) * | 1998-04-30 | 1999-09-09 | GHH-RAND Schraubenkompressoren GmbH & Co. KG, 46145 Oberhausen | Sealing arrangement for a shaft journal of a dry-running rotary screw compressor |
-
1999
- 1999-03-10 DE DE29904409U patent/DE29904409U1/en not_active Expired - Lifetime
-
2000
- 2000-03-10 WO PCT/EP2000/002151 patent/WO2000053932A1/en active IP Right Grant
- 2000-03-10 EP EP00922512A patent/EP1163452B1/en not_active Expired - Lifetime
- 2000-03-10 DE DE50006496T patent/DE50006496D1/en not_active Expired - Lifetime
- 2000-03-10 AT AT00922512T patent/ATE267344T1/en not_active IP Right Cessation
-
2001
- 2001-09-10 US US09/950,322 patent/US6416302B1/en not_active Expired - Fee Related
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US20080112832A1 (en) * | 2006-11-10 | 2008-05-15 | Eisuke Kato | Hermetic screw compressor |
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US9657732B2 (en) * | 2010-09-23 | 2017-05-23 | Ingersoll-Rand Company | Modular discharge silencer for vehicle-mounted compressor |
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Also Published As
Publication number | Publication date |
---|---|
DE29904409U1 (en) | 2000-07-20 |
DE50006496D1 (en) | 2004-06-24 |
EP1163452B1 (en) | 2004-05-19 |
WO2000053932A1 (en) | 2000-09-14 |
US6416302B1 (en) | 2002-07-09 |
ATE267344T1 (en) | 2004-06-15 |
EP1163452A1 (en) | 2001-12-19 |
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