Classifications

• • 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
  • F04C29/04—Heating; Cooling; Heat insulation
• • 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
• • 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

Definitions

• Oil-injected compressor with means for oil temperature control
• the present invention relates to an oil-injected compressor, in particular an oil-injected mobile screw compressor, with a motor-driven compressor unit for generating compressed air, which cooperates with an oil circuit for lubrication, the oil reservoir is housed in a downstream ⁇ labscheider founded for separating the oil from the compressed air Means are provided for oil temperature control, which include a cooler with fan.
• the present invention is useful with other types of oil-injected compressors, such as scroll and vane compressors, in addition to oil-injected screw compressors.
• oil is injected by means of an oil circuit for lubrication in the field of moving compressor components and at their bearings in order to lubricate the one here existing, rotating at high speed bearings, and on the other also an inadmissible heating to prevent in the field of moving compressor components as a result of friction.
• the oil also serves to seal the air side against other areas of the compressor.
• the field of application of such oil-injected compressors extends thanks to the compactness mainly to mobile applications in rail vehicle construction or in the field of commercial vehicle construction.
• oil-injected compressors are also used in stationary compressed air supply systems.
• An oil-injected screw compressor essentially consists of a compressor unit with at least one pair of counter-rotating and interlocking cylindrical compressor screws.
• This compressor screw arrangement serves to generate compressed air in which air drawn in from one side from the atmosphere is converted into compressed air by continuous compression, which leaves the compressor unit via a spring-return outlet valve.
• the drive of the compressor screw assembly is carried out via a sealed out of the compressor unit to the outside drive shaft by means of a flanged here motor, usually an electric motor.
• the required high oil temperature is usually achieved quickly by a valve disposed in the oil control valve.
• the control valve regulates continuously and according to the operating conditions of the compressor divides the oil volume flow required for cooling in such a way between a radiator and bypass line, that always sets the same oil temperature.
• the fan wheel associated with the compressor and the radiator of the oil circuit is operated according to the prior art with maximum power by a rigid connection to the drive motor of the compressor unit. Only with separately driven radiator fan systems a simple start / stop operation is possible to prevent the cooling of the oil circuit at low oil temperature.
• the usually permanent and run at rated speed fan is used to maintain the operation of the compressor unit even in the worst case at high ambient temperatures, so that the maximum permissible oil temperature of 120 0 C is not exceeded.
• a disadvantage of this prior art is that as a result of the design of the fan to maximum requirement and maximum air flow, this is oversized in most of the time proportions of the operation of the compressor unit. This is usually a unnecessarily high Power requirement caused.
• the permanent fan drive causes a significant noise emission.
• the above-described control of the oil volume flow between radiator and bypass line causes regardless of the ambient temperature sets a predetermined control temperature in the oil reservoir. Since the maximum amount of water vapor in the ambient air significantly depends on its temperature, in this case, the level of the oil temperature is to be selected so high that even in the worst case, no condensate can fail in the compressor. As a result, the oil is exposed to increased aging. The same applies to all rubber and sealing parts of the compressor unit, which are exposed by the constant high oil temperature of a special load. Furthermore, the oil can not optimally fulfill its function as a gap seal in the actual compressor chamber when it is hot and thus less viscous, i. low viscosity, is. The volumetric efficiency drops with increasing oil temperature due to internal backflow.
• the invention includes the technical teaching that the means for controlling the oil temperature as adjusting device comprise a variable-speed drive for the fan, wherein a control device adjusts the speed of the fan as a function of the radiator from the ambient heat transferring heat from the cooler.
• the solution according to the invention is based on the recognition that the heating of the cooling air originating from the environment is approximately constant when passing through the cooler, but the ambient temperature can fluctuate greatly, so that the final temperature of the cooling air used for cooling also depends to a considerable degree on the ambient temperature is.
• the solution according to the invention thus makes it possible to link two controlled variables for the oil temperature with one another. On the one hand indirectly the oil temperature, which heats the cooling air at the radiator accordingly, taken as a control variable; On the other hand, the ambient temperature, which defines the basic level of the cooling air temperature, also flows in as a controlled variable. By linking these two control variables, the oil temperature can also be adapted to the current ambient temperature level, whereas according to the prior art, the oil temperature always remains at a constantly high level.
• the solution according to the invention allows a fan wheel operation which is always adapted to the needs. Since so far the fan was operated at maximum power, although considered by time proportion, this would be required only occasionally, resulting in particular in the sound emission significant improvements.
• the power requirement of the fan wheel is also much lower than in a permanently operated at the maximum point fan.
• the duty cycle on the speed of the fan wheel has a considerable impact. By dissipating in the stop phase of the compressor heat by cooling the compressor is used after a restart at the lowest possible speed of the fan wheel. As a result, even at low duty cycle, the necessary minimum temperature level is achieved quickly and, at the same time, significantly less sound is emitted than in the case of the solution known from the prior art.
• the solution according to the invention extends the maintenance intervals for oil and seals. In addition, the life of the compressor bearing is extended, resulting from the adjusted oil temperature.
• variable-speed drive of the fan wheel connected to the drive shaft constant speed viscous coupling is provided, which varies due to the prevailing during operation of the viscous coupling the slip accordingly.
• the drive shaft of the viscous coupling can be coupled in an advantageous manner with the shaft of the drive motor of the compressor unit.
• a viscous coupling in this case a conventional viscous coupling can be used, which noticeably reduces the slip with a simple bimetal from a certain temperature and also allows a soft adaptation of the slip to the temperature conditions due to the oil in the slippage space.
• control device adjusts the speed of the fan wheel in response to the determined by means of a temperature measuring device from the radiator to the heat coming from the environment cooling air heat.
• a temperature measuring device from the radiator to the heat coming from the environment cooling air heat.
• an electrical temperature sensor with appropriate electronics is required here.
• the measuring technology records the current ambient temperature at a suitable location.
• the control and regulation of the Lüfterradwindiere by means of inverter and drive the fan wheel which may for example be designed as a three-phase motor.
• the speed motor it is also conceivable to use a hydraulic motor for the variable-speed drive of the fan wheel, which can be acted upon with variable speed by an upstream hydraulic pump with pressure medium. In both cases eliminates the usual in the prior art control valve for controlling the oil temperature.
• the temperature measuring device or the viscous coupling is preferably to be arranged in the flow of the cooling air heated by the radiator between the latter and the fan wheel. At this point, a space-optimal accommodation can be realized. At the same time indirectly at this point the oil temperature, which heats the cooling air at the radiator, and on the other hand, the influence of the ambient temperature detectable and directly by a temperature sensor or indirectly by a corresponding temperature influence of the viscous coupling in a demand-driven speed control for the fan can be implemented.
• the cooler in addition to the above-described cooling of the oil circuit, can also be used for aftercooling of the compressed air leaving the oil separator device of the compressor. Thus eliminates a possibly separately provided for this cooler.
• the figure shows a schematic representation of an oil-injected compressor with means for controlling the oil temperature, here including a viscous coupling.
• an oil-injected compressor (screw compressor) essentially consists of a compressor unit 1, which is driven by an electric motor 2.
• an oil circuit Run 3 oil injected for lubrication In the area of the compressor screw assembly forming the compressor unit 1, an oil circuit Run 3 oil injected for lubrication. The oil required for lubrication, cooling and sealing purposes passes partially into the compressed air leaving the compressor unit 1 on the output side.
• the compressor unit 1 For separating the oil and the compressed air, the compressor unit 1 is followed by an oil separator 4.
• the oil reservoir 5 passes from the ⁇ labscheider issued 4 from the incoming oily compressed air by gravity separated oil, so that the output side of the oil separator 4 via the compressed air line 6 effluent compressed air is substantially free of oil.
• the compressed air line 6 is guided via a cooler 7 for further cooling of the compressed air.
• the cooler 7 also serves to cool the oil circulating in the oil circuit 3.
• the radiator 7 is supplied with the heated oil originating from the oil reservoir 5, which is again injected into the compressor unit 1 in a cooled manner by the radiator 7.
• Cooling air is drawn from the environment through the radiator 7 via a fan wheel 9 arranged adjacent to the radiator 7.
• the fan 9 is driven via the electric motor 2 with interposed viscous coupling 10.
• This arrangement forms in the oil temperature control a variable-speed drive for the fan 9, which represents the adjusting device insofar.
• the control device of the oil temperature control is embodied by the viscous coupling 10, which adjusts the rotational speed of the fan wheel 9 as a function of the heat transferred from the cooler 7 to the cooling air originating from the environment.
• the viscous coupling 10 is arranged in the range 1 1, which is suitable for detecting the ambient air heated by the oil temperature.
• the viscous coupling 10 varies due to the prevailing in this area 11 temperatures, the slip and thus the speed of the impeller 9, which thus ensures a demand-based oil temperature control.
• the invention is not limited to the preferred embodiment described above.
• the viscous coupling can also be replaced by a different type of control device, preferably by an electronic control device which detects the heat transferred from the environment with the help of a temperature sensor heat transferred and processed according to an electronic device at a predetermined set temperature control technology.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Applications Or Details Of Rotary Compressors (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Compressor (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

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• 2005
  • 2005-07-15 DE DE102005033084A patent/DE102005033084B4/de not_active Expired - Fee Related
• 2006
  • 2006-07-14 JP JP2008520807A patent/JP2009501290A/ja active Pending
  • 2006-07-14 EP EP06754724A patent/EP1907704B1/fr not_active Not-in-force
  • 2006-07-14 AT AT06754724T patent/ATE434133T1/de not_active IP Right Cessation
  • 2006-07-14 DE DE502006004009T patent/DE502006004009D1/de active Active
  • 2006-07-14 WO PCT/EP2006/006903 patent/WO2007009669A2/fr active Application Filing
  • 2006-07-14 US US11/995,581 patent/US20080206085A1/en not_active Abandoned

Non-Patent Citations (1)

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