US20060120898A1 - Starting method for a piston compressor and piston compressor - Google Patents

Starting method for a piston compressor and piston compressor Download PDF

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Publication number
US20060120898A1
US20060120898A1 US11/289,144 US28914405A US2006120898A1 US 20060120898 A1 US20060120898 A1 US 20060120898A1 US 28914405 A US28914405 A US 28914405A US 2006120898 A1 US2006120898 A1 US 2006120898A1
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US
United States
Prior art keywords
piston
resetting
starting
drive moment
piston compressor
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.)
Abandoned
Application number
US11/289,144
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English (en)
Inventor
Stefan Zeh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Diehl AKO Stiftung and Co KG
Original Assignee
Diehl AKO Stiftung and Co KG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Diehl AKO Stiftung and Co KG filed Critical Diehl AKO Stiftung and Co KG
Publication of US20060120898A1 publication Critical patent/US20060120898A1/en
Abandoned legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/02—Stopping, starting, unloading or idling control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2201/00—Pump parameters
    • F04B2201/02—Piston parameters
    • F04B2201/0201—Position of the piston
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2201/00—Pump parameters
    • F04B2201/12—Parameters of driving or driven means
    • F04B2201/1208—Angular position of the shaft
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2203/00—Motor parameters
    • F04B2203/02—Motor parameters of rotating electric motors
    • F04B2203/0207—Torque
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2203/00—Motor parameters
    • F04B2203/02—Motor parameters of rotating electric motors
    • F04B2203/0209—Rotational speed

Definitions

  • the invention relates to a method for starting a piston compressor.
  • the invention relates, furthermore, to a piston compressor operating according to the method.
  • a piston compressor conventionally has at least one piston which can be moved in a pressure cylinder by a motor in such a way that the volume of a compression space formed between the pressure cylinder and the piston is periodically expanded and compressed in the course of the piston movement.
  • a compressible fluid in particular a refrigerant such as R600a, for example, is sucked into the compression space through an inlet valve provided in the pressure cylinder.
  • the sucked-in fluid is compressed and expelled under increased pressure through an outlet valve of the pressure cylinder.
  • the piston position which identifies the transition from a compression phase into a subsequent expansion phase is designated below as the compression point.
  • that piston position which identifies the transition between an expansion phase and a subsequent compression phase is designated as the expansion point.
  • the designation “piston compressor” relates both to a reciprocating-piston compressor and to a rotary-piston or rolling-piston compressor.
  • a reciprocating-piston compressor is concerned, a piston is movable linearly in the pressure cylinder.
  • the piston of such a reciprocating-piston compressor is conventionally driven by a rotating eccentric.
  • a rotary-piston cylinder is concerned, the piston, by contrast, is driven in rotation directly via a drive shaft and rotates with respect to the pressure cylinder.
  • the rotary position of the drive shaft or of the eccentric is adopted below as a measure of the piston position, so that reference to a specific piston position of a reciprocating-piston compressor is also in the form of a given angle value.
  • the sequence of an expansion phase and of a subsequent compression phase, to which, as a rule, a full rotation of the drive shaft or of the eccentric through 360° corresponds, is designated as the work cycle of the piston compressor.
  • a load moment occurs which fluctuates periodically with the work cycle and which, as a rule, passes through a pronounced maximum (designated below as the load peak) in the course of the compression phase. It is customary to configure an electronically regulated piston compressor in such a way that the maximum drive moment of the motor undershoots the maximum value of the load moment occurring during the load peak.
  • the load peak is overcome by the inertia of the piston compressor, that is to say by the kinetic energy stored in a flywheel mass.
  • the piston position is designated below as the steady-state point.
  • a method for starting a piston compressor which includes during a resetting phase, driving a piston of the piston compressor in a direction of a compression point of a piston position by applying a resetting drive moment. Maintaining the resetting drive moment until the piston reaches a starting position by overstepping a steady-state point as a result of displacement of fluid out of a compression space, formed between the piston and a corresponding pressure cylinder, through at least one leakage point.
  • an acceleration phase accelerating the piston out of the starting position into an operational direction of rotation with a starting drive moment.
  • a resetting phase for driving the piston of the piston compressor in the direction of a compression point of the piston position by the application of a resetting drive moment, and for maintaining the resetting drive moment until, by overshooting a steady-state point, the piston has reached a starting position.
  • an acceleration phase following the reaching of the starting position the piston is then accelerated out of the starting position in an operational direction of rotation by a starting drive moment.
  • the outlet point which is used is, in particular, the piston/cylinder play always present as a consequence of construction in a piston compressor.
  • the resetting drive moment is preferably directed opposite to the operational direction of rotation, so that, during the resetting phase, the piston compressor is rotated backwards opposite to the operational direction of rotation.
  • This is expedient particularly when, as a result of the type of construction of the piston compressor, a lower load moment and/or a higher leakage rate occur(s) during backward rotation than during corresponding forward rotation.
  • the output or leakage rate and the profile of the load moment behaves, as a rule, symmetrically with respect to a reversal in the direction of rotation.
  • the piston may also be driven equivalently in the operational direction of rotation.
  • the starting position is preferably selected such that it lies in the vicinity of the compression point or slightly precedes the latter, as seen in the operational direction of rotation. Expediently, the starting position lies, in particular, in an angular range of +/ ⁇ 30° about the compression point.
  • the piston compressor contains a piston movable in a pressure cylinder by a drive system.
  • the drive system contains an electric motor active on the piston via a drive shaft and an electronic control unit activating the motor.
  • the control unit is in this case configured for activating the motor according to the method described above.
  • the control unit is in this case configured, in particular, for activating the motor during the resetting phase in such a way that the piston is driven in the direction of the compression point under the action of the resetting drive moment, and for maintaining the resetting drive moment until the piston has reached a starting position.
  • the control unit is configured, furthermore, to activate the motor during the acceleration phase in such a way that the piston is accelerated out of the starting position into the operational direction of rotation under the action of the starting drive moment.
  • FIGS. 1 to 4 are diagrammatic, sectional views of a piston compressor in four successive piston positions during the starting operation of the piston compressor according to the invention
  • FIG. 5 is a graph of a characteristic profile of a load moment occurring during the operation of the piston compressor according to FIG. 1 , as a function of the piston position;
  • FIG. 6 is a graph according to FIG. 5 showing the profile of the load moment during the starting operation.
  • FIGS. 1-4 there is shown a piston compressor 1 illustrated diagrammatically as a reciprocating-piston compressor.
  • the piston compressor 1 contains a piston 2 which is displaceable linearly (in a vertical direction according to FIG. 1 ) in a pressure cylinder 3 .
  • an electric motor 4 is provided, which, in particular, is configured as a permanent-magnet synchronous motor and is activated by an electronic control unit 5 .
  • the motor 4 acts via a drive shaft 6 , merely indicated, on a drive eccentric 7 which, in turn, is connected in an articulated manner to the piston 2 via a connecting rod 8 , so that the rotational movement of the drive eccentric 7 is converted into a linear oscillating movement of the piston 2 in a known way.
  • the pressure cylinder 3 and the piston 2 delimit the compression space 9 , into which an inlet 11 and an outlet 12 for a fluid F to be compressed issue on a cylinder bottom 10 , facing away from the piston 2 , of the pressure cylinder 3 .
  • the fluid F is preferably a refrigerant, for example R600a.
  • an inlet valve 13 and outlet valve 14 are provided, which respectively shut off in a fluid-tight manner or release the inlet 11 and the outlet 12 , depending on the valve position.
  • Each valve 13 or 14 is configured as a flap which is prestressed into a closed position of rest by an elastic force, in particular a spring, or due to the elastic configuration of the flap itself.
  • Each valve 13 or 14 opens and closes automatically, in the manner of a non-return valve, under the action of a corresponding pressure gradient of the fluid F.
  • the inlet valve 13 in this case opens when a sufficient under pressure prevails in the compression space 9 with respect to the inlet 11 .
  • the outlet valve 14 opens when a sufficient over pressure prevails in the compression space 9 with respect to the outlet 12 .
  • the volume of the compression space 9 varies as a function of piston position S.
  • the rotary or annular position of the drive shaft 6 and of the drive eccentric 7 connected fixedly in terms of rotation to the latter is adopted as a measure of the piston position S.
  • a change in the piston position S from 0° to 180° corresponds to an expansion phase E ( FIG.
  • a full rotation of the drive eccentric 7 that is to say a change in the piston position S from 0° to 360°, is designated as the work cycle of the piston compressor 1 .
  • the work cycle thus contains the expansion phase E and the subsequent compression phase K.
  • the load moment L varies periodically as a function of the piston position S.
  • the amount of the load moment L occurring during the expansion phase E is small, whereas, in the course of the compression phase K, the load moment L passes through a pronounced maximum which is designated below as the load peak P.
  • a maximum load moment L max is reached in the region of the load peak P, for example, in a piston position S ⁇ 270°.
  • the motor 4 is configured in such a way that a maximum drive moment A max capable of being exerted on the drive eccentric 7 is lower than the maximum load moment L max . Consequently, there is a piston position S, in which the load moment L just overshoots the maximum drive moment A max , so that the motor power is no longer sufficient for further compression.
  • the steady-state point S b occurs in the vicinity of the load peak P, that is to say, when the piston 2 is driven in the operational direction B, in a piston position S which slightly undershoots 270°.
  • the starting operation of the piston compressor 1 is accordingly divided into a resetting phase 15 ( FIG. 6 ) and a subsequent acceleration phase 16 ( FIG. 6 ).
  • the piston 2 is rotated backwards out of the initial piston position S I , opposite to the operational direction of rotation B, with a low drive moment, until, with regard to the piston position S, a starting position S IV ( FIG. 4 ) is reached.
  • the piston compressor 1 in this case passes through the piston positions S II and S III illustrated in FIGS. 2 and 3 .
  • the starting position S IV is selected in the vicinity of the compression point S k and in this case, in particular, between the steady-state points S b and S′ b , so that, during the resetting phase 15 , the steady-state point S′ b has to be overcome when the piston 2 is rotated backwards. Likewise, if the piston 2 were to be moved into the starting position S IV by forward rotation, the steady-state point S b would have to be overcome.
  • the steady-state point S′ b is overcome in that, during the resetting phase 15 , the motor 4 exerts a resetting drive moment A R which is also maintained precisely when the steady-state point S′ b is reached or overshot.
  • This is implemented in technical terms in that the stator field of the motor 4 is rotated backwards at a low angular speed for a predetermined time span.
  • output points of the compression space 9 which, as a consequence of construction, are formed, in particular, by the piston/cylinder play always present to some extent, are utilized in a controlled way.
  • fluid F FIG. 3
  • the volume of the compression space 9 is further reduced and the piston position S thereby approaches the compression point S k beyond the steady-state point S′ b .
  • the load peak P′ is virtually “tunneled through” in this way.
  • a leakage point which, if appropriate, connects the compression space 9 to the inlet 11 may also be utilized additionally or alternatively to the leakage or output points 17 formed by the piston/cylinder play. Additionally or alternatively to leakage points 17 obtained as a consequence of construction, an artificial leakage point, for example in the form of a thin bypass line circumventing the inlet valve 13 , may also be provided. This is expedient particularly when an escape of the fluid F into the environment is to be avoided.
  • the exact site of the starting position S IV depends slightly on the initial piston position S I .
  • Motor activation during the resetting phase 15 is in this case configured in such a way that the starting position S IV always lies in an angular range of +/ ⁇ 30° about the compression point S k and, in an initial piston position S I of approximately 180°, coincides substantially with the compression point S k .
  • the piston position S passes through an acceleration range 18 of more than 240°, in the course of which no increased load moment L occurs, with the result that the piston compressor 1 can absorb sufficient momentum to overcome the load peak P.
  • the long acceleration range 18 thus makes it possible for the motor 4 to be configured with a particularly low maximum drive moment A max , without the starting behavior of the piston compressor 1 being impaired.
  • the resetting phase 15 and the acceleration phase 16 may be executed directly one after the other in time. However, the resetting phase 15 and the acceleration phase 16 may also be executed separately from one another in time. In particular, there is optionally provision for carrying out the resetting phase 15 at the end of an operating phase of the piston compressor 1 , so that, during a subsequent operating phase, the piston compressor 1 is already in the starting position S IV from the outset and can be started immediately by the execution of the acceleration phase 16 . Alternatively to this, there is optionally provision for the method described above to be carried out only when a previously conducted attempt at immediate starting has failed because of an unfavorable initial piston position S I .
  • a resetting drive moment A R acting in the operational direction of rotation B may also be exerted.
  • the starting method described can also be applied equivalently to a rotary-piston compressor.
  • the method described can also be used equivalently in a piston compressor with a different type of electronically regulated motor, in particular a brushless direct-current motor (BLDC), an asynchronous motor, a reluctance motor, etc.
  • BLDC brushless direct-current motor
  • asynchronous motor a reluctance motor, etc.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Compressor (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
US11/289,144 2004-11-29 2005-11-29 Starting method for a piston compressor and piston compressor Abandoned US20060120898A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102004057467.7 2004-11-29
DE102004057467A DE102004057467B3 (de) 2004-11-29 2004-11-29 Startverfahren für einen Kolbenverdichter

Publications (1)

Publication Number Publication Date
US20060120898A1 true US20060120898A1 (en) 2006-06-08

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US11/289,144 Abandoned US20060120898A1 (en) 2004-11-29 2005-11-29 Starting method for a piston compressor and piston compressor

Country Status (7)

Country Link
US (1) US20060120898A1 (de)
EP (1) EP1662143B1 (de)
CN (1) CN1782387B (de)
AT (1) ATE434727T1 (de)
DE (2) DE102004057467B3 (de)
ES (1) ES2327133T3 (de)
PL (1) PL1662143T3 (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070085501A1 (en) * 2005-10-14 2007-04-19 Samsung Electronics Co., Ltd. Compressor and a driving method thereof
US20080031747A1 (en) * 2004-05-17 2008-02-07 Koninklijke Philips Electronics N.V. Reciprocating Pump With Reduced Noise Level
US20150048109A1 (en) * 2012-03-22 2015-02-19 Wuxi Little Swan Co., Ltd. Dosing Device Overcoming Change In Viscidity Of Detergent And Method For Controlling Same
WO2022109700A1 (en) 2020-11-25 2022-06-02 Embraco Indústria De Compressores E Soluções Em Refrigeração Ltda. Piston positioning processes of a reciprocating compressor

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102012006495A1 (de) * 2011-04-01 2013-01-24 Secop Gmbh Verfahren zum Starten einer Pumpe bei nicht konstantem Momentverlauf
CN106089668A (zh) * 2016-08-15 2016-11-09 无锡惠山泵业有限公司 一种高效节能泵

Citations (8)

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US4401419A (en) * 1979-09-21 1983-08-30 Electrolux Siegen Gmbh Motor-compressor
US4656376A (en) * 1985-06-15 1987-04-07 Danfoss A/S Motor-compressor unit with offset starting torque
US4726738A (en) * 1985-01-16 1988-02-23 Hitachi, Ltd. Motor-driven compressor provided with torque control device
US5388967A (en) * 1993-03-10 1995-02-14 Sullair Corporation Compressor start control and air inlet valve therefor
US5801500A (en) * 1995-03-18 1998-09-01 Danfoss A/S Motor/compressor combination having a control arrangement for starting the motor with asynchronous and then synchronous commutation
US5988994A (en) * 1997-10-21 1999-11-23 Global Cooling Manufacturing Company Angularly oscillating, variable displacement compressor
US6648604B1 (en) * 1998-06-05 2003-11-18 Carrier Corporation Short reverse rotation of scroll compressor at startup
US6781342B2 (en) * 2002-05-29 2004-08-24 Bristol Compressors, Inc. System and method for soft starting a three phase motor

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DE8702221U1 (de) * 1987-02-13 1987-04-09 Becker, Erich, 7812 Bad Krozingen, De
CN2143685Y (zh) * 1992-12-10 1993-10-13 郝雷 便于起动的少油低噪声空气泵
US6085533A (en) * 1999-03-15 2000-07-11 Carrier Corporation Method and apparatus for torque control to regulate power requirement at start up
DE10023523C1 (de) * 2000-05-13 2001-12-13 Vacuubrand Gmbh & Co Kg Anlaufsteuerung für eine Membran- und/oder Kolbenvakuumpumpe
DE10133861B4 (de) * 2001-07-12 2007-06-06 Netzsch-Mohnopumpen Gmbh Antriebssystem für Pumpen
CN1201082C (zh) * 2001-12-18 2005-05-11 乐金电子(天津)电器有限公司 可变容量压缩机的启动控制方法
CN2606201Y (zh) * 2003-02-19 2004-03-10 吴体胜 空压机无负荷起动装置

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4401419A (en) * 1979-09-21 1983-08-30 Electrolux Siegen Gmbh Motor-compressor
US4726738A (en) * 1985-01-16 1988-02-23 Hitachi, Ltd. Motor-driven compressor provided with torque control device
US4656376A (en) * 1985-06-15 1987-04-07 Danfoss A/S Motor-compressor unit with offset starting torque
US5388967A (en) * 1993-03-10 1995-02-14 Sullair Corporation Compressor start control and air inlet valve therefor
US5801500A (en) * 1995-03-18 1998-09-01 Danfoss A/S Motor/compressor combination having a control arrangement for starting the motor with asynchronous and then synchronous commutation
US5988994A (en) * 1997-10-21 1999-11-23 Global Cooling Manufacturing Company Angularly oscillating, variable displacement compressor
US6648604B1 (en) * 1998-06-05 2003-11-18 Carrier Corporation Short reverse rotation of scroll compressor at startup
US6781342B2 (en) * 2002-05-29 2004-08-24 Bristol Compressors, Inc. System and method for soft starting a three phase motor

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080031747A1 (en) * 2004-05-17 2008-02-07 Koninklijke Philips Electronics N.V. Reciprocating Pump With Reduced Noise Level
US8523015B2 (en) * 2004-05-17 2013-09-03 Koninklijke Philips N.V. Reciprocating pump with reduced noise level
US20070085501A1 (en) * 2005-10-14 2007-04-19 Samsung Electronics Co., Ltd. Compressor and a driving method thereof
US7477032B2 (en) * 2005-10-14 2009-01-13 Samsung Electronics Co., Ltd. Compressor and a driving method thereof
US20150048109A1 (en) * 2012-03-22 2015-02-19 Wuxi Little Swan Co., Ltd. Dosing Device Overcoming Change In Viscidity Of Detergent And Method For Controlling Same
US9783921B2 (en) * 2012-03-22 2017-10-10 Wuxi Little Swan Co., Ltd. Dosing device overcoming change in viscidity of detergent and method for controlling same
WO2022109700A1 (en) 2020-11-25 2022-06-02 Embraco Indústria De Compressores E Soluções Em Refrigeração Ltda. Piston positioning processes of a reciprocating compressor

Also Published As

Publication number Publication date
EP1662143A3 (de) 2008-11-19
EP1662143B1 (de) 2009-06-24
ATE434727T1 (de) 2009-07-15
EP1662143A2 (de) 2006-05-31
CN1782387B (zh) 2010-05-12
DE502005007559D1 (de) 2009-08-06
CN1782387A (zh) 2006-06-07
ES2327133T3 (es) 2009-10-26
PL1662143T3 (pl) 2010-01-29
DE102004057467B3 (de) 2006-08-24

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