US3778198A - Meshing rotary piston machine with an internal shaft - Google Patents

Meshing rotary piston machine with an internal shaft Download PDF

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Publication number
US3778198A
US3778198A US00271810A US3778198DA US3778198A US 3778198 A US3778198 A US 3778198A US 00271810 A US00271810 A US 00271810A US 3778198D A US3778198D A US 3778198DA US 3778198 A US3778198 A US 3778198A
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US
United States
Prior art keywords
passages
valve
control port
inlet
outlet
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.)
Expired - Lifetime
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US00271810A
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English (en)
Inventor
S Giversen
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Danfoss AS
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Danfoss AS
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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
    • F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
    • F04C14/02—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations specially adapted for several machines or pumps connected in series or in parallel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
    • F01C1/00—Rotary-piston machines or engines
    • F01C1/08—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing
    • F01C1/10—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
    • F01C20/00—Control of, monitoring of, or safety arrangements for, machines or engines
    • F01C20/08—Control of, monitoring of, or safety arrangements for, machines or engines characterised by varying the rotational speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
    • F01C21/00—Component parts, details or accessories not provided for in groups F01C1/00 - F01C20/00
    • F01C21/18—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet
    • F01C21/186—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet for variable fluid distribution
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/86638—Rotary valve
    • Y10T137/86646—Plug type
    • Y10T137/86654—For plural lines

Definitions

  • the invention relates to fluid pressure motors and pumps of the type having a gerotor displacement mechanism and an axial type of valve.
  • the casing has inlet and outlet ports and a speed and load control port.
  • the rotary valve has first and second sets of al ternately arranged passages with one set having the usual constant fluid communication with the casing outlet port.
  • the other set of'valve passages includes some passages in constant fluid communication with the casing inlet port and at least one passage in constant fluid communication with the casing control port.
  • a change over unit has a fluid supply inlet, a fluid exhaust outlet and a control outlet connected to the casing control port referred to above.
  • the change over unit has means for selectively and alternately connecting the control port to the supply inlet and exhaust outlet thereof.
  • the objects of the present invention is to provide a rotary piston machine of the initially stated kind which hasmore than onetransmission ratio.
  • this object is achieved by the use of a second toothed element. having an even number of teeth and by the provision of a change over device by means or which each second or each fourth of the valve openings in the-second part ofthe distributingvalve is optionally connectible to one of the unions, preferably the pressure side first union, and the intermediate valve openings are connectible to the other unlOll.
  • each second opening When each second opening is connected to the same union, the machine operates in the normal manner. If however, only each fourth valve opening is connected to one of the unions whilst the three intermediate valve openings are assigned to the other union, a new kind of operation is surprisingly achieved.'lf an engine is operated under constant external conditions (pressure-level and throughput), then it operates at approximately twice thespeed'and with half of the torque. The transmission varies inthe ratio 1 2. If the machine in question is a vehicleengine, its speed can be changed without the aid of a change'over gear. The same applies in the operation of axpump.
  • the toothed wheel constitutes the second toothed element and has six teeth.
  • only one chamber is connected to the pressure side each time. This chamber is located in the middle of the three otherwise effective pressure chambers, so that the chamber having the greatesteffective component influences the rotation of the toothed wheel. The same applies when this one chamber is connected to the low-pressure or intake side.
  • a simple construction is that in which each fourth valve opening inwthe second part of the distributing remaining valveiopenings, as required, to one or other of the unions. In this arrangement, only each fourth valve opening requires to be changed over.
  • valve openings in the second part of the distributing valve take the form of axial grooves in the periphery of a rotary slide, three axially staggered annular grooves are formed in the periphery of the rotary slide, the first of these being connected to one of the unions and being located on one side of the axial grooves, the second being connected to the other union and being located on the other side of the axial grooves and the third being connected to the change over device and being located on that side of the second annular groove remote from the axial grooves, and each fourth axial groove joins the first annular groove, and the axial grooves on each side of each said fourth axial groove joins the second annular groove, whilst bores in the rotary slide connect theremaining axialgrooves with the third annular groove. Since only each fourth axial groove has to be connected to the third annulargroove, the bores required for this can be comfortably provided in the rotary slide.
  • the change over device may be manually actuated.
  • the change over device is preferably constituted by a three-way valve which is actuated in dependence upon the drop in pressure in the machine. If the pressure drop in an engine is reduced as a result of a decrease in load, the engine automatically switches over to another kind of operation which permits a higher speed with lower torque, and vice versa.
  • the three-way valve has a plunger which'in a first position connects a pressure passage, and in the second position, a low-pressure passage to the change over valve openings, and which can bemoved from one of its positions to the other in dependence upon the pressure in a pressure chamber adjacent an end face of thevalve, from which chamber the piston can bedisplacedinto its other position, and if the pressure-chamber is connectible to the first or second union by way of a control valve and in dependence upon the position of a piston displaceable by the pressure drop in the machine, this piston overriding the associated valve openings with a lost motion action.
  • a lost motion an
  • control valve in the interior of the plunger of the three-way valve.
  • FIG. 1 contains two graphs showing how the change over operation is dependent upon pressure.
  • the machine of the invention is operated as an engine.
  • a pipe supplying pressurized fluid is therefore connected to a first union 1, and a discharge pipe to a second union 2.
  • the engine includes a toothed ring 3 (the first toothed element) having seven teeth, and a toothed wheel 4 having six teeth. Displacement chambers 5 are formed between the ring and the wheel.
  • a distributing valve 6 consists of a first part 7 connected to and rotating with the toothed ring 3, and a second part 8 connected to and rotating with the toothed wheel 4.
  • the valve-part 7 contains seven valve openings 9 which are evenly spaced around its periphery and each of which is connectible by a passage 10 to a displacement chamber 5.
  • the second valve part 8 contains twelve openings 11 which are divided into three groups a, b and c. Each fourth opening a is continuously connected through pipes 12 to the'pressure side first union 1.
  • the second group b consists of openings on either side of the openings 11a.
  • the valve openings l-lb arecontinuously connected through pipes 13 to the second union 2.
  • the third group 0 is formed by the remaining openings which are connected through pipes 14 to a change over device 15.
  • This change over device can occupy either of two positions. In the first position, openings of the group 0 are connected to the first union l.In the second position openings of the group c are connected to the second union 2.
  • the change-over device is actuated by way of a pulse line 16 in dependence .upon the pressure-drop in the engine.
  • valve .openings 11c are connected on the pressure side. They then act in the same manner as the valve openings 11a. This results in a machine of this kind operating in the normal way. If however the change over device is moved into its other position, only the valve openings lla are located on the pressure side, whereas all theother valve openings are connected to the discharge side. Then, only the discharge chamber 5a, indicated by hatching in FIG. 1, is supplied with pressurized-fluid. The instantaneous point of rotation M of the toothed wheel 4 is near the top tooth.
  • the fluid pressure obtaining in the chamber 5a therefore applies to the toothed wheel 4 a force that is substantially at right angles to the lever-arm that rotates the toothed wheel. Therefore, in contrast to what would be the case with pressurized fluid in the neighbouring chambers, the fluid in chamber 5a is effective with full force for the moment of rotation. Irrespective of the particular position of the toothed wheel 4 and of part 8 of the distributing valve, there is always only one displacement chamber 5a, filled with pressurized medium, present. This displacement chamber 5a also always occupies approximately the same position in relation to the instantaneous point of rotation M of the toothed wheel. Tests'have shown that in a control system of this kind the torque is approximately halved and the speed is raised to approximately twice the value.
  • the working part of the machine which is illustrated in FIG. 2, has a housing 17 which is closed at the lefthand end by a cover plate 18, and at the other end is extended by a spacer 19, the toothed ring 3 and the cover plate 20.
  • the various parts are interconnected by means of screw bolts 21.
  • the universal-joint shaft 24 has toothed heads which mesh with corresponding internal teeth in the main shaft 22 and the toothed wheel 4.
  • the housing 17 constitutes the first part 7, and the rotary shaft 23 the second part 8 of the distributing valve 6.
  • the valve openings 9, which are connectible to the displacement chambers 5 through the bored passages 10 in the housing 17 and in the spacer 19, are therefore provided at the inner periphery of abore in the housing.
  • the valve openings 11, in the form of axial grooves, are formed on the periphery of the rotary slide.
  • a first annular groove 25 is located to the right of the axial grooves 11 and is connected to a pipe 26.
  • a second annular groove 27 is located to the left of the axial grooves 11 and is connected to a pipe 28.
  • a third annular groove 29 is provided at that side of the second annular groove 27 remote from the axial grooves 11, and is connected to a pipe 30.
  • FIGS. 2 and 4 together illustrate a complete machine.
  • FIG. 4 illustrates a form of the change-over device 15.
  • This device has an outer casing 32 in which is inserted a sleeve 33 held at each of its ends by a plug 34 and 35.
  • the sleeve accommodates a displaceable plunger 36, in which a goove 37 enables an outlet opening 38, connected to the pipe 14, to be selectibly connected to an inlet chamber 39 or an inlet chamber 40.
  • the inlet chamber 39 is connected to the pipes 12 and 13 by way of a pipe 41 and non-return valves 42 and 43 respectively which open towards the chamber 39.
  • the higher pressure therefore always obtains in the inlet chamber 39 irrespective of whether the pressurized medium is supplied through the union 1 or the union 2.
  • the inlet chamber 40 is connected to the pipes 12 and 13 by way of a pipe 44 and two non return valves 45 and 46 respectively which close towards the inlet chamber 40.
  • the discharge pressure therefore always obtains in the inlet chamber 40, irrespective of whether the discharge pipe is connected to the union 1 or the union 2.
  • a chamber 47 containing a compression spring 48 is provided at one of the ends of the plunger 36.
  • the chamber 47 is connected to the pipe 44 and is therefore under discharge pressure.
  • a pressure chamber49 At the opposite end of the plunger 36 is a pressure chamber49 to which the supply pressure or the discharge pressure can be optionally admitted through a passage 50 incorporating two valve openings 51 and 52.
  • a control piston 53 which is displaceable in a bore of the plunger 36, thereby overcoming the force of a spring 54.
  • the bore is sealed by means of a resilient plug 55.
  • the supply pressure obtains in the chamber 56 as a result of its communicating with the pipe 41 by way of the pipe 57, and the discharge pressure obtains in the chamber 58 since it communicates with the inlet chamber 40.
  • the piston 53 undergoes lost motion relatively to the valve openings 51 and 52,'so that when the piston is displaced, one opening is only uncovered after the other has been closed for some time.
  • Fluid pressure apparatus comprising a casing having inlet and outlet ports, said casing having a speed and load control port, chamber forming means for forming expanding and contractingchambers, a valve having a first part with channels extending to said chambers, said valve having a continuously rotatable second part with first and second sets of alternately arranged passages, said first set of passages including some passages in constant fluid communication with said inlet port and at least one passage in constant fluid communication with said control port, said second set of passages being in constant fluid communication with said outlet port said control port being in selective communication with either the inlet or outlet port.
  • Fluid pressure apparatus including a change over unit having a fluid supply inlet and a fluid exhaust outlet, said unit having a control outlet connected to said corltrol port, said unit having means for selectively and alternately connecting said control port to said supply inlet and said exhaust outlet.
  • Fluid pressure apparatus according to claim 3 wherein said change over unit is actuated in response to a pressure drop change across said inlet and outlet ports.
  • Fluid pressure apparatus includes an internally toothed ring member and a cooperating externally toothed star member having fewer teeth than said ring member and being disposed eccentrically relative thereto.
  • Fluid pressure apparatus according to claim 5 wherein said star member has an even number of teeth and the alternate ones of said first set of valve passages are connected to said control port.
  • Fluid pressure apparatus according to claim 6 wherein said star member has six teeth.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Hydraulic Motors (AREA)
  • Multiple-Way Valves (AREA)
  • Rotary-Type Compressors (AREA)
  • Rotary Pumps (AREA)
US00271810A 1971-08-13 1972-07-14 Meshing rotary piston machine with an internal shaft Expired - Lifetime US3778198A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2140569A DE2140569C3 (de) 1971-08-13 1971-08-13 Steuervorrichtung für eine parallel- und innenachsige Rotationskolbenmaschine

Publications (1)

Publication Number Publication Date
US3778198A true US3778198A (en) 1973-12-11

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ID=5816627

Family Applications (1)

Application Number Title Priority Date Filing Date
US00271810A Expired - Lifetime US3778198A (en) 1971-08-13 1972-07-14 Meshing rotary piston machine with an internal shaft

Country Status (11)

Country Link
US (1) US3778198A (xx)
JP (1) JPS5119165B2 (xx)
AT (1) AT326487B (xx)
BE (1) BE785445A (xx)
DD (1) DD113380A5 (xx)
DE (1) DE2140569C3 (xx)
FR (1) FR2149845A5 (xx)
GB (1) GB1398779A (xx)
IT (1) IT959144B (xx)
NL (1) NL7211019A (xx)
SE (1) SE379231B (xx)

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892503A (en) * 1974-01-23 1975-07-01 Sperry Rand Corp Apparatus and method for multiple mode motor
US4480971A (en) * 1983-01-17 1984-11-06 Eaton Corporation Two-speed gerotor motor
US4697998A (en) * 1985-02-01 1987-10-06 Eaton Corporation Hydraulic motor having integral flow control capability
US4767292A (en) * 1987-07-20 1988-08-30 Trw Inc. Electrical commutation apparatus
US5017101A (en) * 1988-03-29 1991-05-21 Jeffrey White Selectively operated gerotor device
US5061160A (en) * 1990-03-14 1991-10-29 Trw Inc. Two-speed gerotor with spool valve controlling working fluid
US5071327A (en) * 1990-10-31 1991-12-10 Parker Hannifin Corporation Two speed gerotor motor with centrally located valve and commutator
US5137438A (en) * 1991-04-18 1992-08-11 Trw Inc. Multiple speed fluid motor
EP0931935A1 (en) 1998-01-23 1999-07-28 Eaton Corporation Gerotor motor and improved spool valve therefor
US6544018B2 (en) * 2000-08-28 2003-04-08 Eaton Corporation Hydraulic motor having multiple speed ratio capability
US20040062672A1 (en) * 2002-09-26 2004-04-01 Sauer-Danfoss Holding A/S Transition valving by means of non-return valves
US6827562B1 (en) * 2003-06-06 2004-12-07 Eaton Corporation Method of controlling shifting of two-speed motor
US20060280636A1 (en) * 2003-10-29 2006-12-14 Josef Bachmann Double or multiple pump
WO2008125106A1 (de) * 2007-04-12 2008-10-23 Sauer-Danfoss Aps Gerotormotor
CN100455825C (zh) * 2006-10-08 2009-01-28 镇江大力液压马达有限责任公司 高速配流摆线液压马达
US20100080721A1 (en) * 2008-09-30 2010-04-01 Qinghui Yuan Rotary fluid device with multi-level phase shift control
US20140271297A1 (en) * 2005-09-23 2014-09-18 Eaton Corporation Net-displacement control of fluid

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS534503U (xx) * 1976-06-30 1978-01-17
JPS5941033B2 (ja) * 1979-03-09 1984-10-04 株式会社トキメック 可変容量型流体変換装置
DE3152773A1 (de) * 1981-03-16 1983-05-05 Zaporozskij Kt I Selskochozyai Planetenhydromotor
SE464657B (sv) * 1987-03-04 1991-05-27 Stal Refrigeration Ab Reglersystem foer reglering av en rotationskompressors inre volymfoerhaallande
DE4407308C1 (de) * 1994-03-04 1995-08-17 Hydraulik Nord Gmbh Hydraulische Lenkeinrichtung mit Übersetzungsänderung
DE102014211624A1 (de) 2014-06-17 2015-12-17 Zf Friedrichshafen Ag Innenzahnradmotor mit Hohlradaussparung
CN109458383B (zh) * 2018-12-03 2021-03-30 浙江大学 一种重载的复合式步进执行机构

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3261235A (en) * 1963-12-03 1966-07-19 Lamina Inc Portable rotary machining appliance and apparatus
US3283723A (en) * 1965-07-09 1966-11-08 Germane Corp Rotary fluid pressure devices
US3586466A (en) * 1969-12-02 1971-06-22 Albin R Erickson Rotary hydraulic motor

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3261235A (en) * 1963-12-03 1966-07-19 Lamina Inc Portable rotary machining appliance and apparatus
US3283723A (en) * 1965-07-09 1966-11-08 Germane Corp Rotary fluid pressure devices
US3586466A (en) * 1969-12-02 1971-06-22 Albin R Erickson Rotary hydraulic motor

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892503A (en) * 1974-01-23 1975-07-01 Sperry Rand Corp Apparatus and method for multiple mode motor
US4480971A (en) * 1983-01-17 1984-11-06 Eaton Corporation Two-speed gerotor motor
US4697998A (en) * 1985-02-01 1987-10-06 Eaton Corporation Hydraulic motor having integral flow control capability
US4767292A (en) * 1987-07-20 1988-08-30 Trw Inc. Electrical commutation apparatus
US5017101A (en) * 1988-03-29 1991-05-21 Jeffrey White Selectively operated gerotor device
US5061160A (en) * 1990-03-14 1991-10-29 Trw Inc. Two-speed gerotor with spool valve controlling working fluid
US5071327A (en) * 1990-10-31 1991-12-10 Parker Hannifin Corporation Two speed gerotor motor with centrally located valve and commutator
WO1992008049A1 (en) * 1990-10-31 1992-05-14 Parker Hannifin Corporation Two speed gerotor motor with centrally located valve and commutator
US5137438A (en) * 1991-04-18 1992-08-11 Trw Inc. Multiple speed fluid motor
EP0931935A1 (en) 1998-01-23 1999-07-28 Eaton Corporation Gerotor motor and improved spool valve therefor
US6033195A (en) * 1998-01-23 2000-03-07 Eaton Corporation Gerotor motor and improved spool valve therefor
US6544018B2 (en) * 2000-08-28 2003-04-08 Eaton Corporation Hydraulic motor having multiple speed ratio capability
US20040062672A1 (en) * 2002-09-26 2004-04-01 Sauer-Danfoss Holding A/S Transition valving by means of non-return valves
US6884048B2 (en) * 2002-09-26 2005-04-26 Sauer-Danfoss (Nordborg) Transition valving by means of non-return valves
US6887054B2 (en) * 2002-09-26 2005-05-03 Sauer-Danfoss Aps Transition valving by means of non-return valves
US20040175283A1 (en) * 2002-09-26 2004-09-09 Sauer-Danfoss Holding A/S Transition valving by means of non-return valves
US6827562B1 (en) * 2003-06-06 2004-12-07 Eaton Corporation Method of controlling shifting of two-speed motor
US20040247473A1 (en) * 2003-06-06 2004-12-09 Eaton Corporation. Method of controlling shifting of two-speed motor
US8485802B2 (en) * 2003-10-29 2013-07-16 Gkn Sinter Metals Holding Gmbh Pump with multiple volume streams
US20060280636A1 (en) * 2003-10-29 2006-12-14 Josef Bachmann Double or multiple pump
US9377020B2 (en) * 2005-09-23 2016-06-28 Eaton Corporation Net-displacement control of fluid
US20140271297A1 (en) * 2005-09-23 2014-09-18 Eaton Corporation Net-displacement control of fluid
CN100455825C (zh) * 2006-10-08 2009-01-28 镇江大力液压马达有限责任公司 高速配流摆线液压马达
WO2008125106A1 (de) * 2007-04-12 2008-10-23 Sauer-Danfoss Aps Gerotormotor
US8292605B2 (en) * 2008-09-30 2012-10-23 Eaton Corporation Rotary fluid device with multi-level phase shift control
US20100080721A1 (en) * 2008-09-30 2010-04-01 Qinghui Yuan Rotary fluid device with multi-level phase shift control

Also Published As

Publication number Publication date
SE379231B (xx) 1975-09-29
JPS5119165B2 (xx) 1976-06-15
DE2140569A1 (de) 1973-02-22
ATA473672A (de) 1975-02-15
JPS4828871A (xx) 1973-04-17
DE2140569B2 (de) 1973-09-20
FR2149845A5 (xx) 1973-03-30
NL7211019A (xx) 1973-02-15
BE785445A (fr) 1972-10-16
GB1398779A (en) 1975-06-25
DD113380A5 (xx) 1975-06-05
AT326487B (de) 1975-12-10
DE2140569C3 (de) 1974-04-18
IT959144B (it) 1973-11-10

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