EP2596242A1 - Ensemble piston - Google Patents

Ensemble piston

Info

Publication number
EP2596242A1
EP2596242A1 EP11731270.2A EP11731270A EP2596242A1 EP 2596242 A1 EP2596242 A1 EP 2596242A1 EP 11731270 A EP11731270 A EP 11731270A EP 2596242 A1 EP2596242 A1 EP 2596242A1
Authority
EP
European Patent Office
Prior art keywords
piston
roller
piston unit
recess
unit according
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.)
Withdrawn
Application number
EP11731270.2A
Other languages
German (de)
English (en)
Inventor
Philip Nagel
David Breuer
Geoffrey Kermode
Khaled Tibari
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP2596242A1 publication Critical patent/EP2596242A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16JPISTONS; CYLINDERS; SEALINGS
    • F16J1/00Pistons; Trunk pistons; Plungers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/04Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
    • F04B1/0404Details or component parts
    • F04B1/0408Pistons
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/04Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
    • F04B1/10Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement the cylinders being movable, e.g. rotary
    • F04B1/107Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement the cylinders being movable, e.g. rotary with actuating or actuated elements at the outer ends of the cylinders
    • F04B1/1071Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement the cylinders being movable, e.g. rotary with actuating or actuated elements at the outer ends of the cylinders with rotary cylinder blocks

Definitions

  • the invention relates to a piston and a roller comprehensive piston unit for a radial piston machine according to the preamble of patent claim 1.
  • the document DE 40 37 455 C1 shows a radial piston machine with a plurality of cylinders, which are arranged in a star shape in a rotor. Each cylinder is assigned a piston unit.
  • the piston unit has a stepped piston, which is supported radially outwardly via a respective roller on a lift curve of the radial piston machine. Since the lift curve is formed as a stator and has a waveform, an oscillating stroke movement of the stepped piston is performed with a rotating rotor.
  • the rollers are circular cylindrical over their entire length.
  • a disadvantage of such piston units is the friction that arises between the stepped piston and the associated role. Furthermore, a high Hertzian pressure, which arises in particular at the end portions of the circular cylindrical rollers, is disadvantageous.
  • piston units in which a pressure relief is provided between a piston and a roller. It has a flat depression arranged on the piston in a contact area with the roller. This is acted upon by a piston passing through the channel with working pressure from the associated cylinder.
  • the length of a recess of such pressure relief is limited in cambered rollers, since the recess can extend only along the circular cylindrical portion of the roller.
  • the document DE 27 31 474 A1 shows a piston unit with pressure relief and with a hollow cylindrical roller, which has a comparatively thin and weak wall.
  • the interior of the roller is acted upon by working pressure of the associated cylinder.
  • the Hertzian pressure of the weakened roller is reduced with the lift curve.
  • a disadvantage of the latter piston unit is the device technical effort to reduce the Hertzian pressure.
  • the invention is based on the object to provide a piston unit with pressure relief, which offers a very large discharge force.
  • the Hertzian pressure should be reduced with little effort.
  • the piston unit according to the invention of a radial piston machine has a piston and a roller or a roller body which, apart from a chamfer or the like, has a circular-cylindrical jacket.
  • a hydrostatic pressure or force relief is provided, which forms a pressure field there.
  • the role has an end-face
  • the roller has two end approximately concentric recesses, which are each surrounded by an approximately concentric ring portion. Between the two weakened ring sections a main section of solid material is arranged.
  • the pressure relief has a shallow recess, which is arranged on the piston in the contact area.
  • the recess is connected via a channel with an inner end face or with a circumferential surface of the piston. These surfaces are working surfaces of the piston and therefore acted upon by working pressure.
  • the recess extends substantially over an entire length of the roller. This maximizes the pressure field and thus the unloading force. This is e.g. in the case of a radial piston engine improves its Anfahr fürsgrad.
  • the recess is slightly shorter than the shell of the roller, so that in each case a sealing area between the recess and the respective end face of the roller remains.
  • the recess is filled with plastic for setting a predetermined rigidity and a damping effect and for preventing any material fatigue of the associated end section.
  • the plastic is an elastomer.
  • a main section radially enlarged relative to a journal section is provided, which is longer along a rotational axis of the roller than transverse thereto.
  • the piston may have a core and a metallic sheath or a
  • Plastic sheath which has a reduced hardness compared to the core.
  • the core can take over stability and support functions of the piston, while the sheath can take over sealing functions relative to the cylinder and the roller.
  • a fitting tolerance of the cylinder is reduced with such a piston, whereby the manufacturing cost of the piston unit according to the invention is reduced.
  • the leakage and / or the friction between the piston and cylinder can be reduced, whereby the efficiency of the corresponding radial piston machine is improved.
  • Figure 1 shows a part of a radial piston machine in lateral section with a first embodiment of a piston unit according to the invention
  • Figure 2 shows a role of the first embodiment of the piston unit according to the invention in a view
  • Figures 3a-c a stepped piston according to a second embodiment of the piston unit according to the invention.
  • FIG. 1 shows a detail of a radial piston machine with a first exemplary embodiment of piston units 14, 16, 10 according to the invention in a side sectional view.
  • the radial piston engine has a circumferential wave-shaped lifting curve 1 and eight cylinders 6, 8 with corresponding piston units 14, 16, 10, of which only three are shown completely in FIG. 1 and two are partially shown.
  • the cylinders 6, 8 are arranged radially or star-shaped in a rotor 2, while the lifting cam 1 is formed on a lifting plate 4.
  • Rotor 2 and lifting disk 4 can rotate relative to each other.
  • a radial piston machine of the type shown is commonly used as a hydraulic motor, wherein the rotor can be attached via the shaft 5 or the lifting cam to the element to be driven.
  • Each cylinder 6, 8 has a main section 6 and on its side facing the shaft 5 a radially stepped back guide section. 8
  • Each piston unit 14, 16, 10 has a roller 10, which rolls upon rotation of the rotor 2 along the lifting cam 1 and, relative to a longitudinal axis 12, performs an oscillating stroke movement.
  • a roller 10 is mounted in each stepped piston 14, 16.
  • Each stepped piston has a main portion 14 and a spigot portion 16.
  • the main portion 14 of the stepped piston bears against the roller 10 and is received in the main portion 6 of the cylinder, while the spigot portion 16 of the stepped piston is received in the guide portion 8 of the cylinder.
  • a circumferential groove 18 is introduced, in which a slotted metallic sealing ring 34 is received.
  • the sealing ring 34 is shown on one of the piston units, while in the other piston units of the sealing ring is omitted to illustrate the groove 18.
  • FIG. 2 shows the roller 10 of the first embodiment of a piston unit according to the invention in a view.
  • a jacket 10c of the roller 10 is - apart from a respective chamfer 10d - circular cylindrical.
  • a provided on the main portion 14 of the stepped piston shallow recess of the pressure relief (not shown in Figure 2) along a rotational axis 36 of the roller 10 over the largest part of the jacket 10 c extend.
  • FIG. 3a shows a stepped piston of a second exemplary embodiment of a piston unit according to the invention in a view from below.
  • a main portion 314 is extended along a rotational axis 336 of the roller (not shown in Figure 3a) as compared to the first embodiment, so that the main portion 314 has a strongly rounded (in the broadest sense) rectangular shape.
  • a delivery or absorption volume of the stepped piston is increased in conjunction with a correspondingly shaped cylinder.
  • a small recess 330 which is subjected to pressure relief via a channel 328 with high pressure, divided into two sections.
  • the particular slope of the lift curve (see Figure 1) and the corresponding inclination of the application of force to the role of each of the two subregions of the recess 330 takes over a large part of the pressure relief.
  • the stepped piston according to FIGS. 3 a to 3 c has a core (not shown in greater detail) made of iron or a steel, which is surrounded by a sheath 338 of comparatively soft and elastic material, for example of a metal, but in particular of a plastic.
  • the core is overmolded with the plastic, which can be formed in a fairly simple manner, the desired outer shape of the piston.
  • the softer material can deform slightly under load, so that the load between the piston and rotor is distributed over a larger area.
  • the depressions 330 for the pressure relief of a roll can be produced already during injection molding of the plastic.
  • the rollers can run directly on the plastic.
  • Figure 3b shows a piston with a sheath 338 made of plastic in a side sectional view.
  • the sheath 338 also serves to
  • FIG. 3c shows the stepped piston of the second exemplary embodiment of a piston unit according to the invention in a lateral view.
  • a spigot portion 316 of the stepped piston has two recesses formed by respective flats, of which only one recess 316a is shown in FIG. 6c. They serve for the pressure medium connection of the two pressure chambers or work spaces formed between the stepped piston 314, 416 and an associated cylinder (not shown in FIGS.
  • a piston unit for a radial piston machine which has a piston and a roller or a roller body, which - apart from a chamfer or the like - has a circular cylindrical jacket.
  • a contact area between the piston and the roller is a hydrostatic pressure or force relief
  • the role has one or two end-side recesses. Through this recess (s), the role is assigned to

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Hydraulic Motors (AREA)
  • Reciprocating Pumps (AREA)
  • Rolls And Other Rotary Bodies (AREA)

Abstract

L'invention concerne un ensemble piston pour une machine à pistons radiaux, ledit ensemble comportant un piston et un rouleau ou un corps de rouleau ayant, mis à part un chanfrein ou similaire, une surface extérieure cylindrique circulaire. Une décharge de pression ou de force hydrostatique a lieu dans une zone de contact entre le piston et le rouleau, et y forme un champ de pression. Selon l'invention, le rouleau possède un ou deux évidements frontaux. Ce ou ces évidements affaiblissent légèrement le rouleau dans la partie d'extrémité associée, de sorte que la pression hertzienne y soit réduite.
EP11731270.2A 2010-07-23 2011-07-07 Ensemble piston Withdrawn EP2596242A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102010032056.0A DE102010032056B4 (de) 2010-07-23 2010-07-23 Kolbeneinheit
PCT/EP2011/003392 WO2012010262A1 (fr) 2010-07-23 2011-07-07 Ensemble piston

Publications (1)

Publication Number Publication Date
EP2596242A1 true EP2596242A1 (fr) 2013-05-29

Family

ID=44628407

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11731270.2A Withdrawn EP2596242A1 (fr) 2010-07-23 2011-07-07 Ensemble piston

Country Status (5)

Country Link
US (1) US9334956B2 (fr)
EP (1) EP2596242A1 (fr)
CN (1) CN103249948B (fr)
DE (1) DE102010032056B4 (fr)
WO (1) WO2012010262A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105781869A (zh) * 2015-01-13 2016-07-20 罗伯特·博世有限公司 活塞单元和流体静力的径向活塞机

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010015417A1 (de) * 2010-04-19 2011-10-20 Robert Bosch Gmbh Kolben für eine Radialkolbenmaschine
DE102012110564A1 (de) 2012-11-05 2014-05-08 Linde Hydraulics Gmbh & Co. Kg Hydrostatische Verdrängermaschine mit einer Rollenabstützung der Kolben
US9452535B2 (en) 2013-05-31 2016-09-27 National Oilwell Varco, L.P. Self-aligning pipe gripping assembly and method of making and using the same
FR3049990A1 (fr) * 2016-04-08 2017-10-13 Laurent Eugene Albert Machine hydrodynamique

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CS212800B2 (en) 1976-07-15 1982-03-26 Ivan J Cyphelly Delivery apparatus with hydrostatic torque transfer by cylindrical pistons
CH642147A5 (de) * 1979-05-18 1984-03-30 Glyco Antriebstechnik Gmbh Verdraengermaschine mit hydrostatischer drehmomentuebertragung mittels rollenkolben.
DE3919456A1 (de) * 1989-06-14 1990-12-20 Rexroth Mannesmann Gmbh Radialkolbenmotor
JPH03205019A (ja) * 1990-01-04 1991-09-06 Matsushita Electric Ind Co Ltd コーヒ豆等の粉砕器
DE4037455C1 (fr) * 1990-11-24 1992-02-06 Mannesmann Rexroth Gmbh, 8770 Lohr, De
SE503563C2 (sv) * 1991-06-25 1996-07-08 Haegglunds Denison Drives Ab Anordning vid hydraulkolvmotor
SE517873C2 (sv) * 1997-04-10 2002-07-30 Haegglunds Drives Ab Kolv till en hydraulisk radialkolvmotor samt hydraulisk radialmotor med sådan kolv
DE19747936A1 (de) * 1997-07-30 1999-02-04 Bosch Gmbh Robert Kolbenpumpe
DE10041318A1 (de) * 2000-08-23 2002-03-07 Mannesmann Rexroth Ag Hydraulische Radialkolbenmaschine
JP2007198518A (ja) * 2006-01-27 2007-08-09 Ntn Corp ころおよびころ軸受
DE102007004069A1 (de) * 2007-01-26 2008-07-31 Robert Bosch Gmbh Radialkolbenmaschine
DE102009028373A1 (de) * 2009-08-10 2011-02-17 Robert Bosch Gmbh Hochdruckpumpe

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2012010262A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105781869A (zh) * 2015-01-13 2016-07-20 罗伯特·博世有限公司 活塞单元和流体静力的径向活塞机
CN105781869B (zh) * 2015-01-13 2021-12-07 罗伯特·博世有限公司 活塞单元和流体静力的径向活塞机

Also Published As

Publication number Publication date
US20130228071A1 (en) 2013-09-05
DE102010032056A1 (de) 2012-01-26
WO2012010262A1 (fr) 2012-01-26
CN103249948A (zh) 2013-08-14
CN103249948B (zh) 2016-01-13
DE102010032056B4 (de) 2019-11-28
US9334956B2 (en) 2016-05-10

Similar Documents

Publication Publication Date Title
EP1886035B1 (fr) Palier pivotant a disques obliques
WO2007039384A1 (fr) Poussoir a galet
DE102010032056B4 (de) Kolbeneinheit
EP2561229A1 (fr) Piston pour une machine à pistons radiaux
WO2012034619A1 (fr) Machine à pistons axiaux
EP1553291A2 (fr) Machine a piston elevateur
WO2012010261A2 (fr) Unité piston
DE102010039269A1 (de) Kolbenpumpen für eine hydraulische Fahrzeugbremsanlage
DE102018208068A1 (de) Anschlussbaugruppe mit Speisepumpe und elastischem Element
DE102012206699A1 (de) Zahnradmaschine mit wannenartiger Vertiefung an der Außenoberfläche des Gehäuses
EP2567114B1 (fr) Palier excentrique
DE102012009794A1 (de) Hydrostatische Radialkolbenmaschine und Kolben für eine hydrostatische Radialkolbenmaschine
EP2078155B1 (fr) Dispositif de transport
EP3077656A1 (fr) Pompe à carburant
EP2464853B1 (fr) Pompe à haute pression
EP0903494B1 (fr) Pompe hydraulique
DE102012210199A1 (de) Stößelbaugruppe für eine Kraftstoffhochdruckpumpe sowie Kraftstoffhochdruckpumpe
DE102007004069A1 (de) Radialkolbenmaschine
EP2134966B1 (fr) Pompe, notamment pompe de carburant à haute pression
DE102014220384B4 (de) Kraftstoffhochdruckpumpe und Antriebswelle
EP0475109B1 (fr) Pompe à engrenages internes pour fluide hydraulique
DE10322501A1 (de) Drehkolbenpumpe
DE19810318B4 (de) Hydraulikmaschine
WO2008125106A1 (fr) Moteur à pistons rotatifs
DE102010028598A1 (de) Exzenterlager

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20130225

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20130724

RIN1 Information on inventor provided before grant (corrected)

Inventor name: NAGEL, PHILIP

Inventor name: KERMODE, GEOFFREY

Inventor name: BREUER, DAVID

Inventor name: TIBARI, KHALED