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
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
  • F04B1/20—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
  • F04B1/2014—Details or component parts
  • F04B1/2021—Details or component parts characterised by the contact area between cylinder barrel and valve plate
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
  • F05C2203/00—Non-metallic inorganic materials
  • F05C2203/08—Ceramics; Oxides
  • F05C2203/0804—Non-oxide ceramics
  • F05C2203/0808—Carbon, e.g. graphite
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
  • F05C2253/00—Other material characteristics; Treatment of material
  • F05C2253/12—Coating

Definitions

• DE 102 23 844 A1 describes an axial piston machine with a control plate and a cylinder drum sliding on the control plate. On the paired, mutually rubbing surfaces, a plastic layer is arranged on one side and a carbon-containing layer on the other side.
• the areas of the facing surfaces of the control plate and the cylinder drum are subjected to increased loads. This includes the notches normally present to avoid rapid pressure fluctuations at the control ports of the control plate.
• the mutually facing surfaces are also claimed by a falling back of the cylinder drum or the pressure plate on the control plate.
• the axial piston machine according to the invention with the features of claim 1 has the advantage of increased wear resistance, in particular against beating loads of successive sliding parts, against cavitation and against the biaxial load.
• the axial piston machine according to the invention is easier to manufacture and can be operated except with water with oil-containing fluids.
• the measures carried out in the dependent claims relate to advantageous developments of the axial piston according to the invention.
• the other, not coated with the layer sliding side consists of hardened by nitriding steel.
• the carbon layer opposite sliding side can be made simplified.
• the use of environmentally harmful non-ferrous metals can be dispensed with.
• control plate and / or the cylinder drum essentially consist of metal in the region of its sliding sides and the layer is applied directly on the metal surface of the sliding sides.
• the layer adheres more consistently to the respective sliding side.
• the functional layer can be applied either directly or preferably by mediation of an adhesive layer.
• the layer is a diamond-like amorphous carbon layer, in particular a tetrahedral hydrogen-free amorphous carbon layer, ta-C.
• the ta-C layer has excellent advantageous properties over conventional carbon layers used in an axial piston machine.
• the fatigue resistance of the friction and wear-reducing layer is significantly increased in particular against adhesive flaking and cohesive removal, in particular with regard to the burden of cavitation and impact forces, which occur especially at elevated working pressure and fast, heavy load changes.
• the wear resistance, especially at elevated load and dirty fluids is improved.
• FIG. 1 is a schematic representation of an axial piston according to the invention
• FIG. 2 shows the detail II shown in Fig. 1 in an enlarged form
• Fig. 3 shows a preferred embodiment of a control plate of the invention
• Axial piston machine in a plan view of the sliding side of the control plate
• Fig. 4 shows a preferred embodiment of a cylinder drum of the invention
• the axial piston machine shown in Fig. 1 is in swash plate design with adjustable
• Displacement volume and a flow direction includes in a known manner as essential components a hollow cylindrical housing 1 with a frontally open
• Control mirror is called a drive shaft 5 and a
• the swash plate 3 is formed as a so-called pivoting cradle with a semi-cylindrical cross-section and is supported by two bearing surfaces extending at a mutual distance parallel to the pivoting direction hydrostatic relief on two correspondingly shaped bearing shells 8, which are fixed to the inner surface of the connecting plate 2 opposite housing end wall 9.
• the hydrostatic discharge takes place in a known manner via pressure pockets 10 which are formed in the bearing shells 8 and are supplied via connections 11 with pressure medium.
• An accommodated in a bulge of a cylindrical housing wall 12 adjusting device 13 engages over an extending in the direction of the terminal plate 2 arm 14 on the swash plate 3 and serves to pivot the same about a pivot axis perpendicular to the pivot axis.
• the remaining bore portion is formed with a conical shape. It tapers from its cross section of greatest diameter near the first bore section to its cross section of smallest diameter near the abutting on the control plate 4 end or bearing surface of the cylinder drum 6.
• the defined by the drive shaft 5 and this conical bore portion annular space is denoted by the reference numeral 25 denotes.
• Each slide shoe 31 is provided on its sliding surface 32 facing the sliding surface, each with a pressure pocket, not shown, which via a through hole 33 in the shoe 31 to a stepped axial Through passage 34 is connected in the piston 29 and connected in this way with the delimited by the piston 29 in the cylinder bore 26 working space of the cylinder.
• a throttle is formed in the region of the associated ball head 30.
• An axially displaceable means of the spline connection 24 arranged on the drive shaft 5 and acted upon by a spring 35 in the direction of the swash plate 3 hold-down device 36 holds the sliding blocks 31 in abutment against the sliding disk 32nd
• the axial piston machine 1 is provided for operation with oil as the pumped medium.
• the cylinder drum 6 is rotated together with the piston 29 in rotation.
• the swashplate 3 is pivoted into an inclined position relative to the cylinder drum 6 by actuation of the adjusting device 13, all pistons 29 perform lifting movements.
• each piston 29 passes through a suction and a compression stroke, with corresponding oil flows are generated, the supply and discharge via the MündungskanäIe 27, the control slots 15 and the pressure and suction channel 16D, 16S done.
• Fig. 2 shows the detail II shown in Fig. 1 in an enlarged form, whereby the area around the layer 46, the control plate 4 and the cylinder barrel 6, as well as around the first sliding side 44, the second sliding side 45 and the opening 15 thereby enlarged is.
• the layer 46 is arranged on the first sliding side 44, that is to say on the control plate 4.
• the layer 46 preferably consists of a tetrahedral hydrogen-free amorphous diamond-like carbon, which is known by the abbreviation ta-C from the group of DLC layers (Diamond Like Carbon layers).
• the layer 46 opposite the second sliding side 45 of the likewise completely made of steel cylinder drum 6 is preferably hardened by nitriding.
• the rotational movement between the layer 46 and the second sliding side 45 forms a hydrodynamic sliding film, which is formed by the conveying medium.
• the layer rubs 46 on the second sliding layer 45. Due to the hydraulic pressure fluctuations occurring in the axial piston 1, especially when the axial piston is very stressed, the second sliding side 45 abruptly fall back on the layer 46 again. This creates a beating load which depends in particular on the working pressures and the pressure fluctuation curve in terms of their strength.
• not shown notches may be arranged on the opposite direction of rotation end or holes in the control plate 4 introduced, according to the invention thereby also the surface of these not shown notches and the inner surfaces of the holes, not shown would be coated with the layer 46.
• Material loads due to cavitation preferably occur in axial piston machines in a region 48, which is exemplified by a circular ring.
• the invention is not limited to the embodiments and embodiments.
• the features of the embodiment and the embodiments may be combined with each other in any manner.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Reciprocating Pumps (AREA)
• Pistons, Piston Rings, And Cylinders (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34972701

Family Applications (1)

Country Status (5)

Families Citing this family (11)

Citations (4)

Family Cites Families (17)

• 2004
  • 2004-07-09 DE DE102004033321A patent/DE102004033321B4/de not_active Expired - Fee Related
• 2005
  • 2005-06-08 WO PCT/EP2005/006156 patent/WO2006005399A1/de active Application Filing
  • 2005-06-08 EP EP05761738A patent/EP1769157A1/de not_active Withdrawn
  • 2005-06-08 CN CNA2005800226219A patent/CN101002019A/zh active Pending
  • 2005-06-08 US US11/632,094 patent/US20100000401A1/en not_active Abandoned

Patent Citations (4)

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