Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
  • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
  • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
  • F01B3/0035—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
  • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
  • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
  • F01B3/0035—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons
  • F01B3/0038—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons inclined to main shaft axis
• • 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
  • F04B1/2035—Cylinder barrels
• • 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
  • F04B1/22—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 having two or more sets of cylinders or pistons
• • 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
  • F04B1/22—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 having two or more sets of cylinders or pistons
  • F04B1/24—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 having two or more sets of cylinders or pistons inclined to the main shaft axis

Definitions

• the invention relates to an axial piston machine according to the preamble of patent claim 1.
• Such an axial piston machine known for example from US Pat. No. 2,968,286, has a plurality of pistons which are arranged approximately in the axial direction and are guided in a cylinder drum. The end of the cylinder drum is supported on a swash plate, the angle of inclination of which determines the stroke of the pistons.
• a swash plate the angle of inclination of which determines the stroke of the pistons.
• two oppositely oriented rows of pistons are provided in a solution disclosed in US Pat. No. 2,968,286, so that the axial piston machine is correspondingly designed with two cylinder drums and two swash plates.
• the pistons are connected to a shaft which, depending on the design of the axial piston machine, acts as an input or output shaft.
• WO 81/03677 AI discloses a similar solution with oppositely directed rows of pistons, in which the pistons are connected in pairs by means of a connecting rod.
• This connecting rod is supported by a ball joint and with play in the drive flange also allows the compensation of the transverse movements.
• WO 94/10443 AI discloses a generic solution in which the pistons are rigidly connected to the drive flange and extend parallel to the axial direction (shaft). The transversal movements are compensated for by forming the cylinders with curved circumferential surfaces. A similar solution is also disclosed in US 5,636,561.
• US 3,648,567 discloses an axial piston machine with only one row of pistons which is connected to the drive flange in a rotationally fixed manner.
• the pistons projecting parallel to the axial direction are immersed in sleeves of the cylinder drum, which are slidably guided on the swash plate.
• the invention is based on the object of creating an axial piston machine which transversal movements allowed with minimal technical expenditure.
• the axial piston machine has a cylinder drum with a multiplicity of cylinder sleeves, which are supported directly or indirectly on a swash plate, this support takes place according to the invention by means of a joint which is designed in such a way that the transverse movements are compensated for by a tilting movement of the cylinder sleeves. Due to the articulated mounting of the cylinder sleeves with respect to the swashplate, the risk of forming grooves or other running grooves is minimal, so that the running time of the axial piston machine is considerably extended compared to conventional solutions.
• the joint is designed as a universal or ball joint, which enables the cylinder sleeves to be pivoted on all sides in the desired area.
• the ball joint has a joint pin which passes through a bottom of the cylinder sleeve and forms the ball joint with an inner circumferential region of the cylinder sleeve.
• this hinge pin is designed as a spherical cap, on the crowned head of which a seal is formed which bears against the inner circumferential wall of the cylinder sleeve.
• the joint is kinematically reversed by an axially from the bottom of the Cylinder sleeve protruding pin is formed, the free end portion of which is immersed in a receptacle of the swash plate or a component lying against the swash plate, for example a driver, and is sealed there.
• the functional reliability of the axial piston machine according to the invention is improved if the cylinder sleeves are prestressed in the direction of the swash plate.
• this spring pretensioning takes place by means of a spring that engages around the cylinder sleeve and engages on a radially projecting support edge of the cylinder sleeve on the foot side.
• the bottom of the cylinder sleeve is spherical, so that it rolls on this spherical region when tilted.
• the cylinder sleeves are preferably guided on a driver of the cylinder drum, which is supported with an end face on the swash plate and which is non-rotatably connected to the drive or output shaft. It is preferred if the driver has a driver disk with a flange part, on whose ring end face facing away from the swashplate, the cylinder sleeves are supported.
• kidney-shaped openings can be provided in the flange part, into which these hinge pins are inserted.
• the part of the hinge pin that plunges into the kidney-shaped openings can then be positively fixed by means of flange.
• the hinge pins or the pins used in the kinematic reversal are preferably hollow so that pressure medium can be passed through them.
• the axial piston machine can be designed with two oppositely oriented rows of pistons, two cylinder drums and two swash plates.
• the pistons are designed in pairs as double pistons and are connected in a rotationally fixed manner to a drive flange of the shaft.
• the sections of the pistons which are immersed in the cylinder sleeve are conical and widen to form seals.
• the construction according to the invention can be used particularly advantageously in axial piston pumps in which the shaft serves as a drive shaft for driving the pistons and the cylinder drums.
• Figure 1 shows a section through a first embodiment of an axial piston pump according to the invention.
• Fig. 2 is a detailed representation of the embodiment of Fig. 1 and Fig. 3 is a detailed representation of a further embodiment of an axial piston pump.
• FIG. 1 shows a longitudinal section through an axial piston pump 1.
• This has a pump housing 2, on which a tank connection and a pressure connection, not shown, is formed.
• a drive shaft 4 is rotatably mounted via a bearing arrangement 6.
• a free end section of the drive shaft 4 protruding from the pump housing 2 is connected to a drive motor, not shown.
• An inner bore 8 of the pump housing 2 receiving the drive shaft 4 is expanded radially to a pump chamber 10, in which two swash plates 12, 14 are rotatably mounted.
• the two swash plates 12, 14 each have an oblique to the vertical in Fig. 1
• each cylinder drum 18, 20 has a multiplicity of cylinder sleeves 22, 23, in each of which a piston 24, 26 is immersed.
• the swash plates 12, 14 and correspondingly the cylinder drums 18, 20 are arranged symmetrically to the vertical central axis M.
• the two pistons 24, 26 are each formed by the end sections of a double piston 28, which is inserted in a rotationally fixed manner in a radially projecting drive flange 30 of the drive shaft 4.
• the cylinder drums 18, 20 are supported by self-aligning bearings 32, 34 which enable the wobble movement occurring due to the inclined position of the cylinder drums 18, 20 during the rotation of the shaft 4.
• the cylinder drum 20 has a driver 36 which is supported on the drive shaft 4 via the joint 34 and which is supported with a radially widened flange part 40 on the inclined support surface 16 of the swash plate 14.
• the self-aligning bearing 34 engages in an inner bore of a hub-shaped projection 38 of the driver 36.
• the cylinder sleeves 23 of the cylinder drum 20, which are uniformly distributed over the circumference, are supported on an annular end face 42 of the flange part 40 which is distant from the support surface 16. These have a radially protruding, circumferential support edge 44 on the foot side, the bottom surface 46 of which rests on the annular end face 42 is spherical, so that the cylinder sleeve 23 can perform an all-round tilting movement, the spherical bottom surface 46 in each case ensuring a defined contact surface.
• a tension spring 48 engages on the support edge 44, so that the cylinder sleeve 23 is biased into its contact position against the ring end face 42.
• the tension spring 48 is in turn supported on a support ring 58 which engages around the outer circumference of the cylinder sleeves 23 and the hub-shaped projection 38 and is supported in the axial direction by means of a support device 52.
• the cylinder sleeve 23 has a cylinder bore 54 into which the piston forming the end section of the double piston 28 is immersed.
• the radial support of the cylinder sleeve 23 takes place by means of a spherical cap 56 designed as a hinge pin, which dips into the cylinder bore 54 with a spherical head 58 and bears sealingly against the inner circumferential wall of the cylinder bore 54 via a seal 60; the spherical cap 56 is in one of the following Insert 62 of the flange part 40 described in more detail.
• the spherical cap 56 has a bore 64 which opens into an opening 66 in the flange part 40, so that pressure medium can flow from the cylinder space delimited by the cylinder sleeve 23 and the piston 26 to the swash plate 14 and in the opposite direction.
• connection channels are formed, via which, depending on the rotational position (inner, outer dead center) of the cylinder drum 18, a connection is made to the tank or pressure connection in order to lead pressure medium to the cylinder space or pressure medium under high pressure to a consumer to lead.
• the receptacle 62 has a bore section 66, into which the part of the spherical cap 56 which extends away from the head 58 is inserted.
• the bore section 66 opens into a kidney-shaped opening 68, which extends along a radial segment of the pitch circle along which the cylinder sleeves 23 are arranged.
• the axial length of the part of the spherical cap 56 inserted in the bore section 66 is selected such that an end section 70 projects into the opening 68.
• the spherical cap 56 is then attached by flanging these end sections projecting into the kidney-shaped projection 68 (see section X-Y in FIG. 1).
• kidney-shaped openings 68 create space in order to enable a positive connection between the spherical cap 56 and the driver 36.
• the width b of the kidney-shaped opening 68 corresponds to the diameter of the bore section 66.
• the piston 26 is of approximately conical design, its diameter starting from a waist 72 being conically widened to form a piston ring 74 arranged on the foot side and acting as a seal, and then tapering to an end face 76 following the piston ring 74 is.
• the cone angle is chosen so that the circumferential surfaces of the piston 26 do not collide with the inner circumferential surfaces of the cylinder sleeves 22, 23 and straight at the two dead centers (see FIG. 1 above: outer dead center; FIG. 1 below: inner dead center) abut against these, the sealing via the piston ring 74 also having to be ensured in these end positions.
• the geometry of the arrangement according to the invention is selected such that the cylinder sleeves 22, 23 are each aligned vertically at the inner dead center with respect to the end face 16 of the swash plate, so that the tilt angle at the inner dead center, ie. H. minimal when building up pressure and thus a symmetrical support of the cylinder sleeves 22, 23 is ensured.
• FIG. 3 shows a partial view of a further exemplary embodiment of an axial piston pump 1, in which only one cylinder drum 18 is shown.
• the further cylinder drum 20 is designed in a corresponding manner.
• the exemplary embodiment shown in FIG. 3 differs from the previously described exemplary embodiments essentially in the mounting of the cylinder sleeves 22.
• the structure of the double pistons 28, the swash plates 12, 14 and the basic structure of the driver 36 is essentially identical, so that only the different components are discussed below.
• the cylinder sleeve 22 has a flat bottom surface 78, from which a pin 80 projects in the axial direction toward the swash plate 12.
• the pin 80 has at its free end section a head 58 with a seal 60, the structure of which essentially corresponds to that of the exemplary embodiment described above.
• the head 58 is immersed in a bearing receptacle 82 designed as a ball socket and is pretensioned via the tension spring 48 into this engagement position, in which the spherical sections of the head 58 and the bearing receptacle 82 abut one another and thus form a universal joint.
• the end face 78 is arranged at a distance from the adjacent ring end face 42 of the driver 36, so that the sleeve can tilt about the universal joint (82, 58) to compensate for the transverse movement.
• a swash plate 12, 14 is shown with a constant angle of attack.
• this angle of attack can also be designed to vary the stroke.
• the construction described above can also be used with an axial piston motor or also with a hydraulic transformer with an axial design.
• the articulated mounting of the cylinder sleeves 22 is shown Can also be used for variants with only one swash plate and one cylinder drum.
• an axial piston machine with at least one swash plate and a cylinder drum supported thereon, which has a multiplicity of cylinder sleeves.
• a row of pistons is assigned to the cylinder sleeves and is connected to a shaft.
• the cylinder sleeves are articulated in the cylinder drum.

Landscapes

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

Applications Claiming Priority (3)

Publications (2)

Family

ID=32519082

Family Applications (1)

Country Status (5)

Families Citing this family (34)

Family Cites Families (25)

• 2003
  • 2003-12-05 WO PCT/DE2003/004013 patent/WO2004055369A1/fr not_active Ceased
  • 2003-12-05 DE DE50306608T patent/DE50306608D1/de not_active Expired - Lifetime
  • 2003-12-05 AT AT03782132T patent/ATE354729T1/de not_active IP Right Cessation
  • 2003-12-05 US US10/540,113 patent/US7470116B2/en not_active Expired - Fee Related
  • 2003-12-05 DE DE10393875T patent/DE10393875D2/de not_active Expired - Fee Related
  • 2003-12-05 EP EP03782132A patent/EP1573200B1/fr not_active Expired - Lifetime

Non-Patent Citations (1)

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