Swashplate type axial-piston pump
OwnerIngo Valentininventor
Life of this patent
Estimating the term…
Abstract
An axial-piston pump includes a rotatable cylinder barrel having pistons extending from cylinder bores formed at one end thereof. A swashplate is positioned adjacent the cylinder barrel and includes an inclined surface for engaging and reciprocating the pistons upon rotation of the cylinder barrel relative thereto. The cylinder barrel is rotatably supported by a bearing spaced from the swashplate in a direction toward the cylinder barrel. The location and orientation of the bearing results in the development of bearing forces which operate on the same equivalent force point as the contact forces developed between the pistons and swashplate. Since the forces thus developed all operate on the same equivalent force point, pitching or cocking moments on the cylinder barrel are substantially eliminated.
Claims20
An axial-piston pump comprising:
- a cylinder barrel assembly having a cylinder barrel and a piston received in a cylinder bore in said cylinder barrel;
- a swashplate having an inclined surface engaging said cylinder barrel assembly for exerting an equivalent force on an equivalent force point located between said inclined surface and said cylinder barrel in response to rotation if said cylinder barrel assembly relative to said swashplate, said equivalent force including an axial component for reciprocating said piston in said cylinder bore and a radial component oriented substantially perpendicularly to said axial component, and
- means spaced from said equivalent force point in a direction toward said cylinder barrel for supporting said cylinder barrel assembly for rotation relative to said swashplate and for developing on said equivalent force point a bearing force having a radial bearing force component substantially equal in magnitude and opposite in direction to said radial equivalent force component such that the net resultant sum of said radial equivalent and radial bearing force components is substantially zero.
An axial-piston hydraulic pump comprising:
- a cylinder barrel assembly including a cylinder barrel defining a central rotational axis and a plurality of pistons received in respective cylinder bores formed in said cylinder barrel around said rotational axis in parallel alignment therewith;
- a swashplate mounted adjacent one end of said cylinder barrel assembly having a surface engaging said cylinder barrel assembly and intersecting said rotational axis at a non-perpendicular angle relative thereto for reciprocating said piston within said cylinder bores upon rotation of said cylinder barrel assembly relative to said swashplate, said cylinder barrel assembly and said surface developing an equivalent contact force therebetween having axial and radial components operating on a single equivalent force point on said rotational axis, said equivalent force point being spaced from said cylinder barrel in a direction toward said swashplate;
- and
- means engaging said cylinder barrel for supporting said cylinder barrel assembly for rotation relative to said swashplate, said means including a bearing defining a plane perpendicular to said rotational axis and intersecting said rotational axis at a point spaced from said equivalent force point in a direction toward said cylinder barrel and having a barrel race oriented such that the total bearing force developed by said bearing intersects said rotational axis substantially at said equivalent force point, whereby the total moment on said cylinder barrel resulting from the radial component of said total bearing force and said radial component of said equivalent contact force is substantially zero.
Dependencies are inferred from the claim text.