Bent axis variable delivery inline drive axial piston pump and/or motor

Abstract

A bent axis, variable displacement inline drive device may comprise: a port plate having fluid passages; a cylinder block rotatably mounted adjacent the port plate and having axial cylinders having openings in alternating fluid communication with the fluid passages; a rotatable shaft coupled through the port plate to the cylinder block, pistons in the cylinders and having a connecting rod extending from the cylinder block; a rotatable spindle having receptacles for receiving the connecting rods; a pivotable yoke having the spindle rotatably mounted thereon, whereby the rotating group comprising the spindle, pistons and cylinder block are connected by the connecting rods for rotating together, the yoke being pivotable for angling the spindle relative to the cylinder block. The device may be employed as a pump, or as a motor, or as both a pump and a motor, and the yoke may be pivoted over center.

What is claimed is: 
     
         1 . A bent axis, variable displacement inline drive device comprising:
 a port plate having a seat for receiving a rotatable cylinder block therein, and having at least two fluid passages each coupled to a respective fluid port and each having an arcuate opening corresponding to a different less than 180° portion of a circle;   a cylinder block rotatably mounted adjacent the seat of said port plate for rotation about an axis, said cylinder block having a circular array of axial cylinders therein each having an opening at a seat end thereof adjacent the seat of said port plate and located to be in alternating fluid communication with the respective openings of the two fluid passages at different rotational positions in the rotation of said cylinder block;   a rotatable shaft coupled through an opening in said port plate to said cylinder block for rotating therewith;   a plurality of pistons disposed in the cylinders of said cylinder block for reciprocating motion therein, each said piston having a connecting rod extending from an end of said cylinder block opposite the port plate;   a rotatable spindle having a circular array of receptacles therein for receiving the respective ends of said connecting rods;   a pivotable yoke having said spindle rotatably mounted thereon for rotation about an axis, wherein said spindle and plurality of pistons disposed in said cylinder block are connected by said connecting rods for rotating together, said yoke being pivotable for angling the rotational axis of said spindle relative to the rotational axis of said cylinder block, whereby said pivotable yoke is pivotable over center.   
     
     
         2 . The device of  claim 1  wherein:
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder, whereby operating pressure urges said cylinder block toward said port plate; or 
 a spring urges said cylinder block toward said port plate; or 
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder and a spring urges said cylinder block toward said port plate. 
 
     
     
         3 . The device of  claim 1  further comprising a hold down plate attached to said rotatable spindle and rotatable therewith, wherein said hold down plate retains the ends of said connecting rods in the respective receptacles of said rotatable spindle. 
     
     
         4 . The device of  claim 1  wherein each said connecting rod includes:
 a spherical ball at least at one end thereof disposed in a socket of said piston; or 
 a spherical ball at least at the other end thereof disposed in the receptacle of said rotatable spindle; or 
 a spherical ball at one end thereof disposed in a socket of said piston and a spherical ball at the other end thereof disposed in the receptacle of said rotatable spindle. 
 
     
     
         5 . The device of  claim 1  further comprising a universal link connected at one end to at least one of said shaft and said cylinder block and at an other end to said rotatable spindle. 
     
     
         6 . The device of  claim 5  wherein said universal link includes:
 a split spherical ball at least at the one end thereof disposed in a socket at the one of said shaft and said cylinder block; or 
 a split spherical ball at least at the other end thereof disposed in a socket at said rotatable spindle; or 
 a split spherical ball at each end thereof disposed in respective sockets at the one of said shaft and said cylinder block and at said rotatable spindle. 
 
     
     
         7 . The device of  claim 1  wherein said rotatable spindle includes:
 a movable socket for receiving an end of a universal link, wherein said movable socket is movable axially relative to said rotatable spindle; and 
 a spring biasing said movable socket towards said universal link, 
 whereby the movable socket moves with an effective geometric length of said universal link that changes as said pivotable yoke is pivoted. 
 
     
     
         8 . The device of  claim 1  wherein said yoke includes a base for rotatably supporting said rotatable spindle and a pair of bearing plates extending from said base, wherein said yoke is pivotably supported by a pair of bearings connected to the bearing plates of said yoke. 
     
     
         9 . The device of  claim 8  wherein said yoke is pivotable by torque applied at the bearing plate thereof. 
     
     
         10 . The device of  claim 1  wherein said spindle is rotatably supported on said yoke by an axial bearing; or by a radial bearing; or by an axial bearing and a radial bearing. 
     
     
         11 . The device of  claim 1  further comprising: a shaft housing fixedly supporting said port plate and rotatably supporting said shaft and said cylinder block. 
     
     
         12 . The device of  claim 11  wherein said shaft housing further comprises:
 a shaft bearing for rotatably supporting said shaft; or 
 a shaft seal surrounding said shaft; or 
 a bearing for rotatably supporting said cylinder block; or 
 a shaft bearing for rotatably supporting said shaft and a shaft seal surrounding said shaft; or 
 a shaft bearing for rotatably supporting said shaft and a bearing for rotatably supporting said cylinder block; or 
 a bearing for rotatably supporting said cylinder block, a shaft bearing for supporting said shaft and a shaft seal surrounding said shaft. 
 
     
     
         13 . The device of  claim 11  further comprising: a yoke housing mounted to said shaft housing for enclosing said yoke, said spindle and said connecting rods. 
     
     
         14 . The device of  claim 1  wherein:
 a power source rotates said shaft to rotate said cylinder block and said spindle thereby to operate said device as a pump pumping fluid through said port plate; or 
 fluid flows under pressure to said port plate to rotate said spindle and said cylinder block to operate said device as a motor producing torque and/or rotation at said shaft; or 
 a power source rotates said shaft to rotate said cylinder block and said spindle thereby to operate said device as a pump pumping fluid through said port plate and wherein fluid flows under pressure to said port plate to rotate said spindle and said cylinder block to operate said device as a motor producing torque and/or rotation at said shaft. 
 
     
     
         15 . The device of  claim 1  wherein said yoke is pivotable over center relative to the rotational axis of said cylinder block for reversing the direction of fluid flow between the respective fluid ports when said device is utilized as a pump and for reversing the direction of rotation of said shaft when said device is utilized as a motor. 
     
     
         16 . A bent axis, variable displacement inline drive pump device comprising:
 a port plate having a seat for receiving a rotatable cylinder block therein, and having at least two fluid passages each coupled to a respective fluid port and each having an arcuate opening corresponding to a different less than 180° portion of a circle;   a cylinder block rotatably mounted adjacent the seat of said port plate for rotation about an axis, said cylinder block having a circular array of axial cylinders therein each having an opening at a seat end thereof adjacent the seat of said port plate and located to be in alternating fluid communication with the respective openings of the two fluid passages at different rotational positions in the rotation of said cylinder block;   a rotatable shaft coupled through an opening in said port plate to said cylinder block for rotating therewith;   a plurality of pistons disposed in the cylinders of said cylinder block for reciprocating motion therein, each said piston having a connecting rod extending from an end of said cylinder block opposite the port plate;   a rotatable spindle having a circular array of receptacles therein for receiving the respective ends of said connecting rods;   a pivotable yoke having said spindle rotatably mounted thereon for rotation about an axis, wherein said spindle and plurality of pistons disposed in said cylinder block are connected by said connecting rods for rotating together, said yoke being pivotable for angling the rotational axis of said spindle relative to the rotational axis of said cylinder block, whereby said pivotable yoke is pivotable over center.   
     
     
         17 . The device of  claim 16  wherein:
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder, whereby operating pressure urges said cylinder block toward said port plate; or 
 a spring urges said cylinder block toward said port plate; or 
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder and a spring urges said cylinder block toward said port plate. 
 
     
     
         18 . The device of  claim 16  further comprising a hold down plate attached to said rotatable spindle and rotatable therewith, wherein said hold down plate retains the ends of said connecting rods in the respective receptacles of said rotatable spindle. 
     
     
         19 . The device of  claim 16  wherein each said connecting rod includes:
 a spherical ball at least at one end thereof disposed in a socket of said piston; or 
 a spherical ball at least at the other end thereof disposed in the receptacle of said rotatable spindle; or 
 a spherical ball at one end thereof disposed in a socket of said piston and a spherical ball at the other end thereof disposed in the receptacle of said rotatable spindle. 
 
     
     
         20 . The device of  claim 16  further comprising a universal link connected at one end to at least one of said shaft and said cylinder block and at an other end to said rotatable spindle. 
     
     
         21 . The device of  claim 20  wherein said universal link includes:
 a split spherical ball at least at the one end thereof disposed in a socket at the one of said shaft and said cylinder block; or 
 a split spherical ball at least at the other end thereof disposed in a socket at said rotatable spindle; or 
 a split spherical ball at each end thereof disposed in respective sockets at the one of said shaft and said cylinder block and at said rotatable spindle. 
 
     
     
         22 . The device of  claim 16  wherein said rotatable spindle includes:
 a movable socket for receiving an end of a universal link, wherein said movable socket is movable axially relative to said rotatable spindle; and 
 a spring biasing said movable socket towards said universal link, 
 whereby the movable socket moves with an effective geometric length of said universal link that changes as said pivotable yoke is pivoted. 
 
     
     
         23 . The device of  claim 16  wherein said yoke includes a base for rotatably supporting said rotatable spindle and a pair of bearing plates extending from said base, wherein said yoke is pivotably supported by a pair of bearings connected to the bearing plates of said yoke. 
     
     
         24 . The device of  claim 23  wherein said yoke is pivotable by torque applied at the bearing plate thereof. 
     
     
         25 . The device of  claim 16  wherein said spindle is rotatably supported on said yoke by an axial bearing; or by a radial bearing; or by an axial bearing and a radial bearing. 
     
     
         26 . The device of  claim 16  further comprising: a shaft housing fixedly supporting said port plate and rotatably supporting said shaft and said cylinder block. 
     
     
         27 . The device of  claim 26  wherein said shaft housing further comprises:
 a shaft bearing for rotatably supporting said shaft; or 
 a shaft seal surrounding said shaft; or 
 a bearing for rotatably supporting said cylinder block; or 
 a shaft bearing for rotatably supporting said shaft and a shaft seal surrounding said shaft; or 
 a shaft bearing for rotatably supporting said shaft and a bearing for rotatably supporting said cylinder block; or 
 a bearing for rotatably supporting said cylinder block, a shaft bearing for supporting said shaft and a shaft seal surrounding said shaft. 
 
     
     
         28 . The device of  claim 26  further comprising: a yoke housing mounted to said shaft housing for enclosing said yoke, said spindle and said connecting rods. 
     
     
         29 . The device of  claim 16  wherein: a power source rotates said shaft to rotate said cylinder block and said spindle thereby to operate said pump device for pumping fluid through said port plate. 
     
     
         30 . The device of  claim 16  wherein said yoke is pivotable over center relative to the rotational axis of said cylinder block for reversing the direction of fluid flow between the respective fluid ports of said pump device. 
     
     
         31 . A bent axis, variable displacement inline drive motor device comprising:
 a port plate having a seat for receiving a rotatable cylinder block therein, and having at least two fluid passages each coupled to a respective fluid port and each having an arcuate opening corresponding to a different less than 180° portion of a circle;   a cylinder block rotatably mounted adjacent the seat of said port plate for rotation about an axis, said cylinder block having a circular array of axial cylinders therein each having an opening at a seat end thereof adjacent the seat of said port plate and located to be in alternating fluid communication with the respective openings of the two fluid passages at different rotational positions in the rotation of said cylinder block;   a rotatable shaft coupled through an opening in said port plate to said cylinder block for rotating therewith;   a plurality of pistons disposed in the cylinders of said cylinder block for reciprocating motion therein, each said piston having a connecting rod extending from an end of said cylinder block opposite the port plate;   a rotatable spindle having a circular array of receptacles therein for receiving the respective ends of said connecting rods;   a pivotable yoke having said spindle rotatably mounted thereon for rotation about an axis, wherein said spindle and plurality of pistons disposed in said cylinder block are connected by said connecting rods for rotating together, said yoke being pivotable for angling the rotational axis of said spindle relative to the rotational axis of said cylinder block, whereby said pivotable yoke is pivotable over center.   
     
     
         32 . The device of  claim 31  wherein:
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder, whereby operating pressure urges said cylinder block toward said port plate; or 
 a spring urges said cylinder block toward said port plate; or 
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder and a spring urges said cylinder block toward said port plate. 
 
     
     
         33 . The device of  claim 31  further comprising a hold down plate attached to said rotatable spindle and rotatable therewith, wherein said hold down plate retains the ends of said connecting rods in the respective receptacles of said rotatable spindle. 
     
     
         34 . The device of  claim 31  wherein each said connecting rod includes:
 a spherical ball at least at one end thereof disposed in a socket of said piston; or 
 a spherical ball at least at the other end thereof disposed in the receptacle of said rotatable spindle; or 
 a spherical ball at one end thereof disposed in a socket of said piston and a spherical ball at the other end thereof disposed in the receptacle of said rotatable spindle. 
 
     
     
         35 . The device of  claim 31  further comprising a universal link connected at one end to at least one of said shaft and said cylinder block and at an other end to said rotatable spindle. 
     
     
         36 . The device of  claim 35  wherein said universal link includes:
 a split spherical ball at least at the one end thereof disposed in a socket at the one of said shaft and said cylinder block; or 
 a split spherical ball at least at the other end thereof disposed in a socket at said rotatable spindle; or 
 a split spherical ball at each end thereof disposed in respective sockets at the one of said shaft and said cylinder block and at said rotatable spindle. 
 
     
     
         37 . The device of  claim 31  wherein said rotatable spindle includes:
 a movable socket for receiving an end of a universal link, wherein said movable socket is movable axially relative to said rotatable spindle; and 
 a spring biasing said movable socket towards said universal link, 
 whereby the movable socket moves with an effective geometric length of said universal link that changes as said pivotable yoke is pivoted. 
 
     
     
         38 . The device of  claim 31  wherein said yoke includes a base for rotatably supporting said rotatable spindle and a pair of bearing plates extending from said base, wherein said yoke is pivotably supported by a pair of bearings connected to the bearing plates of said yoke. 
     
     
         39 . The device of  claim 38  wherein said yoke is pivotable by torque applied at the bearing plate thereof. 
     
     
         40 . The device of  claim 31  wherein said spindle is rotatably supported on said yoke by an axial bearing; or by a radial bearing; or by an axial bearing and a radial bearing. 
     
     
         41 . The device of  claim 31  further comprising: a shaft housing fixedly supporting said port plate and rotatably supporting said shaft and said cylinder block. 
     
     
         42 . The device of  claim 41  wherein said shaft housing further comprises:
 a shaft bearing for rotatably supporting said shaft; or 
 a shaft seal surrounding said shaft; or 
 a bearing for rotatably supporting said cylinder block; or 
 a shaft bearing for rotatably supporting said shaft and a shaft seal surrounding said shaft; or 
 a shaft bearing for rotatably supporting said shaft and a bearing for rotatably supporting said cylinder block; or 
 a bearing for rotatably supporting said cylinder block, a shaft bearing for supporting said shaft and a shaft seal surrounding said shaft. 
 
     
     
         43 . The device of  claim 41  further comprising: a yoke housing mounted to said shaft housing for enclosing said yoke, said spindle and said connecting rods. 
     
     
         44 . The device of  claim 31  wherein: fluid flows under pressure to said port plate to rotate said spindle and said cylinder block to operate said device as a motor producing torque and/or rotation at said shaft. 
     
     
         45 . The device of  claim 31  wherein said yoke is pivotable over center relative to the rotational axis of said cylinder block for reversing the direction of rotation of the shaft of said motor device. 
     
     
         46 . A bent axis, variable displacement inline drive device rotating group comprising:
 a cylinder block rotatably mountable for rotation about an axis, said cylinder block having a circular array of axial cylinders therein each having an opening at a seat end of said cylinder block located to be in alternating fluid communication with respective openings of plural fluid passages of a port plate at different rotational positions in the rotation of said cylinder block when a port plate is adjacent said cylinder block;   said cylinder block having a central opening at the seat end thereof for receiving a rotatable shaft, whereby a rotatable shaft may be coupled to said cylinder block through an opening in a port plate for rotating therewith;   a plurality of pistons disposed in the cylinders of said cylinder block for reciprocating motion therein, each said piston having a connecting rod extending from an end of said cylinder block opposite the seat end thereof;   a rotatable spindle having a circular array of receptacles therein for receiving the respective ends of said connecting rods;   a pivotable yoke having said spindle rotatably mounted thereon for rotation about an axis, wherein said spindle and said plurality of pistons disposed in said cylinder block are connected by said connecting rods for rotating together, said yoke being pivotable for angling the rotational axis of said spindle relative to the rotational axis of said cylinder block, whereby said pivotable yoke is pivotable over center.   
     
     
         47 . The device rotating group of  claim 46  wherein:
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder, whereby operating pressure urges said cylinder block toward said port plate; or 
 a spring urges said cylinder block toward said port plate; or 
 the opening at the seat end of each axial cylinder has a smaller diameter than does said axial cylinder and a spring urges said cylinder block toward said port plate. 
 
     
     
         48 . The device rotating group of  claim 46  further comprising a hold down plate attached to said rotatable spindle and rotatable therewith, wherein said hold down plate retains the ends of said connecting rods in the respective receptacles of said rotatable spindle. 
     
     
         49 . The device rotating group of  claim 46  wherein each said connecting rod includes:
 a spherical ball at least at one end thereof disposed in a socket of said piston; or 
 a spherical ball at least at the other end thereof disposed in the receptacle of said rotatable spindle; or 
 a spherical ball at one end thereof disposed in a socket of said piston and a spherical ball at the other end thereof disposed in the receptacle of said rotatable spindle. 
 
     
     
         50 . The device rotating group of  claim 46  further comprising a universal link connected at one end to at least one of said shaft and said cylinder block and at an other end to said rotatable spindle. 
     
     
         51 . The device rotating group of  claim 50  wherein said universal link includes:
 a split spherical ball at least at the one end thereof disposed in a socket at the one of said shaft and said cylinder block; or 
 a split spherical ball at least at the other end thereof disposed in a socket at said rotatable spindle; or 
 a split spherical ball at each end thereof disposed in respective sockets at the one of said shaft and said cylinder block and at said rotatable spindle. 
 
     
     
         52 . The device rotating group of  claim 46  wherein said rotatable spindle includes:
 a movable socket for receiving an end of a universal link, wherein said movable socket is movable axially relative to said rotatable spindle; and 
 a spring biasing said movable socket towards said universal link, 
 whereby the movable socket moves with an effective geometric length of said universal link that changes as said pivotable yoke is pivoted. 
 
     
     
         53 . The device rotating group of  claim 46  wherein said yoke includes a base for rotatably supporting said rotatable spindle and a pair of bearing plates extending from said base, wherein said yoke is pivotably supported by a pair of bearings connected to the bearing plates of said yoke. 
     
     
         54 . The device rotating group of  claim 53  wherein said yoke is pivotable by torque applied at the bearing plate thereof. 
     
     
         55 . The device rotating group of  claim 46  wherein said spindle is rotatably supported on said yoke by an axial bearing; or by a radial bearing; or by an axial bearing and a radial bearing. 
     
     
         56 . The device rotating group of  claim 46  further comprising: a housing rotatably supporting said cylinder block and a bearing in said housing for rotatably supporting said cylinder block. 
     
     
         57 . The device rotating group of  claim 46  wherein said yoke is pivotable over center relative to the rotational axis of said cylinder block for reversing the direction of fluid flow between the respective fluid passages of a port plate when said device rotating group is utilized in a pump and for reversing the direction of rotation of said cylinder block when said device rotating group is utilized in a motor.