Rotary actuator such as a hydraulic rotary actuator for a motor vehicle and a method of making a rotary actuator

A rotary actuator comprising:

• housing means;
• means for connecting said housing means to a first portion of a motor vehicle suspension;
• shaft means, said shaft means defining a longitudinal axis;
• at least a portion of said shaft means being rotatably disposed within said housing means;
• means for connecting said shaft means to a second portion of a motor vehicle suspension;
• means for rotatably mounting said at least a portion of said shaft means within said housing means for rotation of at least one of said shaft means and said housing means about said longitudinal axis with respect to the other of said shaft means and said housinq means;
• said shaft means comprising an outer surface disposed towards said housing means;
• said housing means comprising an inner surface disposed towards said outer surface of said shaft means, said inner surface of said housing means being spaced apart from said outer surface of said shaft means to define a chamber between said shaft means and said housing means, said chamber having a first axial end and a second axial end;
• cap means for closing at least one of said first and second axial ends of said chamber;
• means for connecting said cap means to said housing means;
• said means for connecting comprising at least one radial deformation of said housing means;
• said at least one radial deformation of said housing means being configured for engaging at least a portion of said cap means;
• said housing means having a first axial end and a second axial end;
• said cap means fitting within said inner surface of said housing means adjacent at least one of said first and second axial ends of said housing means;
• said radial deformation comprising a radially inward deformation of said housing means for engaging at least a portion of said cap means;
• said cap means comprising:
• a first axial end surface being disposed within said housing;
• a second axial end surface being opposite said first axial end surface;
• and
• a cylindrical outer surface extending axially between said first and second axial end surfaces;
• said radially inward deformation of said housing means engaging at least one of:
• at least a portion of said second axial end surface of said cap means;
• and
• at least a portion of said cylindrical outer surface of said cap means;
• said housing means comprising a cylindrical flange forming said first end of said housing means;
• said radially inward deformation comprising a radially inward deformation of at least a portion of said flange to axially engage said at least a portion of said flange with said at least a portion of said second axial end surface of said cap means;
• said cap means comprising first and second cap means for closing both of said first and second axial ends of said chamber;
• said means for connecting said first cap means to said housing means comprising said radially inward deformation;
• said means for connecting said second cap means to said housing comprising a weld;
• said second cap means comprising said means for connecting said housing means to said first portion of a motor vehicle suspension;
• each of said outer surface of said shaft means, and said inner surface of said housing means, comprising at least two protections extending towards the other of:
• said outer surface of said shaft means, and
• said inner surface of said housing means;
• said projections of said shaft means being disposed between said projections of said housing means;
• each of said projections extending from said first axial end of said chamber to said second axial end of said chamber to axially divide said chamber into at least four chamber portions;
• means for fluidly connecting together at least a first two of said chamber portions;
• means for fluidly connecting together at least a second two of said chamber portions;
• each of said at least a first two chamber portions being disposed between ones of said at least a second two chamber portions;
• each of said at least a second two chamber portions being disposed between ones of said at least a first two chamber portions;
• means for independently introducing fluid into each of:
• said at least a first two chamber portions, and
• said at least a second two chamber portions,
• to relatively rotate said housing means and said shaft means with respect to one another;
• said means for fluidly connecting together said at least a first two of said chamber portions comprising at least a first channel disposed circumferentially about said outer cylindrical surface of said first cap means between said first cap means and said inner surface of said housing means;
• said means for fluidly connecting together said at least a second two of said chamber portions comprising at least a second channel disposed circumferentially about said outer cylindrical surface of said first cap means between said first cap means and said inner surface of said housing means;
• said means for fluidly connecting together said at least a first two of said chamber portions additionally comprising:
• first axial passages in said first cap means in fluid communication with each of said at least a first two of said chamber portions;
• first radial passages in said first cap means extending radially between said first channel and said first axial passages;
• said means for fluidly connecting together said at least a second two of said chamber portions additionally comprising:
• second axial passages in said first cap means in fluid communication with each of said at least a second two of said chamber portions;
• and
• second radial passages in said first cap means extending radially between said second channel and said second axial passages;
• said means for introducing fluid comprising hydraulic connections for fluidly connecting said chamber portions to a fluid supply source;
• said second cap means comprising said hydraulic connections;
• said radially inward deformation comprising a radial inward deformation of all of said flange completely about the circumference of said housing;
• said first and second channels being separated from one another axially on said outer cylindrical surface of said first cap means;
• said cap means further comprising:
• a third channel being disposed between said first channel and said first end surface of said cap means, said third channel being disposed circumferentially about said outer cylindrical, surface of said first cap means, and said third channel comprising a ring-shaped seal disposed therein to seal said outer cylindrical surface of said first cap means to said inner surface of said housing means;
• a fourth channel being disposed between said first channel and said second channel, said fourth channel being disposed circumferentially about said outer cylindrical surface of said first cap means, and said fourth channel comprising a ring-shaped seal disposed therein to seal said outer cylindrical surface of said first cap means to said inner surface of said housing means;
• and
• a fifth channel being disposed between said second channel and said second end surface of said first cap means, said fifth channel being disposed circumferentially about said outer cylindrical surface of said first cap means, and said fifth channel comprising a ring-shaped seal disposed therein to seal said outer cylindrical surface of said first cap means to said inner surface of said housing means;
• each of said projections comprising:
• a first side being disposed towards one of said first two chamber portions;
• a second side being disposed opposite to said first side and adjacent one of said second two chamber portions;
• a surface being disposed between said first side and said second side, said surface being disposed towards the other of:
• said outer surface of said shaft means, and
• said inner surface of said housing means;
• and
• at least one seal means for sealing said surface of said at least one projection to the other of:
• said outer surface of said shaft means, and
• said inner surface of said housing means,
• to minimize fluid flow from said first two chamber portions to said second two chamber portions;
• said first and second cap means comprising gasket means for sealing said cap means about said shaft means;
• said cap means further comprising bearing means for rotatably mounting said shaft means within said cap means;
• said shaft means comprising a longitudinal hole therein disposed along said longitudinal axis of said shaft means;
• at least a portion of said longitudinal hole having a non-round cross section;
• said means for connecting said shaft means to a second portion of a motor vehicle suspension comprising said non-round cross-section of said longitudinal hole;
• said housing comprising a cylinder, said cylinder having an outer surface;
• and
• said weld of said second cap means being disposed circumferentially about said outer surface of said cylinder at said second axial end of said cylinder.