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`What Is Claimed Is:
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`1.
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`A hydraulic transaxle, comprising:
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`an axial piston hydraulic pump having a variable displacement,
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`wherein the hydraulic pump includes a movable swash plate and a pair of trunnion
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`shafts coaxial to each other, the pair of trunnion shafts being joined to the swash plate
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`separably from the swash plate,
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`wherein the swash plate is rotatable centered on a common axis of the trunnion
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`shafts to control the displacement of the hydraulic pump, the common axis of the trunnion
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`shafts defining an axial direction of the trunnion shafts perpendicular to a rotary axis of
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`the hydraulic pump; and
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`a transaxle casing incorporating the hydraulic pump,
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`wherein the transaxle casing includes a pair of side walls opposite each other in
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`the axial direction of the trunnion shafts with respect to the hydraulic pump,
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`wherein the transaxle casing includes a pair of casing holes each of which
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`penetrates each of the side walls between an inside of the transaxle casing and an outside
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`of the transaxle casing,
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`wherein the pair of trunnion shafts are passed through the respective casing holes
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`to be pivotally supported by the respective side walls of the transaxle casing,
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`wherein the swash plate is formed with a pair of side portions opposite each other
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`in the axial direction of the trunnion shafts, the pair of side portions facing the respective
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`side walls in the inside of the transaxle casing,
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`wherein the swash plate is formed with a pair of swash plate holes in the
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`respective side portions, the pair of swash plate holes being open to the pair of casing
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`holes, respectively
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`wherein proximal end portions of the respective trunnion shafts are inserted into
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`the respective swash plate holes to be engaged to the swash plate unrotatably, relative to
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`the swash plate, and
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`wherein a distal end portion of one of the trunnion shafts projects from the
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`corresponding casing hole to the outside of the transaxle casing so as to be operatively
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`connected to an operation device for controlling the displacement of the hydraulic pump.
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`2.
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`The hydraulic transaxle according to claim 1,
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`wherein the pair of side portions of the swash plate are formed with respective
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`distal end surfaces that are adjacent to inside surfaces of the respective side walls of the
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`transaxle casing so that a width of the swash plate between the distal end surfaces in the
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`axial direction of the trunnion shafts is equal to or slightly less than a distance between
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`the inside surfaces of the side walls of the transaxle casing in the axial direction of the
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`trunnion shafts.
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`3.
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`The hydraulic transaxle according to claim 1,
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`wherein the transaxle casing includes at least two housing members joined to each
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`other at a joint plane parallel to the common axis of the trunnion shafts, and
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`wherein one of the at least two housing members is formed integrally with the pair
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`of side walls having the respective casing holes.
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`4.
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`The hydraulic transaxle according to claim 1, further comprising:
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`a control arm provided on an outside end portion of a corresponding one of the
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`side walls of the transaxle casing to be fixed on the distal end portion of the one of the
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`trunnion shafts so as to operatively connect the swash plate to the operation device; and
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`a neutral biasing mechanism for biasing the swash plate to a neutral position for
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`the hydraulic pump,
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`wherein the trunnion shafts are identical in shape to each other, and
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`wherein the neutral biasing mechanism is provided on an outside end portion of
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`the other of the side walls of the transaxle casing to be provided on a distal end portion of
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`the other of the trunnion shafts.
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