Power take off shifter arrangement
A power take-off assembly includes a first gear, a second gear, a first PTO arrangement having an output gear, a second PTO arrangement having a countershaft gear, a coupler sleeve having internal splines in engagement with a first annular hub of the first gear, and a PTO shifter arrangement having a shifting ring with internal output splines spaced from internal input splines. The internal input splines in sliding engagement with external splines of the coupler sleeve. The shifting ring being translatable between a first position, a second position, and a third position where the internal output splines are engaged with and transfer rotational power to: the output gear only when the shifting ring is in the first position, the output gear and the second gear when the shifting ring is in the second position, and the second gear only when the shifting ring is in the third position.
1 . A power take-off (PTO) assembly for a transmission of a work vehicle, the PTO assembly comprising:
a first gear and a second gear spaced apart about a rotation axis, the first gear having a first annular hub with external splines extending about the rotation axis and the second gear having a second annular hub with external splines extending about the rotation axis;
a first PTO arrangement having an output gear driving an output shaft to rotate about the rotation axis;
a second PTO arrangement having a countershaft gear driven by the second gear to rotate a countershaft arranged in parallel with the output shaft;
a coupler sleeve having internal splines and external splines and disposed about the rotation axis between the first gear and the second gear, the internal splines of the coupler sleeve being in engagement with the external splines of the first annular hub of the first gear; and
a PTO shifter arrangement having a shifting ring disposed about the rotation axis with internal input splines in sliding engagement with the external splines of the coupler sleeve and with internal output splines spaced apart from the internal input splines along the rotation axis by a gap, the shifting ring being translatable along the rotation axis between a first position, a second position, and a third position such that the internal output splines are engaged with and transfer rotational power to: the output gear only when the shifting ring is in the first position, the output gear and the second gear when the shifting ring is in the second position, and the second gear only when the shifting ring is in the third position.
2 . The PTO assembly of claim 1 , wherein the first annular hub extends a distance axially along the rotation axis from the first gear to proximate the output gear and the second annular hub is proximate the output gear opposite the first annular hub.
3 . The PTO assembly of claim 2 , wherein the coupler sleeve extends the distance axially along the rotation axis and is positioned coaxially with the first annular hub along the rotation axis, and wherein the external splines of the coupler sleeve extend the distance axially along the rotation axis.
4 . The PTO assembly of claim 1 , wherein the internal input splines of the shifting ring engage the external splines of the coupler sleeve at a different axial position along the rotation axis for each position of the shifting ring.
5 . The PTO assembly of claim 1 , wherein in the third position the shifting ring is positioned axially along the rotation axis to position the output gear in the gap disengaging the internal output splines from the output gear.
6 . The PTO assembly of claim 1 , wherein the internal input splines comprise first splines and second splines spaced apart axially along the rotation axis from the first splines by a second gap.
7 . The PTO assembly of claim 6 , wherein each external spline of the coupler sleeve includes a locking feature positioned on and extending away from both flanks, wherein in the first position, the locking feature is positioned within the gap, in the second position the locking feature is positioned within the second gap, and in the third position, the locking feature is positioned outside of the shifting ring.
8 . The PTO assembly of claim 7 , wherein the locking features are configured to allow the first splines and second splines to slide axially past the locking features when the shifting ring is not rotating about the rotation axis, and wherein the locking features are configured to prevent the first splines and second splines from sliding axially past the locking features when the shifting ring is rotating about the rotation axis.
9 . The PTO assembly of claim 1 , wherein the first gear, the second gear, and the shifting ring are each positioned coaxially with the first PTO arrangement.
10 . The PTO assembly of claim 1 , wherein a housing of the transmission defines a rear access opening to provide access to the first PTO arrangement, the second PTO arrangement, the first gear, the second gear, the coupler sleeve, and the PTO shifter arrangement.
11 . A transmission of a work vehicle, the transmission comprising:
a housing defining a rear access opening and a rear cover positioned over the rear access opening; and
a PTO assembly positioned within the housing, the PTO assembly comprising:
a first gear and a second gear spaced apart about a rotation axis, the first gear having a first annular hub with external splines extending about the rotation axis and the second gear having a second annular hub with external splines extending about the rotation axis;
a rear PTO arrangement having an output gear driving an output shaft to rotate about the rotation axis, wherein the output shaft extends through the rear cover;
a middle PTO arrangement having a countershaft gear driven by the second gear to rotate a countershaft arranged in parallel with the output shaft, the countershaft extending along the housing away from the rear PTO arrangement;
a coupler sleeve having internal splines and external splines and disposed about the rotation axis between the first gear and the second gear, the internal splines of the coupler sleeve being in engagement with the external splines of the first annular hub of the first gear; and
a PTO shifter arrangement having a shifting ring disposed about the rotation axis with internal input splines in sliding engagement with the external splines of the coupler sleeve and with internal output splines spaced apart from the internal input splines along the rotation axis by a gap, the shifting ring being translatable along the rotation axis between a first position, a second position, and a third position such that the internal output splines are engaged with and transfer rotational power to: the output gear only when the shifting ring is in the first position, the output gear and the second gear when the shifting ring is in the second position, and the second gear only when the shifting ring is in the third position.
12 . The transmission of claim 11 , wherein the first annular hub extends a distance axially along the rotation axis from the first gear to proximate the output gear and the second annular hub is proximate the output gear opposite the first annular hub.
13 . The transmission of claim 12 , wherein the coupler sleeve extends the distance axially along the rotation axis and is positioned coaxially with the first annular hub along the rotation axis, and wherein the external splines of the coupler sleeve extend the distance axially along the rotation axis.
14 . The transmission of claim 11 , wherein the internal input splines of the shifting ring engage the external splines of the coupler sleeve at a different axial position along the rotation axis for each position of the shifting ring.
15 . The transmission of claim 11 , wherein in the third position the shifting ring is positioned axially along the rotation axis to position the output gear in the gap disengaging the internal output splines from the output gear.
16 . The transmission of claim 11 , wherein the internal input splines comprise first splines and second splines spaced apart axially along the rotation axis from the first splines by a second gap.
17 . The transmission of claim 16 , wherein each external spline of the coupler sleeve includes a locking feature positioned on and extending away from both flanks, wherein in the first position, the locking feature is positioned within the gap, in the second position the locking feature is positioned within the second gap, and in the third position, the locking feature is positioned outside of the shifting ring.
18 . The transmission of claim 17 , wherein the locking features are configured to allow the first splines and second splines to slide axially past the locking features when the shifting ring is not rotating about the rotation axis, and wherein the locking features are configured to prevent the first splines and second splines from sliding axially past the locking features when the shifting ring is rotating about the rotation axis.
19 . The transmission of claim 11 , wherein the first gear, the second gear, and the shifting ring are each positioned coaxially with the rear PTO arrangement.
20 . The transmission of claim 11 , wherein the rear access opening is configured to provide access to the rear PTO arrangement, the middle PTO arrangement, the first gear, the second gear, the coupler sleeve, and the PTO shifter arrangement.