Claims:
1. An improved power shuttle transmission for a work vehicle for providing smooth transition during change in direction of motion from forward to reverse or vice versa, comprising of :

a. a transmission housing (100) having a front end and a rear end;
b. driving unit (101) placed at the front end of the transmission housing (100);
c. a first gear (104) placed in contact with the driving unit (101);
d. a main shaft (102) place adjacent to the first gear (104);
e. a secondary shaft (103), placed parallel to the main shaft (102);
f. a second gear (105) mounted on the secondary shaft (103);
g. a clutch housing (106) mounted on the main shaft (102);
h. a third gear (109) positioned on the main shaft (102);
i. a plurality of hydraulic pipelines (110, 111, 112) positioned on the main shaft (102);
j. an external manifold (117) positioned on the external surface of the transmission housing (100), wherein said external manifold is connected with the plurality of the hydraulic pipelines (110, 111, 112);
k. an internal manifold (116) positioned on the main shaft, wherein the said internal manifold is connected with the plurality of the hydraulic pipelines (110, 111, 112), said internal manifold receives hydraulic fluid from the external manifold through the plurality of the hydraulic pipelines (110, 111, 112);
l. a drop gear unit (114) positioned adjacent to the plurality of hydraulic pipelines (110, 111, 112);
m. a speed reducing unit (113) positioned adjacent to the drop gear unit (114);
n. a fourth gear (115) mounted on the secondary shaft (103) positioned adjacent to the drop gear unit (114); and
o. an idler gear shaft (201) having a fifth gear (202) and a sixth gear (203), placed in contact with the fourth gear (115) and the third gear (109) respectively.

2. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said driving unit (101) comprises a fly-wheel (204) and a damper (205), for transferring the energy from the engine to the first gear (104).

3. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said second gear (105) mounted on the secondary shaft (103), is in contact with the first gear (104) mounted on the main shaft (102).

4. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said clutch housing (106) comprises of , a first clutch pack (107) and a second clutch pack (108).

5. An improved power shuttle transmission for the work vehicle as claimed in claim 4, wherein the said first clutch pack (108) is a forward clutch pack.

6. An improved power shuttle transmission for the work vehicle as claimed in claim 4, wherein the said second clutch pack (109) is a reverse clutch pack.

7. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said plurality of hydraulic pipelines includes a first pipeline (110), a second pipeline (111) and a third pipeline (112).

8. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said external manifold (117) supplies hydraulic oil to the internal manifold (116) through plurality of hydraulic pipelines (110, 111, 112).

9. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said plurality of hydraulic pipelines (110, 111, 112) supply hydraulic oil to the internal manifold (116)
10. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said secondary shaft (103) is a power take-off shaft.

11. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein when the work vehicle is operated in neutral condition, the driving unit (101) rotates in counter clock-wise direction, transmits the rotational energy to the first gear (104) which transfers it to the second gear (105), the secondary shaft (103) is driven in the clock-wise direction by the first gear (104) through the second gear (105), the fourth gear (115) drives the fifth gear (202), and the sixth gear (203) drives the third gear (109), there exists no supply of hydraulic fluid to the first clutch pack (107) and the second clutch pack (108) which limits their engagement with the first gear (104) and the third gear (109), the speed reducing unit (113) does not receive rotation energy from the main shaft (102) due to non-engagement of either the first clutch pack (107) with the first gear (104) or the second clutch pack (108) with the third gear (109), thus the work vehicle does not move either in forward direction or in reverse direction.

12. An improved power shuttle transmission for the work vehicle as claimed in claim 1,wherein when the work vehicle is operated in the forward direction of motion, the driving unit (101) rotating in counter clockwise direction, transmits the rotational energy to the first gear (104) which transfers it to the second gear (105), the secondary shaft (103) is driven in the clock-wise direction by the first gear (104) through the second gear (105), the first hydraulic pipeline (110) receives the hydraulic fluid from the external manifold (117) to engage the first clutch pack (107), wherein the said hydraulic fluid is supplied to the first clutch pack(107) from the first pipeline (110) through the internal manifold (116), said hydraulic fluid engages the first clutch pack (107) with the first gear (104), wherein the main shaft (102) receives rotational energy from first gear (104) due to the engagement of the first clutch pack (107) and the first gear (104), the speed reducing unit (113) receives rotational energy from the main shaft (102) through the drop gear unit (114) to operate the work vehicle in forward direction of motion, wherein the fourth gear (115) mounted on the secondary shaft (103) drives the fifth gear (202), the sixth gear (203) drives the third gear (109) while the said third gear (109) is connected with the clutch pack (108), there exists no supply of hydraulic fluid to the clutch pack (108) which prevents them from getting engaged, resulting in no energy transfer through the clutch pack (108).

13. An improved power shuttle transmission for the work vehicle as claimed in claim1 and claim 12, wherein the said direction of rotational energy of the main shaft (102) is counter clockwise direction.

14. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein when the work vehicle is operated in the reverse direction of motion, the driving unit (101) rotating in counter clockwise direction, transmits the rotational energy to the first gear (104) which transfer it to the second gear (105), the secondary shaft (103) is driven in the clock-wise direction by the first gear (104) through the second gear (105), the fourth gear (115) drives the fifth gear (202) and the sixth gear (203) drives the third gear (109), the hydraulic fluid from the second external manifold through the second internal manifold by means of second hydraulic pipes (111), is supplied to the second clutch pack (108) to engage the said second clutch pack (108) with the third gear (109), the main shaft (102) receives rotational energy from the third gear (109) due to engagement of the second clutch pack (108) with the third gear (109), the speed reducing unit (113) receives the rotational energy from the main shaft (102) through the drop gear unit (114) to operate the work vehicle in reverse direction, there exists no supply of hydraulic oil to the clutch pack (107) which prevents them from getting engaged resulting in no energy transfer through clutch pack (107).

15. An improved power shuttle transmission for the work vehicle as claimed in claim 1 and claim 14, wherein the said direction of rotational energy of the main shaft (102) is clockwise direction.

16. An improved power shuttle transmission for the work vehicle as claimed in claim 1, wherein the said third hydraulic pipeline (112) supplies coolant to the said clutch packs (107 & 108) and also provide sufficient cooling of the clutch housing (106).
, Description:AN IMPROVED POWER SHUTTLE TRANSMISSION
FIELD OF THE INVENTION
The present invention relates to a transmission assembly of a work vehicle, in particular it relates to a power shuttle transmission of a work vehicle.
BACKGROUND OF THE INVENTION
The work vehicle like tractor often requires to move forward and reverse direction, therefore frequent pressing and release of the clutch pedal by the driver will be required. To eliminate this problem and to reduce the fatigue occurred due to the frequent pressing and releasing of clutch, power shuttle transmission was introduced. The power shuttle transmission enables the driver to change the direction of motion of the work vehicle from forward to reverse direction and vice versa without pressing and releasing the clutch pedal. Most of the tractors provide a power take-off (PTO) speed of 540 RPM for various tractor applications. Achieving 540 PTO RPM with single idler gear construction on existing gearbox layout is not available. Also, any lesser ratio in PTO drop ratio entails a 2-speed IPTO or multiple speed PTO to suffice the requirement of 540 PTO RPM.
The patent document US-6212966 describes a control system for a power shuttle transmission, comprising a first clutch pack, a second clutch pack and means to engage and disengage the first and/or second clutch pack, the control system comprising a control means to initiate and complete engagement and/or disengagement cycles and an adjustment means for adjusting the said engagement/disengagement cycle. This provides a uncomplicated transmission and controller to be customised by the operator to suit his requirements for a variety of tasks, each having different demands on the power shuttle transmission.
KR 1020140026820 discloses a shuttle transmission for an agricultural vehicle includes a power transfer shaft, a transmission shaft, and a shuttle shaft. A high and low speed shifting clutch and a forward and reverse shuttle clutch operated by hydraulic pressure and connected by power are provided to the transmission shaft and the shuttle shaft, respectively. Power output from an engine is transmitted to the shifting clutch via the power transfer shaft prior to the shuttle clutch. The shuttle clutch and the shuttle shaft on the power transfer shaft can be rotated forward and reverse by rotational force transferred to the shifting clutch.
JP2003191763 provides a power transmission device for a driving vehicle to shift the direction of travel from forward to reverse via a shuttle idler gear of a shuttle mechanism. The shuttle mechanism sets up a power transmission system that transmits power via the shuttle idler gear on a forward travelling side, and a direct drive position on a backward travelling side.
JP2001105905 discloses a power shift transmission comprising of : a main transmission for changing a running speed to a plurality of shift steps; and a shuttle transmission for shifting travelling state to forward travelling state and backward travelling state. The main transmission and shuttle transmission are arranged in a transmission case. Further this reduces the loss in torque associated with operation of a clutch, and efficiently cools the hydraulic clutch.
The above cited prior-art documents describes various power shuttle transmission system for performing variety of operations, but none of the prior-art documents address the inclusion of Power shuttle transmission compactly packed in an existing transmission, with all the intended functions of power shuttle tractor without disturbing the existing standard 540 rpm PTO speed. Therefore there is need in art to address the problems of including power shuttle function in existing transmission without affecting the standard PTO speed. The present invention provides an improved power shuttle transmission for work vehicles to provide a smooth transition of direction of motion of the work vehicle from forward to reverse and vice versa. The present invention also provides a means for maintaining the standard speed of the PTO and thus eliminating the mandatory need of 2 speed Independent PTO (IPTO) or multi-speed IPTO. Further, the present invention maintains the same wheelbase of the work vehicle and hence enable power shuttle transmission swapping with minimal component changes on the existing base with simple construction of transmission components.
OBJECTIVE OF THE INVENTION
The present invention as embodied by the improved power shuttle transmission, succinctly fulfils the above-mentioned need(s) in the art. The present invention has objective(s) arising as a result of the above-mentioned need(s), said objective(s) being enumerated below. In as much as the objective(s) of the present invention are enumerated, it will be obvious to a person skilled in the art that, the enumerated objective(s) are not exhaustive of the present invention in its entirety, and are enclosed solely for the purpose of illustration. Further, the present invention encloses within its scope and purview, any structural alternative(s) and/or any functional equivalent(s) even though, such structural alternative(s) and/or any functional equivalent(s) are not mentioned explicitly herein or elsewhere, in the present disclosure. The present invention therefore encompasses also, any improvisation(s)/modification(s) applied to the structural alternative(s)/functional alternative(s) within its scope and purview. The present invention may be embodied in other specific form(s) without departing from the spirit or essential attributes thereof.
The main objective of the present invention is to provide a smooth transition of direction of motion of the work vehicle from forward to reverse and vice versa.
Another objective of the present invention is to provide a means for maintaining standard speed of the PTO and thus eliminating the mandatory need of 2 speed Independent PTO (IPTO) or multi-speed IPTO when power shuttle transmission/configuration is used.
Still another objective of the invention is to provide a work vehicle with plurality of forward and reverse gears.
Yet another objective of the present invention is to provide a two stage idler gear in the power shuttle transmission for smooth transition of direction of motion of the work vehicle from forward to reverse and vice versa.
Final objective of the present invention is to maintain the same wheelbase of the work vehicle and hence enable power shuttle transmission swapping with minimal component changes on the existing base with simple construction of transmission components.
BRIEF DESCRIPTION OF THE DIAGRAM
Figure 1 represents the improved power shuttle transmission unit of the present invention.
Figure 2 depicts the improved power shuttle transmission unit with two stage idler gear showing the power flow from the engine to the gear box for forward and reverse mode of operation.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
SUMMARY
The present invention provides an improved power shuttle for a work vehicle to provide a smooth transition during change in operating direction from forward to reverse or vice versa, comprising of : a transmission housing (100); a driving unit (101) comprising a fly-wheel (204) and a damper (205); a main shaft (102); a secondary shaft (103); a first gear (104); a second gear (105); a clutch housing (106) having a first clutch pack (107) and a second clutch pack (108); a third gear (109); a plurality of hydraulic pipes (110, 111, 112); a plurality of external manifold; a plurality of internal manifold; a drop gear unit (114); a speed reducing unit (113); a fourth gear (115); and an idler gear shaft (201) having a fifth gear (202) and a sixth gear (203). The present invention employs two stage reduction unit idler gear shaft (201) which eliminates the mandatory need of multi-speed power take off or 2-speed independent power take off to maintain the output of the secondary shaft at 540 RPM. Further, the present invention can be used as such in the vintage and old tractor’s transmission unit to maintain the same wheelbase of the work vehicle which makes the power shuttle transmission swapping with minimal component changes on the existing base with simple construction of transmission components.
DETAILED DESCRIPTION OF THE INVENTION
The present invention as embodied by an improved power shuttle transmission, succinctly fulfils the above-mentioned need(s) in the art. The present invention has objective(s) arising as a result of the above-mentioned need(s), said objective(s) being enumerated below. In as much as the objective(s) of the present invention are enumerated, it will be obvious to a person skilled in the art that, the enumerated objective(s) are not exhaustive of the present invention in its entirety, and are enclosed solely for the purpose of illustration. Further, the present invention encloses within its scope and purview, any structural alternative(s) and/or any functional equivalent(s) even though, such structural alternative(s) and/or any functional equivalent(s) are not mentioned explicitly herein or elsewhere, in the present disclosure. The present invention therefore encompasses also, any improvisation(s)/modification(s) applied to the structural alternative(s)/functional alternative(s) within its scope and purview. The present invention may be embodied in other specific form(s) without departing from the spirit or essential attributes thereof.
Throughout this specification, the use of the word "comprise" and variations such as "comprises" and "comprising" may imply the inclusion of an element or elements not specifically recited.
The present invention provides an improved power shuttle transmission for a work vehicle to provide a smooth transition during change in operating direction from forward to reverse or vice versa, comprises of : a transmission housing (100) having a front end and a rear end; a driving unit (101) comprising a fly-wheel (204) and a damper (205), placed at the front end of the transmission housing (100), for transferring the energy from the engine; a first gear (104) receives the energy from the engine through the driving unit (101); a main shaft (102) placed adjacent to the first gear (104); a secondary shaft (103) placed parallel to the main shaft (102); a second gear (105) mounted on the secondary shaft (103), said second gear (105) is in contact with the first gear (104); a clutch housing (106) having a first clutch pack (107) and a second clutch pack (108) is mounted on the main shaft (102), placed adjacent to the first gear (104); a third gear (109) positioned on the main shaft (102), placed adjacent to the clutch assembly (106); a plurality of hydraulic pipelines including a first hydraulic pipeline (110), a second hydraulic pipeline (111) and a third hydraulic pipeline (112) positioned above the main shaft (102); an external manifold (117) positioned on the top surface of the transmission housing (100), The said plurality of hydraulic pipelines including a first hydraulic pipeline (110), a second hydraulic pipeline (111) and a third hydraulic pipeline (112) are connected to external manifold (117); an internal manifold (116) positioned on the main shaft (102), wherein the said internal manifold (116) receives the hydraulic fluid from the said external manifold (117) through a plurality of hydraulic pipelines (110, 111, 112); a drop gear unit (114) positioned adjacent to the said plurality of hydraulic pipelines (110, 111, 112), mounted on the said main shaft (102) and the said secondary shaft (103); a speed reducing unit (113) positioned adjacent to the drop gear unit (114) at the rear end of the transmission housing (100); a fourth gear (115) mounted on the secondary shaft (103) is positioned adjacent to the drop gear unit (114); and an idler gear shaft (201) having a fifth gear (202) and a sixth gear (203), placed in contact with the fourth gear (115) and the third gear (109) respectively.
In the preferred embodiment, wherein the said secondary shaft (103) is preferably a power take-off shaft.
In the preferred embodiment, wherein the said first clutch pack (107) is a forward clutch pack and the said second clutch pack (108) is a reverse clutch pack.
In the preferred embodiment, wherein the said idler gear shaft (201) is used to cater a two-stage reduction ratio between secondary shaft (103) and main shaft (102).
In an embodiment of the present invention, when the work vehicle is in neutral, the driving unit (101) rotates in counter clock-wise direction, transmits rotational energy to the first gear (104) which transfers it to the second gear (105), the secondary shaft (103) is driven in the clock-wise direction by the first gear (104) through the second gear (105), furthermore, the fourth gear (115) drives the fifth gear (202), and the sixth gear (203) drives the third gear (109), the hydraulic fluid is not supplied to the first clutch pack (107) and the second clutch pack (108), therefore the first clutch pack (107) is not engaged with the first gear (104) and the second clutch pack (108) is not engaged with third gear (109), furthermore, the speed reducing unit (113) does not receive rotation energy from the main shaft (102) due to non-engagement of either the first clutch pack (107) with the first gear (104) or the second clutch pack (108) with the third gear (109), thus the work vehicle does not move either in forward direction or in reverse direction.
In an another embodiment of the present invention, when the work vehicle is operated in the forward direction of motion, the driving unit (101) rotates in counter clock-wise direction, transmits the rotational energy to the first gear (104). The second gear (105) receives the energy from the first gear (104), the secondary shaft (103) is driven in the clock-wise direction by the first gear (104) through the second gear (105). The first hydraulic pipeline (110) receives the hydraulic fluid to engage the first clutch pack (107) from the said external manifold (117), wherein said hydraulic fluid is supplied to the first clutch pack (107) from the first pipeline (110) through the said internal manifold (116), wherein the said hydraulic fluid engages the said first clutch pack (107) with the first gear (104), wherein the said main shaft (102) receives rotational energy from the first gear (104) due to the engagement of the first clutch pack (107) with the first gear (104), the speed reducing unit (113) receives rotational energy in clock-wise direction from the main shaft (102) through the drop gear unit (114) to operate the work vehicle in forward direction of motion. The coolant is supplied to the clutch housing (106), the external manifold (117) through the internal manifold (116) via the third hydraulic pipeline (112) enables the cooling of the said clutch housing (106). The fourth gear (115) mounted on the secondary shaft (103) drives the fifth gear (202), furthermore, the sixth gear (203) drives the third gear (109) while the said third gear (109) is connected with the clutch pack (108). Since there exists no supply of hydraulic fluid to the clutch pack (108), hence engagement does not happen and no energy transfer occurs through clutch pack (108).
In an yet another embodiment, when the work vehicle is operated in the reverse direction of motion, the driving unit (101) rotates in counter clock-wise direction, wherein the driving unit (101) transmits the rotational energy to the first gear (104). The second gear (105) receives the energy from the first gear (104), the secondary shaft (103) is driven in the clock-wise direction by the first gear (104) through the second gear (105). The fourth gear (115) drives the fifth gear (202), furthermore, the sixth gear (203) drives the third gear (109). The hydraulic fluid from the external manifold (117) through the internal manifold (116) by means of second hydraulic pipe (111), is supplied to the second clutch pack (108) to engage the said second clutch pack (108) with the third gear (109), the main shaft (102) receives rotational energy from the third gear (109) due to engagement of the second clutch pack (108) with the third gear (109), wherein the direction of rotation is counter clock-wise direction, furthermore, the speed reducing unit (113) receives the counter clock-wise rotational energy from the main shaft (102) through the drop gear unit (114), which operates the work vehicle in reverse direction. Furthermore, there exists no supply of hydraulic fluid to the clutch pack (107), hence engagement does not happen and no energy transfer occurs through clutch pack (107).
The present invention eliminates the mandatory need of multi-speed power take off or 2-speed immediate power take off and provides the output of the secondary shaft at 540 RPM catering to suitable application. Further, the present invention can be used as such in the vintage and old tractor’s transmission unit to maintain the same wheelbase of the work vehicle which makes the power shuttle transmission swapping with minimal component changes on the existing base with simple construction of transmission components.
It will be apparent to a person skilled in the art that the above description is for illustrative purposes only and should not be considered as limiting. Various modifications, additions, alterations, and improvements without deviating from the spirit and the scope of the invention may be made by a person skilled in the art.
LIST OF REFRENCE NUMERALS
100. Transmission housing
101. Driving unit
102. Main Shaft
103. Secondary shaft
104. First gear
105. Second gear
106. Clutch housing
107. First Clutch pack
108. Second clutch pack
109. Third gear
110. First hydraulic pipeline
111. Second hydraulic pipeline
112. Third hydraulic pipeline
113. Speed reducing unit
114. Drop gear unit
115. fourth gear
201 Idler gear shaft
202 Fifth gear
203 Sixth gear
204 Fly-wheel
205 Damper
116 Internal Manifold
117 External Manifold