FORM 2
THE PATENTS ACT 1970
(39 of 1970)
AND
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rulel3)
1. TITLE OF THE INVENTION:
"MULTI-SPEED POWER TAKE-OFF TRANSMISSION SYSTEM FOR
WORK VEHICLES"
2. APPLICANT:
(a) NAME: MAHINDRA & MAHINDRA LTD.
(b)NATIONALITY: Indian Company incorporated under the Companies Act, 1956
(c) ADDRESS: Gateway Building, Apollo Bunder, Mumbai - 400001, Maharashtra, India.
3. PREAMBLE TO THE DESCRIPTION:
The following specification particularly describes the invention and the manner in which it is to be formed.

FIELD OF THE INVENTION:
The present invention relates to a Power Take-Off (PTO) system used with agricultural and industrial applications, and more particularly concerned with a power take-off transmission system incorporating multi-rotational output speeds at power take-off output shaft.
BACKGROUND OF THE INVENTION:
Agricultural and industrial applications where vehicles such as tractors and other constructional vehicles are used for various mechanizations, it has been rigorously mandated that the power generated from the prime source such as internal combustion engine needs to be taken out apart from distributing to driving wheels by some means, such referred herein as power take-off. In order to transmit power from the combustion engine to power take-off shaft, various methods of power flow arrangements have been made in the past. One method of power take-off system is transferring direct power from engine via an additional clutch apart from the conventional clutch provided for transferring power to gear box. Another method is taking power from the gear box by connecting power take-off shaft directly to either counter shaft or main shaft of the gear box as per the requirement. Yet another method includes transfer of engine power directly therefrom using conventional clutch with some engaging means. All these methods are suitably incorporated along with the clutch housing and transmission housing suitably to be operated by the operator with help of a lever.
In most of the current tractor applications, this power take-off system is designed and developed to out the power from back side, front side and underside of the vehicle depends on the application for which the vehicle is specifically designed. Also, the power is taken out in two rotational speeds such as 540 and lOOOrpm in one direction. Some tractor may be provided with either 540 or 1000 rpm in clockwise direction and another speed in anticlockwise rotation. These two speeds are considered to be mandatory for any applications where an earth moving implements requires rotational energy apart from hitching on to the three-point linkage. It is also to be understood that engaging and disengaging the power flow from the engine to the power take-off shaft and selecting a

gear ratio between these two speeds are to be conveniently and comfortably operated by the operator.
Though these situations are handled and well established by diverse technological aspects and innovative alterations & adaptations, the current farm mechanizations demand innovative earth moving implements needing and other machineries which require rotational input energy from power take-off system in more than conventional two output speeds so as to work with different implements productively and effectively. Also, a complete and full-fledged power take-off system requires minimum a forward speed and a reverse speed so as to work with any power take-off driven implements or device productively. For example, when an implement such as rotavator is mounted on to the three-point linkage and derive rotational energy from the power take-off output shaft, as the field operation goes on, after some point, blades of the rotavator got stuck up with mud or other chaff, if in paddy field, and etc., and tend to gradually reduce speed of rotation and at the same time to overcome the resistance offered by this mud, the rotavator consumes more power that eventually consume engine power and thereby fuel. To avoid this saddening situation, the operator comes out of his seat and removes all mud and other particles. This is time consuming process and ultimately affects productivity for the day. To overcome this issue, manufacturers started to provide a reverse rotational speed as so as to remove the particles by the operator by sitting in his seat. To make this little more effective and do it in short span of time, it is decided to provide higher rotational speed so that the operator can remove the particle very quickly. All these customer friendly aspects, demand manufactures to come out with a work vehicle having more than conventional two rotational speeds.
At manufactures end, it is obvious that increasing output speeds of power take-off system calls for a sophisticated and a complete gear selection system like the conventional gear shifting system which further adds to cost in design and development of the vehicle. To avoid this, the shifting system may be simplified by providing more than one lever, but that will cause inconvenience to the operator.
Hence, the challenge lies in providing a power take-off system with three speeds of rotations comprising two forward rotational speeds and a reverse rotational speed

operated only with a single lever for engaging and disengaging the power take-off shaft with the engine power and selecting the gear ratio & rotation. Also, the three speed power take-off transmission system is to be incorporated within the available space of the transmission housing and should be compact, maintenance free and low cost system.
SUMMARY OF THE INVENTION:
According to an aspect of the present invention, a power take-off transmission system comprises a power take-off input shaft rotatably supported with clutch housing via bearing devices and one end of which is engaged with a first clutch plate to receive power from internal combustion engine or other power source. Said power take-off input shaft comprises a plurality of gears including a first drive gear and a second drive gear. The power take-off transmission system also comprises a power take-off main shaft rotatably supported with the clutch housing via bearing devices and adapted to freely and rotatably receive plurality of driven gears including a first driven gear and an adaptor, said adaptor having one end provided with splines adapted to engage with a second driven gear and freely and rotatably receive a plurality of driven gears including a third driven gear, said third driven gear receives power from the power take-off input shaft by engaging with a third drive gear which receives power from an idle gear through an idle shaft, said idle gear engaged with the first driven gear of the power take-off input shaft. Further comprises a power take-off hub splined with the power take-off main shaft and to engage and disengage with a plurality of collars including a first collar of said first driven gear, a second collar of said adaptor and a third collar of said third driven gear via a power takeoff shifting collar. Hence, during the operation, when the power take-off shifting collar engages the power take-off hub with the first collar, a first rotational speed is established at a power take-off output shaft, when the power take-off shifting collar engages the power take-off hub with the second collar, a second rotational speed is established at the power take-off output shaft, and when the power take-off shifting collar engages the power take-off hub with the third collar, a reverse rotational speed is established at the power take-off output shaft.
Referring to aforesaid description, the main objective of the present invention is to provide a multi-speed power take-off transmission system incorporated with agricultural

vehicles such as tractor and alike and industrial application where there is a need rotational mechanical energy in plurality of speeds. In agricultural vehicles, with the present invention, varied earth moving implements shall be worked with the work vehicles by providing power to the implement in different range of rotational speeds in forward direction as well as in reverse direction. This combination of multi-forward rotational speeds and reverse rotational speeds make the operator to work with the implements effectively and productively.
Another objective is to integrate the three speed power take-off transmission system with the existing power take-off transmission assembly within the available space and with no major modifications in the housing or other components. Also make the shifting system very simple and cost effective by using existing single shifting lever in spite of the three gear ratios.
Another aspect of the present invention may be the third drive gear shall be directly splined with the power take-off input shaft to have a third rotational output speed instead of reverse rotational output speed. Another optional feature is a second adaptor shall be disposed at the power take-off main shaft to have a fourth rotational output speed.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS:
Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail herein below with reference to the accompanying drawings, wherein:

FIG.l is a longitudinal section view of transmission body of a work vehicle incorporating a power take-off transmission system according to the present invention.
FIG.2 is an enlarged and longitudinal section view of the power take-off transmission system of FIG.l.
FIG.3 is cut section view of an idler gear assembly of FIG.l & F1G.2.
FIG.4 is an enlarged view of the power take-off transmission assembly of FIG.l & FIG.2
FIG.5 is a cut section view of the power take-off transmission system of FIG.2 configured to describe power flow of first forward rotational speed.
FIG.6 is cut section view of the power take-off transmission system of FIG.2 configured to describe power flow of second forward rotational speed.
FIG.7 is cut section view of the power take-off transmission system of FIG.2 configured to describe power flow of reverse rotational speed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT:
Nevertheless, the present invention is susceptible of embodiments in many different forms, the detailed description of the preferred embodiments and the corresponding drawings shown herein below are to be understood that the disclosure shall be deemed as an example of the principles of the invention and not intended to limit the invention to the specific embodiments shown and described. In the description below, like reference numerals are used to describe the same, similar or corresponding parts in the several views of FIG 1-7.
The present invention discloses a multi-speed power take-off transmission system having two forward rotational speeds and a reverse rotational speed operated with a single lever comprising a power take-off input shaft rotatably supported with a clutch housing via bearing devices and engaged with a first clutch plate to receive power from power source,

a power take-off main shaft rotatably supported with the clutch housing via bearing devices and adapted to freely and rotatably receive plurality of driven gears, the plurality of driven gears being a first driven gear, a second driven gear and a third driven gear, and a power take-off hub splined with the power take-off main shaft and to engage and disengage with plurality of collars of the plurality of driven gears via a power take-off shifting collar, the plurality of collars being a first collar, a second collar and a third collar; wherein a first forward rotational speed being established at a power take-off output shaft when the power take-off hub is engaged with the first collar, a second forward rotational speed being established at the power take-off output shaft when the power take-off hub is engaged with the second collar, and a reverse rotational speed being established at the power take-off output shaft when the power take-off hub is engaged with the third collar.
Referring to FIG. 1, a work vehicle such as tractor and alike has a transmission body (100) that is generally referred as 'skid' of the tractor and acts as a complete supporting structure for the tractor like what a chassis does for an on-road vehicle. The transmission body has a clutch housing (101) and a transmission housing (102), wherein the clutch housing encloses a flywheel (103), a clutch assembly (104) and the transmission housing (102) encloses a speed reduction transmission system (not shown) and a power take-off (PTO) transmission system (105) of the present invention. The transmission lay out disclosed along with the transmission body (100) is exemplary and is being merely considered herein for describing the power flow of the power take-off transmission system (105) from the flywheel (103) of prime source of energy such as internal. combustion engine to power take-off output shaft, and it should neither construed as part of the present invention nor limit the scope of the present invention, and 'the power' referred herein should be reckoned as "rotational mechanical energy". Accordingly, the clutch assembly (104) includes a first clutch plate (106) and a second clutch plate (107), wherein the second clutch plate (107) is splined with a speed reduction input shaft (108) to transfer the engine power from the flywheel (103) to speed reduction transmission system and the first clutch plate (106) is splined with an elongated power take-off input shaft (109) that is inserted over the speed reduction input shaft (108). In this typical transmission assembly, when the work vehicle is in operation, the power from engine is transferring to the speed reduction transmission system as well as the power take-off

transmission system (105) simultaneously, and when a clutch pedal is initially pressed, the second clutch plate (107) is disengaged from the flywheel (103) and stop engine power flowing from the flywheel (103) to the speed reduction transmission system but the engine power will still flow to the power take-off transmission system (105). Further actuation of the clutch pedal will disengage the engine power from the power take-off transmission system (105). Aforesaid description of method of engine power flow to the power take-off transmission system is exemplary and should not be limiting the scope of the present invention describing herein below.
Thus transferred engine power to the power take-off transmission system (105) is taken out at backward of the work vehicle at a power take-off output shaft (110) from a power take-off main shaft (111) through a power take-off coupling shaft (112), wherein the power take-off main shaft (111) input power to the power take-off output shaft (110) based on selection of gear ratio among forward rotational speeds and between forward rotational speed and reverse rotational speed- The power take-off output shaft (110) has a first end (110a) coupled with one end of the power take-off coupling shaft (112), which extends from a second end (111b) of the power take-off main shaft (111) along the clutch housing (101) and the transmission housing (102). Second end (110b) of the power take-off output shaft (110) is exposed outside of the backward end of the transmission housing (102) and provided with splines (110c) to removably connect with an earth moving implement (not shown) and transfer the engine power thereto to operate the implement. A coupling device (113) is provided for removably coupling the power takeoff output shaft (110) with the power take-off coupling shaft (112). The power take-off output shaft (110) is rotatably supported with the transmission housing (102) via a bearing device (114).
Referring to F1G.2, the elongated power take-off input shaft (109) is rotatably supported with clutch housing (101) at a first housing wall (115) and a second housing wall (116) via roller bearing devices (117). Section of the elongated power take-off input shaft (109) between the first housing wall (115) and the second wall housing (116) is provided with plurality of teeth (118) at outer circumference thereof, which is also referred as first drive gear, for engaging with a first driven gear (119) that is free-rotatably supported at adjacent to the first end (11 la) of the power take-off main shaft (111) via a first needle

bearing assembly (120) (shown in FIG.4). Backward end of the power take-off input shaft (109) is rigidly fixed with a second drive gear (121) to engage with a second driven gear (122) that is disposed at adjacent to the second end (111b) of the power take-off main shaft (111). Referring to FIG.3, an idler gear shaft (123) is rotatably supported with the clutch housing at third housing walls (124) via needle bearing devices. An idle gear (125) is rigidly fixed with the idle gear shaft (123) between the third housing walls (124). Backward end of the idle gear shaft (123) is fixed with a third drive gear (126) to engage with a third driven gear (127) which is free-rotatably disposed between the first driven gear (119) and the second driven gear (122) via a third needle bearing assembly (128) (shown in FIG.4).
Referring to FIG.2 and FIG.4, the power take-off main shaft (111) is rotatably supported with the clutch housing (101) with its first end (Ilia) at a fourth housing wall (129) and with its second end (11 lb) at a fifth housing wall (130) via a needle bearing device (131) a second roller bearing device (132), respectively. The power take-off main shaft (111) has two diameter sections throughout length thereof, wherein a first diameter section is along the first end (111 a) a second diameter section is along the second end (111b). Plurality of splines (133) is provided at the first diameter section where it conjoins with the second, diameter section to engage with a power take-off hub (134). Outer circumference of the power take-off hub (134) is also provided with splines (135). The first driven gear (119) has a first collar (136) also provided with splines having dimensional characteristic as same as the splines (135) of the power take-off hub (134). The first driven gear (119) is supported at the first diameter portion of the power take-off main shaft (111) so as to abut the first collar (136) thereof with the power take-off hub (134). An adaptor (137) is free-rotatably inserted over the second diameter of the power take-off main shaft (111) via a second needle bearing assembly (138). The adaptor (137) has backward end provided with splines (139) around its circumference and forward end provided with a second collar (140) having splines as same as splines (135). The second collar (140) abuts with the power take-off hub (134) and the spline (139) is engaged with the second driven gear (122). The third driven gear (127) has a third collar (141) having splines as same as the splines (135) and abut with the second collar (140) and free-rotatably supported over the adaptor (137) via the third needle bearing assembly (128). A spacer (142) is disposed between the second driven gear (122) and the third driven gear

(127) to arrest axial movement of the third driven gear (127). The power take-off main shaft has a substantial lengthy hole (11 Ic) along the axis from the first end (11 la) and branched to the first needle bearing assembly (120) via a first branch hole (11 Id) and to the second needle bearing assembly (138) via a second branch hole (1 lie) for lubricating the needle bearing assemblies (120 & 138).
The power take-off transmission system (105) has a power take-off shifting collar (143) having width same as the width of the power take-off hub (134) and provided with internal splines adapted to engage with the splines (135) of the power take-off hub (134). The power take-off shifting collar (143) has a first pair of limb (144) at the outer circumference to define a first annular groove (145) there between adapted to receive a shifting lever (not shown) for selecting a gear ratio and direction of rotation. Inner circumference of the power take-off shifting collar (143) also has a second pair of limb (146) having splines adapted to engage with the collars (136, 140 & 141) and the power take-off hub, and define a second annular groove (147) having width adapted to clear width of the second collar (140) while engaging the third collar (141) with the power take-off hub (134). The splines provided at the second pair of limbs are adapted to engage with the first collar (136), the second collar (140) and the third collar (141) and made to slide over the power take-off hub (134) and the collars (136, 140 & 141) to and fro.
In an another embodiment, the present invention discloses a method for engaging and disengaging the power take-off shaft with the engine power and selecting the gear ratio & rotation to accomplish two forward rotational speeds and a reverse rotational speed a multi-speed power take-off transmission system with a single lever. The multi-speed power take-off transmission system consists of a power take-off input shaft rotatably supported with a clutch housing via bearing devices and engaged with a first clutch plate to receive power from power source, a power take-off main shaft rotatably supported with the clutch housing via bearing devices and adapted to freely and rotatably receive plurality of driven gears and an adaptor, the plurality of driven gears being a first driven gear, a second driven gear and a third driven gear, and a power take-off hub splined with the power take-off main shaft and to engage and disengage with plurality of collars of the plurality of driven gears via a power take-off shifting collar, the plurality of collars being a first collar, a second collar and a third collar. A first forward rotational speed is

established at a power take-off output shaft when the power take-off hub is engaged with the first collar, a second forward rotational speed is established at the power take-off output shaft when the power take-off hub is engaged with the second collar, and a reverse rotational speed is established at the power take-off output shaft when the power take-off hub is engaged with the third collar.
Referring to FIG.2 and FIG.4, when the power take-off shifting collar (143) is in complete engagement only with the power take-off hub (134), during the operation of the work vehicle, even though the power take-off input shaft (109) transfer the mechanical rotational energy to the driven gears (119, 122 & 127), the power take-off main shaft (111) does not transfer the same mechanical energy to the power take-off output shaft (110) as the driven gears (119, 122 & 127) are free-rotatably supported and disposed in the power take-off transmission system (105) via needle bearing assemblies (120, 138 & 128). This stage refers to the neutral stage of the power take-off transmission system (105) according to the present invention.
Referring to FIG.4 and FIG.5, when the power take-off shifting collar (143) is made to engage both the power take-off hub (134) and the first collar (136), the power transferred from the first drive gear (118) to the first driven gear (119) is further transferred to the power take-off main shaft (111) though the power take-off hub (134) as it is splined with the power take-off main shaft (111) and eventually the power is getting transferred at the second end (110b) of the power take-off output shaft (110). This power is referred as 'first rotational speed' of the power take-off transmission system (105) according to the present invention.
Referring to FIG.4 and FIG.6, when the power take-off shifting collar (143) is made to engage both the power take-off hub (134) and the second collar (140), the power transferred from the second drive gear (121) to the second driven gear (122) is further transferred to the power take-off main shaft (111) though the power take-off hub (134) as it is splined with the power take-off main shaft (111) and eventually the power is getting transferred at the second end (110b) of the power take-off output shaft (110). This power is referred as 'second rotational speed' of the power take-off transmission system (105) according to the present invention. As diameter of the second driven gear (122) is smaller

than the first driven gear (119), the second rotational speed is higher than the first rotational speed.
Referring to FIG.4 and FIG.7, when the power take-off shifting collar (143) is made to engage both the power take-off hub (134) and the third collar (141), the power transferred from the first drive gear (118) to the idle gear (125) is further transferred to the power take-off main shaft (111) from the third drive gear (126) though the idle shaft (123) to the third driven gear (127) , and as the power take-off hub (134) is splined with the power take-off main shaft (111), eventually the power is getting transferred at the second end (110b) of the power take-off output shaft (110). This power is referred as 'reverse rotational speed' of the power take-off transmission system (105) according to the present invention.
Thus the power take-off transmission system according to the present invention derive three rotational speeds such as first rotational speed, second rotational speed and reverse rotational speed at the end of the power take-off output shaft in reference to the best method of foregoing construction and working principles. It will be readily appreciated that a person skilled in the art may carry out modifications to the invention disclosed hereinabove without departing from the scope thereof. Hence, the particular embodiments described in detail herein are illustrative only and are not limiting to the scope of the invention, and which is to be given the full breadth of the appended claims and any all equivalents thereof.

WE CLAIM,
1. A multi-speed power take-off transmission system (105) having two forward
rotational speeds and a reverse rotational speed operated with a single lever
comprising;
a power take-off input shaft (109) rotatably supported with a clutch housing (101) via bearing devices (117) and engaged with a first clutch plate(106) to receive power from power source,
a power take-off main shaft (111) rotatably supported with said clutch housing (101) via bearing devices (117) and adapted to freely and rotatably receive plurality of driven gears and an adaptor (137), said plurality of driven gears being a first driven gear (119), a second driven gear (122) and a third driven gear (127), and
a power take-off hub (134) splined with said power take-off main shaft (111) and to engage and disengage with plurality of collars of said plurality of driven gears via a power take-off shifting collar (143), said plurality of collars being a first collar (136), a second collar (140) and a third collar (141); wherein
a first forward rotational speed being established at a power take-off output shaft (110) when said power take-off hub (134) is engaged with said first collar (136), a second forward rotational speed being established at said power take-off output shaft (110) when said power take-off hub (134) is engaged with said second collar (140), and
a reverse rotational speed being established at said power take-off output shaft (110) when said power take-off hub (134) is engaged with said third collar (141).
2. The multi-speed power take-off transmission system (105) according to claim 1,
wherein said power take-off input shaft (109) comprises a plurality of gears
including a first drive gear (118) and a second drive gear (121).

3. The multi-speed power take-off transmission system (105) according to claims 1 & 2, wherein a section of said power take-off input shaft (109) between a first housing wall (115) and a second wall housing (116) is provided with plurality of teeth (118) at said first drive gear, for engaging with said first driven gear (119).
4. The multi-speed power take-off transmission system (105) according to claim 1, wherein said first driven gear (119) is free-rotatably supported at adjacent to first end (Ilia) of said power take-off main shaft (111) via a first needle bearing assembly (120).
5. The multi-speed power take-off transmission system (105) according to claim 1, wherein backward end of said power take-off input shaft (109) is rigidly fixed with said second drive gear (121) to engage with said second driven gear (122), disposed at adjacent to second end (11 lb) of said power take-off main shaft (111).
6. The multi-speed power take-off transmission system (105) according to claim 1, wherein said third driven gear (127) is free-rotatably disposed between said first driven gear (119) and said second driven gear (122) via a third needle bearing assembly (128).
7. The multi-speed power take-off transmission system (105) according to claims 1 & 6, wherein said third driven gear (127) is engaged with an idle gear shaft (123), fixed with a third drive gear (126) at the backward end.
8. The multi-speed power take-off transmission system (105) according to claims 1, 4 & 5, wherein said power take-off hub (134) is engaged with said power take-off main shaft (111) at first diameter section at said first end (Ilia) by means of plurality of splines (133) and conjoined with second diameter section at said second end (111b).

9. The multi-speed power take-off transmission system (105) according to claim 1, wherein said power take-off hub (134) is abutted with said first collar (136) of said first driven gear (119) supported at the first diameter portion of said power take-off main shaft (111).
10. The multi-speed power take-off transmission system (105) according to claim 1, wherein said adapter (137) is free-rotatably inserted at said power take-off main shaft (111) via a second needle bearing assembly (138).
11. The multi-speed power take-off transmission system (105) according to claim 1, wherein backward end of said adaptor (137) is provided with splines (139) around its circumference whereas forward end is provided with said second collar (140) having splines as same as splines (135).
12. The multi-speed power take-off transmission system (105) according to claims 1 and 13, wherein said power take-off hub (134) is abutted with said second collar (140) and said adaptor (137) is engaged with said second driven gear (122) through splines (139).
13. The multi-speed power take-off transmission system (105) according to claims 1 and 13, wherein said third driven gear (127) has said third collar (141) having splines as same as the splines (135) and abut with the second collar (140) and free-rotatably supported over said adaptor (137) via the third needle bearing assembly (128).
14. The multi-speed power take-off transmission system (105) according to claim 1, wherein said power take-off shifting collar (143) is provided with internal splines adapted to engage with splines (135) of said power take-off hub (134).

15. The multi-speed power take-off transmission system (105) according to claim 1, wherein said power take-off shifting collar (143) is provided with a first pair of limb (144) at the outer circumference to define a first annular groove (145) adapted to receive a shifting lever for selecting a gear ratio and thereby direction of rotation.
16. The multi-speed power take-off transmission system (105) according to claim 1, wherein said power take-off shifting collar (143) is provided with a second pair of limb (146) having splines adapted to engage with said collars (136, 140 & 141) and said power take-off hub (134).