FIELD
The present disclosure relates to the field of tractors. In particular, the present
disclosure relates to the field of power take-off arrangements for a tractor. More
specifically, the present disclosure also relates to an addition of safety feature to
5 the power take-off arrangement.
BACKGROUND
A power take-off typically refers to any of the several methods for taking power
from a power source, such as a running engine, and transmitting it to an
application such as an attached implement or separate machines. In agriculture,
10 operations such as tilling and ploughing are nowadays performed using
mechanized tools that derive power from the engine via a power take-off shaft.
More specifically, at one operative end, the power take-off shaft is coupled to the
engine via an input power shaft to receive the mechanical drive from the engine,
and the downstream equipment for performing the different operations are
15 coupled to another operative end of the power take-off shaft. Conventionally, the
method of coupling the input power shaft with the power take-off shaft involves
directly engaging the input power shaft and the power take-off while the input
power shaft is still rotating. This causes the improper meshing of the gears or
splined coupling configured at the mating ends of the input power shaft and the
20 power take-off, which is accompanied by severe vibrations at high engine RPM.
This is not desired, as the vibrations severely impact the service life of the gears
or splined coupling or may even cause the complete failure of the mating parts.
There is, therefore, a need for a power take-off arrangement, which has smooth
meshing or engagement of the input power shaft and the power take-off is not
25 accompanied by severe vibrations.
3
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment
herein satisfies are as follows:
An object of present disclosure is to provide an additional safety feature for a
power take-off arrangement for a tractor, 5 in which the engagement of the input
power shaft and the power take-off shaft coupling is smooth, as compared to the
conventional power take-off arrangements.
Another object of the present disclosure is to provide a power take-off
arrangement for a tractor, in which the engagement of the input power shaft with
10 the power take-off shaft is accompanied by substantially reduced vibrations, as
compared with the conventional power take-off arrangements.
Other objects and advantages of the present disclosure will be more apparent from
the following description when read in conjunction with the accompanying figure,
which are not intended to limit the scope of the present disclosure.
15 SUMMARY
The present disclosure envisages a power take-off arrangement for a tractor
having an input power shaft coupled with an engine of the tractor and a power
take-off shaft engageable with the input power shaft to receive mechanical drive.
The tractor also has a handle for facilitating a selective engagement between the
20 input power shaft and the power take-off shaft. The arrangement comprises a
clutch mechanism for facilitating the selective engagement between the input
power shaft and the power take-off shaft. The clutch mechanism comprises a
clutch pedal for actuating the clutch mechanism, and a plurality of linkages
configured to be displaced by the clutch pedal. In a first normal position of the
25 clutch pedal, the clutch mechanism is engaged and the plurality of linkages hold
the handle in a locked and non-actuable state, thereby preventing engagement
between the input power shaft and the power take-off shaft. In a second actuated
4
position of the clutch pedal, the clutch mechanism is disengaged and the plurality
of linkages is displaced to render the handle in an unlocked and actuable state,
wherein on actuation, the handle facilitates the selective engagement between the
input power shaft and the power take-off shaft.
In an embodiment, the plurality of linkages 5 comprises first tie rod, having an
operative top end and an operative bottom end, is pivotally coupled with the
clutch pedal at the operative top end thereof. A clutch actuation shaft defines a
first end and a second end, wherein the first end of clutch actuation shaft is
operatively coupled with the operative bottom end of the first tie rod. A second tie
10 rod has an operative front end and an operative rear end, wherein the operative
rear end is operatively coupled with the second end of the clutch actuation shaft.
A fulcrum lock is coupled with the operative front end of the second tie rod and
configured to hold the handle in the locked and the non-actuable state when the
clutch pedal is in the engaged position.
15 In another embodiment, the arrangement further comprises a locking pin
configured on the handle. The fulcrum lock has a C-shaped profile configured to
connect with the locking pin for holding the handle in the locked and the nonactuable
state.
In another embodiment, the clutch actuation shaft has an L-shaped configuration
20 defining the first end and the second end.
In another embodiment, the arrangement further comprises a biasing element
provided on the clutch pedal for returning the clutch pedal to an unpressed state
after the pressing force is removed from the clutch pedal. In an embodiment, the
biasing element is a spring.
25 BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A power take-off arrangement for a tractor, of the present disclosure, will now be
described with the help of the accompanying drawing, in which:
5
Fig. 1 illustrates a schematic view of the power take-off arrangement, in
accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION
Fig. 1 illustrates a schematic view of a power take-off arrangement for a tractor
100 (hereinafter referred to as arrangement 5 100). The arrangement 100 comprises
an input power shaft 102 coupled with an engine (not shown in figures) of the
tractor (not shown in figures). The input power shaft 102 receives a mechanical
drive from the engine, and the same mechanical drive is then transferred to a
power take-off shaft 104. More specifically, the power take-off shaft 104 is
10 selectively engageable with the input power shaft 102 to receive a mechanical
drive. In the present disclosure, selective engagement refers to the feature that the
power take-off shaft 104 can either kept be engaged or disengaged with the input
power shaft 102. The selective engagement of the input power shaft 102 and the
power take-off shaft 104 is facilitated by a handle 106.
15 In a first operative configuration, at an engaged position of a clutch (not shown in
figures) of the tractor, the handle 106 is in a locked and a non-actuable state,
wherein in the locked and non-actuable state the power take-off shaft 104 and the
input power shaft 102 are disengaged. More specifically, it is the locking of the
handle 106 that prevents the engagement between the power take-off shaft 104
20 and the input power shaft 102 as the shaft is rotating at the speed of the engine
RPM. The disengaged configuration of the power take-off shaft 104 and the input
power shaft 102 prevents the transmission of the mechanical drive to the power
take-off shaft 104, and therefore, to the end equipment.
In a second operative configuration, at a disengaged position of the clutch, the
25 handle 106 is in an unlocked and an actuable state, thereby facilitating the
selective engagement between the input power shaft 102 and the power take-off
shaft 104 subsequent to actuation. In Fig. 1, the actuated state of the handle 106 is
shown in dotted lines referred to by the numeral 106’. On actuation, the handle
106 facilitates the engagement between the input power shaft 102 and the power
6
take-off shaft 104. In an embodiment, the ends of the input power shaft 102 and
the power take-off shaft 104 are provided with complementary gears or splined
coupling, which are configured to mate with each other.
In an embodiment, the arrangement 100 further comprises clutch mechanism 107.
The clutch mechanism 107 comprises a clutch 5 pedal 108 for actuating the clutch
mechanism 107. The clutch mechanism 107 comprises a plurality of linkages. The
plurality of linkages comprises a first tie rod 110. The clutch pedal 108 is
mechanically coupled with the first tie rod 110 having an operative top end 110A
and an operative bottom end 110B. More specifically, the first tie rod 110 is
10 pivotally coupled with the clutch pedal 108 at the operative top end 110A thereof.
The pivotal connection between the first tie rod 110 and the clutch pedal 108 is
facilitated by a pivot 112.
The plurality of linkages further comprises a clutch actuation shaft 114 that
defines a first end 114A and a second end 114B, wherein the first end 114A of
15 clutch actuation shaft 114 is operatively coupled with the operative bottom end
110B of the first tie rod 110. The plurality of linkages further comprises a second
tie rod 116 having an operative front end 116A and an operative rear end 116B,
wherein the operative rear end 116B is operatively coupled with the second end
114B of the clutch actuation shaft 114. More specifically, the clutch actuation
20 shaft 114 has an L-shaped profile that defines the first end 114A and the second
end 114B. It is to be noted that in the present disclosure, the direction pointing
from the clutch actuation shaft 114 towards the power take-off shaft 104 is termed
as the operative front, and as such, the operative rear is the opposite direction.
The plurality of linkages further comprises a fulcrum lock 118 that is coupled with
25 the operative front end 116A of the second tie rod 116 and configured to hold the
handle 106 in the locked and the non-actuable state when the clutch is in the
engaged position or the clutch pedal 108 is in an unpressed state. In an
embodiment, the clutch mechanism 107 further comprises a locking pin 106A
configured on the handle 106. The fulcrum lock 118 has a C-shaped profile
7
configured to connect with the locking pin 106A for holding the handle 106 in the
locked and the non-actuable state when the clutch pedal 108 is in the engaged
position.
In another embodiment, the arrangement 100 further comprises a biasing element
120 provided on the clutch pedal 108 for 5 returning the clutch pedal 108 to the
unpressed state after the pressing force is removed from the clutch pedal 108. In
an embodiment, the biasing element 120 is a spring.
The operative configuration of the arrangement 100 is hereinafter described with
reference to Fig. 1. In the first operative configuration, the clutch pedal 108 is
10 unpressed. When the clutch pedal 108 is unpressed, there is no actuation force
acting on the first tie rod 110, the clutch actuation shaft 114, the second tie rod
116, and the fulcrum lock 118. Since there is no actuation force acting on the
aforementioned elements of the arrangement 100, the positions of said elements is
denoted by solid lines in Fig. 1. It can be seen in Fig. 1 that the fulcrum lock 118
15 is abutting the locking pin 106A of the handle 106 to hold the handle 106 in the
locked state.
In the second operative configuration, the clutch pedal 108 is pressed. The pressed
state of the clutch pedal 108 is denoted by dotted lines referred by the numeral
108’. When the clutch pedal 108 is pressed, the input power shaft 102 is
20 disengaged from the engine and becomes stationary. At the same time, an
operative vertical force acts on the first tie rod 110 by the virtue of the pivotal
coupling between the clutch pedal 108 and the first tie rod 110. The vertical force
causes displacement of the first tie rod 110, which in turn displaces the clutch
actuation shaft 114. The L-shaped profile of the clutch actuation shaft 114
25 facilitates the supply of force in the operative front direction, thereby pushing the
second tie rod 116 for pivotally moving the fulcrum lock 118 in anti-clockwise
direction. The pivotal movement of the fulcrum lock 118 disconnects or
disengages the C-shaped portion of the fulcrum lock 118 with the locking pin
106A. Once disengaged, the handle 106 can be actuated in the position 106A,
8
thereby facilitating the engagement of the power take-off shaft 104 and the input
power shaft 102. More specifically, during the engagement, both the power takeoff
shaft 104 and the input power shaft 102 are aligned, and as such, a smooth
engagement is achieved between the power take-off shaft 104 and the input power
shaft 102 using the arrangement 100 of the 5 present disclosure. It is to be noted that
the input power shaft 102 does not receive the mechanical drive from the engine
when the clutch pedal 108 is disengaged, thereby facilitating the smooth
engagement between the power take-off shaft 104 and the input power shaft 102.
The smooth engagement between the power take-off shaft 104 and the input
10 power shaft 102 facilitates proper meshing of the gears or splines configured
thereon. Such an engagement of the power take-off shaft 104 and the input power
shaft 102 is not accompanied by severe vibrations, as was the case with the
conventional power take-off arrangements. The substantially reduced vibrations
improve the service life of the gear or splines configured on the power take-off
15 shaft 104 and the input power shaft 102.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages
including, but not limited to, a power take-off arrangement for a tractor, in which:
 the engagement of the input power shaft with the power take-off shaft is
20 smooth, as compared with the conventional power take-off arrangements;
and
 the engagement of the input power shaft with the power take-off shaft is
accompanied by substantially reduced vibrations, as compared with the
conventional power take-off arrangements.:
25 The disclosure has been described with reference to the accompanying
embodiments which do not limit the scope and ambit of the disclosure. The
description provided is purely by way of example and illustration.
9
The embodiments herein and the various features and advantageous details thereof
are explained with reference to the non-limiting embodiments in the following
description. Descriptions of well-known components and processing techniques
are omitted so as to not unnecessarily obscure the embodiments herein. The
examples used herein are intended merely 5 to facilitate an understanding of ways
in which the embodiments herein may be practiced and to further enable those of
skill in the art to practice the embodiments herein. Accordingly, the examples
should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully revealed the
10 general nature of the embodiments herein that others can, by applying current
knowledge, readily modify and/or adapt for various applications such specific
embodiments without departing from the generic concept, and, therefore, such
adaptations and modifications should and are intended to be comprehended within
the meaning and range of equivalents of the disclosed embodiments. It is to be
15 understood that the phraseology or terminology employed herein is for the
purpose of description and not of limitation. Therefore, while the embodiments
herein have been described in terms of preferred embodiments, those skilled in the
art will recognize that the embodiments herein can be practiced with modification
within the spirit and scope of the embodiments as described herein.
20 Throughout this specification the word “comprise”, or variations such as
“comprises” or “comprising”, will be understood to imply the inclusion of a stated
element, integer or step, or group of elements, integers or steps, but not the
exclusion of any other element, integer or step, or group of elements, integers or
steps.
25 The use of the expression “at least” or “at least one” suggests the use of one or
more elements or ingredients or quantities, as the use may be in the embodiment
of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has
been included in this specification is solely for the purpose of providing a context
10
for the disclosure. It is not to be taken as an admission that any or all of these
matters form a part of the prior art base or were common general knowledge in the
field relevant to the disclosure as it existed anywhere before the priority date of
this application.
The numerical values mentioned for the 5 various physical parameters, dimensions
or quantities are only approximations and it is envisaged that the values
higher/lower than the numerical values assigned to the parameters, dimensions or
quantities fall within the scope of the disclosure, unless there is a statement in the
specification specific to the contrary.
10 While considerable emphasis has been placed herein on the components and
component parts of the preferred embodiments, it will be appreciated that many
embodiments can be made and that many changes can be made in the preferred
embodiments without departing from the principles of the disclosure. These and
other changes in the preferred embodiment as well as other embodiments of the
15 disclosure will be apparent to those skilled in the art from the disclosure herein,
whereby it is to be distinctly understood that the foregoing descriptive matter is to
be interpreted merely as illustrative of the disclosure and not as a limitation.

WE CLAIM:
1. A power take-off arrangement for a tractor having an input power shaft
coupled with an engine of said tractor and a power take-off shaft engageable
with said input power shaft to receive mechanical drive, said tractor having a
handle for facilitating a selective engagement 5 between said input power shaft
and said power take-off shaft, said arrangement comprising:
a clutch mechanism for facilitating said selective engagement between
said input power shaft and said power take-off shaft, said clutch mechanism
comprising:
10 a clutch pedal for actuating said clutch mechanism;
a plurality of linkages configured to be displaced by said clutch
pedal, wherein:
in a first normal position of said clutch pedal, said clutch
mechanism is engaged and said plurality of linkages hold said handle
15 in a locked and non-actuable state, thereby preventing engagement
between said input power shaft and said power take-off shaft; and
in a second actuated position of said clutch pedal, said
clutch mechanism is disengaged and said plurality of linkages is
displaced to render said handle in an unlocked and actuable state,
20 wherein on actuation, said handle facilitates said selective engagement
between said input power shaft and said power take-off shaft.
2. The arrangement as claimed in claim 1, wherein said plurality of linkages
includes:
a first tie rod having an operative top end and an operative bottom
25 end, said first tie rod pivotally coupled with said clutch pedal at said operative
top end;
a clutch actuation shaft defining a first end and a second end, said first
end of clutch actuation shaft operatively coupled with said operative bottom
end of said first tie rod;
12
a second tie rod having an operative front end and an operative rear
end, wherein said operative rear end is operatively coupled with said second
end of said clutch actuation shaft; and
a fulcrum lock coupled with said operative front end of said second tie
rod and configured to hold said handle in 5 said locked and non-actuable state
when said clutch pedal is in said engaged position.
3. The arrangement as claimed in claim 2, further comprising a locking pin
configured on said handle.
4. The arrangement as claimed in claim 3, wherein said fulcrum lock has a C10
shaped profile configured to connect with said locking pin for holding said
handle in said locked and said non-actuable state.
5. The arrangement as claimed in claim 2, wherein said clutch actuation shaft has
an L-shaped configuration defining said first end and said second end.
6. The arrangement as claimed in claim 2, further comprising a biasing element
provided on said clutch pedal for returning said clutch pedal to an unpressed
state after the pressing force is removed from said clutch pedal.
7. The arrangement as claimed in claim 2, wherein said biasing element is a
spring.