DESC:FIELD OF INVENTION

The present invention relates to the vineyard spraying operations using tractors. In particular, the present invention relates to the mechanism for transferring power from the tractor PTO to the sprayer. More particularly, the present invention relates to the propeller shaft configured for facilitating only positive power drive from the tractor PTO to the sprayer.

BACKGROUND OF THE INVENTION

In Vineyard Spraying applications, the tractor operator sets the PTO rpm to achieve the desired travel speed for operating the sprayer and ensures the accurate pressure thereof, as required, e.g. about 2 bar.

When the operator presses the clutch pedal for shifting a gear, a clashing noise generated by the sprayer rotations is heard and the drive is continuously passed through the PTO shaft. Hence, the gear shifting operation is not possible until the sprayer is stopped.

PRIOR ART

Patent application published as US 4693333 A discloses a power transmission apparatus for vehicles provided with a front wheel driving device for connecting an output shaft of a power unit to front wheels and a rear wheel driving device for connecting the output shaft to rear wheels, wherein a unidirectional clutch is provided in the front wheel driving device, which clutch comprises an outer member, an inner member and a clutch roller, and is capable of transmitting a driving force only in one direction from a power unit side to a front wheel side.

Although, the concept of unidirectional shaft is generally known and is widely used in the industry, the construction of the unidirectional propeller shaft disclosed in this publication is quite different from that disclosed in the present patent application.

Patent application published as US 1736064 A discloses a unidirectional driving mechanism for a recording device which is equally responsive to movement of a given member in either direction, and in its more specific aspect is intended to be used in ship’s instruments, wherein registering means is actuated by propeller shaft movement with a degree of responsiveness dependent upon both the speed and number of propeller revolutions, this mechanism can generally be used in instruments for indicating or recording in response to either the speed or number of revolutions of the rotatable member.

DISADVANTAGES WITH THE PRIOR ART

The following are the disadvantages with the prior art discussed above:

During the spraying application, the operator frequently requires stopping the tractor. However, even after pressing the clutch and brake pedals, the tractor could not be stopped immediately because the drive is continuously given from the sprayer until the sprayer impeller momentum is stopped.

Therefore, there is an existing need for devising a mechanism for facilitating the tractor to be sudden stopped, irrespective of whether the sprayer momentum has completely stopped or not.

DESCRIPTION OF THE INVENTION

A unidirectional sprayer propeller shaft is developed in accordance with the present invention which to replace the conventional propeller shaft by restricting the impeller momentum from being passed to the tractor driveline, which earlier caused tractor to move forward even after pressing both clutch and brakes.

With this new mechanism, the tractor operator/driver can easily shift any gear without generating any clashing noise. This unidirectional propeller shaft transfers only a positive drive from the tractor PTO to the sprayer.
In this new mechanism, whenever tractor is stopped by using the clutch and brakes, the drive will not pass from the tractor-PTO to the sprayer, because it starts to slip the coupling due to the slip mechanism provided therein.

The mechanism is configured such that the propeller shaft transfers the drive, both in forward and reverse drive, from the tractor PTO to the spraying implement. With the pressed clutch, the driver can shift any gear without making any clashing noise. So, now with both clutch and brakes pressed, the tractor stops moving further and will not move forward even though the sprayer shaft / impeller continues to rotate. This facilitates an easy sprayer operation, particularly on turnings or while reversing and also on stopping the tractor in between, whenever required.

The technical advantages of the mechanism configured in accordance with the present invention, are as under:

• Substantial productivity enhancement.

• Ease of Operation, since stopping of tractor within a desired distance is made possible, which was earlier a major concern in sprayer vineyards because of the probability of the tractor hitting a tree or obstacle while taking a turn.

The improvement involves:

- Rotavator Shaft Cross is modified at the shear bolt side.

- Shear bolt mounting lobe is removed.

- Oval PTO lock-end is made circular (approx. 8.7 cm overall diameter) by removing the unnecessary shear bolt groove.

- Milling the earlier circular PTO lock-end cut for making 11 (square) teeth with 15 mm depth, 12 mm width and having 12 mm teeth to teeth distance.

- 9 cm diameter circular cap is made, and 4 locking guides are fitted on the cap.
- Circular cap is welded on the outer tube yoke for the propeller shaft.

- Mechanism is provided on the outer tube yoke for the propeller shaft for inserting the balls in the shaft groove for bearing purpose.

- The propeller shaft rotations are stopped/locked with the help of circular cap seated on the machined teeth and provided with spring loaded locking mechanism to restrict the clockwise or anticlockwise rotations of the PTO shaft.

- Spring loaded lock pins provided with spring placed at the PTO end.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide a mechanism for facilitating to stop tractor, even when spraying shaft/impeller continues rotating.

Another object of the present invention is to provide a mechanism with an improved propeller shaft for ease of spraying operation by a tractor without any clashing noise while shifting gears.

Still another object of the present invention is to provide a mechanism with an improved propeller shaft for ease of gear shifting during spraying operations even without complete stoppage of the sprayer impeller shaft.

Yet another object of the present invention is to provide a mechanism for ease of gear shifting, particularly while turning or reversing as well as on sudden stopping of the tractor in between.

A still further object of the present invention is to provide a mechanism equipped with a unidirectional propeller shaft to facilitate only a positive drive from the tractor PTO to the sprayer.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a slip mechanism with a unidirectional propeller shaft for sprayer operation in tractors, the slip mechanism comprising a unidirectional propeller shaft to transfer positive power drive noiselessly from the tractor PTO to the sprayer attached thereto by restricting the impeller momentum from being passed to the tractor driveline by stopping the tractor even without complete stoppage of the sprayer rotations.

Typically, the slip mechanism is a spring-loaded mechanism comprises:

• a tractor-side PTO yoke with a unidirectional propeller shaft assembly;

• an outer tube yoke shaft with a circular cap therefor;

• a spring loaded locking pin;

• a spring loaded PTO shaft locking pin;

• at least one grease nipple;

• a plurality of hardened metal balls for bearing end; and

• an improved rotavator cross having a shear bolt side thereof;

wherein the rotavator cross is configured without the mounting lobe on the shear bolt side thereof, the shear bolt side having PTO lock-end provided with a plurality of teeth thereon.

Typically, the circular cap comprises a plurality of locking guides fitted on the circumference thereof, preferably four locking guides uniformly spaced apart thereon.

Typically, the circular cap is joined to the outer tube yoke shaft, preferably by means of welding.

Typically, the grease nipple is removed for inserting the hardened metal balls in a groove provided in the propeller shaft for providing a bearing support in the unidirectional propeller shaft assembly.

Typically, the locking pin locks the sprayer shaft with the PTO shaft of the tractor.

In an embodiment of the present invention, a slip mechanism is provided with a unidirectional propeller shaft for sprayer operation in tractors, the slip mechanism comprising:

• a tractor-side PTO yoke with a unidirectional propeller shaft assembly;

• an outer tube yoke shaft joined by means of welding with a circular cap therefor; the cap having four locking guides fitted uniformly spaced apart on the circumference thereof;

• a spring loaded locking pin;

• a spring loaded PTO shaft locking pin;

• at least one grease nipple detachably fitted in a grease nipple hole;

• a plurality of hardened metal balls for bearing end and inserted in a grease hole for providing a bearing support; and

• an improved rotavator cross having a shear bolt side thereof;

wherein the rotavator cross is configured without the mounting lobe on the shear bolt side thereof, the shear bolt side having PTO lock-end provided with a plurality of teeth thereon.

Typically, the hardened metal balls are inserted in a groove provided in the propeller shaft through the grease nipple hole to provide a bearing support in the unidirectional propeller shaft assembly.
In accordance with the present invention, there is also provided a method for stopping the tractor by means of the slip mechanism as claimed in anyone of the claims 1 to 8, wherein the mechanism is operated to cut-off the drive by pressing the clutch and brake pedals to noiselessly preventing the power transfer from the sprayer to the tractor driveline to disable the tractor from moving forward.

Typically, the slip mechanism with the unidirectional propeller shaft is operated to noiselessly transfer the positive power drive from the tractor PTO to the sprayer attached thereto by restricting the impeller momentum to pass from the sprayer to the tractor driveline by stopping the tractor irrespective of complete stoppage of the sprayer rotations.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings, in which:

Figure 1 shows an exploded view of the tractor’s PTO shaft.

Figure 2 shows a conventional rotavator cross having a mounting lobe at the shear bolt side thereof.

Figure 3 shows the improved rotavator cross without the mounting lobe at its shear bolt side to be assembled into the unidirectional propeller shaft assembly of Fig. 1.

Figure 4a shows the turned rotavator cross of Fig. 4.

Figure 4b shows the turned rotavator cross of Fig. 5a after milling teeth thereon.

Figure 5a shows the turned circular cap to be welded on the outer yoke to be assembled into the propeller shaft assembly of Fig. 4.

Figure 5b shows the location of the outer yoke for inserting balls into the propeller shaft groove for forming a bearing support in the propeller shaft assembly of Fig. 4.

Figure 6a shows the stopping/locking the rotations of the propeller shaft with the help of the circular cap of Fig. 6a to be seated on machined teeth shown in Fig. 5b.

Figure 6b shows the spring-loaded mechanism to restrict the rotations of the PTO shaft and placed at the tractor PTO end.

Figure 6c shows a typical locking pin which is spring-loaded by using a spring thereon.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, the mechanism comprising an improved propeller shaft configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention in any way.

Figure 1 shows an exploded view of the tractor’s PTO shaft assembly having a slip mechanism configured in accordance with the present invention configured provided with an improved unidirectional propeller shaft for performing sprayer operation therein. It includes a tractor-side PTO yoke 110, an outer tube yoke shaft 120, a circular cap 130 for outer tube yoke shaft 120, a spring-loaded locking pin 140, a spring-loaded PTO shaft locking pin 150, a grease nipple 155, and a plurality of metallic balls 160 for bearing end. Here, the tractor-side PTO yoke 110 is inserted into the circular cap 130 of the outer tube yoke shaft 120 and the grease nipple 155 is removed therefrom to insert balls 160 through the grease nipple hole and finally the grease nipple 155 is refitted on the outer tube yoke shaft 120.

Figure 2 shows a conventional rotavator cross 70 having a mounting lobe 75 at the shear bolt side thereof.
Figure 3 shows the improved rotavator cross 170 without the mounting lobe at its shear bolt side 180 to be assembled into the unidirectional propeller shaft 100 assembly of Fig. 1.

Figure 4a shows the turned rotavator cross 170 of Fig. 4. An oval PTO lock-end 180 is made circular by turning on lathe machine and preferably has 8.7 cm diameter.

Figure 4b shows the turned rotavator cross 170 of Fig. 5a after milling teeth 172 thereon. The turned circular PTO lock-end 180 is milled, preferably with 11 square teeth of 10mm depth, 12mm width and 12mm circular pitch/tooth to tooth distance.

Figure 5a shows the turned circular cap 130 to be welded on the outer tube yoke shaft 120 to be assembled into the unidirectional propeller shaft assembly 110 of Figure 3. Here, a circular cap 130, preferably of 9 cm diameter is turned and four (4) locking guides 135 are fitted thereon, before welding the circular cap 130 on the outer tube yoke shaft 120.

Figure 5b shows the location of the grease nipple hole 155 provided in the outer tube yoke shaft 120 for inserting a plurality of balls, preferably hardened metallic balls 160 into the propeller shaft groove 132 (Fig. 5a) for forming a bearing support in the unidirectional propeller shaft assembly 110 of Fig. 3.

Figure 6a shows the unidirectional propeller shaft 110 with rotations thereof stopped/locked with the help of the circular cap 130 of Fig. 5a to be seated on milled teeth 172 shown in Fig. 5b.

Figure 6b shows the spring-loaded slip mechanism to restrict the PTO shaft rotations either in clockwise or anticlockwise directions and placed on the tractor PTO end duly marked with the locations of the locking pins 140 locked thereon. The PTO lock 140 with the turned circular PTO lock-end 172 is milled with teeth. A circular cap 130, preferably of 9 cm diameter is turned and four (4) locking guides 135 are fitted thereon, before welding the circular cap 130. The locking pin 150 locks the sprayer shaft with tractor PTO shaft.
Figure 6c shows a typical locking pin 140 spring-loaded by using spring thereon.

WORKING OF THE INVENTION

The function of the propeller shaft 100 is to transfer the power from the tractor PTO to the sprayer PTO. In accordance with the present invention, the mechanism configured with the improved propeller shaft facilitates to impart a positive drive for sprayer functioning.

However, whenever tractor is required to be stopped by pressing the clutch and brake pedals, the drive is prevented from passing from the sprayer to the tractor driveline, thus disables the tractor from moving forward.

This is achieved by providing a slip-mechanism, which immediately cuts off the drive with the tractor operator/driver pressing the clutch and brake pedals.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The mechanism with the improved propeller shaft assembly configured in accordance with the present invention has the following technical and economic advantages:

• Enhances customer satisfaction during sprayer application.

• Unidirectional propeller shaft offered as standard fitment in sprayer application makes the product competitive in the market.

• Propeller shaft transfers only positive working drive from Tractor PTO to sprayer.

• Whenever tractor is being stopped by pressing the clutch and brake pedals, the drive is not passed from sprayer to tractor PTO as it starts slipping due to the slip mechanism. Provided therein.

• Mechanism can transfer drive from the tractor PTO to implement - both in forward and reverse drive.
• With clutch pressed, the tractor driver/operator can shift any gear without making any clashing noise.

• By pressing both the clutch and brake pedals, the tractor movement stops completely, and it does not move forward, even though the sprayer shaft is rotating.

• Ease of sprayer operation on turnings, reversing and stoppages in between.

• Substantial productivity enhancement.

• Ease of Operation, since stopping of tractor within a desired distance is made possible, which was earlier a major concern in sprayer vineyards because of the probability of the tractor hitting a tree or obstacle while taking a turn.

The foregoing description of the specific embodiments will so fully reveal the 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 distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

The description provided herein is purely by way of example and illustration. The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention.

The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification.

It is to be 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, the skilled person will recognize that the embodiments herein can be practiced with modification within the spirit and scope of embodiments described herein.

Therefore, the skilled person can easily make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies, assemblies and in terms of the size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification, the word “comprise” or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention. ,CLAIMS:We claim:

1. A slip mechanism with a unidirectional propeller shaft for sprayer operation in tractors, said slip mechanism comprising a unidirectional propeller shaft to transfer positive power drive noiselessly from the tractor PTO to the sprayer attached thereto by restricting the impeller momentum from being passed to the tractor driveline by stopping the tractor even without complete stoppage of the sprayer rotations.

2. Slip mechanism as claimed in claim 1, wherein said mechanism is a spring-loaded mechanism comprising:

• a tractor-side PTO yoke with a unidirectional propeller shaft assembly (110);

• an outer tube yoke shaft (120) with a circular cap (130) therefor;

• a spring loaded locking pin (140);

• a spring loaded PTO shaft locking pin (150);

• at least one grease nipple (155);

• a plurality of hardened metal balls (160) for bearing end; and

• an improved rotavator cross (170) having a shear bolt side (180) thereof;

wherein said rotavator cross (170) is configured without the mounting lobe on said shear bolt side (180) thereof, said shear bolt side (180) having PTO lock-end (172) provided with a plurality of teeth thereon.

3. Slip mechanism as claimed in claim 2, wherein said circular cap (130) comprises a plurality of locking guides (135) fitted on the circumference thereof, preferably four locking guides (135) uniformly spaced apart thereon.

4. Slip mechanism as claimed in claim 2, wherein said circular cap (130) is joined to said outer tube yoke shaft (120), preferably by means of welding.

5. Slip mechanism as claimed in claim 2, wherein said grease nipple (155) is removed for inserting said hardened metal balls (160) in a groove (132) provided in said propeller shaft (110) for providing a bearing support in said unidirectional propeller shaft assembly.

6. Slip mechanism as claimed in claim 2, wherein said locking pin (150) locks the sprayer shaft with the PTO shaft of the tractor.

7. A slip mechanism with a unidirectional propeller shaft for sprayer operation in tractors, said slip mechanism comprising:

• a tractor-side PTO yoke with a unidirectional propeller shaft assembly (110);

• an outer tube yoke shaft (120) joined by means of welding with a circular cap (130) therefor; said cap (130) having four locking guides (135) fitted uniformly spaced apart on the circumference thereof;

• a spring loaded locking pin (140);

• a spring loaded PTO shaft locking pin (150);

• at least one grease nipple (155) detachably fitted in a grease nipple hole;

• a plurality of hardened metal balls (160) for bearing end and inserted in a grease hole for providing a bearing support; and

• an improved rotavator cross (170) having a shear bolt side (180) thereof;

wherein said rotavator cross (170) is configured without the mounting lobe on said shear bolt side (180) thereof, said shear bolt side (180) having PTO lock-end (172) provided with a plurality of teeth thereon.

8. Slip mechanism as claimed in claim 7, wherein said hardened metal balls (160) are inserted in a groove (132) provided in said propeller shaft (110) through said grease nipple hole to provide a bearing support in said unidirectional propeller shaft (110) assembly.

9. A method for stopping the tractor by means of the slip mechanism as claimed in anyone of the claims 1 to 8, wherein said mechanism is operated to cut-off the drive by pressing the clutch and brake pedals to noiselessly preventing the power transfer from the sprayer to the tractor driveline to disable the tractor from moving forward.

10. Method as claimed in claim 9, wherein said slip mechanism with said unidirectional propeller shaft is operated to noiselessly transfer the positive power drive from the tractor PTO to the sprayer attached thereto by restricting the impeller momentum to pass from the sprayer to the tractor driveline by stopping the tractor irrespective of complete stoppage of the sprayer rotations.

Digitally Signed.

Dated: this 29th day of August 2017. SANJAY KESHARWANI
APPLICANT’S PATENT AGENT