DESC:FIELD OF INVENTION

The present invention relates to the split-housing power take-off unit in light commercial vehicles (LCVs). In particular, the present invention relates to an indexable split-housing power take-off (PTO) unit for a rear-engine, rear-wheel drive LCV with its engine mounted in an East-West configuration. More particularly, the present invention relates to an indexable split-housing PTO unit for LCVs, which can be mounted in multiple positions according to the different PTO applications.

BACKGROUND OF THE INVENTION

The power take-off or power take-off (PTO) is one of the methods used for taking power from a power source, such as a gear box, and transmitting it to an application such as an attached implement or separate machines.

Normally, the PTO system comprises splined output shaft on a tractor or truck, which is configured for easily connecting and disconnecting the PTO-shaft and the corresponding input shaft to or from the end of any such attached implement or separate machine. In particular, light commercial vehicles are deployed for different types of applications. These applications require the power to be applied in different directions.

However, the existing PTO units offer only fixed position of the PTO or these are required to be completely removed from the transaxle and to be indexed at any angle with respect to the input shaft axis thereof. So, these PTOs do not offer any flexibility of transmitting power at different angles without removing the complete PTO assembly.

DISADVANTAGES WITH THE PRIOR ART

The problem with the existing power take-off units is that these are configured for specific purposes.
Even if the PTO is indexed about gearbox input shaft axis, the complete PTO assembly needs to be removed from transaxle adaptor plate / transaxle housing and to be attached again at a different desired position.

Therefore, there is a need for a PTO unit, in which the Power Takeoff unit axis can be changed by rotating the rear housing of PTO unit and by keeping the front housing fixed to the rear housing of PTO unit.

DEFINITIONS

Front-wheel-drive or Front-engine Front-drive (FF) layouts are the ones in which the front wheels of the vehicle are driven. This layout is typically chosen for its compactness. Since the engine and the driven wheels are disposed on the same side of the vehicle, there is no need for a central tunnel through the passenger compartment to accommodate a propeller shaft running between the engine and the driven wheels. The weight of the engine mounted over the front driven wheels also improves vehicle road-grip in normal conditions. However, in this FF layout, due to weight transference under acceleration, the weight on the front wheels is reduced and thus their traction is also reduced, thereby limiting the torque that can be utilized. The FF layout also restricts the size of the engine that can be placed in modern engine compartments, as FF configurations usually have Inline-4 and V6 engines, while longer engines such as Inline-6 and 90° V8 engines will rarely fit therein.

A transverse engine or "east-west" configuration is commonly used in such FF layouts, which is in contrast to FR layouts using longitudinal engine.

Rear-wheel drive (RWD) typically places the engine in the front of the vehicle and the driven wheels are located at the rear, a configuration known as front-engine, rear-wheel drive layout (FR layout). Most of rear-wheel-drive vehicles use a longitudinally mounted engine in the front of the vehicle, driving the rear wheels via a driveshaft linked via a differential between the rear axles.
In the present invention, the vehicle is of a Rear-Engine Rear-Wheel drive configuration, in which the rear wheels are driven by an engine placed just in front of them, i.e. behind the passenger compartment.

In contrast to the rear-engine RR layout, the center of mass of the engine is in front of the rear axle. This layout is typically chosen for its low moment of inertia and relatively favorable weight distribution (the heaviest component is near the center of the car, making the main component of its moment of inertia relatively low). The layout has a tendency toward being heavier in the rear than the front, to allow for best balance to be achieved under braking.

DESCRIPTION OF THE PRESENT INVENTION

The present invention relates to a Split-housing Power Take-off (PTO) unit for the Transaxle of East-West configuration for a Rear-Engine Rear-Wheel vehicle, which is driven by the input shaft of the gearbox. Here, the PTO-unit has two housing portions. The input shaft and its input bevel gear is enclosed in Front housing portion of the PTO. The output shaft and its output bevel gear is enclosed in Rear housing portion of the PTO. The output of the PTO-unit is at 900 to the axis of the crankshaft. PTO-unit takes the drive from the input shaft of the gearbox. PTO-unit is operable during the stationary condition of the vehicle as well while in motion. The PTO-unit in accordance with the present invention is configured as an add-on unit to the gearbox, the output of which can be indexed at any angle. The PTO-unit also includes a selector mode lever for disengaging PTO-unit from the transmission gearbox. In particular, the present invention relates to a split housing Power Takeoff Unit that can be indexed in multiple positions based on various desired applications of the Light commercial vehicle. This layout consists of two housing portions, one portion is fixed and has input bevel gear and the other housing portion is a rotatable and indexable with respect to the input shaft axis in multiple angles in different bolting configurations for various applications of the PTO unit. The Power takeoff unit in accordance with the present invention comprises a set of bevel gears, wherein the output of the PTO is disposed at 900 to the crankshaft axis.
The unique feature of this PTO configuration is that it can be rotated all around, i.e. 3600 about its input shaft axis. Therefore, this PTO can be indexed at any angle (in steps of 450) based on the desired light commercial vehicle. This PTO takes power from the input shaft of the gearbox. The rotation is made possible by rotating the Rear housing with respect to front housing. The angle is fixed by the bolting pattern of rear housing of PTO and front housing of PTO unit.

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 PTO for an East-West configuration rear-engine, rear-wheel drive transaxle of an LCV.

A further object of the present invention is to provide a multipurpose Power take-off (PTO) unit for rear-engine, rear-wheel drive transaxle of an LCV.

Still another object of the present invention is to provide a Power take-off (PTO) unit, which generates power at constant rpm.

Yet another object of the present invention is to provide a Power take-off (PTO) unit drawing output from the input shaft of the transmission gear box.

Still further object of the present invention is to provide a multipurpose Power take-off (PTO) unit, in which the output can be indexed at any angle with respect to the crankshaft axis.

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 power take-off unit (PTO) indexable in multiple positions for a detachable split-housing PTO, wherein the PTO comprises:

• a gearbox side flange with a plurality of holes for fastening the PTO on the gearbox;

• a PTO side flange also with a plurality of holes for fastening thereof to the gearbox side flange;

• a split-housing PTO consisting of a fixed rear housing portion and a rotatable front housing portion both provided with same number of holes;

wherein the rotatable front housing portion is indexable with respect to the fixed rear housing portion by aligning the holes thereof in a predefined orientation for tightening the same to each other in a predefined orientation.

Typically, the fixed rear housing portion and the rotatable front housing portion comprise eight equally spaced holes each.

Typically, the rotatable front housing portion is indexable with respect to the fixed rear housing portion in multiples of 450 angle.

Typically, a companion flange is provided on the rotatable front housing portion for attachment thereof to the implement/separate machine disposed at different orientations.

Typically, the rotatable front housing portion and fixed rear housing portion are configured as a detachable cartridge.

In accordance with the present invention, there is also provided a method of operating an indexable power take-off unit as claimed in anyone of the claims 1 to 5, wherein the method comprises the following method steps:
• Taking mechanical input from the transaxle gearbox mounted at 900 with respect to the input shaft axis;

• Taking power input from the Rear-engine Rear-wheel drive input shaft of the transaxle positioned in East-west configuration; and

• Indexing the rotatable front-housing portion with respect to the fixed rear-housing portion attached to the transaxle of the gearbox for indexing at any angle around the input shaft axis, preferably in multiples of 450.

Typically, the rotatable front housing portion is detached along with the internal components to be fitted on the fixed rear housing portion at any transaxle for matching the PTU configuration.

Typically, the power input is detached from the input shaft to the PTO unit by means of a shift system.

Typically, the indexing angle is varied, preferably in multiples of 450, by using different bolt patterns in the fixed rear housing portion and rotatable front housing portion of the PTO unit.

Typically, the output gear is changed by keeping the same input gear and by changing the orientation of the rotatable front-housing portion and the components thereof, preferably in multiples of 450.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention is briefly described with reference to the accompanying drawings (Figs. 1- 4 courtesy Wikipedia), which include:

Figure 1 shows a split housing Power Take-off (PTO) Unit fitted on a gearbox at an angular position from input shaft axis. It shows a rear-engine rear-wheel driven transaxle in east-west configuration mounted with a split-housing PTO configured in accordance with the present invention.
Figure 2 shows a split housing Power Take-off (PTO) Unit indexed with respect to the input shaft axis by 90 degree.

Figure 3 shows a PTO side of a split housing Power Take-off (PTO) Unit of Figure 1 for assembly to a gearbox on its transaxle side. It shows a cross-sectional view of PTO side of a split housing Power Take-off (PTO) unit of Fig. 1 for assembled to a gearbox on transaxle side

Figure 4a to 4d show the index able split housing Power Take-off (PTO) Unit of Figs. 3-4 for fixing on the gearbox in different orientation only by rotating the rear housing of the PTO with respect to the input shaft axis in a step of 90 degrees.

Figure 5 shows a perspective view from the other side of an indexable Power Take-off (PTO) Unit configured in accordance with the present invention. It shows an enlarged perspective view of a split housing Power Take-off (PTO) Unit configured in accordance with the present invention.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, different embodiments of the present invention are 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 indexable Power Take-off (PTO) Unit 200 configured in accordance with the present invention. This PTO unit 200 includes a rotatable housing portion 210 fixed on a fixed housing portion 220 by means of a plurality of mounting bolts 230. The fixed housing portion 220 is directly mounted on the gearbox by means of another plurality of suitable mounting bolts 240.

Figure 2 shows the Power Take-off (PTO) Unit 200 of Figure 1 indexed to another angular position with respect to the input shaft axis, i.e. after rotating by 900 with respect to the bolt positions shown in Figure 1. It should be noted that the angular positions of the PTO can be adjusted at any angle, preferably in steps of 450.

Figure 3 shows a split housing PTO side of a Power Take-off (PTO) Unit 200 of Figure 1 for assembly to a gearbox on its transaxle side 250. The PTO side includes PTO rotatable front housing 210, PTO fixed rear housing 220, companion flange 214, snap rings 212, 216, output bevel gear 222 and output shaft 224, DGBB bearing 228, support for deep-groove ball bearing (DGBB) 230, integrated input bevel gear 232, support shaft 234, C-clip locking ring 236, PTO sleeve 238, actuator sleeve 242, actuator lever 244, lock nut 246 and oil seal 248 and the transaxle side 250 includes transaxle housing 252 and extended input shaft 254.

Figure 4a shows the indexable split housing Power Take-off (PTO) Unit 200 of Figs. 1 for fixing on the gearbox in different orientation only by rotating the rotatable portion 210 of the PTO housing with respect to the input shaft axis. According to the present invention, the housing is configured in two portions, i.e. a fixed portion 220 to be fitted on the gearbox (not shown) and a rotatable portion 210 to be fixed to this fixed portion 220 of the PTO housing by fastening the mounting bolts 230 through a plurality of holes 225, for obtaining the first orientation of the PTO housing with respect to the input shaft axis.

Figure 4b shows the indexable split housing Power Take-off (PTO) Unit of Fig. 4a fixed on the gearbox in the second orientation by rotating the rotatable portion 210 of the PTO housing by 900 anti-clockwise about the input shaft axis with respect to the position shown in Figure 4a.

Figure 4c shows the indexable split housing Power Take-off (PTO) Unit of Fig.4a fixed on the gearbox in second orientation by rotating the rotatable portion 210 of the PTO housing by 1800 anti-clockwise about the input shaft axis with respect to the position shown in Figure 4a.

Figure 4d shows the indexable split housing Power Take-off (PTO) Unit of Fig. 4a fixed on the gearbox in second orientation by rotating the rotatable portion 210 of the PTO housing by 2700 anti-clockwise about the input shaft axis with respect to the position shown in Figure 4a.

Figure 5 shows a perspective view from one side of an indexable split housing Power Take-off (PTO) 200 configured in accordance with the present invention. It includes a fixed rear portion 220 of the housing having a gearbox side flange 2102 with a plurality of bolts 205 fastened through respective holes for mounting on a gearbox (not shown) and a PTO side flange 2104 which are connected to each other by a profiled wall 2106. The PTO side flange includes at least eight (8) holes 225 (not visible) and abuts PTO rear housing 220 also having a similar flange with another plurality of holes 215 (also not visible) for fixing the rotatable front housing portion 210 of the PTO housing on the fixed portion 210 of the PTO housing. These eight holes 215 facilitate the PTO front housing portion 210 to be rotated in increments of 450 at each step, thereby allowing it to be mounted in eight (8) different orientations with respect to the input shaft axis. If a particular degree is required, it can be put such that the bolting pattern is also changed. Hence, we can vary the different output directions of the PTO through the companion flange 214.

WORKING OF THE INVENTION

The PTO unit in accordance with the invention can be operated as under:

• PTO takes mechanical input from transaxle gearbox, which is mounted at 900 with respect to the input shaft axis.

• Taking power input from Rear-engine Rear-wheel drive input shaft of the transaxle positioned in East-west configuration.

• Allowing the rotatable front-housing with respect to the fixed rear-housing attached to the transaxle of the gearbox for indexing at any angle around the input shaft axis, preferably in 450 increments.
• Detaching the front housing along with the internal components to be fitted on to rear housing at any transaxle for matching the PTU configuration.

• Detaching the power input from the input shaft to the PTO unit by means of a shift system, preferably a mechanical, electrical, hydraulic or pneumatic shift system.

• Varying the indexing angle by using different bolt patterns in two fixed rear and rotatable front housing portions of the PTO unit.

• Facilitating to change the output gear by keeping the same input gear, just by changing the rotatable front-housing and the components thereof and vice-versa.

• Working of these two housing portions as a detachable cartridge.

TECHNICAL & ECONOMIC ADVANTAGES OF THE INVENTION

The PTO Unit configured in accordance with the present invention has the following advantages:

- The indexing capability of PTO can be achieved by rotating one housing of PTO instead of removing the full housing from transaxle which helps in avoiding contamination of transaxle parts.

- Ease of operation of indexing with respect to a single housing PTO.

- Oil leakage during indexing is avoided with this new indexing procedure.

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.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. 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.

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 and 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. 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 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 power take-off unit (PTO) indexable in multiple positions for a detachable split-housing PTO, wherein the PTO comprises:

• a gearbox side flange with a plurality of holes for fastening the PTO on the gearbox;

• a PTO side flange also with a plurality of holes for fastening thereof to the gearbox side flange;

• a split-housing PTO consisting of a fixed rear housing portion and a rotatable front housing portion both provided with same number of holes;

wherein the rotatable front housing portion is indexable with respect to the fixed rear housing portion by aligning the holes thereof in a predefined orientation for tightening the same to each other in a predefined orientation.

2. Power take-off unit as claimed in claim 1, wherein the fixed rear housing portion and the rotatable front housing portion comprise eight equally spaced holes each.

3. Power take-off unit as claimed in claim 1, wherein the rotatable front housing portion is indexable with respect to the fixed rear housing portion in multiples of 450 angle.

4. Power take-off unit as claimed in claim 1, wherein a companion flange is provided on the rotatable front housing portion for attachment thereof to the implement/separate machine disposed at different orientations.

5. Power take-off unit as claimed in claim 1, wherein the rotatable front housing portion and fixed rear housing portion are configured as a detachable cartridge.
6. A method of operating an indexable power take-off unit as claimed in anyone of the claims 1 to 5, wherein the method comprises the following method steps:

• Taking mechanical input from the transaxle gearbox mounted at 900 with respect to the input shaft axis;

• Taking power input from the Rear-engine Rear-wheel drive input shaft of the transaxle positioned in East-west configuration; and

• Indexing the rotatable front-housing portion with respect to the fixed rear-housing portion attached to the transaxle of the gearbox for indexing at any angle around the input shaft axis, preferably in multiples of 450.

7. Method as claimed in claim 6, wherein the rotatable front housing portion is detached along with the internal components to be fitted on the fixed rear housing portion at any transaxle for matching the PTU configuration.

8. Method as claimed in claim 6, wherein the power input is detached from the input shaft to the PTO unit by means of a shift system.

9. Method as claimed in claim 6, wherein the indexing angle is varied, preferably in multiples of 450, by using different bolt patterns in the fixed rear housing portion and rotatable front housing portion of the PTO unit.

10. Method as claimed in claim 6, wherein the output gear is changed by keeping the same input gear and by changing the orientation of the rotatable front-housing portion and the components thereof, preferably in multiples of 450.

Dated: this 30th day of April 2016. SANJAY KESHARWANI
APPLICANT’S PATENT AGENT