Claims:WE CLAIM:
1. A power shuttle transmission valve assembly (10) of a vehicle, said transmission valve assembly (10) comprises a main body (20), said main body (20) configured to accommodate a plurality of valves, said plurality of valves including:
a. a direction control valve (23) configured to facilitate selection of one of the clutches (2a, 2b) to be engaged;
b. an inching valve (22);
c. a priority valve (21);
d. a mechanical aggression control valve (24), said mechanical aggression control valve (24) having at least one orifice (243) to allow flow of pressurized hydraulic fluid through said mechanical aggression control valve (24), wherein the diameter of the orifice (243) determines the rate of pressure rise on said clutches (2a, 2b); and
e. an accumulator valve (25) disposed downstream of said mechanical aggression control valve (24) and in parallel to the line of hydraulic fluid flow leading from said priority valve (21) to said inching valve (22), said accumulator valve (25) configured to receive excessive hydraulic fluid from said mechanical aggression control valve (24) and to release the received excessive hydraulic fluid back to said inching valve (22) and thereby to said clutches (2a, 2b).
2. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said mechanical aggression control valve (24) has a plurality of externally selectable orifices (243) of different diameters, for facilitating changing of the rate of pressure rise on said clutches (2a, 2b).
3. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said inching valve (22) is disposed upstream of said direction control valve (23), said priority valve (21) is disposed upstream of said inching valve (22) and said mechanical aggression control valve (24) is disposed between said priority valve (21) and said inching valve (22).
4. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said inching valve (22) is configured to enable disengagement of the clutches (2a, 2b) during gear shifting and to enable partial engagement of the clutch corresponding to the desired direction of movement to facilitate controlled slow movement of the vehicle based on depression of the clutch pedal (3) of the vehicle by the vehicle operator, by controlling flow of hydraulic fluid towards said direction control valve (23), and said priority valve (21) is configured to provide a fixed mass flow rate of hydraulic fluid through the hydraulic circuit irrespective of the input mass flow rate.
5. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said accumulator valve (25) is configured to receive excessive hydraulic fluid from said mechanical aggression control valve (24) when said inching valve (22) is closed, and to release the received excessive hydraulic fluid back to said inching valve (22) and thereby to said clutches (2a, 2b), when said inching valve (22) is opened.
6. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said mechanical aggression control valve (24) comprises a selector sleeve (241) with an outlet, a selector spool (242) disposed within said selector sleeve (241), said selector spool (242) having an inlet, said plurality of orifices (243) of different diameters configured on said selector spool (242), said plurality of orifices (243) configured to be aligned with said outlet on said selector sleeve (241).
7. The power shuttle transmission valve assembly (10) as claimed in claim 6, wherein said selector spool (242) has a selector knob (244) configured to allow manipulation of said selector spool (242) for aligning an orifice of said plurality of orifices (243) with said outlet.
8. The power shuttle transmission valve assembly (10) as claimed in claim 6, wherein said selector spool (242) is configured to be displaced from one orifice aligning position to another by a spring-loaded detent mechanism (245).
9. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said accumulator valve (25) comprises a cavity closed by a piston (251), said piston (251) is configured to receive hydraulic fluid, said piston (251) presses against at least one spring, said spring is configured to be compressed due to displacement of said piston (251) due to the incoming hydraulic fluid.
10. The power shuttle transmission valve assembly (10) as claimed in claim 1, wherein said valve assembly (10) comprises an adapter plate (32) interfacing between said main body (20) and the transmission casing of the vehicle, said adapter plate (32) having a plurality of ports and a plurality of galleries.

Dated this 12th day of November 2019

MOHAN DEWAN, IN/PA - 25
OF R. K. DEWAN & CO.
APPLICANT’S PATENT ATTORNEY

TO,
THE CONTROLLER OF PATENTS,
THE PATENT OFFICE
AT CHENNAI
, Description:FIELD
The present disclosure relates to the field of power shuttle transmission systems of vehicles like tractors.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
A power shuttle mechanism is a mechanism actuated by a power shuttle lever available in the cabin of a vehicle such as a tractor, which makes the vehicle stop and reverse the direction of motion and move in the same speed. The power shuttle mechanism does not require a clutch to be operated. Hence, the name ‘power shuttle’. The power shuttle mechanism is driven by a hydraulic circuit comprising a plurality of valves. In a forward/reverse mode, pressure is built in the hydraulic circuit due to flow of hydraulic fluid to the wet clutches. The actuation of the wet clutches is controlled by the power shuttle transmission valve assembly. A conventional power shuttle transmission valve assembly consists of a priority valve, a modulation valve, a relief valve, a directional control valve and a proportional inching valve. The priority valve allows a fixed mass flow rate of hydraulic fluid through the hydraulic circuit irrespective of the input mass flow rate and provides the rest of the fluid to flow for lubrication of the clutches. The modulation-cum-relief valve allows modulation of time required for clutch engagement by setting a maximum pressure. The direction control valve allows selection of the clutch based on the operator’s input. The proportional inching valve disengages the clutch during gear shifting and also controls slow movement (i.e., inching) of the vehicle.
A conventional mechanical power shuttle transmission valve assembly has a single modulation time. The modulation time of the power shuttle transmission valve assembly, when optimized for providing the required pressure modulation during forward/reverse operation while the clutch is fully engaged, does not provide the required rate of increase in momentum while performing gear shifting operations which require disengaging and engaging the clutch.
When the modulation time is reduced for improving the shifting response, forward/reverse (F/R) shuttling is compromised in the form of increase in jerkiness. The operator’s expectation is to get a very minimum jerk during the operation of F/R shuttling, as the F/R shuttling is the most frequent operation performed in a vehicle with a power shuttle transmission.
Moreover, for various models of tractors, i.e., different tractors with different mass, different speed ranges, different location of the centre of gravity and so on, the same construction of a power shuttle transmission valve assembly cannot be implemented. Hence, for every model, a different power shuttle transmission valve assembly needs to be designed.
Therefore, there is felt a need to provide a power shuttle transmission valve assembly of a vehicle for mitigating the aforesaid drawbacks.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide a power shuttle transmission valve assembly for a vehicle, which has reduced response time during gear shifting.
Another object of the present disclosure is to provide a power shuttle transmission valve assembly for a vehicle, which provides a jerk-free F/R shuttling operation.
Yet another object of the present disclosure is to provide a power shuttle transmission valve assembly for a vehicle, which can be implemented across various models of the vehicle.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a power shuttle transmission valve assembly of a vehicle. The transmission valve assembly comprising comprises a main body configured to accommodate a plurality of valves. The plurality of valves includes a direction control valve, an inching valve, a priority valve, a mechanical aggression control valve and an accumulator valve. The direction control valve is configured to facilitate selection of one of the clutches to be engaged. The mechanical aggression control valve has at least one orifice to allow flow of pressurized hydraulic fluid through the mechanical aggression control valve. The diameter of the orifice determines the rate of pressure rise on the clutches. The accumulator valve is disposed downstream of the mechanical aggression control valve and in parallel to the line of hydraulic fluid flow leading from the priority valve to the inching valve. The accumulator valve is configured to receive excessive hydraulic fluid from the mechanical aggression control valve and to release the received excessive hydraulic fluid back to the inching valve and thereby to the clutches.
According to a preferred embodiment of the present disclosure, the mechanical aggression control valve has a plurality of externally selectable orifices of different diameters, for facilitating changing of the rate of pressure rise on the clutches.
According to an embodiment, the inching valve is disposed upstream of the direction control valve, the priority valve is disposed upstream of the inching valve and the mechanical aggression control valve is disposed between the priority valve and the inching valve.
The inching valve is configured to enable disengagement of the clutches during gear shifting and to enable partial engagement of the clutch corresponding to the desired direction of movement to facilitate controlled slow movement of the vehicle based on depression of the clutch pedal of the vehicle by the vehicle operator, by controlling flow of hydraulic fluid towards said direction control valve. The priority valve is configured to provide a fixed mass flow rate of hydraulic fluid through the hydraulic circuit irrespective of the input mass flow rate.
Preferably, the accumulator valve is configured to receive excessive hydraulic fluid from the mechanical aggression control valve when the inching valve is closed, and to release the received excessive hydraulic fluid back to the inching valve and thereby to the clutches, when the inching valve is opened.
In an embodiment, the mechanical aggression control valve comprises a selector sleeve with an outlet and a selector spool disposed within the selector sleeve. The selector spool has an inlet. The plurality of orifices of different diameters is configured on the selector spool. The orifices of the plurality of orifices are configured to be aligned with the outlet on the selector sleeve. In an embodiment, the selector spool has a selector knob configured to allow manipulation of the selector spool for aligning an orifice of the plurality of orifices with the outlet. Preferably, the selector spool is configured to be displaced from one orifice aligning position to another by a spring-loaded detent mechanism.
In an embodiment, the accumulator valve comprises a cavity closed by a piston, wherein the piston is configured to receive hydraulic fluid. The piston presses against at least one spring. The spring is configured to be compressed due to displacement of the piston due to the incoming hydraulic fluid.
In an embodiment, the valve assembly comprises an adapter plate interfacing between the main body and the transmission casing of the vehicle. The adapter plate has a plurality of ports and a plurality of galleries.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A power shuttle transmission valve assembly of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a plot of pressure rise versus time in the system of prior art;
Figure 2 illustrates a schematic circuit diagram of a hydraulic circuit comprising the power shuttle transmission valve assembly of the present disclosure;
Figure 3 illustrates an isometric view of the power shuttle transmission valve assembly of the present disclosure;
Figure 4 illustrates an exploded view of the power shuttle transmission valve assembly of Figure 3;
Figure 5 illustrates a sectional view of the isometric view of the power shuttle transmission valve assembly of Figure 3;
Figure 6 illustrates another sectional view of the isometric view of the power shuttle transmission valve assembly of Figure 3;
Figure 7 illustrates yet another sectional view of the isometric view of the power shuttle transmission valve assembly of Figure 3;
Figure 8 illustrates a sectional view of a mechanical aggression control valve of the power shuttle transmission valve assembly of Figure 3;
Figure 9 illustrates a sectional view of an accumulator valve of the power shuttle transmission valve assembly of Figure 3;
Figure 10 illustrates a side view of an adapter plate of the power shuttle transmission valve assembly of Figure 3;
Figure 11 illustrates another side view of the adapter plate of Figure 10; and
Figure 12 illustrates a sectional view of the adapter plate of Figure 10; and
Figure 13 illustrates a plot of pressure rise versus time in the system of the present disclosure.
LIST OF REFERENCE NUMERALS
2a forward clutch
2b reverse clutch
3 clutch pedal
10 power shuttle transmission valve assembly
20 main body
21 priority valve
22 inching valve
23 direction control valve
24 mechanical aggression control valve
241 selector sleeve
242 selector spool
243 orifices
244 selector knob
245 detent mechanism
2451 detent
2452 detent spring
2453 detent ball
2454 detent plug
25 accumulator valve
251 main piston
252 outer spring
253 inner spring
254 auxiliary piston
255 series spring
26 hydraulic fluid relief valve
27 lubricant relief valve
28 check valve
29 lubricant reservoir
30 hydraulic pump
31 hydraulic fluid reservoir
32 adapter plate
321 forward port
322 reverse port
323 input port
324 lubrication port
325 hydraulic reservoir port
326 mounting hole
327, 328, 329 galleries in the adapter plate
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises”, “comprising”, “including” and “having” are open-ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.
When an element is referred to as being “mounted on”, “engaged to”, “connected to” or “coupled to” another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed elements.
Terms such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.
A conventional power shuttle transmission valve assembly, comprises a modulation valve provides modulation time as depicted by the plot ‘a’ of the modulation time achieved, as shown in Figure 1. Different pressure modulation time periods are desired during forward/reverse shuttling operation and during clutch pedal operation for clutch engagement/disengagement during gear shifting. The piston of the modulation valve of a conventional power shuttle transmission valve assembly has a single orifice for allowing flow of pressurized fluid therethrough. The present disclosure seeks to provide a valve assembly which allows selection of different modulation times for different operations, i.e., forward/reverse shuttling and clutch pedal operation during gear shifting.
The power shuttle transmission valve assembly of a vehicle, of the present disclosure, is illustrated by the schematic diagram of Figure 2, the isometric view of Figure 3, the exploded view of Figure 4 and the various sectional views of Figure 5, Figure 6 and Figure 7. A forward clutch 2a and a reverse clutch 2b are configured to be engaged for propelling the vehicle in a forward direction and in a reverse direction respectively, and to be disengaged during gear shifting. The clutches 2a, 2b are actuated by a hydraulic circuit comprising a hydraulic fluid reservoir 31, a hydraulic pump 30 and the power shuttle transmission valve assembly for controlling the magnitude and the direction of the pressure delivered to the clutches 2a, 2b. The power shuttle transmission valve assembly comprises a main body having a plurality of ports and a plurality of galleries and is configured to accommodate a plurality of valves. The plurality of valves includes a priority valve 21, an inching valve 22, a direction control valve 23, a mechanical aggression control valve 24, an accumulator valve 25, a hydraulic fluid relief valve 26 and a check valve 28. The pressurized hydraulic fluid from the hydraulic pump 30 enters into the priority valve 21, then into the mechanical aggression control valve 24 downstream of the priority valve 21, after which the pressurized hydraulic fluid enters into the check valve 28, and then into the inching valve 22 and finally into the direction control valve 23 downstream of the inching valve 22. The accumulator valve 25 is disposed downstream of the mechanical aggression control valve 24, specifically in parallel to the line of hydraulic fluid flow leading from the priority valve 12 to the inching valve 22. The priority valve 21 is configured to drain into the hydraulic fluid into the lubricant reservoir 29 and the inching valve 22, the direction control valve 23, the mechanical aggression control valve 24, the accumulator valve 25, the hydraulic fluid relief valve 26 and the check valve 28 are configured to drain the hydraulic fluid into the hydraulic fluid reservoir 31.
The priority valve 21 is configured to receive pumped hydraulic fluid from the hydraulic pump 30 and to allow a fixed flow rate of hydraulic fluid through the hydraulic circuit irrespective of the input flow rate and is further configured to provide the rest of the fluid to flow for lubrication of the clutches 2a, 2b. The inching valve 22 is configured to enable disengagement of the clutches 2a, 2b during gear shifting and also facilitate control slow movement of the vehicle by partially engaging the clutch corresponding to the desired direction of movement. The direction control valve 23 is configured to facilitate selection of one of the wet clutches 2a, 2b to be engaged based on operator’s input. The mechanical aggression control valve 24 has at least one orifice through which the pressurized hydraulic fluid entering the mechanical aggression control valve 24 passes. The diameter of the orifice determines the rate of pressure rise on the clutches 2a, 2b, and thereby the degree of aggression exhibited by the vehicle while the clutch is engaged. The accumulator valve 25 is configured to receive excessive hydraulic fluid coming from the mechanical aggression control valve 24 and to release the received excessive hydraulic fluid back to the inching valve 22 and thereby to the clutches 2a, 2b. The hydraulic fluid relief valve 26 facilitates relieving of hydraulic back pressure exerted on the mechanical aggression control valve 24. The lubricant relief valve 27 facilitates relieving of lubricant back pressure exerted on the priority valve 21.
According to an aspect of the present disclosure, the mechanical aggression control valve 24 has a plurality of externally selectable orifices 243 of different diameters for transferring hydraulic fluid through the mechanical aggression control valve 24, for changing the rate of pressure rise on the clutches 2a, 2b. In an embodiment illustrated in Figure 8, the mechanical aggression control valve 24 comprises a selector sleeve 241 with an outlet (not shown in Figures) and a selector spool 242 disposed within the selector sleeve 241. The selector spool 242 has an inlet and the plurality of orifices 243 of different diameters are configured to be aligned with the outlet on the selector sleeve 241. In an embodiment, the selector spool 242 has four orifices 243 of different diameters. The selector spool 242 has a selector knob 244 configured to allow manipulation of the selector spool 242 for aligning one of the plurality of orifices 243 with the outlet. The selector spool 242 is configured to be displaced only from one orifice-aligning position to another by incorporating a spring-loaded detent mechanism 245. In an embodiment, the detent mechanism 245 comprises a plurality of detents 2451 provided on the selector spool 242 corresponding to the positions of the orifices 243, a detent spring 2452 and a detent ball 2453 configured to engage with the detents 2451. The detent spring 2452 and the detent ball 2453 are held against the selector sleeve 241 and the selector spool 242 by means of a detent plug 2454.
According to an embodiment of the present disclosure, the accumulator valve 25 comprises a cavity closed by a piston. The piston is configured to receive hydraulic fluid through an inlet. The piston presses against at least one spring. The spring is configured to be compressed due to displacement of the piston due to the incoming hydraulic fluid. In an embodiment as illustrated in Figure 9, the accumulator valve 25 comprises a main piston 251 pressing against an outer spring 252 and an inner spring 253. The outer spring 252 and the inner spring 253 in turn press against an auxiliary piston 254 at different steps formed on the auxiliary piston 254. The auxiliary piston presses against a series spring 255. The spring constants and the compressed lengths of the springs 252, 254, 255 are different. The accumulator valve 25 directs pressure in the hydraulic circuit to rise as per the resistance provided by the springs 252, 254, 255. The three springs 252, 254, 255 are configured to provide a suitable pressure rise curve.
The power shuttle transmission valve assembly further comprises an adapter plate 32 disposed between the main body 20 and the transmission casing (not shown) of the vehicle. The adapter plate 32 has a face on the side of the transmission valve assembly 10, shown in Figure 10, and a face on the side of the main body 20. The adapter plate 32 has a plurality of ports and a plurality of galleries, shown in Figure 11. The various ports formed on the adapter plate 32 include a forward port 321 communicating with the forward clutch 2a, a reverse port 322 communicating with the reverse clutch 2b, an input port 323 communicating with the hydraulic pump 30, a lubrication port 324 communicating with the lubricant reservoir 29 and a hydraulic reservoir port 325 communicating with the hydraulic fluid reservoir 31. The adapter plate 32 has mounting holes 326 provided on suitable points. The plurality of galleries formed in the adapter plate 32, as shown in Figure 12, include galleries 327 for connecting the input hydraulic fluid from the input port 323 to the various valves, a gallery 328 for connecting the forward port 321 with the forward clutch 2a, a gallery (not shown) for connecting the reverse port 322 with the reverse clutch 2b and galleries 329 for connecting the ports leading to the reservoir tanks in the valves.
In the working of a preferred embodiment of the power shuttle transmission valve assembly of the present disclosure, the vehicle’s operator performs forward/reverse shuttling by shifting the direction control valve 23 in a forward/reverse position, in order to supply pressurized hydraulic fluid to forward clutch 2a/ reverse clutch 2b. The accumulator valve 25 remains in a ‘non-accumulated’ OR ‘uncharged’ state because all of the pressurized fluid from the priority valve 21 is delivered through the inching valve 22 to the direction control valve 23. A relatively longer modulation time of the clutches 10a, 10b is available in this configuration, which is represented by the curve ‘b’, as illustrated in the plot of Figure 13. The hydraulic circuit provides a relatively slower response and hence a jerk-free forward/reverse shuttling operation.
During inching operation, the operator partially depresses the clutch pedal of the vehicle, to cause the inching valve 22 to remain partially open. The pressure of the hydraulic fluid delivered through the inching valve 22 and the direction control valve 23 to the selected clutch follows the predetermined modulation curve, corresponding to the selected orifice 243 in the mechanical aggression control valve 24. Surplus fluid not entering the partially open inching valve 22 enters the accumulator valve 25 to change its state to a ‘partially accumulated’ OR ‘partially charged’ state. While the clutch pedal is released during the inching operation, pressure of the hydraulic fluid delivered to the selected clutch rises smoothly due to the discharging of the accumulator valve 25. This results in a more reliable inching operation or, in other words, a very good response by the clutch pedal, which helps in activities such as hooking of implements to the vehicle (e.g., a tractor).
While performing a gear shifting operation, the vehicle operator depresses the clutch pedal completely to cause the inching valve 22 to be toggled in to a closed state, thereby preventing any fluid to be delivered. The pressurized hydraulic fluid from the priority valve 21 now enters into the accumulator valve 25 which attains an ‘accumulated’ OR ‘charged’ state. At the same time, the clutches 2a, 2b drain any hydraulic fluid collected therein through the direction control valve into the hydraulic fluid reservoir 31. The moment the clutch pedal is released after performing the shifting operation, for engaging one of the clutches 2a, 2b, the inching valve 22 opens for fluid delivery to the direction control valve 23. The hydraulic fluid accumulated in the accumulator valve 25 rushes through the inching valve 22 into the selected clutch from the clutches 2a, 2b. As a result, the selected clutch gets quickly filled. Thus, the hydraulic circuit provides a shorter modulation time during shifting operation, which is represented by the curve ‘c’ of Figure 13. Thus, the power shuttle transmission valve assembly of the present disclosure provides a quick response for clutch operation during gear shifting. In other words, there is no undesirable lag between clutch pedal release and vehicle movement. The torque transfer from the powertrain to the wheels remains nearly constant. Hence, the hydraulic circuit improves satisfaction of the operator. Moreover, it is assured that no roll back occurs during gear shifting along a rising slope.
The various applications for which the mechanical aggression control valve 24 is manipulated for changing the orifice in operation, and thereby changing the pressure modulation curve, include field operation, haulage operation, loader application etc. Also, a mechanical aggression control valve 24 with orifices of diameters suitable for various models of tractors can be implemented across the different models, with a different orifice brought in operation for a different model. The different models of tractors can have different mass, different speed ranges, different location of the centre of gravity and so on.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a power shuttle transmission valve assembly for a vehicle, which:
• provides a jerk-free forward/reverse shuttling operation;
• provides more reliable inching operation or, in other words, a very good response by the clutch pedal, which helps in activities such as hooking of implements to the vehicle;
• ensures that no roll back occurs during gear shifting along a rising slope; and
• provides an improved overall satisfaction of the operator.
The foregoing 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.
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 foregoing description of the specific embodiments 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 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.
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, but not the exclusion of any other element, integer or step, or group of elements.
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 materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context 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.
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 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.