Description:MECHANICAL DETACHABLE REAR HITCH SYSTEM FOR AGRICULTURAL TRACTORS

FIELD OF INVENTION
[0001] The present invention relates to a mechanical hitch system for agricultural Tractors. In particular, the present invention relates to a hitch system having an additional mechanical control arrangement mounted at rear end of tractor for adjusting the height of lower links from ground level. Further, the subject matter of the present patent of addition application under section 54 is modification of the granted patent application (1343/MUM/2015) filed on 31/03/2015.

BACKGROUND OF THE INVENTION
[0002] In the existing configurations of three-point linkage mechanism of agricultural tractors, the operator brings the rear end of the tractor in front of the implement for hitching (Figure 2). The operator needs to move a number of times from his seat to the rear end to adjust the lower link height by using the conventional control levers placed near the driver seat for hitching the agricultural implements (Figure 1).
[0003] Another way to do this task requires at least two persons, one to control the height of the lower link by using a position lever from driver seat and another to hitch the implement to the tractor while standing at rear end of tractor. This phenomenon was observed at actual field operation and it was confirmed that while hitching an implement to the tractor, the operator had to move several times from the tractor seat to its rear end and vice versa for adjusting the height of the lower-link to hitch the implement (Figure 2).
[0004] The available solution to the problem is a tractor with electro-hydraulic hitch system. A pair of push button switch is mounted on rear end of tractor mud guard to lift or lower the lower links and align with the implement to be attached. Study of the available technology revealed several limitations: for example, the system is costly, the servicing is complex and most importantly, it can be used only with an electronic controlled hitch control valve and moreover, the technology cannot be retrofitted on an existing set-up.
[0005] Further, there are many disadvantages while carrying out hitching of the agricultural implements by using conventional control levers normally provided near the driver seat on agricultural tractors to operate three point linkage mechanism. These are discussed in the following:
• The conventional hitching systems for agricultural tractors involve undesirable operator movements
• Often, another person is required to assist the tractor operator while hitching an agricultural implement.
• Conventional hitching systems require higher manpower and cause wastage of time and energy.
• Using the conventional hitching system leads to wastage of operator’s efforts by repeated to-and-fro movement of the operator to align tractor lift position with respect to implement to be hitched.
• In the conventional hitching system, sometimes it is very difficult for a single operator to attach heavy implements.
[0006] Therefore, it is necessary to save such undesirable operator movements and to save the wasteful efforts and time of the operator and his attendant by obviating the disadvantages associated with the conventional hitching systems.
[0007] Therefore, there is a need for a system for agricultural tractors, by which even a single operator can align and hitch the implement very easily.

OBJECTS OF THE DISCLOSURE
[0008] It is therefore the object of the present disclosure to overcome the aforementioned and other drawbacks in prior method/product/apparatus.
[0009] It is a primary object of the present disclosure to provide a wedge to avoid bending of a rear operating lever.
[0010] It is another object of the present disclosure to provide a more reliable and robust design, increasing the overall durability and longevity of the system.
[0011] It is another object of the present disclosure to provide an easily operable mechanical hitching system for agricultural tractors.
[0012] It is another object of the present disclosure to provide a mechanical hitching system for agricultural tractors, which significantly reduces frequent movements by the tractor operator.
[0013] Still another object of the present disclosure is to provide a mechanical hitching system for agricultural tractors, which can be operated single handedly by the tractor operator.
[0014] Yet another object of the present disclosure is to provide a mechanical hitching system for agricultural tractors, which saves tractor operator’s time.
[0015] It is another object of the present disclosure to provide a mechanical hitching system for agricultural tractors, which is configured as an easy hitch system.
[0016] A still further object of the present invention is to provide a mechanical hitching system for agricultural tractors, which is easy for the operator in the field for lifting of lower links.
[0017] A yet further object of the present invention is to provide a mechanical hitching system for agricultural tractors, which restricts and optimizes the operating range of rear position lever.
[0018] A yet further object of the present invention is to provide a mechanical hitching system for agricultural tractors, which does not cause discomfort/hindrance to the co-passenger sitting on mudguard/fender.
[0019] A yet further object of the present invention is to provide a cost effective solution that reduces workloads, leading to improved operational efficiency.
[0020] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.

SUMMARY
[0021] Solution to one or more drawbacks of existing technology and additional advantages are provided through the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
[0022] The present disclosure offers a solution in the form of a mechanical detachable rear hitch system for an agricultural tractor comprises a rear operating lever having a wedge provided on a peripheral surface of said rear operating lever, a tie rod configured with a tie rod pin mounted on a side facing a position lever, wherein said wedge is configured to link said rear operating lever and said tie rod by means of a tie-rod pin.
[0023] In an aspect of the invention, the rear operating lever has a hinge-point hub provided at a rear end of the rear operating lever.
[0024] In an another aspect of the invention, the rear operating lever is linked via the tie rod to the position lever by means of the tie-rod pin for engaging the tie rod thereto or disengaging said tie-rod therefrom.
[0025] In an another aspect of the invention, the position lever is brought at its lower-most position (L) and the rear operating lever is brought in the extended position thereof (Fig.3) for hitching a big agricultural implement to the tractor.
[0026] In an aspect of the invention, an idler plate hanger is provided with a hole for detaching the end of the tie-rod pin from hydraulic control sector and to engage into the hole of the idler plate hanger.
[0027] In another aspect of the invention, the wedge is provided in a middle of distal ends of the rear operating lever.
[0028] In an another aspect of the invention, the operating range of movement of said rear operating position lever is restricted and optimized in the range of 35 to 90°, preferably 65° to avoid any discomfort and/or hindrance to co-passenger sitting on the mud guard or fender of said tractor.
[0029] In an another aspect of the invention, the range of movement of the rear operating lever is restricted and optimized to lift lower links at the height ranging from 250 to 600 mm from ground, preferably 450 mm, by considering the hitching height of said implement from the ground.
[0030] In an aspect of the invention, the wedge has a hole to insert the tie rod pin provided at a distal end of the tie rod.
[0031] In an aspect of the invention, a mounting bracket is connected to the rear operating lever to a brake housing.
[0032] In an aspect of the invention, a hydraulic control sector is operated by said position lever with a grip and rotatable about a control lever axis.
[0033] In an aspect of the invention, an idler plate hanger is provided with a hole.
[0034] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS
[0035] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the present disclosure may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0036] Figure 1 shows a tractor operator controlling the position lever after bringing the tractor’s rear end in front of the agricultural implement to be hitched thereto in a conventional manner.
[0037] Figure 2 shows the tractor operator manually adjusting or positioning the height of lower links for hitching the implement in a conventional manner.
[0038] Figure 3 shows a side view of the easy hitch linkage configured in accordance with the present invention, for mechanically making lower link height or hitch point adjustment from the rear end of the tractor.
[0039] Figure 4 shows a rear view of the easy hitch linkage arrangement configured in accordance with the present invention, for mechanically making lower link height or hitch point adjustment from the rear end of the tractor.
[0040] Figure 5 shows the easy hitch arrangement configured in accordance with the present invention, with the Position Lever at lower position and rear operating lever in the extended condition thereof.
[0041] Figure 6 shows the easy hitch arrangement configured in accordance with the present invention, with the position Lever is at up position with rear operating lever is in its extended condition.
[0042] Figure 7 shows the detailed perspective view of the easy hitch arrangement configured in accordance with the present invention, with the detachable linkage for linking the rear operating lever via tie rod to the idler hanger plate in accordance with the present invention.
[0043] Figure 8 shows the detailed perspective view of the wedge located on the rear operating lever in accordance with the present invention.
[0044] The figures depict embodiments of the present subject matter for illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION
[0045] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0046] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0047] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0048] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0049] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
[0050] Hereinafter, a description of an embodiment with several components in communication with each other does not imply that all such components are required. On the contrary, a variety of optional components are described to illustrate the wide variety of possible embodiments of the present disclosure.
[0051] A possible method for solving the problem faced by the existing mechanical hitching system for agricultural tractors is by providing a mechanism to adjust the height of the lower link from the rear end of the tractor. In the mechanical hitching system for agricultural tractors accordance with the present invention, (called as easy hitch system) the lower link height is adjusted by moving a hydraulic position lever.
[0052] Figures 3 and 8 shows the right hand side view of the easy hitch arrangement configured in accordance with the present invention for an agricultural tractor, particularly illustrating a rear operating lever (100) for mechanically adjusting the lowerlink height or hitch point from the rear end (4) of the tractor (Tr). The rear operating lever (100) has a triangular shaped wedge (301) pivotably provided on a peripheral surface of said rear operating lever (100). The wedge (301) having a hole is provided in a middle of distal ends of the rear operating lever (100).
[0053] A tie rod (106) with tie rod pins (106a, 106b), a mounting bracket (108), a brake housing (110), a hydraulic control sector (112) and a position lever (114) having a grip (114a), an extended plate (114b) and control lever axis (118) are also seen here. The wedge (301 as provided in Fig. 7) is configured to link the rear operating lever (100) and the tie rod (106) by means of a tie-rod pin (106b). The hole on the wedge (301) has the vicinity to house the tie rod pin (106b) and link a distal end of the tie rod (106) with the rear operating lever (100). This design helps to avoid bending of the rear operating lever (100).
[0054] The operating range of movement of the rear operating position lever (100) is restricted and optimized in the range of 35 to 90°, preferably 65° to avoid any discomfort and/or hindrance to co-passenger sitting on the mud guard or fender of said tractor. Further, the range of movement of said rear operating lever (100) is restricted and optimized to lift lower links at the height ranging from 250 to 600 mm from ground, preferably 450 mm, by considering the hitching height of said implement (6) from the ground.
[0055] Figure 4 shows a detailed enlarged view from the driver’s seat of the rear operating lever (100). Here, the rear operating lever (100) is linked to the position lever (114) of the hydraulic control sector (112) by means of a tie-rod (106). The tie rod pin (106a) can be engaged into hole provided in idler plate hanger (120). The mounting bracket (108) is connected to the brake housing (110) at one end and to the rear operating lever (100) to which the rod (106) is also connected at the other end thereof, are also clearly visible.
[0056] Figure 5 shows the position lever (114) at its lower-most position L with the rear operating lever (100). This position is used, when a big implement (6) needs to be hitched. Since the space between the tractor and the implement (6) is less in this case, the operator needs to lock the rear operating lever (100) at its most extended position (seen here).
[0057] Figure 6 shows the position lever (114) now at its higher-most position H with the rear operating lever (100) to facilitate easy hitching of the implement (6). While shifting the rear operating lever (100) from low position (100a) shown in Figure 6 to the high position (100b), the position lever (114) travels all across the control sector (112). Accordingly, this leads to lower link movement for adjusting its height by means of the link pin height or hitch height of the implement (6) for hitching the implement to the tractor.
[0058] Figure 7 shows the detailed view of the detachable linkage configured in accordance with the present invention for linking the rear operating lever (100) via tie rod (106) to the position lever (114). Accordingly, when the easy hitch mechanism is active, the tie-rod (106) is connected to the rear operating lever (100) and an extended plate (114b) of position lever (114). This extended plate (114b) is a part of the position lever (114) of the control sector (112) and is provided to crank. Whenever, the tractor operator wants to detach this easy hitch mechanism, the tie-rod pin (106a) needs to be detached from hole (114c) of the extended plate (114b) of the position lever (114) and pinned into hole (126) of the idler plate hanger (120). This action disengages the rear operating lever (100) from the position lever (114), and it remains independent and inactive.

TECHNICAL ADVANTAGES
[0059] The mechanical easy hitch mechanism in accordance with the present invention has the following advantages:
• Actuating rear end lever for lifting and lowering lower link.
• Detachable linkage for this mechanism for idle condition.
• Cost-effective due to usage of a single rear operating lever.
• Linkage configuration to restrict operating range of rear position lever.
• No expensive electronic circuitry / toggle switch is required.
• No frequent movement of the operator to the rear end of the tractor to attach or detach the agricultural implement.
• No assistance needed for the operator to hitch the desired agricultural implement.
• Offers ease of operation and optimized to lift lower links for raising the rear position lever.
• Offers restricted and optimized operating range of rear position lever for achieving full height of lower link for hitching of implement.
• Facilitates a controlled rear lever movement to prevent any discomfort or hindrance to the co-passenger sitting on mudguard/fender.
[0060] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation, no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to disclosures containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. Also, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general, such construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances, where a convention analogous to “at least one of A, B, or C, etc.” is used, in general, such construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
[0061] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present disclosure contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the disclosure, and other dimensions or geometries are possible. Also, while a feature of the present disclosure may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present disclosure. The present disclosure also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.

LIST OF REFERENCE NUMERALS
Operator Op
Tractor Tr
Position lever 2
Tractor rear end 4
Agricultural implement 6
Rear operating lever 100
Extended position of the rear operating lever 100a
Collapsed position of the rear operating lever 100b
Tie rod 106
Tie rod pin 106a
Tie rod pin 106b
Mounting bracket 108
Brake housing 110
Hydraulic control sector 112
Position lever 114
Position lever grip 114a
Position lever extended plate 114b
Control lever axis 118
Idler plate hanger 120
Hole in idler plate hanger 126
Wedge 301
, Claims:We claim:
1. A mechanical detachable rear hitch system for an agricultural tractor, said rear hitch system comprises:
a rear operating lever (100) having a wedge (301) provided on a peripheral surface of said rear operating lever (100); and
a tie rod (106) configured with a tie rod pin (106a) mounted on a side facing a position lever (114), wherein said wedge (301) is configured to link said rear operating lever (100) and said tie rod (106) by means of a tie-rod pin (106b).
2. The mechanical detachable rear hitch system as claimed in claim 1, wherein said rear operating lever (100) comprises a hinge-point hub (103) configured with a nestled doled configuration, provided at a rear end of said rear operating lever (100).
3. The mechanical detachable rear hitch system as claimed in claim 1, wherein said rear operating lever (100) is linked via said tie rod (106) to said position lever by means of said tie-rod pin (106a) for engaging said tie rod (106a) thereto or disengaging said tie-rod (106) therefrom.
4. The mechanical detachable rear hitch system as claimed in claim 1, wherein said position lever (114) is brought at its lower-most position (L) and said rear operating lever (100) is brought in the extended position thereof (Fig.3) for hitching a big agricultural implement to said tractor
5. The mechanical detachable rear hitch system as claimed in claim 1, wherein an idler plate hanger (120) is provided with a hole (126) for detaching the end of said tie-rod pin (106a) from hydraulic control sector (112) and to engage into said hole (126) of said idler plate hanger (120).
6. The mechanical detachable rear hitch system as claimed in claims 1, wherein said wedge (301) is attached in a middle of distal ends of said rear operating lever (100).
7. The mechanical detachable rear hitch system as claimed in claims 1 to 7, wherein the operating range of movement of said rear operating position lever (100) is restricted and optimized in the range of 35 to 90°, preferably 65° to avoid any discomfort and/or hindrance to co-passenger sitting on the mud guard or fender of said tractor.
8. The mechanical detachable rear hitch system as claimed in claims 1 to 7, wherein the range of movement of said rear operating lever (100) is restricted and optimized to lift lower links at the height ranging from 250 to 600 mm from ground, preferably 450 mm, by considering the hitching height of said implement (6) from the ground.
9. The mechanical detachable rear hitch system as claimed in claims 1 to 9, wherein said wedge (301) has a hole to insert said tie rod pin (106b) provided at a distal end of said tie rod (106).
10. The mechanical detachable rear hitch system as claimed in claim 1, wherein a mounting bracket (108) is connected to said rear operating lever (100) to a brake housing (110).
11. The mechanical detachable rear hitch system as claimed in claim 1, wherein a hydraulic control sector (112) is operated by said position lever (114) with a grip (114a) and rotatable about a control lever axis (118).
12. The mechanical detachable rear hitch system as claimed in claim 1, wherein an idler plate hanger (120) is provided with a hole (126).