Claims:We claim:

1. A tow hook height adjustment mechanism for vehicles, said tow hook height adjustment mechanism comprising:

(a) a mounting bracket (34) for mounting said tow hook height adjustment mechanism on the vehicle;

(b) a tow hook assembly (30) depended from said mounting bracket (34);

(c) tow hook height adjustment means (60) for mounting said tow hook assembly (30) to said mounting bracket (34);

wherein said height adjustment means (60) connects said tow hook assembly (30) to said mounting bracket (34) in a pivotable manner for adjusting the height of said tow hook assembly to one of multiple height selection options by means of locking and release mechanism therein.

2. A tow hook height adjustment mechanism as claimed in claim 1, wherein said mounting bracket (34) comprises:

• a pair of vertically disposed members spaced apart to accommodate there between said tow hook height adjustment means (60) connected to said tow hook assembly (30);

• said vertically disposed members having a plurality of holes for the passage of fasteners therethrough for connecting said mounting bracket to said vehicle as well as for connecting said tow hook assembly (30) to said tow hook height adjustment means (60);

wherein said vertically disposed members comprise a pair of steel plates having mutually perpendicular legs (L1, L2) having a plurality of holes (26, 28) at the top ends thereof and at least two holes at the lower end of one of the legs facing away from the vehicle and having a single hole for selective positioning of said tow hook assembly (30) at the targeted tow hook height.

3. A tow hook height adjustment mechanism as claimed in claim 1, wherein said height adjustment means (60) comprises:

(i) a pair of upper hinges (42), each of said hinges having a plurality of holes (52) therethrough disposed along the length thereof;

(ii) a pair of tow height adjustment elements or quadrants (48) disposed below said upper hinges (42), each of said elements having a plurality of holes (54) therethrough disposed along the length thereof and also having a plurality of holes (56) disposed transverse to said holes (54);

(iii) a respective fastener set (24, 44) for assembling said height adjustment means (60); and

(iv) a pair of hollow guide bushes (58) each provided to be spaced apart between said pairs of upper hinges (42) and quadrants (48);

wherein a set of locking pin (50) and R-pin (40) for securing said height adjustment means (60) at the targeted height of said tow hook assembly (30).

4. A tow hook height adjustment mechanism as claimed in claim 1, wherein said tow hook assembly (30) comprises:

- a tow hook body (35) having a substantially U-shape with a rear wall connected to the upper and lower flanges thereof horizontally disposed in parallel;

- a respective through hole made through the top and bottom corners of said tow hook body (35) at the rear end thereof;

- a respective hole made in said top and bottom flanges for inserting said tow hook therethrough;

- a tow hook pin (32) with a lever (36) protruding above the upper end thereof;

- said tow hook pin (32) having a hole at the lower end thereof, and

- a lynch pin (46) for insertion through said hole in tow hook pin (32) for securing and making said tow hook assembly (30).
5. A tow hook height adjustment mechanism as claimed in claim 3, wherein the first ends of said upper hinges (42) are connected to said mounting bracket (34) via said upper holes (28) on said leg (L2) of mounting bracket (34) and the second ends of said upper hinges (42) are connected to said tow hook assembly (30) via the upper through hole made through the top corner of said tow hook body (35).

6. A tow hook height adjustment mechanism as claimed in claim 3, wherein the first ends of said quadrants (48) are connected to said mounting bracket (34) via said lower holes (28) on said leg (L2) of mounting bracket (34) and the second ends of said quadrants (48) are connected to said tow hook assembly (30) via the lower through hole made through the lower corner of said tow hook body (35).

7. A tow hook height adjustment mechanism as claimed in claim 3, wherein said locking pin (50) comprises a head to be supported around the upper hole (28) on one leg (L1) of said mounting bracket (34) and a hole disposed at the other end thereof beyond the other leg (L2) for insertion of said R-pin (40) therein to secure said height adjustment means (60) at a targeted height of said tow hook assembly (30).

8. A tow hook height adjustment mechanism as claimed in claim 3, wherein said locking pin (50) is inserted through one of said holes (56) adjusts tow hook height to a respective height depending on the number of holes (56) made on said quadrants (48).

9. A tow hook height adjustment mechanism as claimed in claim 3, wherein said quadrant (48) is made with three numbers of said holes (56) for respectively positioning said tow hook at the first uppermost height or at the second middle or intermediate height or at the third lowermost height thereof.

10. A method of adjusting the tow hook height by means of the tow hook height adjustment mechanism as claimed in claim 9, wherein said method comprises the steps of:

(I) fixing of said mounting bracket (34) by means of a plurality of fasteners tightened on the rear end of a towing vehicle;

(II) placing said tow hook pin (32) on the vertical hole in said tow hook body (35) and locking thereof by inserting said lynch pin (46) through said hole at the lower end of tow hook pin (32) for assembling said tow hook assembly (30);

(III) assembling said upper hinges (42) and said tow height adjustment elements or quadrants (48) to said tow hook assembly (30) by inserting a respective fastener (24) through the holes provided at the upper and lower corners of said tow hook body (35);

(IV) inserting a respective fastener (24) through the middle holes (52) of said upper hinges (42) and said quadrant (48) after placing a respective guide bush (58) therebetween and tightening them together by means of a respective nut (44); and

(V) assembling the other ends of aid upper hinges (42) and quadrants (48) by inserting another respective guide bush (58) therebetween and by inserting another respective fastener (24) therethrough and tightening them together by means of a respective nut (44); and

(VI) inserting said locking pin (50) through hole (38) in leg (L1) of said mounting bracket (34), through one of the three vertically spaced apart holes (56) on said first quadrant (48), through the hole (38) in leg (L2) of said mounting bracket (34) and through the corresponding one of three vertically spaced apart holes (56) on said second quadrant (48) and by inserting said R-pin (40) through the hole in said locking pin (50) for securing said tow hook assembly (30) to obtain the corresponding tow hook height.

11. Method as claimed in claim 10, wherein said tow hook assembly (30) assembled with said quadrant (48) having three vertically spaced apart holes (56) provides following three tow height positioning options:

(A) inserting said locking pin (50) through the upper holes (56) of said quadrants (48) and locking by means of R-pin (40) provides the lowermost tow height; or

(B) inserting said locking pin (50) through the middle holes (56) of said quadrants (48) and locking by means of R-pin (40) provides the middle or intermediate tow height; or

(C) inserting said locking pin (50) through the lower holes (56) of said quadrants (48) and locking by means of R-pin (40) provides the uppermost tow height.

12. A method of adjusting the tow hook height by means of the tow hook height adjustment mechanism as claimed in claim 10, wherein said method comprises adjusting tow hook height depending on the number of holes (56) provided in said tow height adjustment elements or quadrants (48).

Digitally Signed.

Dated: this 18th day of March 2019.

(SANJAY KESHARWANI)
REGN. No. IN/PA-2043
APPLICANT’S PATENT AGENT
For: MAHINDRA & MAHINDRA LTD.
, Description:FIELD OF INVENTION

[001] The present invention relates to the technical field of agricultural tractors and trailer tow-hook assemblies. In particular, the present invention relates to the hitch mechanism for attaching the vehicle/implement to be towed by the towing vehicles such as tractors. More particularly, the present invention relates to a quick and multiple tow-hook height adjustment.

BACKGROUND OF THE INVENTION

[002] The hitch mechanism is used for attaching any towed vehicle to a towing vehicle. In agricultural tractor and trailer assemblies include rear tow hook, mounting bracket. A tow hook connects the tractor to a towed vehicle and normally installed at rear side of a tractor to provide a mechanical coupling between tractor and towed vehicle or trailer. In haulage application, a loaded trailer is towed by tractor through the tow hook attached thereto.

[003] In Indian market, almost all tractor manufacturers provide tow hook as an accessory. Currently available tow hooks in the market have facility for adjusting height in 2 or 3 stages. The height of tow hook requires adjustment as per the height, load and the number of axles of the trailer. The height adjustment elements are configured to adjust the height for about 20 inches from ground level for the coupling device.

PRIOR ART

[004] In a conventional tow hook, the height of the tow hook is adjusted by means of nuts and bolts. The tow hook height adjustment is normally done in three stages.

[005] The first stage involves removal of tow hook mounting means, the second stage involves vertical shifting of the tow hook as per the required height and the third stage involves assembling the tow hook at this height by means of the mounting hardware, such as nuts and bolts.
[006] US PATENT 8033563 B2 discloses a height adjustable hitch assembly. The present invention provides a trailer hitch assembly mountable to a receiver hitch of a vehicle. The trailer hitch assembly includes a vertically extending channel member having opposing side flanges. Each of the side flanges includes equally spaced holes. A locking member having two pins spaced from one another the same distance as the holes in the flanges secures a hitch assembly to the channel member at a desired height. The height can be quickly and easily adjusted by removing the locking member, moving the hitch assembly to the desired height and reinserting the locking member. The channel member and the dual locking pin minimize rocking, swaying and pivoting of the hitch assembly relative to the vehicle.

DISADVANTAGES WITH THE PRIOR ART

[007] The following are the disadvantages with the conventional tow hook height adjustment means discussed above:

[008] The height adjustment of tow hook to done by removing and re-assembling of mounting means such as nuts and bolts (6 to 8 sets). All three stages of the conventional tow hook height-adjustment process require about 30 minutes, which a great loss of operational duration.

[009] Moreover, the presently available tow-hook height adjustment mechanism in the market also involve a large number of parts, thus making them costly to manufacture and maintain.

OBJECTS OF THE INVENTION

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

[011] An object of the present invention is to provide a low-cost tow hook height adjustment mechanism for tractors.

[012] Another object of the present invention is to provide a tow hook height adjustment mechanism for tractors for quickly adjusting the tow hook height.

[013] Still another object of the present invention is to provide a tow hook height adjustment mechanism which can be retrofitted in the existing tractors as well as new models thereof.

[014] Yet another object of the present invention is to provide a tow hook height adjustment mechanism for use for towing in all types of off-road vehicles.

[015] Yet another object of the present invention is to provide a tow hook height adjustment mechanism which can height can be adjusted at any position.

[016] A further object of the present invention is to provide a tow hook height adjustment mechanism which involves a substantially reduced no. of parts.

[017] A still further object of the present invention is to provide a tow hook height adjustment mechanism reducing required welding to make the same.

[018] A yet further object of the present invention is to provide a tow hook height adjustment mechanism which is compatible with relevant safety standards.

[019] 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 INVENTION

[020] In accordance with the present invention, there is provided a tow hook height adjustment mechanism for vehicles, the tow hook height adjustment mechanism comprising:
a) a mounting bracket for mounting the tow hook height adjustment on a vehicle’s rear side;

b) a tow hook assembly depended from the mounting bracket;

c) tow hook height adjustment means for mounting the tow hook assembly to the mounting bracket;

wherein the height adjustment means connects the tow hook assembly to the mounting bracket in a pivotable manner for adjusting the height of the tow hook assembly to one of multiple height selection options by means of locking and release mechanism therein.

[021] Typically, the mounting bracket comprises:

• a pair of vertically disposed members spaced apart to accommodate therebetween the tow hook height adjustment means connected to the tow hook assembly;

• the vertically disposed members having a plurality of holes for the passage of fasteners therethrough for connecting the mounting bracket to the vehicle as well as for connecting the tow hook assembly to the tow hook height adjustment means;

wherein the vertically disposed members comprise a pair of steel plates having mutually perpendicular legs having a plurality of holes at the top ends thereof and at least two holes at the lower end of one of the legs facing away from the vehicle and having a single hole for selective positioning of the tow hook assembly at the targeted tow hook height.

[022] Typically, the height adjustment means comprises:

(i) a pair of upper hinges, each of the hinges having a plurality of holes therethrough disposed along the length thereof;

(ii) a pair of tow height adjustment elements or quadrants disposed below the upper hinges, each of the elements having a plurality of holes therethrough disposed along the length thereof and also having a plurality of holes disposed transverse to the holes;

(iii) a respective fastener set for assembling the height adjustment means; and

(iv) a pair of hollow guide bushes each provided to be spaced apart between the pairs of upper hinges and quadrants;

wherein a set of locking pin and R-pin for securing the height adjustment means at the targeted height of the tow hook assembly.

[023] Typically, the tow hook assembly comprises:
- a tow hook body having a substantially U-shape with a rear wall connected to the upper and lower flanges thereof horizontally disposed in parallel;

- a respective through hole made through the top and bottom corners of the tow hook body at the rear end thereof;

- a respective hole made in the top and bottom flanges for inserting the tow hook therethrough;

- a tow hook with a lever protruding above the upper end thereof;

- the tow hook having a hole at the lower end thereof, and

- a lynch pin for insertion through the hole in tow hook pin for securing and making the tow hook assembly.

[024] Typically, the first ends of the upper hinges are connected to the mounting bracket via the upper holes on the leg of mounting bracket and the second ends of the upper hinges are connected to the tow hook assembly via the upper through hole made through the top corner of the tow hook body.

[025] Typically, the first ends of the quadrants are connected to the mounting bracket via the lower holes on the leg of mounting bracket and the second ends of the quadrants are connected to the tow hook assembly via the lower through hole made through the lower corner of the tow hook body.
[026] Typically, the locking pin comprises a head to be supported around the upper hole on one leg of the mounting bracket and a hole disposed at the other end thereof beyond the other leg for insertion of the R-pin therein to secure the height adjustment means at a targeted height of the tow hook assembly.

[027] Typically, the locking pin is inserted through one of the holes adjusts tow hook height to a respective height depending on the number of holes made on the quadrants.

[028] Typically, the quadrant is made with three numbers of the holes for respectively positioning the tow hook at the first uppermost height or at the second middle or intermediate height or at the third lowermost height thereof.

[029] In accordance with the present invention, there is also provided a method of adjusting the tow hook height by means of the tow hook height adjustment mechanism as claimed in claim 9, wherein the method comprises steps of:

(I) fixing of the mounting bracket by means of a plurality of fasteners tightened on the rear end of a towing vehicle;

(II) placing the tow hook on the vertical hole in the tow hook body and locking thereof by inserting the lynch pin through the hole at the lower end of tow hook for assembling the tow hook assembly;

(III) assembling the upper hinges and the tow height adjustment elements or quadrants to the tow hook assembly by inserting a respective fastener through the holes provided at the upper and lower corners of the tow hook body;

(IV) inserting a respective fastener through the middle holes of the upper hinges and the quadrant after placing a respective guide bush therebetween and tightening them together by means of a respective nut; and

(V) assembling the other ends of aid upper hinges and quadrants by inserting another respective guide bush therebetween and by inserting another respective fastener therethrough and tightening them together by means of a respective nut; and

(VI) inserting the locking pin through hole in leg of the mounting bracket, through one of the three vertically spaced apart holes on the first quadrant, through the hole in leg of the mounting bracket and through the corresponding one of three vertically spaced apart holes on the second quadrant and by inserting the R-pin through the hole in the locking pin for securing the tow hook assembly to obtain the corresponding tow hook height.

[030] Typically, the tow hook assembly assembled with the quadrant having three vertically spaced apart holes provides following three tow height positioning options:

(A) inserting the locking pin through the upper holes of the quadrants and locking by means of R-pin provides the lowermost tow height; or

(B) inserting the locking pin through the middle holes of the quadrants and locking by means of R-pin provides the middle or intermediate tow height; or

(C) inserting the locking pin through the lower holes of the quadrants and locking by means of R-pin provides the uppermost tow height.

[031] Typically, the method comprises adjusting tow hook height depending on the number of holes provided in the tow height adjustment elements or quadrants.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[032] The present invention will be briefly described with reference to the accompanying drawings, wherein:

[033] Figure 1a shows a perspective view of the tractor mounted with tow hook height adjustment assembly at rear thereof.

[034] Figure 1b shows a side view of the trailer attached to the tractor through the tow hook height adjustment assembly of Fig. 1a.

[035] Figure 2a shows a perspective view of the conventional tow hook height adjustment assembly fitted on the tractor’s rear-axle.

[036] Figure 2b shows a side view of the first stage of height adjustment by relocating and retightening the fasteners after adjusting tow hook height in the tow hook height adjustment assembly.

[037] Figure 2c shows a side view of the second stage of height adjustment by relocating and retightening the fasteners after adjusting tow hook height in the tow hook height adjustment assembly.

[038] Figure 2d shows a side view of the third stage of height adjustment by relocating and retightening the fasteners after adjusting tow hook height.

[039] Figure 3a shows perspective view of tow hook height adjustment mechanism configured according to the present invention fitted on tractor’s rear-axle.

[040] Figure 3b shows an exploded view of a tow hook height adjustment mechanism according to the present invention for fitting on tractor’s rear end.

[041] Figure 3c shows a side view of the tow hook height adjustment mechanism in a first stage of height adjustment by locking pin and R-pin after adjusting tow hook height to the uppermost position thereof.

[042] Figure 3d shows a side view of the tow hook height adjustment mechanism in a second stage of height adjustment by locking pin and R-pin after adjusting tow hook height to a central position thereof.

[043] Figure 3e shows a side view of the tow hook height adjustment mechanism in a third stage of height adjustment by locking pin and R-pin after adjusting tow hook height to the lowermost position thereof.

[044] Figure 4a shows another exploded perspective view of the tow hook height adjustment mechanism of Fig. 3a depicted with the mounting arrangement thereof for adjusting the tow hook height by a single locking pin and R-pin.

[045] Figure 4b shows the assembly of the tow hook height adjustment mechanism of Fig. 4a in central position by the single locking pin and R-pin.

[046] Figure 5 shows a perspective view of the tow hook mounting bracket for mounting tow hook height adjustment mechanism 30 of Fig. 4a on rear axle.

[047] Figure 6 shows a tow hook height adjustment mechanism of Fig. 4b in front view, side view and top view thereof.

[048] Figure 7a shows the first adjustment of the tow hook height adjustment by using the single locking pin arrangement of Fig. 3.

[049] Figure 7b shows the second adjustment of the tow hook height adjustment by using the single locking pin arrangement of Fig. 3.

[050] Figure 7c shows the third adjustment of the tow hook height adjustment by using a single pin type locking arrangement in the mechanism of Fig. 3.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[051] In the following, the tow hook height adjustment mechanism 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.
[052] Figure 1a shows a perspective view of the tractor 02 mounted with tow hook height adjustment assembly 30 at rear thereof.

[053] Figure 1b shows a side view of the trailer 04 attached to the tractor 02 through the tow hook height adjustment assembly 30 of Fig. 1a.

[054] Figure 2a shows a perspective view of the conventional tow hook height adjustment assembly 30fitted on the tractor’s rear-axle 10, which includes a tow hook pin 32, a tow hook mounting bracket 34, a plurality of nut-bolt sets 22 and 24. Normally 6 to 8 pairs each are required for mounting the tow hook height adjustment assembly 30 at the rear end of rear axle 10.

[055] Figure 2b shows a side view of tow hook height adjustment assembly 30 mounted by means of tow hook mounting bracket 34 on the rear end of rear axle 10 by means of nut-bolts 22 and by relocating and retightening nut-bolts 24 to the uppermost position in the first height adjustment thereof.

[056] Figure 2c shows a side view of tow hook height adjustment assembly 30 mounted by means of tow hook mounting bracket 34 on the rear end of rear axle 10 by nut-bolts 22 and by relocating and retightening nut-bolts 24 to a middle/central position in second height adjustment thereof.

[057] Figure 2d shows a side view of the third stage of height adjustment assembly 30 mounted by means of tow hook mounting bracket 34 on the rear end of rear axle 10 by nut-bolts 22 and by relocating and retightening nut-bolts 24 to the lowermost position in third height adjustment thereof.

[058] Figure 3a shows a perspective view of the tow hook height adjustment mechanism configured according to the present invention and fitted on tractor’s rear-axle 10. Here also, mounting bracket 34 (Shown in Figure 3b) is tightened by a set of nut-bolt 22 in holes 26 provided therein. The tow hook assembly 30 includes tow hook pin 32 fitted on body 35 by means of lynch pin 46 thereunder. Although, tow hook assembly 30 is tightened by another set of nut-bolts 24, 44 to maintain a different tow hook height by using a single locking pin 50 having a through hole at the other end thereof (not visible here) for inserting a R-pin 40 therein for locking the tow hook assembly 30 in the desired position, to be described with reference to Fig. 3b below.

[059] Figure 3b shows an exploded view of the tow hook height adjustment mechanism according to the present invention before mounting thereof on the rear end of tractor’s rear axle 10. These bolts 24 are used for tightening tow hook assembly 30 on this mounting bracket 34 having a hole 38 for inserting the locking pin 50 and R-pin 40 is used for locking it at a height in the uppermost, middle or lowermost position. The tow hook assembly 30 is fixed between the mounting bracket 34 by means of upper hinges 42 and quadrants 48 at the upper and lower side thereof respectively. Upper hinges 42 include three holes 52 each. Similarly, quadrants 48 include three holes 54 each but also include three additional holes 56 spaced apart in a vertical plane with respect to holes 54 as shown separately in upper hinge 42 and quadrant 48 in this figure. Upper hinges 42 are pivotably mounted at the vertical member of mounting bracket 34 by means of a nut-bolt set 24, 44 passed through an upper hole 28 and by placing a guide bush 58 therebetween for guiding and avoiding lateral movement of tow hook assembly 30. Similarly, quadrants 48 are pivotably mounted at the vertical member of mounting bracket 34 by means of a nut-bolt set 24, 44 passed through a lower hole 28 and by placing a guide bush 58 therebetween for guiding and avoiding lateral movement of tow hook assembly 30. The mounting bracket 34 is also provided with an additional hole 38 facing away from the lower holes 28 on either vertical member for facilitating tow hook height adjustment in 3 different positions, i.e. uppermost position, middle position and lowermost position. Another bolt 24 each is passed through the middle hole on upper hinges 42 and quadrants 48, by placing a respective guide bush 58 therebetween and tightened by a respective nut 44. Tow hook assembly 30 includes a hole each at the upper and lower read ends thereof corresponding to holes 52 and 54 provided on the other end of upper hinges 42 and quadrants 48. Now, tow hook assembly 30 is connected between the other ends of upper hinges 42 and quadrants 48 by means of inserting a respective bolt-bot set 24, 44. This way the tow hook assembly 30 is depended from mounting bracket 34 by means of upper hinges 42 quadrants 48. Tow hook pin 32 is used for locking trailer eye bolt to tow hook. A lynch pin 46 is provided for locking of tow hook pin 32 from below tow hook assembly 30. The unique feature of the present invention underlies the provisioning of 3 holes 56 spaced apart on quadrants 48 in a vertical plane, which are used in cooperation with the hole 38 provided on the mounting bracket 34 for selectively inserting the locking pin 50 in one of these three holes 56 and by inserting R-pin 40 to secure the tow hook assembly 30 in this position. This facilitates in adjusting the tow-hook assembly 30 to position at the uppermost, muddle or lowermost position thereof by inserting locking pin 50 through hole 38, then through either of the upper, middle or lower hole 56 provided on the quadrant 48 for obtaining one of these three positions of tow hook assembly 30.

[060] Figure 3c shows a side view of the first stage of height adjustment by locking pin 50 and R-pin 40 after adjusting the height of tow hook assembly 30 to an uppermost position thereof. Here, locking pin 50 is inserted through hole 38 on mounting bracket 34 and then through lower hole 56 on the quadrant 48 and by securing the locking 50 on the other end thereof by inserting R-pin 40 in a locking hole provided therein. Thus, it raises the tow hook assembly 30 in the uppermost position thereof.

[061] Figure 3d shows a side view of the second stage of height adjustment by locking pin 50 and R-pin 40 after adjusting the height of tow hook assembly 30 to a middle position thereof. Here, locking pin 50 is inserted through hole 38 on mounting bracket 34 and then through middle hole 56 on the quadrant 48 and by securing the locking 50 on the other end thereof by inserting R-pin 40 in a locking hole provided therein. Thus, it keeps the tow hook assembly 30 in a middle position thereof.

[062] Figure 3e shows a side view of the first stage of height adjustment by locking pin 50 and R-pin 40 after adjusting the height of tow hook assembly 30 to a lowermost position thereof. Here, locking pin 50 is inserted through hole 38 on mounting bracket 34 and then through lower hole 56 on the quadrant 48 and by securing the locking 50 on the other end thereof by inserting R-pin 40 in a locking hole provided therein. Thus, it lowers the tow hook assembly 30 in a lowermost position thereof.

[063] Figure 4a shows another exploded perspective view of the tow hook height adjustment mechanism configured according to the present invention for adjusting the tow hook height by a single locking pin 50 inserted through the hole 38 on mounting bracket 34 and then through one of three holes 56 provided on quadrants 48 and then securing it in the selected position by inserting R-pin 40 to obtain one of three positions of tow hook assembly 30.

[064] Figure 4b shows the assembly of the tow hook height adjustment mechanism of Fig. 4a in central position by a locking pin 40 and R-pin 40.

[065] Figure 5 shows a perspective view of the tow hook mounting bracket for the tow hook height adjustment mechanism of Fig. 4a on tractor’s rear end. Here, three holes 26 on mounting bracket 34 are shown for tightening of bolts 22 on the rear end of tractor’s rear axle 10. Two holes 28 for tightening bolts 24 for suspending tow hook assembly 30 by means of upper hinges 42 and quadrants 48 as well as a hole 38 for inserting locking pin 50 therethrough for achieving the desired tow hook position, as explained above, is also shown.

[066] Figure 6 shows a tow hook height adjustment mechanism of Fig. 4b in central position depicted in front view, side view and top view thereof.

[067] Figure 7a shows the tow hook height adjustment in uppermost position by using the single locking pin 50 and R-pin 40 arrangement of Fig. 3c.

[068] Figure 7b shows the tow hook height adjustment in a middle position by using the single locking pin 50 and R-pin 40 arrangement of Fig. 3d.

[069] Figure 7c shows the tow hook height adjustment in a lowermost position by using a single pin type locking 50 and R-pin 40 arrangement of Fig. 3e.

[070] Therefore, simply by removing R-pin 40 from locking pin 50 and relocating locking pin 50 in one of the three holes 56 provided on quadrants 48, tow hook height adjustment can be done very quickly, i.e. just within one minute which is a substantial time saving with respect to conventional tow hook height adjustment means requiring up to 30 minutes for shifting nuts-bolts. This also reduces operator’s fatigue during such prolonged height adjustment process.

[071] Although, here for sake of simplicity of representation and for elucidation, quadrant is shown with only three holes 56, the number of holes 56 can be increased to facilitate tow hook height adjustment in more than three positions, by appropriately redesigning the quadrant 48.

[072] Thus, practically any hitch height can be adjusted by adjusting the height of tow hook assembly in any desired position in the given range of the quadrant designed therefor.

[073] This tow hook height adjustment mechanism also minimizes the rocking, swaying and pivoting of the tow hook assembly 30 relative to vehicle.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

[074] The tow hook height adjustment mechanism configured in accordance with the present invention has the following technical and economic advantages:

1) Hitch height adjustment time reduced drastically from 30 minutes to 1 minute.

2) Easy and fatigue-free height adjustment.

3) Adaptable to various desired height adjustments.

4) Modifying the quadrant design is easy for various tow hook heights.

5) Tow hook assembly is easily adjustable to accommodate different types of hitches.

6) Tow hook assembly is easily adjustable to accommodate the differences in height between different vehicle and trailer hitches

[075] The exemplary embodiments described in this specification are intended merely to provide an understanding of various manners in which this embodiment may be used and to further enable the skilled person in the relevant art to practice this invention. The description provided herein is purely by way of example and illustration.

[076] Although, the embodiments presented in this disclosure have been described in terms of its preferred embodiments, the skilled person in the art would readily recognize that these embodiments can be applied with modifications possible within the spirit and scope of the present invention as described in this specification by making innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies and assemblies, in terms of their size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

[077] While considerable emphasis has been placed on the specific features of the preferred embodiment described here, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiments without departing from the principles of the invention.

[078] These and other changes in the preferred embodiment of the invention 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 invention and not as a limitation.

[079] Many of the fastening, connection, processes and other means and components utilized in this invention are widely known and used in the field of the invention described, and their exact nature or type is not necessary for an understanding and use of the invention by a person skilled in the art and they will not therefore be discussed in significant detail.

[080] 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.

[081] 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.

[082] 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.

[083] Also, any reference herein to the terms ‘left’ or ‘right, ‘up’ or ‘down, or ‘top’ or ‘bottom’ are used as a matter of mere convenience and are determined by standing at the rear of the machine facing in its normal direction of travel.

[084] Furthermore, the various components shown or described herein for any specific application of this invention can be widely known or used in the art by persons skilled in the art and each will likewise not therefore be discussed in significant detail. When referring to the figures, like parts are numbered the same in all of the figures.