FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM
Not Applicable
BACKGROUND OF THE INVENTION
Towing dollies that function by raising an opposing pair of tires on a vehicle requiring towing have long been known in the art. Existing towing dollies are generally bulky, heavy, and require significant exertion to operate. Also, many existing towing dollies can only be used in conjunction with a tow vehicle specifically designed and outfitted for towing vehicles.
SUMMARY OF THE INVENTION
A towing dolly embodying the principles of the invention can be broken apart and easily stored in a tow vehicle when not in use. The only special requirement of the tow vehicle is that it has a standard hitch to allow attachment of a tongue on the towing dolly. An operator assembles four sides of a rectangular-shaped frame of the towing dolly on a driving surface beneath the tow vehicle, so that the four sides cradle a pair of opposing tires to be raised on a towed vehicle. In a preferred embodiment, the rectangular frame can be adjusted in size to accommodate different towed vehicles. The four corners of the rectangular frame are designed to rotatably flex in a horizontal plane, so that the entire frame flexes in parallelogram fashion when the towing dolly is pulled around a curve or turn, allowing the towed vehicle to track appropriately and safely behind the tow vehicle.
The rectangular frame cradling the opposing pair of tires on the towed vehicle is raised off of the driving surface by means of a liftable attachment between left and right side cross members of the rectangular frame and each of a pair of dolly wheel assemblies. A variety of means for lifting the rectangular frame are possible including hydraulic, screw-driven, pulley-driven, lever-and-ratchet driven, pneumatic, or any other manner of achieving sufficient mechanical advantage to raise the rectangular frame of the towing dolly and one end of the towed vehicle above a driving surface to a height sufficient to allow dolly-style towing.
These and other features of the present invention will be more readily and fully understood by reference to the accompanying illustrations and the detailed description that follows.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE ILLUSTRATIONS
The accompanying illustrations are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The illustrations depict exemplary embodiments of the present invention and together with the description serve to further explain the principles of the invention. Other aspects of the invention and the advantages of the invention will be better appreciated as they become better understood by reference to the Detailed Description when considered in conjunction with accompanying illustrations, and wherein:
FIG. 1 is perspective view of one embodiment of the collapsible towing dolly according to the present invention;
FIG. 2 is an exploded view of one embodiment of the rectangular frame and tongue assembly of the towing dolly according to the present invention;
FIG. 3 is a perspective view showing one embodiment of the attachment of the dolly wheel assemblies to the side cross members according to the present invention;
FIG. 4 is a partial side view showing the rectangular frame of the dolly in a lowered position according to one embodiment of the present invention;
FIG. 5 is a partial side view showing the rectangular frame of the dolly in a raised position according to one embodiment of the present invention;
FIG. 6 is a view from directly above of the dolly as positioned when traveling straight forward according to one embodiment of the present invention;
FIG. 6A is an enlarged view from above of the left side of the dolly (as indicated in FIG. 6) as positioned when the dolly is being towed around a curve to the right according to one embodiment of the present invention;
FIG. 7 is a close-up perspective view of a flexing joint of the dolly according to one embodiment of the present invention;
FIG. 8 is an isometric view of an alternative embodiment of the invention employing a jack to raise the dolly into towing position;
FIG. 9 is an isometric of an embodiment of the invention with an optional motorcycle towing attachment in place; and
FIG. 10 is an alternative isometric view of an embodiment of the invention with an optional motorcycle towing attachment in place.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1-3, a collapsible towing dolly, generally referred to as dolly 5, is shown for attachment between a tow vehicle (not shown) and a towed vehicle (not shown). The collapsible towing dolly 5 is comprised of a rectangular frame 10. For the purposes of this document, the terms “left,” “right,” “front,” and “rear” are to be interpreted from the perspective of an operator seated in a driver's position in the tow vehicle. The rectangular frame 10 is bounded by four sides; the four sides comprising a front cross member 11, a rear cross member 15, and a pair of side cross members 500; the four sides joined by four flexing joints (710, 720, 730, and 740). The rectangular frame 10 is sized to cradle an opposing pair of tires to be raised on the towed vehicle.
The four flexing joints including a right-front flexing joint 710, a right-rear flexing joint 720, a left-front flexing joint 730, and a left-rear flexing joint 740. The right front flexing joint 710 being a means for hinged attachment of a right end of the front cross member 12 and a first end of one of the pair of side cross members 501, allowing limited rotation of the right front flexing joint 710 in a horizontal plane. The right-rear flexing joint 720 being a means for hinged attachment of the right end of the rear cross member 16 and the second end of one of the pair of side cross members 502, allowing limited rotation of the right rear flexing joint 720 in a horizontal plane. The left front flexing joint 730 being a means for hinged attachment of the left end of the front cross member 13 and the second end of one of the pair of side cross members 502, allowing limited rotation of the left front flexing joint 730 in a horizontal plane. The left rear flexing joint 740 being a means for hinged attachment of the left end of the rear cross member 17 and the first end of one of the pair of side cross members 501, allowing limited rotation of the left rear flexing joint 740 in a horizontal plane. As shown in FIGS. 6 and 6A, the limited horizontal rotation of the four flexing joints (710, 720, 730, and 740) allows the rectangular frame 10 to flex in parallelogram fashion when the towing dolly 5 is pulled around a curve or turn by the tow vehicle, so that the towed vehicle tracks appropriately and safely behind the tow vehicle.
FIG. 7 provides a detailed view of a preferred embodiment of one of the four flexing joints (710, 720, 730, and 740). In this embodiment, a turning bracket 415, having a hollow aperture, is affixed to one of the ends of the front cross member (12 or 13) or one of the ends of the rear cross member (16 or 17). The turning bracket further includes a pair of bracket pin holes 417. The hollow aperture of the turning bracket is sized and positioned to loosely receive the first end 501 or the second end 502 of one of the pair of side cross members 500. At least one side cross member connecting pin hole 507 is positioned near the first end 501 and the second end 502 of each of the pair of side cross members 500. A turning bracket pin 401 is removably inserted through the pair of turning bracket holes 417 and one of the side cross member connecting pin holes 507, rotatably affixing one end of the pair of side cross members 500 to one end of the front cross member 11 or the rear cross member 15. A plurality of side cross member connecting pin holes 507 allows the rectangular frame 10 to be sized to cradle tires with contact patches of varying length on the towed vehicle.
In a preferred embodiment of the present invention, the front cross member 11 has as adjustable length and the rear cross member 15 has an adjustable length, which allows the dolly 5 to accommodate towed vehicles with different outside widths between the opposing pair of tires to be raised. In the embodiment shown most clearly in FIG. 2, the front cross member 11 comprises a front central cross member 200 and a pair of front outer cross members 250. The front central cross member 200 having a right end 201 and a left end 202, each end having a plurality of front cross member sizing holes 207. Each of the pair of front outer cross members 250 includes a first end 251 and a second end 252. The second end 252 is affixed to one of the four turning brackets 415 and the first end 251 has a hollow tubular structure sized to receive the right end 201 or the left end 202 of the front central cross member 200. The first end 251 further includes a pair of front cross member holes 257 aligned on opposite sides of the tubular structure. The pair of front cross member holes 257 are positioned to receive a front cross member pin 211 removably inserted through the pair of front cross member holes 257 and one of the plurality of front cross member sizing holes 207 when the right end 201 or the left end 202 of the front central cross member 200 is received within the first end 251 of one of the pair of front outer cross members 250, allowing the operator to adjust the length of the front cross member 11.
Similarly, in the embodiment shown most clearly in FIG. 2, the rear cross member 15 comprises a rear central cross member 300 and a pair of rear outer cross members 350. The rear central cross member 300 having a first end 301 and a second end 302, each end having a plurality of rear cross member sizing holes 307. Each of the pair of rear outer cross members 350 includes a first end 351 and a second end 352. The second end 352 is affixed to one of the turning brackets 415 and the first end 351 has a hollow tubular structure sized to receive the first end 301 or the second end 302 of the rear central cross member 300. The first end 301 further includes a pair of rear cross member holes aligned on opposite sides of the tubular structure. The pair of rear cross member holes 357 are positioned to receive a rear cross member pin 311 removably inserted through the pair of rear cross member holes 357 and one of the plurality of rear cross member sizing holes 307 when the first end 301 or the second end 302 of the rear central cross member 300 is received within the first end 351 of one of the pair of rear outer cross members 350, allowing the operator to adjust the length of the rear cross member 15.
As shown in FIGS. 1-3, the towing dolly also comprises a tongue assembly 100 centrally affixed to the front cross member 11. The tongue assembly 100 protrudes perpendicularly away from the front cross member toward physical communication with a hitch on the tow vehicle (not shown). The tongue assembly 100 has a front end including a ball socket 120 configured for removable attachment to the hitch.
Preferably, the front cross member 11 includes a means for removably affixing the tongue assembly 100 to the rectangular frame 10. In a preferred embodiment most clearly shown in FIG. 2, a tongue receiver 205 is centrally affixed between the right end 201 and the left end 202 of the front central cross member 200. The tongue receiver 205 protrudes perpendicularly from the length of the front cross member 11 in a direction for physical communication with a rear end 105 of the tongue assembly 100. The tongue receiver 205 has a tubular structure with a hollow interior, the hollow interior sized and shaped to receive the rear end 105 of the tongue assembly 100. The tongue assembly 100 includes a tongue hole 107 through the rear end 105. The tongue receiver 205 includes a pair of tongue receiver holes 209 aligned on opposite sides of the tubular structure. The tongue receiver holes 209 are positioned to receive a tongue pin 101 removably inserted through the aligned tongue hole 107 and the pair of tongue receiver holes 209 when the rear end 105 of the tongue assembly 100 is received within the tongue receiver 205, allowing an operator to removably affix the tongue assembly 100 to the front cross member 11.
The towing dolly 5 further comprises a pair of dolly wheel assemblies 600 each having a matching size and structure. Each dolly wheel assembly 600 includes a means for liftable attachment to one of the pair of side cross members 500 and a means for raising one of the pair of side cross members 500. After an operator has assembled the rectangular frame 10 around contact patches of the pair of opposing tires to be lifted on the towed vehicle, the operator engages the means for lifting the side cross members. After an operator has raised the opposing pair of tires on the towed vehicle, which are cradled in the rectangular frame 10 of the towing dolly 5, the operator can use the tow vehicle attached to the dolly via the tongue assembly 100 to transport the towed vehicle. One skilled in the art could devise a variety of mechanisms for liftable attachment between each of the dolly wheel assemblies 600 and each of the side cross members 500. Similarly, one skilled in the art could devise a variety of means for raising the side cross members 500, including hydraulic, screw-driven, pulley-driven, lever-and-ratchet driven, pneumatic, or any other manner of achieving sufficient mechanical advantage to raise the rectangular frame 10 of the towing dolly 5 and one end of the towed vehicle above a driving surface to a height sufficient to allow dolly-style towing.
In an embodiment shown in FIG. 3-5, the towing dolly 5 includes a pair of side cross-member pillars 550, each side cross-member pillar 550 having a matching size and structure. Each side cross-member pillar 550 is centrally affixed to one of the pair of side cross members 500, projecting perpendicularly upward from the side cross member 500. Each side cross-member pillar 550 has a hollow interior sized to receive an axle post 610 affixed to an axle 605 on one of the pair of dolly wheel assemblies 600. In the embodiment shown, one of a pair of vehicle-raising bolts 620 is used to liftably attach one of the pair of axle posts 610 to one of the pair of side cross-member pillars 550. The operator turns each vehicle-raising bolt 620 to draw each side cross-member pillar 550 upward, thus raising the rectangular frame 10 and one end of the towed vehicle to a height sufficient to allow dolly-style towing.
Each of the pair of side cross-member pillars 550 includes a first tow-position pin hole 551 and each of the pair of axle posts 610 includes a second tow-position pin hole 611. The first tow-position pin hole 551 and the second tow-position pin hole 611 are each sized to securely receive one of a pair of tow-position pins 601. The first tow-position pin hole 551 and the second tow-position pin hole 611 are brought into alignment when the operator raises the rectangular frame 10 to the height sufficient to allow dolly-style towing. The operator secures the rectangular frame 10 in a raised position by inserting each of the pair of tow position pins 601 through each of the pair of first tow-position pin holes 551 and second tow-position pin holes 611.
In an alternative embodiment shown in FIG. 8, each of a pair of jacks 650 is affixed to each of the pair of side cross-member pillars 550. The jack 650 having an extendable member 620 that protrudes downward when a jack bolt 651, or similar mechanism, is rotated by the operator. When the rectangular frame 10 is initially assembled around the opposing pair of tires to be raised on the towed vehicle, the extendable member 620 is withdrawn within the jack 650. The operator raises the rectangular frame 10 by rotating each of the pair of jack bolts 651 to cause each of the pair of extendable members 620 to protrude downward. When the rectangular frame 10 has reached a sufficient height, the operator inserts each of the pair of axle posts 610 (not shown in FIG. 8) into each of the pair of side cross-member pillars 550. The operator secures the rectangular frame 10 in a raised position by inserting each of the pair of tow-position pins 601 through each of the pair of first tow-position pin holes 551 and second tow-position pin holes 611. Before using the towing dolly 5 to tow a vehicle, the operator withdraws each of the pair of extendable members 620 within each of the pair of jacks 650 by rotating each of the pair of jack bolts 651 in an opposite direction as that required to extend the extendable members 620.
Referring now to FIGS. 9-10, one embodiment of an optional motorcycle towing attachment 800 is shown. The motorcycle towing attachment 800 is comprised of a motorcycle wheel channel 810, the motorcycle wheel channel 810 having sufficient length to support both a front wheel and a rear wheel of a motorcycle being towed. The motorcycle wheel channel is affixed to the front cross member 11 and the rear cross member 15. The motorcycle towing attachment also preferably includes a front-wheel cage 820 affixed near a front end 811 of the motorcycle wheel channel 810, the front-wheel cage 820 sized and structured to securely receive and provide lateral support for the front wheel of the motorcycle being towed. The motorcycle towing attachment 800 further includes a pair of front tie bars 815 and a pair of rear tie bars 817. One of the pair of front tie bars 815 protrudes perpendicularly away to the left from the front end 811 of the motorcycle wheel channel 810 and the other one of the pair of front tie bars 815 protrudes perpendicularly away to the right from the front end 811 of the motorcycle wheel channel 810. One of the pair of rear tie bars 817 protrudes perpendicularly away to the left from a rear end 812 of the motorcycle wheel channel 810 and the other one of the pair of rear tie bars 817 protrudes perpendicularly away to the right from the rear end 812 of the motorcycle wheel channel 810. The pair of front tie bars 815 and the pair of rear tie bars 817 provide locations for the operator to use chains, ropes, cables, or the like to secure the motorcycle being towed into position on the towing dolly 5.
While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) but that the invention will include all embodiments falling with the scope of this disclosure.
Patent Application
20160059913
