VEHICLE TOWING APPARATUS

Abstract: A vehicle towing dolly has improved mechanisms for securing a towed vehicle to the dolly. The mechanisms feature a selectively movable stop element (24) which the vehicle bumper engages, a safety ratchet (90) on a derrick-lifting mechanism (20), and triangulating tension members (26, 28, 30, 32) for connection to the vehicle. The mechanism are easy to deploy, minnimize vehicle damage, and increase safety for the towing operator. The vehicle towing dolly has an improved steering mechanism (108, 112, 114, 116, 120, 122), which advantageously damps unwanted wheel turning, and latches the wheel axle with the appropriate caster angle, depending on the direction of towing movement.

Description: VEHICLE TCWING APPARATUS BACKGROUND This invention provides improvements in vehicle towing apparatus. The improvements are particularly suited for use in a vehicle towing dolly of the type disclosed in U.S.Patent No. 4,087,008, the disclosure of which is incorporated herein by this reference. An object of this invention is to provide an improved vehicle securing mechanism for towing apparatus. A particular object is to provide dolly-like towing apparatus with a vehicle stop against which the towed vehicle is secured, and with cables, chains or like tension elements that are readily deployed and yet securely connect the vehicle to the towing apparatus. Another object of the invention is to provide vehicle towing dolly apparatus having a rotationally- elevating derrick mechanism and having a vehicle bumper-engaging stop carried on the derrick mechanism and arranged for ready deployment and for protecting the vehicle from towing damage. A further object of the invention is to provide such a towing dolly that can be hitched to a vehicle and made ready for towing, without being hitched to a towing vehicle and without other stabilizing restraint. Another object of the invention is to provide a ratcheting safety latch on a telescopic vehicle- raising derrick mechanism. It is also an object of the invention to provide a vehicle towing dolly that has ready, safe steerage control. OMPI, Further objects of the invention will in part be obvious and will in part appear hereinafter. Features of the invention may be used to advantage in various land vehicles, but they are considered of primary importance in a vehicle towing dolly and accordingly are described herein particularly with reference to that use. GENERAL DESCRIPTION The illustrated embodiment of the invention is a vehicle-towing dolly having a trailer-like chassis with a tow hitch on the forward end of a tow bar and with a pair of freely-rotating spaced-apart wheels. Each wheel is mounted with a king-pin steering system to turn about a king pin when the dolly is towed around a corner. That is, the wheels turn to follow automatically a turning towing movement imposed on the tow bar. Each king pin is angled to provide positive caster, and the axis for each wheel is rotatable to shift the caster for positive tracking in either direction automatically as the dolly is towed forward and, alternatively, in reverse. Moreover, the wheel-mounting axle stub which each king pin mounts to the axle has a wheel rotation axis that is offset vertically below the center line of the axle. This vertical offset of the wheel axis from the caster-shift axis maintains positive caster for either towing direction reliably and without unwanted shifting. A damping device between the steering track rod and the chassis damps unwanted steering movement, and stops limit the maximum steering angle. The illustrated vehicle-towing dolly further has an A-frame like derrick hinged to the chassis above O PI the axle. A winch device forward on the chassis can lift the derrick from a lowered position, where the derrick extends rearwardly, to an upright position. A flexible tension element assembled with chains, straps and the like attaches at one end to the top of the derrick for attachment at the other end, when the derrick is lowered, to the axle or another frame' member of the vehicle to be towed. With this lifting connection in place, raising the derrick lifts the attached end of the towed vehicle. A second, stabilizing tension element attaches from the first such element, preferably adjacent the attachment to the towed vehicle, to a lower end of the derrick, or alternatively to the chassis. The arrangement is such that, when viewed from the side, the two tension elements and the raised, upright derrick each form a separate side of a triangle. This hitching attachment of the towed vehicle to the towing dolly is relatively easy to put in place, and provides a secure transfer of the weight of the lifted end of the towed vehicle to the dolly wheels. Moreover, the dolly is stable in an upright position when hitched in this manner with a towed vehicle, with one end of the towed vehicle off the ground, without vertical restraint on the hitch of the towing dolly. Moreover, a stabilizer foot can be deployed, from a nested, collapsed, towing position to an extended position, to stabilize the towing dolly for lifting a vehicle to the towing condition without other restraint on the dolly. Further in accord with the invention, the vehicle-towing dolly carries a stop member adjacent the top of the derrick and which the bumper or a like struc¬ tural element of the towed vehicle abuts when secured to the dolly. This abutment of the towed vehicle with the dolly enhances the firm security of the hitching connection and enhances the upright stability of the dolly when carrying a towed vehicle. The stop member is mounted to face rearwardly—and hence abut the towed vehicle—for all positions of the derrick between the lowered, vehicle attaching position and the raised, upright, vehicle towing position. Another feature of the stop member is that it relatively freely moves vertically as the bumper or other stop engaging member of the towed vehicle vertically moves relative to the top of the derrick as the winch-driven derrick lifts the vehicle. This relative vertical movement of the stop member accommodates a relative movement of the towed vehicle and thereby avoids damage that otherwise occurs to a towed vehicle. In the illustrated embodiment of the invention, a telescoping guide rod hingedly mounted to the derrick and to the forward towing end of the dolly chassis carries the stop member to provide the desired rearward facing orientation of the stop member. An automatic safety lock on the telescoping arm-like rod prevents unwanted rod extension for enhancing safety for the operator during the lifting of a towed vehicle onto the dolly and while attaching lower holding chains. The invention accordingly comprises the features of construction, combinations of elements, and arrangements of parts exemplified in the constructions hereinafter set forth, and the scope of the invention is indicated in the claims. OMPI sAs. IPO ^RNAΎ\ For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description and the accompanying drawings, in which: FIGURE 1 shows a vehicle-towing dolly embodying features of the invention; FIGURES 2 and 3 are simplified side elevation views of the dolly of FIGURE 1 arranged respectively for initial connection with a towed vehicle and with the towed vehicle lifted thereon ready for towing; FIGURE 4 is a fragmentary side elevation view of the stop member elements of the towing dolly of FIGURE 1; FIGURE 5 is a view similar to FIGURE 4 with the stop member in a raised position relative to that in FIGURE 4; FIGURE 6 is a top plan view of the stop member elements as seen along line 6-6 in FIGURE 4; FIGURE 7 is a fragmentary view of the axle bar and track rod of the dolly of FIGURE 1 showing the releasable steering lock; FIGURE 8 is a fragmentary view of the telescopic derrick-lifting guide of the dolly of FIGURE 1 showing a ratcheting safety-lock; FIGURE 9 shows a detail of one end of the axle of the dolly of FIGURE 1 with a vertically-offset wheel OMPI ^ y -fi ¬ stem secured thereto by means of an angled king pin arrangement; and FIGURES 10 and 11 are fragmentary simplified showings of the dolly of FIGURE 1 with an extendable, stabilizing foot. DESCRIPTION OF ILLUSTRATED EMBODIMENT FIGURE 1 shows a vehicle towing dolly 10 according to the invention constructed with a trailer-like chassis indicated generally at 12 which mounts a tow hitch 14 at the forward end and a pair of steerable wheels 16, 18 at the back end. A derrick assembly, indicated generally at 20, is hingedly mounted at the base thereof to the chassis 12 above the wheel axle 22. The derrick assembly carries a stop mechanism, indicated generally at 24, for abutment against the bumper of a vehicle that is to be towed, as appears in FIGURES 2 and 3. A pair of tensile lifting elements 26 and 28, shown in FIGURES 2 and 3, attach to the top of the derrick assembly, and a pair of stabilizing tensile elements 30 and 32 attach to a base section of the derrick assembly. The tensile elements 26, 28, 30 and 32 are arranged for combined attachment to the towed vehicle, indicated generally at 34, as appears in FIGURES 2 and 3. A winch 36 on the dolly 10 is mounted to the chassis 12 adjacent the forward end for controlling the lowering of the derrick assembly from the upright position shown in FIGURE 1 to the lowered, vehicle-attaching, position shown in FIGURE 2, and for lifting the derrick assembly with the towed vehicle to the upright, vehicle-towing position of FIGURE 3. With further reference to FIGURE 1, the illustrated chassis 12 is assembled with a transverse OMPI axle bar 38 connected between two brace bars 40 and 42 in a triangular configuration that mounts a pair of tow- positioning hitch plates 44a and 44b. A tongue bar 46 is secured to the positioning plates and mounts the hitch 14 at the front end. The tongue bar is slidable relative to the hitch plates between a projecting, forward position shown in FIGURE 2 and a retracted, reverse position shown in FIGURE 3. Stops on the tongue bar limit this sliding movement. The hitch plates 44a and 44b allow the tow bar 46 and hitch 14 to be selectively positioned vertically relative to the tow dolly 10 to orient the dolly chassis 12 essentially horizontal, as appears in FIGURE 2, when the hitch 14 is connected with a towing vehicle (not shown). With further reference to FIGURES 1, 2 and 3, the illustrated derrick assembly 20 employs a pair of A-frame bars 48, 50, each hingedly mounted at its lower end to the axle bar 38, and joined together at the upper end by a pair of tow bar-mounting plates 51a, 51b. A tow bar 52 is seated between the plates and pinned to them at its mid-point for mounting to the top of the derrick assembly 20 in fixed position relative to the A-frame bars except for freedom to rotate about the axis of the mounting pin 54. A telescoping derrick guide employs a sleeve 56 pinned to the top of the hitch plates 44a and 44b and telescopically supporting a guide rod 58 that projects rearwardly beyond the top of the derrick assembly 20, to which it is pinned as described below with reference to FIGURE 6. The dolly winch 36 is mounted on the telescopic guide sleeve 56 and the winch cable engages the top of the derrick assembly, as shown in FIGURES 2 and 3. With this construction of the derrick assembly 20 and the telescopic guide and the winch, the derrick assembly can rotate downward to the rear about an axis parallel to the vehicle axle and with the guide rod 58 telescopically moving within the sleeve 56 to extend rearwardly therefrom and with the winch cable extended, all as appears in FIGURE 2. The operation of the winch raises the derrick assembly from this lowered position to the upright position shown in FIGURES 1 and 3, during which the guide rod 58 telescopically slides forward relative to the guide sleeve 56. FIGURES 4, 5 and 6 show the extension of the guide rod 58 rearwardly beyond the derrick assembly 20 for mounting the stop mechanism 24. The illustrated stop mechanism employs a pair of upper parallel arms 60 and a pair of lower parallel arms 62; one end of each arm is pinned to the rearward end of the guide rod 58. The pin 64 which affixes the upper parallel arms to the guide rod 58 also fastens the guide rod to the upper end of the derrick assembly 20. The other end of each parallel arm is pinned to a rearwardly-facing stop plate 66. The stop plate carries on its rear face a cushioning resilient stop block 70. A pair of coil tension springs 72, 72 is connected between the outer pin 74 of the upper parallel arm 60 and the inner pin 76 of the lower parallel arms 62 for resiliently biasing the stop plate and stop block downwardly against a laterally projecting tab 77 to a lower position shown in FIGURE 4. In this normal position, the parallel arms 60 and 62 are aligned with the longitudinal guide rod 58 and the stop plate is spaced by a gap 78 from the outer end of the guide bar 58. This mounting and biasing of the stop plate and stop block allow the plate and block to be moved vertically upward relative to the end of the guide rod 58, and correspondingly relative to the derrick assembly, until the space 78 is diminished and the stop plate 66 seats against the end of the guide ' rod 58, as appears in FIGURE 5. This movement of the stop block 70, from the normal, relatively lowered position of FIGURE 4 to the raised position shown in FIGURE 5, elongates and thereby tensions the springs 72. In addition to the tension of the springs 72 thus urging the stop mechanism downward to the normal position shown in FIGURE 4, the illustrated mechanism includes a shelf-like plate 80 carried adjacent the top of the derrick assembly and extending rearwardly to engage and bear against the upper parallel arms 60 when the derrick is in the lowered position of FIGURES 2 and 4. In other positions of the derrick assembly 20, the plate 80 is out of engagement with the parallel arms 60 when the stop assembly is in the normal position. Thus when the derrick assembly is upright, the stop mechanism is free to move to the tensioned raised position of FIGURE 5 without interference by the plate 80. With this deployment of the stop block 70, it moves with the derrick assembly 20 but faces rearwardly with only a slight change in angle for all positions of the derrick assembly between the lowered loading position shown in FIGURE 2, and the upright towing position of FIGURE 3. Further, the stop block 70 is essentially free, other than from the restraint of the tension spring 72, to move upwardly along the derrick assembly as it is engaged by the bumper 82 or other forward structural elements of the towed vehicle 34 during the lifting of the towed vehicle. . OMPI The stop mechanism provides a solid and secure abutting engagement of the towed vehicle with the vehicle-towed dolly when the vehicle is fully lifted onto the dolly and ready for towing. This occurs with the illustrated embodiment, as illustrated in FIGURES 3 and 5, by the movement of the stop block 70 to collapse the space 78 so that the mechanism 24 provides a solid engagement bewteen the vehicle bumper 82 and the dolly derrick assembly 20. With reference again to FIGURES 2 and 3, the illustrated tow dolly 10 employs two lifting tensile elements 26 and 28, one connected at either end of the tow bar 52 to either side of the towed vehicle 34. The tensile element 26, typically identical to the other element 28, has a chain section 26a for adjustable attachment to a hook 52a on the tow bar, a belt section 26b that feeds under and bears against the bumper 82 and other structural elements at the front bottom of the vehicle 34, and a chain section 26c that terminates with a hook 26d or like anchorage for removable and replaceable attachment to the axle or other frame element of the towed vehicle. The chain sections are preferred for flexibility and ease of link-by-link adjustment, and the central belt section is preferred to engage the towed vehicle with minimal marring or other damage. There preferably also are two identical stabilizing tensile elements 30 and 32, each connecting between a side of the dolly and either the towed vehicle or the attachment thereto of a lifting element 26, 28. The illustrated stabilizing tensile element 30, preferably identical to the element 32, has a chain section 30a affixed at one end to the element 26 to be carried therewith; the illustrated connection is at the connection of the chain section 26c with the belt section 26b. At the other end of the stabilizing chain section 30a a hook enables removable and replaceable connection to the tensile element 26, illustratively at the connection to the hook 26d. The tensile element 30 connects to the derrick assembly 20 adjacent the lower base portion. In the illustrated dolly, this connection includes a rigid stabilizer arm 30b hinged to the lower end of the A-frame bar 48 and having at its outer end an adjustable hook and/or slot connection to the chain section 30a, as shown in FIGURE 3. The dolly 10 also includes a belt 84 for suspending the stabilizer arm 30b from one side of the tow bar 52. A like stabilizer arm 32b is hinged to the other A-frame arm 50 and a like belt 86 is connected between the outer end of that stabilizer bar and the other side of the tow bar. The stabilizer arms 30b and 32b, although considered preferable, can be omitted, and each chain section 30a and 32a connected directly to the lower part of the derrick assembly 20 above the pivot connection of the derrick assembly to the frame. In operation, after the dolly is aligned with the end of the vehicle to be towed and the derrick assembly placed in the lowered position, each, lifting tensile element 26 and 28 is connected, with minimal slack, from the tow bar 52 at the outer end of the derrick assembly to the vehicle to be towed. The winch is operated to lift the derrick assembly upright and thereby lift the end of the vehicle and draw it upward against the dolly at the stop block 70. Each stabilizing tensile element 30, 32 is then connected at IPO one end between the juncture of the vehicle and the lifting element 26, 28, respectively, and at the other end to the dolly derrick assembly. On the illustrated dolly, this connection is made by way of the optional stabilizing arms 30b and 32b, respectively. The connection is adjusted for minimal slack, see FIGURE 3. The winch is then operated in reverse to slacken the winch cable and thereby transfer the vehicle weight to both sets of tensile elements 26, 28 and 30, 32. When the dolly and the towed vehicle are viewed from the side at this juncture, as appears in FIGURE 3 which corresponds to a projection in a vertical plane, the'A-frame bar 48, the lifting tensile element 26, and the stabilizing tensile element 30 each form different sides of a triangular arrangement. Each tensile element 26 and 30 is in tension, whereas the A-frame bar 48 is in compression. This configuration of the towed vehicle and the towing dolly, with the towed vehicle securely abutting the stop block 70, provides a firm, secure and stable connection between the vehicle and the dolly for lifting, holding and towing. Moreover, the dolly is stable with this connection in the orientation shown in FIGURE 3, even without vertical constraint on the tow hitch 14. That is, the towing dolly with the derrick assembly upright and fully connected with a towed vehicle is stable on the two wheels 16 and 18 in the orientation shown in FIGURE 3. FIGURE 8 shows a ratcheting safety latch 90, also shown in FIGURES 1, 2 and 3, mounted on the telescope sleeve 56 and selectively engageable with the guide rod 58 to prevent unwanted rearward movement of the guide rod. The latch thus prevents unwanted or accidental lowering of the derrick assembly 20. The illustrated latch 90 has an arm 92 projecting rearward from a hinged mounting to the sleeve 56 to bear against the upper surface of the guide rod 58. The underside of the arm carries a pawl 94 having a camming rear surface and a latching front surface. The upper wall of the guide rod 58, against which the arm 92 applies the pawl 94, is apertured or otherwise recessed with a succession of pawl-receiving holes 96. The guide rod 58 is free to telescopically move forward (to the left in FIGURE 8) relative to the sleeve 56 inasmuch as the camming surface of the pawl 94 allows each latching hole 96 to pass thereby with minimal interference. However, upon rearward movement of the guide rod 58 within the telescope sleeve, the stop surface of the pawl engages the side of a hole 96 to block further such movement. The latch arm 92 has a manually engageable handle extension 98 with which the dolly operator can lift the arm 92 and thereby remove the pawl 94 from engagement with the guide rod hole, thereby to release the guide rod for rearward movement, i.e. extension, from the telescopic sleeve 56. FIGURE 9 shows that the illustrated vehicle towing dolly 10 mounts the spindle 100 of each wheel 16, 18 with the axial center line thereof vertically spaced by a distance 102 below the center line of the axle 22. This vertical offset retards accidental shifting of the wheel caster orientation from the proper position. More particularly, the axle 22, rotatable within the axle bar 38, has an upwardly-angled end stem 104 on each end. Each wheel spindle 100 has a correspondingly downwardly-angled bifurcated socket 106 that seats on OMPI one end stem. A king pin 108 fastens the spindle socket to the axle stem at each end of the axle 22. Each king pin 108 is oriented at an angle from the vertical (when viewed from the dolly front or back) by virtue of the angled orientation of the axle stem and spindle socket. Rotation of the axle 22 in the clockwise direction (FIGURE 2) accordingly rotates both king pins to provide a positive caster angle for forward movement of the dolly 10. Conversely, rotation of the axle counterclockwise, as shown in FIGURE 3, shifts each king pin orientation to provide positive caster for reverse movement of the dolly. (FIGURES 2 and 3, for clarity of illustration, diagrammatically show the king pin 108.) The vertical offset 102 provides a bias force to urge the axle 22 to maintain either rotational position, rather than shift therefrom except when the towing force on the trailer hitch 14 actually changes direction. In the illustrated dolly, the angle of the king pin 108 from the vertical in FIGURE 9 is nine degrees, the rotation of the axle 22 between the two positions shown in FIGURES 2 and 3 is in the order of fourteen degrees, and the offset 102 is in the order of one-quarter inch. As noted above, the towing force imposed on the trailer hitch 14 provides the desired rotational orientation of the axle 22 to attain the positive caster for each direction of trailer movement. FIGURES 2 and 3 show that an arm 112 is linked at one end to the tow hitch 114 and linked at the other end to a second arm 114 that connects to a crank arm 116. This multi-arm linkage, with the crank arm 116 keyed or otherwise fastened to the axle for rotation therewith, couples the movement of the tow hitch to the axle 22. A spacer block 110, indicated in FIGURE 2, is inserted to lock the tow hitch in the forward direction for general forward towing at traffic speeds. FIGURE 1 further shows that a track arm 118 is secured to each wheel spindle 100 and that a track rod 120 interconnects the free ends of the track arms. This interconnection of the two wheel spindles assures that the two wheels turn through like angles and hence remain parallel. A steering damper 122, suitably a shock absorber, is connected between the track rod 120 and the dolly chassis 12, illustratively to the axle bar 38. Further, as shown in FIGURES 1 and 7, the wheels can be locked in a straight direction, to prevent them from turning, by means of a stop arm 124 hinged to the axle bar 38 of the chassis 10 and which seats between a pair of spaced stops 126, 128 fixed to the track rod 120 when the wheels are in the straight position, as appears in FIGURE 1. A tension spring 130 is connected between the remote end of the stop arm 124 and the axle bar 38 for imposing a toggle-like bias on the stop arm 124. That is, the spring 130 has less extension, and hence is under less tension, when the stop arm 124 is either in the locked position shown in solid lines in FIGURE 7 or in the full unlocked position illustrated there with broken lines. In betweeen these two positions, the spring 130 is extended and under greater tension. FIGURES 10 and 11 show that the dolly 10 preferably is fitted also with a stabilizing foot 132. The illustrated foot employs a foot member 134 carried on the end of a leg stem 136. A support tube 138, secured to the chassis 12, supportingly carries the leg stem for movement between a telescopically retracted, nested, towing position shown in FIGURE 11 with broken lines, and a telescopically projecting, extended stabilizing position shown in FIGURE 10 and, with solid lines, in FIGURE 11. The support tube 138 is angled across the chassis 12, as FIGURE 11 shows, to locate the foot member 134 behind and midway between the wheel 16 and 18 when in the extended position. The tube 138 also is angled vertically to place the extended foot member 134 on the ground. In this position, the foot 132 stabilizes the dolly oriented upright, as shown in FIGURES 1 and 2, for lifting a vehicle into the towing position. The foot thus allows the dolly to lift a vehicle without requiring any restraint on the tow hitch, as by connection to a towing vehicle. In the nested position, on the other hand, the foot member is clear of the ground for unobstructed dolly towing. Provision can be made for selectively latching the leg stem in each position. It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained. Since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompaying drawings be interpreted as illustrative and not in a limiting sense. The intent of the following claims is to cover all of the generic and the specific features of the described invention, and all statements of the scope of the invention which, as a matter of language, fall therebetween. Having described the invention, what is claimed as new and secured by Letters Patent is:

Claims: Whafc is claimed is: 1. Vehicle-towing dolly apparatus having axle means mounting spaced-apart wheel means for rotation about at least a first rotation axis, forwardly-extending tow means connected with said axle means for the towing of the dolly apparatus* vehicle-lifting derrick means mounted on the axle means for rotating, about an axis parallel to and spaced above said first wheel rotation axis, between a lowered rearwardly-extending first position and a raised upstanding second position, connection means carried with said derrick means for engagement with a towed vehicle when said derrick means is in said first position, and for lifting the towed vehicle as said derrick means moves to said second position, winch means mounted with said tow means and connected with said derrick means for moving said derrick means from said first position to said second position, and further having the improvement comprising vehicle stop means mounted with said derrick means for facing a vehicle to be towed when said derrick means is in any of said first and second positions and accommodating without significant resistance vertical movement of the vehicle to be towed relative to said derrick means during the lifting of that vehicle by said derrick means. 2. Apparatus according to claim 1 wherein the bumper element of the vehicle to be towed moves relative to said stop means in a direction between a lower third position and an upper fourth position during the lifting of the vehicle with the lifting of said derrick means from said first position to said second position, and further comprising means mounting said stop means with said derrick means for movement relative too said derrick means between a lower position adjacent said third position and an upper position adjacent said fourth position, thereby to accommodate the relative vertical movement of the vehicle to be towed. 3. Apparatus according to claim 2 further comprising means resiliently biasing said stop means to said lower position thereof. 4. Apparatus according to claim 1 in which said derrick means extends longitudinally from a rotational connection to said axle means to an outer end that is disposed uppermost on said derrick means when raised to said second position, and further comprising means mounting said stop means adjacent said outer end of said derrick means, and means for maintaining said stop means facing substantially horizontal during movement of said derrick means between said first and second positions, for said facing of a vehicle to be towed. 5. Apparatus according to claim 1 further comprising a first elongated sleeve member mounted with said tow means for rotation about a substantially horizontal axis, and a second elongated guide member telescopically interfitting with said first member and mounting said stop means adjacent the end of said OMPI &y derrick means which is uppermost when in said second position. 6. Apparatus according to claim 5, further comprising means providing a rotational connection of said derrick means to said second member, whereby second member moves relative to said first member during the movement of said derrick means between said first and second positions thereof. 7. Apparatus according to claim 5 further comprising lock means engaged with said first and second members for locking telescopic extension therebetween and selectively releasable for allowing such telescopic extension. 8. Vehicle towing apparatus movable on rotatable wheel means mounted on chassis means and having derrick means for connection to a vehicle for the lifting of the vehicle and for the towing of the vehicle, upon movement thereof, said derrick means being rotatable relative to said chassis means between a lowered, rearwardly-extending first postiion for connection to the vehicle and a raised upright second position for towing the lifted vehicle, and wherein said derrick means subjects the vehicle bumper element to vertical movement relative to the derrick means during derrick means rotation between said first and said second positions, and further having the improvement comprising vehicle stop means mounted with said derrick means for facing the vehicle to be towed when said derrick means is in any of said first and second positions, and for abutment with the vehicle bumper element in any of said first and second positions. 9. Vehicle towing apparatus according to claim 8 further comprising mounting means affixing said stop means to said derrick means, said mounting means being movable for maintaining said vehicle-facing orientation of said stop means and being movable for accommodating movement of said stop means vertically relative to said derrick means with said relative vertical movement of a vehicle bumper element abutted with said stop means. 10. Vehicle towing dolly apparatus having axle means mounting spaced-apart wheel means for rotation about at least a first rotation axis, forwardly-extending tow means connected with said axle means for the towing of the dolly apparatus, vehicle-lifting derrick means mounted on the axle means for rotating, about an axis parallel to and spaced above said first wheel rotation axis, between a lowered rearwardly-extending first position and a raised upstanding second position, connection means carried with said derrick means for engagement with a towed vehicle when said derrick means is in said first position, and for lifting * the towed vehicle as said derrick means moves to said second position, winch means mounted with said tow means and connected with said derrick means for moving said derrick means from said first position to said second position, and further having the improvement wherein said connection means comprises first tension means having at one end a selectively adjustable connection to said derrick means adjacent the outer end thereof and having at the other end engagement means for connection to a vehicle for the lifting and the towing of that vehicle, and second tension means arranged for connection at one end to said first tension means proximal to said engagement thereof to the vehicle, and having a selectively adjustable connection to said dolly apparatus proximal to the rotational connection of said derrick means, with said axle means whereby, upon connection and lifting of a vehicle with said dolly apparatus, said first tension means, said second tension means and said derrick means form, in vertical projection, a triangular structure with said derrick means forming one triange side and each said tension means forming a separate triangle side. 11. Vehicle towing dolly apparatus movable on rotatable wheel means mounted on chassis means and having derrick means for connection to a vehicle for the lifting of the vehicle and for the towing of the vehicle upon movement thereof, said wheel means including first and second spaced-apart wheels, each of which is mounted on a wheel spindle pinned by king pin means to a different end of an axle member rotatable to either of first and second positions, each pin means being angled from the vertical for providing positive wheel caster for forward movement in said first rotational position and for providing positive wheel caster for rearward movement in said second rotational position, and comprising the improvement comprising means providing a vertical offset between f OMPI the axis of said axle member rotation and each spindle axis about which one said wheel rotates. 12. Apparatus according to claim 11 comprising the further improvement wherein each said wheel spindle mounts to said axle member with the wheel rotation axis thereof offset vertically below the rotation axis of said axle member, thereby to bias said axle member to maintain either of said first and second rotational positions. 13. Apparatus according to claim 11 further comprising damping means connected between said chassis means and said spindle means for damping turning of either wheel means about the pin means mounting thereof. 14. Vehicle towing apparatus according to claim 1 further comprising frame means mounting said axle means and said tow means and said derrick means, and foot means movably mounted on said frame means for movement between an extended ground-engaging apparatus-stabilizing position and a retracted and nested apparatus-towing position.

Inventors: SILVA JOHN C JR, SILVA, JOHN, C., JR.
Applicants: SILVA JOHN C JR, SILVA, JOHN, C., JR.
Application year: 1983
Main classification: B60P3
IPC codes: B60P3