GB2082992A

GB2082992A - Mounting for a Vehicle Towing Hitch

Info

Publication number: GB2082992A
Application number: GB8113424A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-09-04
Filing date: 1981-04-30
Publication date: 1982-03-17
Also published as: GB2082992B

Abstract

Guide 10, comprising back plate 11, flanges 13, and end plates 15 can be secured by bolts (not shown) through holes 14 to a towing vehicle (not shown). A positioning member in the form of a threaded rod 40 is retained in the guide 10 by nuts 41 located in resilient bushes. Located in the guide 10 by two opposite edges of flanges 48 and by runners 49 is a shoe 46 having holes 28 for mounting a towing hitch (not shown) thereto. The shoe 46 has a clamping arrangement 102 comprising a jaw 50 capable of positive engagement with the rod 40. Loosening the clamping arrangement 102 allows for adjustment of the shoe and towing hitch to any desired vertical position. Once in position the clamping arrangement is tightened, which brings the jaw 50 into positive engagement with the rod and forces the flanges 48 into engagement with the rod 40. The clamping arrangement 102 can be replaced by a nut threadedly engaged with the rod 40 so that rotation of the rod 40 raises or lowers the shoe 46. <IMAGE>

Description

SPECIFICATION Mounting for a Vehicle Towing Hitch This invention concerns a mounting for a vehicle towing hitch.

When a trailer is coupled to a towing vehicle, it is usually appropriate for the drawbar of the trailer to be substantially parallel to the ground. This is particularly the case with the heavy and/or fourwheel trailer, to ensure proper coupling and the minimum of adverse effect by the trailer on the towing vehicle. Generally, the towing hitches of towing vehicles, such as so-called land-rovers and equivalent vehicles, are non-adjustably mounted, so that there is no practical possibility of coordinating the height of the hitch to the trailer to achieve horizontality of the trailer's drawbar.

An object of the present invention is to provide a vehicle towing hitch mounting which can be adjusted for height to enable a hitch mounted thereto to be co-ordinated to the heights of different trailers.

With this object in view, the present invention provides a vehicle towing hitch mounting comprising a slotted boxsection guide providing opposed recesses facing one another at opposite sides of a web adapted for mounting on a vehicle, a positioning member extending longitudinally of the guide between the recesses and mounted so as to be restrained against significant axial displacement, and a shoe adapted for a towing hitch to be mounted thereon, the shoe being located, by opposed sides thereof engaging in the recesses, for movement along the guide and adapted to be held in a desired position along the guide by the positioning member.

Preferably the positioning member is a threaded rod, and the shoe may be in threaded engagement with the positioning member so that rotation of the latter moves the shoe along the guide.

The shoe may be provided with clamping means to engage with and disengage from the positioning member and preferably the clamping means is a jaw carried by the shoe and which clamps the shoe to the positioning member. The shoe is conveniently of inverted U shape so that it locates snugly in the guide.

The shoe may carry a packing piece which locates in and is displaceable along the slot between the confronting free edges of the guide, at the recesses.

To ensure that, in use, pitching or other up and down movements of a towbar connected to the mounting are not transmitted through the mounting, the positioning member is preferably located, in end plates of the guide, by resilient means. This resilient means may comprise, adjacent each end of the positioning member, a respective flanged sleeve extending through the respective end plate and having a resilient body disposed between the flanges and the respective end plate.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a front elevation illustrating a first embodiment of the mounting for a vehicle towing hitch of the invention; Fig. 2 is a sectional side view taken on the line 2-2 of Fig. 1; Fig. 3 is a sectional plan taken on the line 3-3 of Fig. 1; Fig. 4 is a front elevation illustrating a second embodiment of the mounting for a vehicle towing hitch of the invention; Fig. 5 is a sectional view taken of the line 5-5 of Fig. 4; and Fig. 6 is a sectional plan taken on the line 6-6 of Fig. 4.

Throughout the following description, similar reference numerals have been allocated to like parts.

The embodiment of the vehicle towing hitch mounting of the invention illustrated in Figs. 1 to 3 of the drawings comprises a guide 10 in the form of a metal component of slotted box section.

The shape of this section is such as to provide a planar back plate 11, of rectangular configuration, having protruding side webs 12 along its two opposite longitudinal edges, each such side web 1 2 having a respective inwardly directed flange 13. These two flanges 1 3 and their respective side webs 1 2 define facing recesses 100 along the opposite longitudinal sides of the back plate 11. The facing free edges of the flanges 1 3 define between them a slot, indicated by the numeral 101, along the guide 10.The planar back plate 11 has there-through holes 14 which enable the entire mounting to be bolted to an appropriate part of the chassis of a towing vehicle (not shown) with the back plate 11 in a substantially vertical plane and the longitudinal dimension of the guide upright.

At top and bottom, end plates 1 5 are secured, as by welding, to the back plate 1 1, the side web 12 and the flanges 13. Extending longitudinally of the guide 10, vertically and midway between the recesses 100, is a positioning member in the form of a screw 1 6. This screw 1 6 has, on each end, a respective flanged sleeve 17 extending through a respective hole in the respective end plate 1 5 and abutting by its non-flanged end against a respective retaining nut 1 8 disposed externally of the guide 10.Within the guide 10, each such sleeve 1 7 is surrounded by a respective resilient bush 19, e.g. of rubber, which is disposed between the respective end plate 1 5 and the flange of the sleeve 1 7. A respective retaining cup 20 surrounds the resilient bush 1 9 to restrain outward expansion of the bush 1 9 whilst permitting restricted axial movement of the sleeve 17 and the adjusting screw 1 6. This axial movement is only sufficient to enable the resilient bushes 1 9 to absorb shocks acting in the axial direction of the screw 16, and significant axial displacement of the screw 1 6 does not occur, of course, because the bushes 1 9 are effective to tend to retain the screw 1 6 in a predetermined rest position.

The retaining nut 1 8 at the upper end of the screw 1 6 has a tommy bar 21 extending through it and through the screw 1 6 to enable the screw 16 to be rotated manually.

Threadedly engaged on the screw 1 6 is a positioning nut 22 to which is secured a shoe23.

This shoe 23 is of inverted-U shape providing shallow flanges 24, slidingly locating in the opposed recesses 100 of the guide 10, and a connecting web 25 which bridges the screw 1 6 and has the nut 22 secured to it. The shoe 23 carries a rectangular packing piece 26 which is disposed in the slot 101 between the facing flanges 13 of the guide 10 and moves along the slot 101 when the shoe 23 is displaced along the screw 16. A locking nut 27 is also provided on the screw 1 6 at a location wherein it can be tightened against the positioning nut 22.

Both the shoe 23 and the packing piece 26 fastened thereto are adapted, by the provision of holes 28 therethrough, for a towing hitch (not shown) to be secured thereto.

The mode of operation of the mounting will readily be understood from the foregoing description. With the guide 10 bolted, by its back plate 11 , to a vehicle as described, and a towing hitch bolted to the shoe 23 and packing piece 26, rotation of the positioning screw 1 6 (by means of the upper retaining nut 18) has the effect of raising or lowering the shoe 23 and therewith the towing hitch whose height above ground can thereby be adjusted so that when a trailer (not shown) is coupled thereto, the drawbar of the trailer is substantially horizontal. Accordingly, the towing hitch can be adjusted, as necessary, for towing different trailers having towbars at different heights.Locking of the height of the hitch can, of course, be effected by tightening of the locking nut 27 against the positioning nut 22 and this locking nut 27 will, of course, have to be released each time the height of the hitch is to be adjusted.

The second embodiment of the vehicle towing hitch mounting of the invention illustrated in Figs.

4 to 6 comprises a guide 10 of configuration similar to the guide 10 of the embodiment of Figs.

1 to 3, having a planar back plate 11, protruding side webs 12 each of which has an inwardly directed flange 13, and end plates 1 5. The back plate 11 has therethrough holes 14 which enable the entire mounting to be bolted to a towing vehicle (not shown).

A threaded positioning rod 40 is mounted longitudinally of the guide 10 so as to extend vertically and midway between the recesses 100, and is secured at each end by a respective retaining nut 41 comprising a head part 42 and a sleeve-like extension 43 which locates in an aperture in the respective end plate 1 5. The nut head 42 is disposed externally of the guide 1 0 and the nut 41 is locked against rotation on the rod 40 by a respective security pin 44 which extends through the rod 40 and the respective nut 41. Outside the guide 10, each sleeve 43 is surrounded by a respective resilient bush 19, e.g.

of rubber, which is accommodated between a respective cup 20 and the nut 41. The cup 20 surrounds the resilient bush 19 to restrain outward expansion of the latter whilst permitting restricted axial movement of the nut 41 and the rod 40.

Fixed to the lower end plate 15, so as partially to surround the corresponding nut 41, bush 19 and cup 20, is a shieid 45 which serves to protect the parts from damage.

Located within the guide 10 and clampable to the rod 40 is a shoe 46. This shoe is of inverted-U shape providing a connecting web 47 having shallow flanges 48 disposed across the slot 101 of the guide 10. Connected to opposed free ends of the flanges 48 so as to extend parallel to the axis of the rod 40 are runners 49. The connecting web 47 carries 'a packing piece 26 disposed in the slot 101 between the facing flanges 13 of the guide 10, and a clamping arrnngeme-1t ind'cated generally by the numeral 102.

The clamping arrangement 102 comprises a clamp support 80 and a jaw 50 mounted under the web 47. The jaw 50 has a thread clamping claw 54 connecting to one end of stud bearing web 55. The claw 54 has protrusion (not illustrated) which can positively engage with the rod 40. A pivot tongue 56 connects to the other end of the stud bearing web 55, and this tongue 56 abuts against the underside of the web 47 of the shoe 46.

A threaded stud 51, having one end located in the web 55, extends through the web 47 of the shoe 46. A spring 52 located on the stud 51 serves to urge the jaw 50 away from the rod 40 and a locking nut 53 locks the stud 51 in the jaw 50. Threadedly engaged with the stud 51 at the opposite side of the web 47 is a clam ping nut 58.

As with the first embodiment, the shoe 46 and the packing piece 26 are adjusted, by the provision of holes 28 therethrough, for a towing hitch (not shown) to be secured thereto.

The mode of operation of the mounting will readily be understood from the foregoing description, starting with the guide 10 bolted, by its back plate 11, to a towing vehicle, and a towing hitch bolted to the shoe 46 and packing piece 26, and the clamping arrangement 102 slack, the shoe 46 is moved to the desired position relative to the guide 1 0. The clamping nut 58 is then tightened on the stud 51 and accordingly draws the claw 54 of the jaw 50 into positive engagement with the rod 40, whilst simultaneously bringing the flanges 48 and the clamp support 80 into engagement with the rod 40 so securing the shoe 46 in the desired position which provides for the drawbar of a trailer (not shown) to be substantially horizontal when connected to the hitch.

This embodiment of the mounting for a vehicle towing hitch of the invention has the advantage that the shoe 46 can be adjusted rapidly from one position to another by undoing the clamping nut 58, moving the shoe 46 to a new position and then tightening the nut 58. Another advantage is that any corrosion which may occur at the rod 40 will not unduly inhibit movement of the shoe 46 from one position to another.

The invention is not confined to the precise details of the foregoing examples and variations may be made thereto. Thus, for instance, the arrangement of the resilient mountings (if provided) of the positioning member may be either inside or outside the guide. An electrical socket, compatible with electrical connecting plugs of trailers, may be mounted on one of the side webs or one of the flanges of the guide.

Different clamping arrangements may be provided for clamping the shoe. One such arrangement may comprise, for example, a jaw similar to the jaw 50 but bearing a stud extending through the shoe and connected to a cam rotatable by means of a lever, the cam resting on the shoe so that rotation of the cam, by the lever, about its connection with the stud, moves the jaw towards or away from the threaded rod 40 or other positioning member. The nature of the cam and lever may be such that when the free end of the lever is against the shoe the clamping arrangement is locked. Such an arrangement may be a so-called quick-release or snap action device.

Claims

Claims

1. A vehicle towing hitch mounting comprising a slotted boxsection guide providing opposed recesses facing one another at opposite sides of a web adapted for mounting on a vehicle, a positioning member extending longitudinally of the guide between the recesses and mounted so as to be restrained against significant axial displacement, and a shoe adapted for a towing hitch to be mounted thereon, the shoe being located, by opposed sides thereof engaging in the recesses, for movement along the guide and adapted to be held in a desired position along the guide by the positioning member.

2. A mounting as claimed in claim 1 wherein the positioning member is a threaded rod.

3. A mounting as claimed in claim 2 wherein the shoe is in threaded engagement with the positioning member so that rotation of the latter moves the shoe along the guide.

4. A mounting as claimed in claim 1,2 or 3 wherein the shoe is provided with clamping means to engage with and disengage from the positioning member.

6. A mounting as claimed in any preceding claim wherein the shoe is of inverted-U shape.

7. A mounting as claimed in any preceding claim wherein the shoe carries a packing piece which locates in and is displaceable along the space between confronting free edges of the guide, at the recesses.

8. A mounting as claimed in any preceding claim wherein the positioning member is located, in end plates of the guide, by resilient means.

9. A mounting as claimed in claim 8 wherein the resilient means comprises, adjacent each end of the positioning member, a respective flanged sleeve extending through the respective end plate and having a resilient body disposed between the flange and the respective end plate.

10. A vehicle towing hitch mounting substantially as hereinbefore described with reference to and as illustrated in Figs.1,2 and 3, or in Figs. 4, 5 and 6, of the accompanying drawings.