WO1992012867A1

WO1992012867A1 - A coupling device and a method for converting a ball hitch to a different hitch type

Info

Publication number: WO1992012867A1
Application number: PCT/FI1992/000009
Authority: WO
Inventors: Juha Olavi Nyman
Original assignee: Juha Olavi Nyman
Priority date: 1991-01-16
Filing date: 1992-01-15
Publication date: 1992-08-06
Also published as: AU1157192A; FI910239A; FI90843B; FI910239A0; FI90843C

Abstract

The invention relates to a connector piece (6) for trailing devices, said piece being intended for co-operating with a ball socket (3) of a ball pin hitch head (2) arranged at the end of a trailer tongue of said trailer device. Said connector piece (6) comprises a conventional hitch ball (7) co-operating with said ball socket (3) of said hitch head (2), as well as a lower support (8) holding said hitch ball (7). Desired connector means (9) extend from said lower support (8) in one direction and side support means (10, 10A) extend in the opposite direction, said support means having transverse pieces (12) extending over said trailer tongue (1) and comprising fastening means (13) co-operating with said trailer tongue (1). According to the invention the hitch method of said trailing device is converted by connecting a connector piece (6) to said hitch head (2) of said trailer tongue (1). Said device is tilted into a direction essentially along the trailer tongue (1). Said fastening means (13) is separately locked to a counter means (14) on said trailer tongue (1) and said hitch ball (7) of said auxiliary device (6) is locked into said ball socket (3) of said hitch head (2).

Description

A Coupling device and a method for converting a ball hitch to a different hitch type.

The present invention relates to a connector piece for trailing devices, said piece being designed for σo-operation with a hitch head adapted for ball pin connection and arranged at the end of the trailer tongue of said trailing device. The invention further relates to a method for con¬ verting the method of pulling a trailing device having, at the end of a trailer tongue, a conventional ball pin coupling hitch head with a ball socket and locking means.

The object of the invention is to make it possible to con¬ vert the coupling of a trailer or the like trailing device having a ball pin coupling also into another method of coupling which is different from said ball pin coupling method, such as into one suitable for hook, link and the like coupling.

Such coupling devices are known from brochures and catalogues of manufacturers in this field. In said known coupling devices conversion from one method of coupling into another is effected by detaching the hitch head of the ball pin connector from the trailer tongue, or from some other attachment point, whereafter a device representing the desired coupling method is attached instead.

In known arrangements for converting the coupling method there is the disadvantage that for changing the coupling method the ball pin coupling devices must be detached from their point of attachment prior to attaching the device corresponding to the desired coupling method at said point of attachment. For each conversion of the coupling method this demands one detachment and one attachment operation. Taking into consideration the range of uses for a ball pin coupling and the pulling speeds permitted for such couplings, the detaching and attaching of the ball pin con¬ nector devices increase the risk of accidents due to a pos¬ sible insecurity in connection with the re-attachment of the ball pin coupling. In Swedish open laid application 8403774-6 there is disclosed a hitch arrangement having, under the proper hitch head, another hitch device, which is permanently attached, the intention being to move the hitch head itself to the outer end of a lever mechanism, in order to move the virtual pivot point of the combined puller- trailer to a point under the puller. This device is mainly intended for fixed installation, and the installing or removing of the apparatus is neither easy nor quick.

Coupling arrangements are also known, where the pulling device of a vehicle comprises coupling means for many different coupling methods, said device comprising revolvingly arranged hooks, ball pins or the like for the various coupling methods. The device to be used is selected according to the pulling method of the trailer' s coupling device. This is a technically difficult construction which imposes high demands on the strength of the material used.

The ob ect of the present invention is to provide a new type of coupling device, which in use allows the original trailer tongue structure to remain unaffected, thus preserving its reliability and for instance the function of the brake device unchanged, the conversion of the coupling method at the same time being quick and simple, without any negative impact on the security. This kind demand for converting the pulling system appears in the trailers and the like of fire brigades and rescue services, where the pulling method should be quickly adapted to the pulling method of any pulling device which happens to be at disposal. It is con¬ sidered important that any auxiliary device should be both easy to mount and at the same time, essentially unmovingly supported on the original hitch head. A weak or insufficient support would cause the auxiliary device under load to move to some extent around the ball, with respect to the original hitch head, which would establish a mechanism constituting a considerable security risk and wear risk.

The present invention requires only one connecting or dis¬ connecting operation when an existing coupling method is con¬ verted into the desired coupling method, a completely stiff attachment of the auxiliary device still being obtained. The characteristics of the invention are evident from the appended claims, which are considered a part of this speci¬ fication. The coupling piece according to the invention comprises a conventional hitch ball being adapted for co¬ operation with the ball socket of the hitch head. The hitch ball is fixedly connected to a lower support holding said hitch ball and the coupling means for the pulling vehicle extend from said lower support in one direction and elongated side support means extend into the opposite direction at least on one side of said trailer tongue, said support means being directed essentially in the direction of said trailer tongue and comprising fastening means separate¬ ly co-operating with a counter means arranged on said trailer tongue.

In the method according to the invention an auxiliary device is threaded over the the trailer tongue head, said auxiliary device having, in addition to a forward extending coupling means for a second hitch method, a ball attached to said lower support and co-operating with said ball socket on said trailer tongue. Fastening means on said side support means connected to said lower support are correspondingly con¬ nected to counter means located separately on said trailer tongue at a distance from said ball socket.

According to the invention the connector piece used to con¬ vert the hitch method is connected directly to said ball pin hitch from below. Said connector piece comprises a straight or bent body, said body being preferably at its rear portion, or along a length corresponding to the length of said ball pin hitch, in contact with the lower hem of said ball socket and to a part of the ball pin coupling of the trailer tongue. The forward portion is shaped in accordance with the desired hitch method, said auxiliary device being, as such, connectable to the available pulling vehicle. On the top side of said body there is a ball pin to be attached to said ball pin hitch, whereby said connector piece will be placed below the ball pin hitch of said trailer tongue or any other fastening point, and will be fastened to said ball pin hitch by a fastening method which securely keeps the fastening piece and body of said coupling device in contact with the surface of said ball pin hitch close to and around said ball pin hitch.

The invention will now be described in greater detail with reference to the drawings, in which

Fig. 1 shows a connector piece according to one embodiment of the invention, said piece being shown partly in section and fitted to said ball pin hitch and seen from the side, the alternative hitch method comprising, in the shown case, a hook,

Fig. 2 shows the coupling piece according to Fig 1 as seen from above, and

Fig. 3 discloses an alternative embodiment having one side open.

In Figure 1 preferred favourable embodiment is disclosed, said embodiment comprising side support means further inter¬ connected by a transverse piece extending transversely to and preferably on the top side of said trailer tongue. Thus Fig. 1 shows the trailer tongue 1 of said trailing device, the forward located portion of said tongue comprising a con¬ ventional ball pin hitch arrangement comprising a hitch head 2 with ball socket 3 and locking lever 4. Said hitch head is attached to said trailer tongue 1 e. g. by extending bolts 5, 5A extending through said tongue. If said trailing device comprises brakes and any reversing automatics (not shown), the trigger device for these will be located between said trailer tongue 1 and said hitch head 2, said hitch arrange¬ ment usually being fixed by said bolts 5, 5A to said device trigging the brakes.

Fig. 1 further shows a preferred embodiment of the in¬ vention, said embodiment comprising an auxiliary device i. e. a connector piece 6 having a hitch ball 7 known per se, said ball fitting into the ball socket 3 of said hitch head 2 and being lockable thereto by said locking lever 4, said hitch ball 7 transmitting the actual pulling force between said connector piece 6 and said hitch head 2 fixed to said trailer tongue 1. Said hitch ball 7 of said connector piece 6 is fixed to the lower support 8 of said body, in the for¬ ward end of which there is a coupling means 9 in accordance with the alternative hitch method, which means 9, especially in connection with the embodiments according to Figs. 2 and

3 is disclosed as a ring arrangement being suitably rotatable around a horizontal axis with respect to said connector piece 6, to which arrangement a conventional draw¬ bar of a farm tractor, snowmobile or the like fits, said drawbar being known per se. In both cases the coupling means for the alternative hitch method may, in accordance with the invention, be arranged at least essentially in line with the pulling force exerted upon the primary hitch head, in other words, the connector means may constitute a direct extension of the trailer tongue.

In Fig. 1 and especially in Fig. 2 a side support means 10 according to the invention is shown, said means 10 extending from said lower support 8 backwards along said hitch head 2 to its upper side. Said side support means 10 is intended for locking the position of said connector piece 6, with the aid of a lengthy support lever, essentially preventing said hitch ball 7 from moving in said ball socket 3. Thus the actual pulling force will be directed towards said hitch ball 7, but those forces which tend to sway or twist said connector piece 6 in relation to said trailing tongue 1 will be transmitted via a transverse piece 12 located at one end of said side support means 10 and via its fastening means 13 to said trailer tongue 1. Thus all such movements may be effectively prevented. This rigidity will increase due to the close fit of the upper surface 16 of said lower support 8 and/or the support portions 18, 18A of said side support means 10 to said hitch head 2 and its hem 17, as disclosed below.

In the embodiment more closely disclosed in Fig. 2 said side support means comprise branch means 10, 10A located on both sides, said branch means being interconnected, on the upper side of said hitch head and/or said trailer tongue, by said transverse piece 12 preferably resting on said upper surface 11. Said transverse piece 12 comprises a fastening means 13 co-operating with counter means 14 located on said trailer tongue 1 and/or in said hitch head 2. In the preferred embodiment according to Figs. 1 and 2 said counter means 14 are constituted by one of said fastening bolts 5 for said hitch head 2, which bolt suitably is extended upwards and preferably has a butterfly nut 15 or the like to achieve a locking.

According to a preferred embodiment especially shown in Fig 2 said fastening means 13 on said transverse piece 12 com¬ prise an oblong notch, groove or the like formation, whereby said transverse piece 12 may be brought into engagement with an extended fastening screw 14 without completely loosening said locking nut 15. In the scope of the invention said fastening means 13 may, however, be substituted by some other kind of means, which essentially fixedly connect said transverse piece 12 in a position above said trailer tongue 1. In some embodiments a latch, peg or the like locking arrangement is adapted in place of said fastening means 13 and counter means.

In Fig. 1 there is shown a detail of an especially preferred embodiment of the invention, that is the feature that the upper surface 16 of said lower support 8 is located at least partially closely against said lower hem 17 of said ball socket of said trailer tongue, whereby an especially firm locking between said connector piece 6 and said hitch head 2 is achieved. Fig. 2 on the other hand shows another preferred detail i. e. that said side support means 10, 10A comprise portions 18, 18A fitting at least partly closely against the outer sides of said hitch head. Especially in the embodiment comprising branch means 10, 10A extending on both sides, said branch means 10, 10A favourably comprise portions 19, 19A having a broader gap between them, as shown more clearly in Fig. 2, whereby the threading of said con¬ nector piece 6 over said hitch head 2 will be facilitated.

In the embodiment according to Figs. 1 and 2 the auxiliary device 6 will be fastened to said hitch head 2 by passing said device 6 over said hitch head 2 and turning it over essentially into a direction co-linear with said trailer tongue 1, so that said fastening device 13 of said trans¬ verse piece 12 will meet said counter piece 14 located at said upper surface 11 of said trailer tongue 1, and said hitch ball 7 will set into said ball socket 3 of said hitch head 2. Said fastening means 13 of said transverse piece 12 is then locked to said counter means 14 and said hitch ball 7 of the auxiliary device 6 is locked into said ball socket 3 of the hitch head 2.

In accordance with Fig. 3 another preferred embodiment of the invention comprises one preferably flat side support means 10 located on one side and one end of said support means comprises an upper transverse piece 12. In this embodiment the whole connecting piece 6 is open from the side, whereby said piece may be passed over said hitch head 2 also from the side. In this case said fastening means 13 on said transverse piece preferably comprise an oblong notch or the like, which extends transversely to the trailer tongue 1, whereby passing said notch around said fastening bolt 5 is especially easy. Since the whole locking force in the disclosed embodiment will act only upon one side support means 10 it is preferred to have a separate stiffening girder 22 or the like. This embodiment further requires the material of said fastening bolt 5 has properties which are dimensioned against an unequal stress acting especially in the lateral direction.

Figure 4 shows an alternative embodiment intended especially for heavier trailers having the hitch head fastening arranged with laterally extending fixing bolts. In this embodiment a standard transverse fastening bolt is replaced by a special bolt 5 both ends of which preferably comprise threaded portions extending outwards from the hitch head. At these portions butterfly nuts 15 or the like locking means may be attached. In this embodiment there are specially arranged fastening devices 13 mounted directly on said side support means 10, 10A. In the shown embodiment said fastening means 13 are formed by preferably oblong notches open at one end, which notches are directed essentially backwards in relation reference to the pulling direction, suitably in the extended direction of said side support means.

Figure 4a shows an enlarged view of an alternative arrange¬ ment of the embodiment disclosed in Fig. 4, wherein said oblong notches 13 extend essentially open and inclined for¬ ward with respect to the pulling direction. In this embodi¬ ment the fastening of the device is especially easy, because the fastening may be performed in two steps. In the first step said notch portions 13 of said side support means 10 , 10A are passed onto said extended fastening bolts 5, whereby the auxiliary device 6 as such will remain in position and the fitting of the ball is easy. Only after this step will said ball 7 of the auxiliary device be raised into position in said ball socket 3 and be locked therein.

Figure 4 further shows schematic view of an alternative fastening arrangement or one that may be used in connection with some other fastening. In this arrangement said fastening devices are formed by locking pieces 23 extending essentially around said trailer tongue 1. Said locking pieces are preferably formed by extension pieces 24 located at said side supports 10, 10A or at support portions located at the sides, said extension pieces being interconnected by a transverse latch 25 located movably and separately lockable above the trailer tongue. In this case the upper surface 11 of said trailer tongue 1 or hitch head 2 suitably acts as counter piece for said locking piece 23, whereby the counter support for said transverse latch 25 suitably will be constituted by a separate support shoe 26 resting on the trailer tongue and fixed to said side support means 10, 10A or to an extension of said lower support, by corresponding support claws on both sides, or by another corresponding support, for example by the contact between said oblong notch 13 and said fastening bolts 5.

Fig. 1 further shows a section view of a preferred detail which is also especially well suited for use in connection with a one-sided connector piece according to Fig. 3. In the disclosed case the lower surface of said transverse piece 12 is partly or totally slightly inclined in relation to the longitudinal axis of the trailer tongue 1, so that there will be formed an inclined locking portion 20. In this case the transverse piece may easily be brought into a position between said counter means 14 or said fastening bolt 5, where said hitch ball 7 still is free and located under said ball socket 3 on said hitch head 2. Thereafter said hitch ball 7 is locked into said ball socket 3, after which said locking nut 15 or the like will be tightened around said fastening means 13 of said transverse means 12 for establishing a dependable locking. In this embodiment said trailer tongue 1 or hitch head 2 comprise, at the respective upper surface 11, also an inclined counter surface 21, against which said inclined locking portion 20 of said transverse means 12 will be closely settled. In one pre¬ ferred embodiment this arrangement formed by said inclined locking portion 20 and said counter surface 21 further com¬ prises separate locking claws in order to secure the attach¬ ment, as generally will evident from the section view of Fig. 1.

Above some favourable embodiments of the invention have been disclosed, where relatively slow vehicles like farm tractors or the like are used as pulling devices. It is, however, apparent, that the invention will not be restricted to these embodiment only, but the invention may, i. a. as far as the connector means 9 is concerned and otherwise be more broadly applied within the scope of this specification, the accompanying figures and the appended claims.

Claims

1. A connector piece for trailing devices, said piece being intended for use in connection with a hitch head arranged for ball pin connection at the end of a trailer tongue (1) of said trailing device, said connector piece (6) comprising a hitch ball (7) of a kind known per se, said ball being intended for co-operation with a ball socket (3) of said hitch head (2), as well as a lower support (8) holding said hitch ball (7), whereby connector means (9) arranged for a pulling vehicle extend in one direction from said lower support (8), c h a r a c t e r i z e d in, that elongated side support means (10, 10A) extend essentially parallel with said trailer tongue (1) in the opposite direction on at least one side of said trailer tongue (1), fastening means (13, 23) being connected to said side support means (10, lOA) and independently co-operating with a counter means (14) located on said trailer tongue (1) at a distance from said ball socket (3).

2. A connector piece as defined in claim 1, c h a r a c t e ¬ r i z e d in, that said fastening means (13, 23) consists of a locking means surrounding said trailer tongue to at least an essential portion thereof, said trailer tongue (1) itself or its body portion suitably defining said counter means on said trailer tongue (1).

3. A connector piece as defined in claim 1, c h a r a c t e ¬ r i z e d in, that an extended fastening bolt (5) of said hitch head (2) defines said counter means (14), and a suitably oblong notch or slit co-operating with said bolt (5) define said fastening means (13).

4. A connector piece as defined in any of claims 1 to 3, c h a r a c t e r i z e d in, that a transverse piece (12, 25) extending on the lower or upper side of said trailer ton¬ gue (1) adjoins said side support means, said transverse piece suitably interconnecting said side support means (10, 10A) extending on both sides of said trailer tongue, whereby said side support means (10, 10A) and/or transverse piece (12, 25) preferably comprise portions resting against the surface (11) of said trailer tongue (1) and/or said hitch head (2), said portions being suitably so arranged, that a locking portion (20) resting on said surface (11) of said trailer tongue (1) and/or hitch head (2) is inclined with respect to said trailer tongue (1) in such a manner, that it extends essentially in the direction of the trailer tongue (1) when said hitch ball (7) is positioned adjacent outside said ball socket (3) of said hitch head (2), whereby said trailer tongue (1) and/or said upper surface (11) of said trailer tongue (1) or said hitch head (2) suitably comprises a counter surface (21), the inclination of which, with respect to said trailer tongue (1), corresponds to the inclination of said locking portion (20) resting thereon.

5. A connector piece as defined in any of claims 1 to 4, c h a r a c t e r i z e d in, that said lower support (8) and/or side support means (10, 10A) comprise a portion (16) and/or correspondingly (18, 18A) resting, in the vicinity of said hitch ball (7), at least partially closely against the hem (17) and/or outer sides of said hitch head (2), and that at least essentially parallel branch means constitute said side support means (10, 10A), said means suitably having a portion (19, 19a) of wider gap between themselves, the length of said portion corresponding at least to the height of said hitch head (2) and an adjoining locking lever (4).

6. A connector piece as defined in any of claims 3 to 5, c h a r a c t e r i z e d in, that a suitably at least par¬ tially flat piece extending along one side of said trailer tongue (1) constitutes said side support means (10), and an oblong notch (13) or the like preferably extends transversely with respect to said trailer tongue (1).

7. A connector piece as defined in any of claims 1 to 6, c h a r a c t e r i z e d in, that said connector means (9) arranged for said pulling vehicle comprise a coupling ring or the like piece of a coupling arrangement, which differs from a ball pin coupling, said piece being preferably located at a transverse portion of forward directed extensions of said side support means (10, 10A) and/or said branch means, essentially as an extension of the central axis of said trailer tongue (1) and preferably so, that a rotational movement of said connector means (9) around its axis is possible.

8. A method for converting the hitch method for a trailing device, said trailing device having, at the end of a trailer tongue (1), a conventional ball pin hitch head (2) with ball socket (3) and locking means (4), whereby an auxiliary device (6) is connected to said hitch head (2) of said trailer tongue (1), said auxiliary device (6) comprising, in addition to a forward located connector means (9) corresponding to a different hitch method, a hitch ball (7) connectable to said ball socket (3) of said hitch head (2) of said trailer tongue (1) and fixed to a lower support (8), c h a r a c t e r i z e d in, that fastening means (13, 23) located on side support means (10, 10A) adjoining a lower support beam (8) are correspondingly independently connected to counter means (14) located on said trailer tongue (1) at a distance from said ball socket (3), or against said trailer tongue (1) itself.

9. A method in accordance with claim 8, c h a r a c t e ¬ r i z e d in, that an extended fastening bolt for said hitch head (2) is used as said counter means (14), to which bolt a butterfly nut or the like locking means (15) is screwed, and that a notch, said notch being suitably oblong and open at one end thereof and located on said side support means or on a transverse piece (12) of said support means, is used as said fastening means (13), which is positioned around said extended fastening bolt (5) of said hitch head (2).

10. A method in accordance with claim 9, c h a r a c t e ¬ r i z e d in, that a portion comprising said fastening means (13) of said auxiliary device (6) is positioned, in the vicinity of said fastening bolt of said trailer tongue (1), in a slightly inclined position along said trailer tongue (1), so that an inclined locking portion (20) comprising said open notch is positioned under said locking means (15) on said fastening bolt, whereafter said hitch ball (7) on said lower support (8) is raised into said ball socket (3) of said hitch head (2), and said inclined locking portion (20) is locked, by said locking means (15), in and inclined position with respect to said trailer tongue (1) an preferably further under utilization of form-closed locking.