The present invention relates to a coupling device for vehicles, coupling parts includ¬ ed in the coupling device and an impact-attenuating device connected to a vehicle by the coupling device. The coupling device is mainly usable to connect implements to a vehicle, above all to work vehicles, such as trucks, delivery vans, loaders, tractors, road graders etc.

Implements can be attached both at the rear and at the front of a vehicle. Front attachments are used to connect, for instance, ploughs and rear attachments to connect, for instance, hose reels, cleaning equipment or impact-attenuators.

A coupling device for implements should be designed so as to make it possible to mount or dismount an implement in a quick, easy and safe way. Moreover the fasten¬ ing to the vehicle should be made by as small operations as possible, while at the same time the coupling device should not prevent that the vehicle can be used for other purposes.

The published US Patent Application US 2003/0099534 Al discloses a tractor with a rear implement attachment. The attachment comprises an upper and a lower point of attachment. The upper is in the form of a hole and the lower in the form of a hook. The purpose of the attachment is to hold a digging tool and at the same time reinforce the frame structure of the vehicle.

US Patent 4,773,666 also discloses a coupling device connected to a tractor. The device is arranged at the front of the tractor and comprises an upper and a lower point of attachment for an implement. The upper is in the form of a recess and the lower in the form of a U iron locking a shaft which extends in front of the front end of the tractor.

Another coupling device which is commonly used is the VV85 developed by the Swedish National Road Administration. This attachment consists of an upper point of attachment in the form of a round shaft on which two hooks of the implement can be arranged. To prevent the implement from being unhooked in use, there is a lower point of attachment in the form of a hole in the implement and on the attachment a plunger which is inserted into the hole for locking. Coupling devices as described above, however, prevent other functions of the vehicle, such as the tilting of a platform or the use of a hitch. To solve this problem, the coupling device can be releasably connected to the vehicle. A drawback of this is that the use will be inflexible, the coupling device takes up too much space to be able to be permanently carried on the vehicle, and must be fetched on the occasions when it is needed. This results in unnecessary driving and loss of time.

The invention relates to a coupling device and coupling parts according to the inde- pendent claims, with embodiments defined in the dependent claims.

The invention will in the following be described in more detail with reference to the accompanying Figures.

Figs 1 a-b show a non-connected coupling device according to the invention. Figs 2a-b show a coupling device according to the invention. Figs 3 a-b show a connected coupling device. Figs 4a-b show an adjustable embodiment. Figs 5 a-b show an impact-attenuator with a coupling device. Figs 6a-b show an impact-attenuator with a coupling device. Fig. 7 shows a coupling device with post installing equipment. Figs 8a-b shows a coupling device with an S bar. Fig. 9 shows a coupling device with a traffic routing sign.

Figs 1-3 show a coupling device (1) comprising a first coupling part (10) connected to a vehicle (2), here shown connected to the frame side members (3) of the vehicle, and a second coupling part (10) connected to an implement (6) (not shown, see Figs 5-9). The first coupling part (10) comprises an upper point of attachment (11) and a lower point of attachment (12), and the second coupling part (20) comprises a correspond- ing upper point of attachment (21) and lower point of attachment (22). The first coupling part (10) comprises a first part (13) attached to a first frame side member (3) and a second part (14) attached to a second frame side member (3). Both parts (13, 14) comprise an upper point of attachment (11) and a lower point of attachment (12).

The first part (13) comprises a first plate/sheet (15) with an upper point of attachment (11) for load take-up in the vertical direction (v), having a recess (17) for receiving a corresponding shaft (24) of the second coupling part (20). The second part (14) com- prises a second plate/sheet (16) similar to the first plate (15). The first coupling part (10) is in the preferred embodiment shown as two separate plates (14, 15) arranged one on each side of the hitch (5) of the vehicle. Another embodiment (not shown) involves replacing one or both plates by a box structure with equivalent points of attachment. The recess (17) is shown in the form of a semicircle which is open upwards to carry by the shaft (24) the second coupling part (20) and the implement (6).

In the Figure, both the first part (13) and the second part (14) comprise a plate (15, 16) with a lower point of attachment (12) with a device comprising a vertical shaft (18) for receiving a locking device (26) of the second coupling part (20). The vertical shaft (18) is vertically welded to the respective plates (15, 16). The plate (15, 16) also has a recess (19) for holding the coupling parts (10, 20) locked to each other in the vertical direction (v). The plates (15, 16) can be, for instance, two 15 mm metal sheets which are the only things projecting from the frame side members, which means that the coupling device does not prevent the vehicle from tilting the platform.

The vertical shaft (18) takes up little space across the vehicle and is positioned in the longitudinal direction so as not to prevent the use of the hitch (5), for instance on the same level as or, as shown in the Figures, in front of the hitch. Moreover the corre¬ sponding lower point of attachment (22) on the second part (14) comprises two spaced-apart points of attachment. Using previous solutions involving a transverse shaft or the like, it is not possible to arrange the lower point of attachment (22) on the same level as or in front of the hitch (5).

Both parts (13, 14) comprise fixing devices (4) for the respective frame side members (3). The two points of attachment (11, 12) of the first coupling part (10) are arranged behind the frame side members (3), i.e. the two points of attachment (11, 12) project behind the frame of the vehicle. Since the only things projecting from the frame side members are the plates (13, 14) and they do not project very much, the vehicle can tilt a platform without requiring dismounting of the plates. Furthermore there is nothing to prevent the hitch (5) from being used when the coupling device is not used, without dismounting anything.

The second coupling part (20) comprises an upper point of attachment (21) for load take-up in the vertical direction, and a lower point of attachment (22) arranged to lock the two coupling parts (10, 20) to each other and prevent any motion between them in the vertical direction.

The second coupling part (20) comprises two end plates (23) between which a shaft (24) and a beam (25) (not shown) are arranged, and a fixing device (4) for an imple¬ ment (6) or the like. The shaft (24) is used as an upper point of attachment (21), and on the beam (25) a lower point of attachment (22) is horizontally adjustable. Adjust¬ ment occurs by moving the lower points of attachment on a lower transverse square sectional element which is positioned at the bottom between the end plates (23). After adjustment, the two lower points of attachment (22) are locked by quick fastening means. The lower points of attachment are adjustable, transversely to the vehicle, to fit all frame widths, the frame width of a vehicle varying by 100-130 mm, which the first coupling part (10) may have.

The lower point of attachment (22) has a locking device (26) which encloses the ver¬ tical shaft (18) on the first coupling part (10). The locking device (26) has a locking plunger (27) which is screwed in for locking. In the plate (15, 16) there is a recess (19) for the plunger (27), so that the coupling device and the implement will be lock¬ ed in the vertical direction.

Figs 1-3 also show how the two coupling parts (10, 20) are interconnected. First the second coupling part (20) is positioned so high that the upper point of attachment, the shaft (24), can be lowered into the recess (17) of the first coupling part (10). The lower point of attachment, the locking device (26), encloses the vertical shaft (18) of the first coupling part (10). The locking device (26) slides on the shaft (18) until the second coupling part (20) and the associated implement (6) are arranged in the upper point of attachment (11, 21). The locking plunger (27) of the locking device (26) is screwed in. The plunger (27) is now positioned in the recess (19) formed in the plate (15, 16), so that the implement (6) is not unhooked from the upper point of attachment ( 11 ) in operation.

Figs 4a-b show a second embodiment of the second coupling part (20). The coupling part (20) comprises a device (30) for adjusting the angle (a). This is used when an angular adjustment of the implement (6) to the vehicle (2) has to be made. The imple- ments that require an angular adjustment in relation to the vehicle are the implements that extend far behind the vehicle, and should have a certain distance to the roadway. Such an implement is, for example, a truck mounted attenuator. The adjusting device (30) comprises a hinge (31) arranged in the lower part of the end plates (23), and a longitudinally adjustable part (32) arranged between the implement attachment (28) and a point in the upper part of the end plates (23). Adjustment func- tions in such a manner that when the longitudinally adjustable part (32) is extended, the angle (a) increases, and when the longitudinally adjustable part (32) is shortened, the angle (a) decreases. In the embodiment, the longitudinally adjustable part is shown as a turnbuclde (32) on each side of the second coupling part (20).

The implement (6) is mounted on the second coupling part (20) by means of the implement attachment (28) and some kind of joint, for instance screw joint or welded joint. Figs 5-9 show examples of different types of implements that can be connected to the coupling device. Figs 5-6 show a truck-mounted attenuator (40) with an angle- adjusting device according to the second, embodiment. Fig. 7 shows equipment for installing of snow posts (41), Fig. 8 an S bar (42), and Fig. 9 a traffic routing sign (43) connected to the implement attachment (28).

The coupling device (1) comprises a first coupling part (10) connected to the vehicle, preferably to the frame side members (3^ of the vehicle, comprising an upper point of attachment (11) and a lower point of attachment (12), and a second coupling part (20) connected to the implement (6), comprising a corresponding upper point of attachment (21) and a corresponding lower point of attachment (22). The coupling device comprises a first coupling part (1 O) comprising a first part (30) attached to a first frame side member (3) and a second, part (14) attached to a second frame side member (3). Both parts (13, 14) comprise an upper point of attachment (11) having a recess (17), and a lower point of attachirxent (12) having a vertical shaft (18). The first part (13) comprises a plate (15) with an upper point of attachment (11) having a recess (17) for receiving a corresponding shaft (24) of the second coupling part (20). The second part (14) comprises a second, plate (16) with an upper point of attachment (11) having a recess (17) for receiving a corresponding shaft (24) of the second coupling part (20). The recess (17) is in the form of a semicircle which is open upwards. The first part (13) and/or the second part (14) comprise a plate (15, 16) with a lower point of attachment (20) comprising a device, having a vertical shaft (18), for receiving a locking device (26) of the second coupling part (20). The plate (15, 16) comprises a recess (19) for holding the coupling parts (10, 20) locked to each other in the vertical direction (v). The upper poirxt of attachment (11) of the first coupling part (10) can be arranged in front of the rear end of the frame side members (3). The lower point of attachment (12) of the first coupling part (10) can be arranged behind the frame side members (3). Both parts (13, 14) comprise fixing devices (4) for the respective frame side members (3). The first coupling part (10) comprises two sepa¬ rate parts (13, 14) arranged one on each side of the hitch (5) of the vehicle. The coupling part (10, 20) comprises an upper point of attachment (11, 21) for load take- up in the vertical direction, and a lower point of attachment (12, 22) arranged to lock the coupling device (1) in the vertical direction. The coupling part (20) comprises two end plates (23) between which a shaft (24) is arranged as an upper point of attach¬ ment (21), a beam (25) on which a lower point of attachment (22) is horizontally adjustable, and a fixing device (28) for an implement (6) or the like. The coupling part (20) comprises a device (30) for adjusting the angle (a) between the implement (6) and the vehicle (2). The device (30) comprises a hinge (31) arranged in the lower part of the end plate and a longitudinally adjustable part (32) arranged between the fixing device (28) and a point in the upper part of the end plate. When the longitu- dinally adjustable part (32) is extended, the angle (a) increases, and when the longitu¬ dinally adjustable part (32) is shortened, the angle (a) decreases. The longitudinally adjustable part (32) comprises a turnbuckle (32). A truck mounted attenuator (40), equipment for installing of snow posts (41), a hose reel, an S bar (42) or a traffic rout¬ ing sign (43) can be connected to the fixing device (28).

The coupling device can be used as an attachment for a collision barrier, such as a Truck Mounted Attenuator, TMA, which requires special transmission of forces that is not required for other implements. The coupling can, however, advantageously also be used for other types of implements, such as post installing devices, hose reels etc.

Each make of impact-attenuator has its own solution as regards attachment/connection to the vehicle frame. In the United States, protecting vehicles with a permanently mounted impact-attenuator are often used. This is an expensive solution and is not suitable in Sweden and other countries in which much of the roadwork is carried out on contract by a plurality of, often small, contractors. Therefore a more flexible solution is required, in which a vehicle can quickly fetch an impact-attenuator and mount it in a few minutes.

A drawback of prior-art attachments of the type VV85 is that they are not very good at transmitting great horizontal forces through the attachment and into the vehicle. This type of forces arises, for example, when the implement is a shock absorber/impact-attenuator in which case some of the collision force usually proceeds into the frame structure of the vehicle. To manage this, the coupling device should be dimensioned to cope with the torques and forces arising in a collision, as is the coupling device according to the invention.