Wheel-borne loading machines are common in the market. These machines as a rule have a loading unit provided with hydraulic cylinders and comprising for instance forks or a bucket, by means of which it is possible to load or unload goo and to move goods between two points. In the later case this "transport of gooαs may involve transportation a long distance along a bumpy road. Therewith there arise strong swingings in the machine if this one snould drive into a pit. These swing- ings oecome stronger if the loading unit carries a load of an kind. Since the lifting cylinders of the loading unit during transportation on a road are locked in a certain position, there arise strong loads on the loading unit when the machine drives into a pit, which loads are directly transmitted to th chassis of the loading machine and therefrom to the wheels of the loading machine. The result will be a very bad riding com fort for the driver of the loading machine, strains on the loading machine and its loading unit and large stresses on th tyres of the loading machine. Thus, when the driver of the machine happens to drive into a pit with the result that the machine comes into swingings _f he must immediately reduce the velocity strongly in order that the swinging shall be reduced This invention intends to remove the problems with know technique. This has been made possible by a device of the kin mentioned by way of introduction, which is characterized in that it is intended to cooperate with the loading unit in suc a way that the movements of swinging of the machine are dampe and that the device is connected with the hydraulic system of the machine. Due to that fact the uncomfortable movements of swinging of the machine are substantially eliminated, whereby the comfort for the driver increases and the stresses on the machine and on the loading unit are reduced. Moreover, the life-length of the tyres increases evidently. The remaining features of the invention will appear more closely below.

A preferred embodiment of the invention shall be de¬ scribed more closely with reference to the accompanying draw¬ ings, where Pier. 1 shows a connection diagram for a hydraulic system in an existing loading machine _r - Fig. 2 shows a connce- tion diagram for a device according to the invention in that moment when an extra load is applied onto the loading unit of loading machine; Fig. 3 shows the connection diagram according to Fig. 2 in the moment afterwards and Pier. 4 shows an electri cally controlled magnetic valve for regulation of the device according to the invention.

Referring to Fig. 1 is there shown a connection diagram for a hydraulic system in a loading machine being in the market. Therewith two hydraulic cylinders 1, 2 are shown, whic are used as lifting cylinders for the loading unit of the load ing machine. These hydraulic cylinders have connection with a direction valve .

The device according to the invention for dampening movements of swinging of the loading machine is intended to be able to be arranged in the hydraulic system of both new and existing loading machines. Therewith the device is connected with the hydraulic system between the hydraulic cylinders 1, 2 and the direction valve 3. The device according to the inven¬ tion is intended to admit a certain damped movement of the loading unit in relation to the chassis of the loading machin when the machine transports goods on a road. Thus, the loadin unit is not locked in a certain position during transportatio as in conventional loading machines. This movement of the loa ing unit in relation to the chassis of the loading machine is accordingly achieved by means of the device shown in Figs. 2- The device comprises a conduit 4A. B, which is connected to the pressure side of the hydraulic cylinders 1, This conduit is via a non-return valve 5 connected to an accu mulator 6 which may comprise a membrane pressure chamber or a cylinder in which a plunger is movably arranged. Therewith th cylinder is closed so that there is a space in front of and behind, respectively, the plunger. In the space in front of t plunger hydraulic oil is intended to be pressed into and out the cylinder, while a gas, preferably nitrogen gas, is intend to be compressed and to expand, respectively, in the space be

hind the plunger. At the non-return valve 5 there is arranged by-pass conduit 7 in which a throttle valve 6 is arranged. Th valve is adjustable with regard to operation conditions and type of loading machine. Tne device further comprises a condu 9A, B, which is connected to the suction side of the hydrauli cylinders 1. 2, and which has connection with the hydraulic tank 10 of the hydraulic system.

In Fig. 2 is shown what is happening if there araises a extra load on the loading unit of a loading machine, provided with goods, for instance if the loading macnine drives into a pit when driving on a road. Therewith the loading unit is temporarily lowered which has the consequence that the plunge 11 is pressed further into the cylinder house 12 of the hydra lic cylinders l, 2 resulting in that hydraulic oil is pressed via the conduit 4A. B and the non-return valve 5 into the accumulator 6 in the space in front of the plunger or the membrane, whereby the pressure increases in the accumulator behind the membrane or the plunger. At the same time hydrauli oil is sucked from the hydraulic tank 10 via the conduit 9A, into the hydraulic cylinders l , 2 on the rear side of the plunger 11. In the next moment, that is when the extra load h temporarily ceased on the loading unit of the loading machine, oil is pressed back from the accumulator 6 via the throttle valve 8 and the conduit 4A. B to the hydraulic cylinders 1, 2. which has the consequence that the plunger 11 is pressed back in the cylinder 12 resulting in that the loading unit of the loading machine is raised to its normal position. Since hydra lic oil in the former moment is sucked into the rear side of the plunger 11, this movement backwards is made against the pressure of the oil being behind the plunger 11. which is accordingly pressed back to the hydraulic oil tank 10 via the conduit 9A, B. Therefore the movement backwards of the plunger 11 is made by a reduced velocity, which has the consequence that the raising of the loading unit of the loading machine is made softly and smoothly. Due to that fact the swinging of the machine immediately ceases after the machine has been drived into a pit.

In Fig. 4 is shown a further developed device according to the present invention. This device comprises an electricall

controlled magnetic valve 13 for connecting the dampening de¬ vice and disconnecting the same, because this one needs not to be connected during loading and unloading of goods but pre¬ ferably only when driving the loading machine on a road with a load on the loading unit.

In Figs. 2 and 3 is accordingly shown the magnet valve 1 in position II which applies when the dampening device Is connected. Therewith the conduit 4A, which extends from the pressure side of the hydraulic cylinders l, 2 to the magnet valve 13, is via this one connected with the line 4B, which extends from the magnet valve to the accumulator 6, while the conduit 9A, which extends from the suction side of the hydrau¬ lic cylinders to the magnet valve 13, via this one is connecte with .the conduit 9B, which extends from the magnet valve 13 to the hydraulic oil tank 10.

If the driver of the machine now wants to disconnect the dampening device, he pushes a button in the machine, whereby the electrically controlled magnet valve 13 takes the position I, see Fig. 4. Therewith the connection between the conduits 4 and 4B on one hand and between 9A and 9B on the other hand is broken, whereby the loading machine provided with the device patent applied for functions as a conventional loading machine If there is a desire again to connect the dampening device, th button is again pushed in, whereby the magnet valve takes the position II.

In the application wheel-borne loading machines have bee described. Of course, the invention can be applied onto other types of loading machines and loading cranes.