Snowplough with adjustable blade

The present invention relates to a snow plow provided with a device for preventing damage to the plow blade in the event of a collision with fixed obstacles, the plow blade possibly being laterally divided into several parts and being connected to a support device via link arms and spring elements.

It is previously known that in the case of snow plows, the plow blade is applied to the upper and lower link arms, so that when an obstacle is hit, it can fold backwards and upwards with its lower edge. For this purpose, the lower link arms, which start from a support device, are arranged obliquely upwards in the direction of the plow blade. The plow blade is then pressed by means of spring force in the direction of the roadway. Admittedly, such a device enables a good adaptation of the plow blade to the road surface and allows minor obstacles to be run over without damaging the snow plow. However, when hitting larger obstacles, for example curbs, the folding space on such a device is not sufficient to enable the plow blade to slide over the obstacle. In addition, in the case of larger obstacles with approximately vertical edges, a considerable friction also arises between the lower edge of the plow blade and the obstacle, which causes great stresses on the suspension of the plow blade, so that the plow blade itself or its support device can be damaged.

In order to protect the snow plow from damage by major ground obstacles, it is previously known to place the plow blade pivotally about a horizontal axis behind it on its support device. During normal operation, this pivoting possibility is blocked by means of a cutting bolt or the like. When an obstacle is encountered, the plow blade is swung, so that its lower edge can easily fold away even for a larger obstacle. Such an arrangement of the plow blade on a snow plow does protect it from damage, but does not allow a continuous adaptation to the roadway during snow removal. On the other hand, after the criminal protection has worked, it is necessary to interrupt the clearing work in order to return the plow blade, which has been turned over due to the obstacle, to the normal position and lock it there.

The object of the present invention is to produce a snow plow, the plow blade of which continuously adapts to the roadway and can fold away in the case of minor obstacles without interruption in the clearing work, and yet also in the case of larger obstacles with a relatively steep impact surface to prevent damage to the snow plow.

The snow plow according to the invention has been given the design and obtained the characteristics which appear from the appended claims.

The invention is clarified by the accompanying drawings, in which:

Fig. 1 shows an embodiment of a snow plow according to the invention in side view in normal position,

Fig. 2 shows the same snow plow as Fig. 1, with a plow blade present in the upper abutment position,

Fig. 3 shows another embodiment of a snow plow according to the invention with a plow blade divided laterally into several parts, with a side part twisted due to a higher obstacle, and

Fig. 4 shows a plan view of a plow blade divided into several side parts and with a twisted end part.

Fig. 1 shows a snow plow, with a plow blade 1, which via link arms 2 and is connected to a support device 4. The support device 4 is rotatably mounted on a horizontally running shaft 5. The shaft 5 is in turn rigidly connected to a fastening device 6. The link arm 3 runs obliquely upwards from the support device 4 towards the plow blade 1, so that the plow blade, when its lower edge meets an obstacle, can be moved upwards against the force of a spring 7. The size of this movement is limited by stops 8 and 9, between which a nose 10 fixedly connected to the shaft 5 is located. In the normal position shown in Fig. 1, the upper stop 8 lies on top of the nose 10.

Fig. 2 shows the same snow plow as Fig. 1 and the same designation numbers for the same parts have been used. However, the plow blade 1 is located on top of an obstacle 11, so that the link arms 2 and 3 together with the plow blade 1 have been pivoted upwards. In this position, the lower stop 9 abuts the nose 10 from below.

Fig. 3 shows a snow plow, whose plow blade 1, 1a, is laterally divided into several, mutually separated, separately moving parts. The shaft 5 common to the different parts is rigidly connected, to the fastening device 6, which is connected via support arms 12 and 13 and a lifting device 14 to a support plate 15 on a vehicle. The nearest plow blade 1 has been rotated forward about the shaft 5 by a higher obstacle 16, for which the plow blade 1 could not fold away by means of the link arms 2 and 3 ·

Fig. 4 shows a plan view of a snow plow, the plow blade of which is divided into several parts 1a, 1b, 1c, 1d, all of which are connected to the shaft 5, which in turn is connected via a fastening device · 6 to the support arm 12, The right plow blade 1 has been brought to the turned position of the obstacle 16.

The plow blade 1 of a snow plow according to the present invention can via its link arms 2,3 continuously fold away for road surface irregularities and minor obstacles, after which the plow blade 1 as soon as it has slipped over an obstacle returns to its original position. However, the plow blade 1 arranged according to the present invention can also fold away for major obstacles by a twisting, so that damage to the plow blade 1 or its support device is certainly prevented.

If the plow blade as in Figs. individual support devices arranged for the plow blade parts can be rotatable independently of each other about the axis 5 carrying the individual support devices. Such a split plow blade allows a particularly good adaptation to the carriageway intended for snow removal. When larger obstacles, such as paving stones or the like, have been found in practice to be present only in the vicinity of the edge of a carriageway, even with a laterally divided plow blade, only the two end parts can be applied to a support device pivotable about the axis 5. The support device for the middle parts of the plow blade can be rigidly connected to the shaft 5, since one does not usually expect major obstacles in their clearing area. It is enough here with the possibility given via the link arms for the plow blade parts to fold away.