EP0587175B1 - Snow-plough - Google Patents

Abstract

A snow-plough, which is improved in practice, having a plough blade adjustable for left or right clearing and having an automatic centre alignment for obtaining an at least substantially symmetrical clearing position relative to the utility vehicle carrying it, comprises a connecting-rod arrangement (5) with connecting rods (13; 13', 13'') pivotable from the left to the right. The connecting rods (13; 13', 13'') are also additionally pivotable via axes (17; 21) aligned horizontally in each case. By way of a lifting device (33), the connecting rods can thus be pivoted about their trailing articulation points (37), which are not adjustable in height, and the plough blade (1') can then be lifted and lowered. <IMAGE>

Description

The invention relates to a snow plow according to the preamble of claim 1.

A generic snow plow with a clearing coulter that can be adjusted for left or right clearing has become known from DEC3-20 42 926. The pivotable clearing coulter, which can be adjusted to the left or right, is pivoted between the left and right clearing positions via a trapezoidal handle arrangement in plan view. The distance between the vertical axes at the leading ends of the links that support the ploughshare is smaller than the distance between the trailing pivot axes, which are also vertically aligned.

The otherwise rigid and horizontally aligned links can be adjusted in height along the rear vertical pivoting axes by means of a lifting device comprising a vertically aligned lifting cylinder.

The rear articulation axes here have the function of a slide guide, along which the handlebar arrangements that advance horizontally forward can be moved between a raised and a lowered position.

The known snow plow has the advantage due to this design feature that regardless of the clearing position to the left or right, the ploughshare comes to lie essentially in the center of the vehicle width, so that no one-sided side projection is formed. This has advantages especially when clearing roads in urban areas, where the transverse dimensions of a snow plow pivoted to the left or right should correspond approximately to the width of the vehicle. If the ploughshare were not aligned in their central position with respect to the vehicle's center of symmetry level, there would be a risk with such a narrow snow plow that it protrudes unilaterally beyond the side boundary of the vehicle carrying it and that no overlap with the following vehicle wheels is guaranteed on the opposite side , with the result that there is no snow removal here.

In order to ensure an at least largely symmetrical alignment of the ploughshare regardless of the inclination of the ploughshare, it is proposed in DE-C2-36 43 080 that the ploughshare can be adjusted via a horizontal slide guide running in the transverse direction. This carriage, which is adjustable in the transverse direction and carries the ploughshare, is then raised and lowered via a further hydraulic lifting device on the vehicle in the manner of a further vertical carriage guide.

The design effort is remarkable, however, especially in the case of the last-mentioned solution.

It also takes up an enormous installation space that extends across the front of the vehicle and is particularly susceptible to faults, particularly with regard to the two slide arrangements that can be moved horizontally and once vertically.

A device for the adjustable attachment of a dozer blade to a vehicle is also known from CH-A5-665 237.

This dozer blade suspension contains four double-acting hydraulic cylinder piston units and a linkage that holds the dozer blade at three points and connects it to the vehicle chassis. These two rods, which converge in a V-shape from the support frame to the front and are brought together at a connection point, define a vertical swivel axis around which the clearing blade can be adjusted from left to right. In addition, the entire boom and thus the ploughshare can be raised and lowered. A lateral pivoting from a broaching position on the left into a broaching position on the right under a side pivoting of the handlebars as a whole is not provided.

A snow plow has also become known from DE-A1-40 22 683. The ploughshare can be adjusted from its position to the left to the right and vice versa via a leading vertical swivel axis. Depending on the pivoting position, the lateral protrusion of the ploughshare over the vehicle on its left or right side can vary in size. A pivoting of the suspension device carrying the ploughshare to compensate for a lateral protrusion of the ploughshare on left or. There is no provision for eviction.

For lifting and lowering, this known snow plow requires a handlebar parallelogram with ball joints is suspended as a pivot bearing. Ball joints are fragile and expensive. In order to absorb the lateral forces, this snow plow also requires additional triangular links in one of the two swiveling planes of the link parallelogram or in a plane parallel to it. This overall structure makes the plow overall bulky, heavy and comparatively expensive.

The snow plow known from DE-A1-26 28 108 also has a parallelogram handlebar suspension, which can be raised and lowered using a lifting / lowering cylinder. In order to enable different driving and clearing situations, the handlebars, which enable lifting and lowering, are telescopic. Side pivoting is secured by inclined or diagonal stabilizer arms. A lateral pivoting of the parallelogram handlebar arrangement to compensate for a lateral offset when clearing to the left or to the right is therefore not provided. Nevertheless, all joints of the telescopic handlebars should consist of expensive and comparatively fragile ball joints.

The snow plow known from EP-B1-0 063 212 has a vertical pivot axis which cannot be pivoted when swiveling from the left to the right, which is held fixed by a handlebar arrangement which runs towards one another in a triangular shape from the support frame. Depending on the left or right evacuation, this results in a differently large undesired lateral protrusion of the ploughshare.

There is a need for an upper and lower pair of hydraulically actuated swivel cylinders, either at their leading and trailing ends around a horizontal axis or, in the case of the lower pair of swiveling cylinders, at their rear ends around a horizontal and at their leading articulation ends are suspended on the ploughshare so as to be pivotable about a vertical axis. Since when pivoting from left to right, and vice versa, the pivoting cylinder must undergo a slight lateral pivoting movement, the suspension at the pivot points allowing pivoting about an axis is necessary and necessary.

The object of the present invention is to create an improved snow plow based on the prior art mentioned at the outset, which, regardless of its pivoting position in right or left-hand clearance, is at least largely or approximately adjustable in its symmetrical central position with respect to the longitudinal axis of the vehicle, and which is constructive in the process is simple and less prone to failure.

The object is achieved according to the features specified in the characterizing part of claim 1. Advantageous embodiments of the invention are specified in the subclaims.

The snow plow according to the invention is distinguished on the one hand by the fact that the handlebar arrangement which allows pivoting between the left and right clearing positions can also be raised or lowered downward via a rear horizontal axis between an upper and lower pivoting position. On the one hand, this is much easier to implement in terms of construction and, above all, much less prone to failure.

In addition, an intermediate frame can be provided on the ploughshare side, on which the actual ploughshare is then suspended. But it is also possible that the ploughshare is suspended on the handlebar arrangement without a special intermediate frame, and with a different type of evasive device is provided; this can consist, for example, in the form of a scraper bar which can be folded away to the rear relative to the remaining ploughshare elements.

Compared to DE-C3-20 42 926 it is also provided that the ploughshare suspended over the intermediate frame is provided with a separate evasive device which allows the ploughshare to evade relative to the intermediate frame when approaching a ground obstacle. The evasive device can, for example, correspond in principle to the suspension and evasive device according to DE-AS-12 78 465. However, other embodiments are also possible.

In particular the connection of the handlebars, i.e. the linkage of the handlebars on the ploughshare or on the intermediate frame carrying the ploughshare and on the vehicle side on the support frame takes place with sufficient play. This offers a decisive advantage. The suspension that permits play ensures that, due to this tolerance, the ploughshare can be pivoted and tilted to a sufficient extent to a tilting axis lying in the direction of travel. If, for example, the vehicle turns slightly to the left and the road surface, on the other hand, slopes more to the right, the ploughshare can perform a relative pivoting, deviating from the vehicle inclination, that is also deviating from the horizontal plane. In this respect, complex tilting or pivoting mechanisms are no longer necessary.

Finally, the universal or cardanic joints used at least for the handlebars carrying the ploughshare require hardly any maintenance and care compared to other joints, such as ball joints, because of their extremely robust design, and they are also inexpensively available. Through this by means of the cross or Cardanic joints with play articulated handlebars allow the desired tilting movement about an imaginary, essentially horizontal axis line running in the direction of travel to any sufficient extent without any restriction.

The articulation of the other handlebars used to adjust the ploughshare, i.e. the swivel cylinder as well as the lifting device, which is preferably in the form of a lifting cylinder, can be designed at the corresponding articulation points on the ploughshare and support frame side without play or without substantial play. Because such cylinders are inevitably formed with the formation of a swivel cylinder housing and a housing axially displaceably guided therein, a relative rotation between the piston and swivel cylinder is always possible. These joints for this pivoting handlebar could also consist of spherical joints.

Finally, however, all articulated connection points, that is to say in particular also the articulation points of the pivoting cylinders and / or the lifting device, which is preferably in the form of a lifting cylinder, can take place at the respective connection points by means of universal or cardanic joints.

An embodiment with a handlebar arrangement comprising only three handlebars has proven to be particularly favorable. This ensures a three-point suspension of the intermediate frame compared to the vehicle-side support frame.

Figur 1 :

eine schematische ausschnittsweise Draufsicht auf den erfindungsgemäßen Schneepflug mit fahrzeugseitigem Tragrahmen oder fahrzeugseitiger Tragplatte;

Figur 2 :

eine schematische Seitenansicht quer zur Fahr- und Räumrichtung bei in Räumstellung abgesenkter Pflugschar;

Figur 3 :

eine auszugsweise seitliche Darstellung des in gegenüber dem fahrzeugseitigen Tragrahmen in Hubstellung angehobenen Zwischenrahmens ohne weiterer im Detail dargestellter Pflugschar.

Further advantages, details and features of the invention result from the exemplary embodiment shown in the drawings. The individual shows:

Figure 1:

a schematic partial plan view of the snow plow according to the invention with a vehicle-side support frame or vehicle-side support plate;

Figure 2:

a schematic side view transverse to the direction of travel and clearing with the ploughshare lowered in the clearing position;

Figure 3:

a partial side view of the raised in the lifting position in relation to the vehicle-side support frame in the intermediate frame without further ploughshare shown in detail.

In Figure 1 is a schematic plan view of the snow plow with a ploughshare 1, a vehicle-side support frame 3, d. H. a vehicle-side device plate 3, as well as a handlebar arrangement 5, which includes, among other things, a V-shaped top view in the direction of travel between the support frame 3 and the ploughshare 1 or, in the exemplary embodiment shown, an intermediate frame 9 carrying the ploughshare 1, diverging pivoting cylinder 7.

The individual ploughshare segments are suspended from the intermediate frame 9 via upper and lower elastic bands 11. In the exemplary embodiment shown, three ploughshare segments 1 'which are independent of one another and laterally offset from one another are shown and are suspended above the upper and lower elastic bands 11 each facing their end region. When approaching a ground obstacle, the elastic bands can yield, the lower elastic bands 11 being compressed in an S-shape and at the same time being adjusted upwards, so that the plowshare segment 1 'in question approaching a ground obstacle is raised and in a side view is rotated counterclockwise according to Figure 2.

In the exemplary embodiment shown, the intermediate frame 9 is held and guided with the vehicle-side support frame 3 via three links 13. The three links 13 can each be pivoted via a vertical axis 15 on the vehicle side and, in addition, via a further horizontal axis 17.

The articulation points of the links 13 on the intermediate frame 9 are likewise realized by means of vertical and horizontal axes 19 and 21, which are coupled to one another.

These articulation points can preferably consist of a universal or gimbal joint in order to be able to pivot in the two degrees of freedom mentioned.

The lifting and lowering movement is accomplished by means of a lifting cylinder 23 which, in the exemplary embodiment shown according to FIG. 2, is installed along the dash-dotted line 25 shown there. In other words, the lifting cylinder 23 is supported on the vehicle side at a lower support point 27, which is located centrally in the plan view, and on the ploughshare side on a support point 29 which is higher than this, which in the exemplary embodiment shown is formed on a flange attachment 31 attached to the underside of the upper link 13 '.

The two swivel cylinders 7 are supported on the vehicle side at two relatively closely spaced support points 33, that is to say articulation points 33 and at their leading end on the intermediate frame 9 at two support points lying further outwards, ie articulation points 35. The swivel cylinders 7 can be telescopically extended and retracted. It is shown in Figure 2 that the trailing articulation points 33 and 35 leading the articulation points Swivel cylinders 7 are preferably formed from a cross or cardan joint in order to enable pivoting about a horizontal and a vertical axis at each of their articulation points.

As can be seen from Figures 2 and 3, their orientation in the side view is approximately parallel to the handlebars 13 'and 13 ".

In the embodiment, three links 13 are used. The two lower links 13 "run together in the direction of travel and clearing with the ploughshare 1 'aligned perpendicular to the direction of travel, are of equal length, in their neutral starting position with the ploughshare aligned horizontally at their leading and rear ends, each articulated at the same height (where depending on the clearing or inoperative position, the leading articulation points are then lower or higher than the trailing articulation points), the distance between the two rear articulation points, i.e. articulation points 37, being very much greater than the distance between the leading articulation points, i.e. articulation points 39 (FIG. 1 ).

The third overhead link 13 'is articulated centrally on the vehicle-side support frame 3 as well as on its leading end on the intermediate frame 9 in a top view. This offers the advantage that the lifting cylinder 23 already mentioned can be arranged in a vertical plane below this third link 13 'above, without this colliding with the other links or the pivot cylinders. The lifting cylinder 23 is supported and articulated at its leading end on a flange shoulder 31 connected to the upper link 13 'via a horizontal axis 31' formed there and at its trailing end preferably via a cardan or universal joint on the support frame 3.

The kinematics ensure that the ploughshare aligned to the left, as shown in Figure 1, is automatically shifted to the right to such an extent that the area of the scraper edge preferably lies approximately in the symmetrical longitudinal plane of the vehicle and when pivoting to achieve a Clearance is pivoted accordingly in the opposite direction.

Finally, the handlebars 13 'and 13 "are connected in the area of their leading and trailing articulation points with play to the ploughshare 1 or the intermediate frame 9 carrying the ploughshare 1, but also to the support frame 3. The game is chosen so that a sufficient tilting movement the ploughshare 1 is possible transversely to the carriageway or direction of travel (that is to say about an imaginary and essentially horizontal axis of tilt) without the need for complex further pivoting or tilting mechanisms. The play selected also restricts the amount of tilting movement With simple means, a favorable roadway compensation is made possible.

Deviating from the exemplary embodiment shown, a link arrangement 5 is also conceivable which has two upper links, likewise arranged in a trapezoidal shape, with respect to the single overhead link 13 ′.

In a departure from the exemplary embodiment shown, the ploughshare 1 could also be suspended and held directly on the links 13 and adjustable via the swivel cylinder 7. A different type of evasive device can then be provided on the ploughshare or the ploughshare segments. This can consist, for example, of a scraper bar which can be folded away when approaching a ground obstacle, over which the ploughshare, in case of a collision with a Ground obstacle, at least raised to a certain extent, wherein the evasive movement can be made possible and supported by the mentioned handlebars.

Claims (9)

1. A snow plow for front mounting on a road vehicle, comprising a plow share (1) able to be set for snow clearing on the left or right side and held by pivotal links (13; 13', 13") able to be pivoted from the left to the right and vice versa on a support frame (3) on the vehicle, such links (13; 13', 13") being able to be laterally pivoted at their leading and trailing pivot points respectively using vertically aligned pivot shafts (15 and 19) by means of a pivotal cylinder arrangement (3) acting at least indirectly between the plow share (1) and the support frame (3) on the vehicle and by means of a reciprocating cylinder arrangement are able to be lifted and lowered, the transverse spacing of the trailing vertical pivot shafts (15) on the vehicle of two links (13' and 13") being greater than the lateral spacing between leading vertical pivot shafts (19) on the plow share, of the links (13") and furthermore at least one third link (13') which is offset in height in relation to the other two links (13"), characterized in that the links (13; 13' and 13") at their trailing and also their leading pivot points are able to be additionally pivoted respectively using a horizontal pivot shaft (17; 21), transverse or universal joints being provided at the leading and the trailing pivot points of the pivotal links (13; 13' and 13"), by means of which even in the case of trailing pivot points able to be adjusted in height on the support frame (3) by means of the reciprocating cylinder arrangement (23) the leading pivot points and accordingly the plow share (1) is able to be adjusted in height, in that the reciprocating cylinder arrangement (23) and the pivot cylinder arrangement (7) are so supported on their leading and trailing ends that they can cause a pivot movement of the plow share (1) from the left to the right and vice versa and in the lifting and lowering direction with the leading ends following said movements, and in that the links (13; 13' and 13") are mounted and held at their leading and/or trailing pivot points with play and in that furthermore a yielding device is provided for the plow share (1) effective on meeting with an obstruction on the ground to allow a yielding movement thereof.
2. The snow plow as claimed in claim 1, characterized in that between the plow share (1) and the leading pivot points of the links (13; 13' and 13") an intermediate frame (9) is provided which is connected with the leading ends of the links (13) and using the pivot shaft (19 and 21) permitting a pivoting movement about vertical and also horizontal pivot shaft (19 and 21) and in that the plow share (1) is mounted on the intermediate frame using the yielding means.
3. The snow plow as claimed in claim 1 or in claim 2, characterized by two pivot cylinders (7) diverging apart as seen in plan view from the support arrangement (3) toward the plow share (1) which cylinders are support at their trailing and at their leading ends using a transverse or universal joint.
4. The snow plow as claimed in any one of the claims 1 through 3, characterized in that the plow share (1) or, respectively, the intermediate frame (9) bearing the plow share (1) is carried and supported by means of a three point linkage, two links (13") being arranged in a lower position whereas the third link (13') is arranged as seen in plan view in a position which is central in relation to the two other links (13").
5. The snow plow as claimed in any one of the claims 1 through 4, characterized in that as a reciprocating cylinder arrangement a reciprocating cylinder is provided which is in a common vertical plane with the preferably single upper link or one of the upper links 13').
6. The snow plow as claimed in claim 5, characterized in that the reciprocating cylinder (23) bears in an articulated fashion at one end on the link (13').
7. The snow plow as claimed in claim 6, characterized in that the reciprocating cylinder (23) has its leading end supported on the link (13') by means of a horizontal shaft(31).
8. The snow plow as claimed in any one of the claims 5 through 7 characterized in that the reciprocating cylinder (23) is supported at its trailing end by means of a transverse or universal joint.
9. The snow plow as claimed in any one of the claims 1 through 3 or 5 through 8, characterized in that an upper and a lower pair of links (13' and 13") is provided.

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