US 3429059 A
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1969 G. REISSINGER CLEARING BLADE FOR SNOWPLOWS Filed Aug. 6, 1965 United States Patent ABSTRACT OF THE DISCLOSURE A clearing device for attachment to a snowplow which comprises a clearing blade having a forwardly directed front surface, and a support carrying the blade. A roll sector is pivotally secured to the support and has a front face. Spring suspension means are disposed between the support and the roll sector, in order to permit a swinging movement of the roll sector. The latter has in its normal position the upper end of its front face adjacent the lower end of the clearing blade. A clearing strip is pivotally connected to the lower end of the front face of the roll sector. Limiting means are secured to the bottom of the roll sector which limits the swinging movement of the clearing strip by engagement of the latter with the limiting means.
The present invention relates to a clearing blade for snowplows with a clearing strip being pivoted beneath the edge of the clearing blade and giving way resiliently at impediments.
With clearing blades of the known kind, e.g. the pivoted clearing strip turns backwards impinging onto an impediment against the resistance of shearing bolts or strong springs. This requires, that the clearing strip is approximately vertical, in order that it gives way backwardly without an excessively strong vertical movement of the whole plow. However, a clearing strip being that steep has to be pressed continuously with high pressure onto the roadway, if a satisfactory effect of clearing is desired.
For this reason the clearing strip has to be pivoted to a plow blade in such manner, that is forms an acute angle in the direction of the clearing. When impinging upon an impediment, it gives way at first upwardly and then backwardly, if it is connected to the clearing blade by way of parallelogram guide rods cooperating with springs and shearing bolts. However, at a quick clearing the suddenly occurring resistance of an impediment is too large, so that damages of the roadway of the plow happen frequently, as at first the shearing bolts have to be knocked off.
A clearing strip is known, too, which is pivoted by way of a spring loaded hinge joint to a connecting bar cooperating with a stop at the clearing blade, whereby the two strips are arranged in such manner, that their back faces form an obtuse angle in the normal position of the clearing blade and that one or more tightenable springs are connected to the connecting strip by way of at least one lever attached thereto. This solution has the advantage, that the clearing strip, being arranged at an acute angle towards the front removes the snow in a very good manner from the road. However, there is the disadvantage, that the clearing strip and the connecting strip enlarge the distance to the clearing blade, so that the snow taken up remains lying in a trough.
It is one object of the present invention to provide a clearing blade for snowplows, wherein the connecting strip is displaced behind the blade, so that'no dead room is formed in the blade trough, as the snow is directed upwards immediately behind the clearing strip. A roll sector is attached to the connecting strip, which closes the lower edge of the clearing blade with respect to the clearing strip.
With this and other objects in view which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawing, in which:
FIGURE 1 is an elevation, partly in section, of a clearing blade in cleaning position; and FIG. 2 is a similar elevation of the clearing strip giving way to an impediment.
Referring now to the drawing, a clearing blade 1 is in known manner attached in front of a clearing vehicle and can be lifted and lowered and even pivoted transversely to the driving direction. A clearing strip 2 is connected to a spring loaded hinge joint 4 by means of a clamping device 3. A roll sector 7 includes a limitation means 8 in the form of an inwardly directed abutment for limiting the turning of the clearing strip 2 as shown in FIG. 2. The roll sector 7 is pivoted in a U-shaped member 6 by means of a tube 5 welded thereto. Spring elements 10, which also could cooperate with shock absorbers (not shown) are movably screwed in the spring suspensions 9 and 11. A support 12 provides an abutment for the spring means 10. A sickle-shaped stiffening device 13 serves, as usual, for the reinforcement of the blade -1.
The roll sector 7 being disposed below the lower edge of the blade 1, closes the space between the lower edge of the blade 1 and the clearing strip 2 in each position of the clearing strip 2. In FIG. 2 the clearing strip 2 is shown at the passage over an impediment 1'. The roll sector 7 is thereby pressed upwards by the clearing strip 2, which turns upwards and is raised before the impedi lment from its position, i.e. inclined towards the front. The spring elements 10 effect thereby an adjustable, i.e. variable resistance. They press the roll sector 7 again into the normal position according to FIG. 1, after a short lift of the blade 1 by its lifting device and the turning of the clearing strip 2 made possible thereby.
The roll sector 7 has a further function. The quantities of snow taken up by the clearing strip 2 slide upwards thereon and are not, as usual, pressed into the blade trough and come in contact with a protrusion 8 of the roll sector 7, which protrusion 8 operates as the limitation means. Thereby a change of direction of almost is achieved. The snow is thrown upwards, without being forced to slide up, the blade trough being relatively coarse. Thus, the snow is thrown a large distance, even at low speed. A short distance from the clearing strip 2 to the blade 1 and the forced change of direction of the snow at the protrusion 8 of the roll sector 7 are here cooperating.
It is advantageous to construct the roll sector 7 by screwing together steel sheets. Damages occurring in the course of utilization can therefore be repaired quite easily.
The effect of the curvature of the roll sector 7 is independent from the formation of the resilient clearing strip 2. The effect even occurs, if a snowplow of normal construction has a blade formed accordingly or an extension welded to the lower edge of the blade 1 or attached in another manner. The essential fact is, that the snow does not come into contact with the blade 1 gradually, but is thrown up abruptly and contacts thereby a part of the blade only.
The higher density of trafiic demands higher clearing speeds as in former times, if the clearing vehicle is not to be an obstacle for the flowing traflic. Raised speed causes a considerable wind pressure at the large surface of the clearing blade 1. Thus, the snow is pressed even more onto the blade trough, thus subjected to higher friction; and the throwing distance is worsened.
For avoiding these drawbacks, according to a further feature of the present invention, a wind shield is arranged in a suitable distance in front of the clearing blade 1. This shield can be extended over the complete length of the clearing blade 1 or can cover a part of the latter only, whereby its height is preferably of the height of the blade 1. The shield might have an adjusting device for the height and side position and can thus be adapted to the prevailing snow and wind conditions. FIG. 1 shows the device schematically. The locking device has a longitudinal axis 14 and has two or more holding arms 15, the form of which is designed to provide the lowest resistance with respect to the thrown out snow. A longitudinal axis 16 is spring loaded e.g. by a rubber torsion spring. The axes 14 and 16 cooperate such, that a wind shield 17 yields resiliently in vertical and horizontal direction upon engaging an impediment. Also a suspension, which is more rigid can be chosen, whereby the shield 17 is supported with respect to the clearing blade 1 at other positions several times. The shown suspension of the wind shield 17 has the purpose of, suspending the shield 17 vertically downwards, as well as of adjusting the same turned away or inclined to the blade 1. Furthermore, the wind shield 17 can be thus adjusted such, that it is in parallel with the length of the plow blade 1 or at an acute angle thereto. The wind shield 17 and the holding arms 15 are secured in any conventional manner to maintain them in any pivoted position about the axis 16 and the axis 14, respectively. If large amounts of snow are to be cleared, it is possible that the shield 17 is a drawback. In such cases it is turned upwards to the rear after loosening a lock (not shown) and forms thus an extension of the upper part of the clearing blade 1.
The Wind shield itself has a form being favourable with respect to stream conditions for the intended purpose; not only metals but also suitable plastics can be used.
While I have disclosed one embodiment of the present invention, it is to be understood that this embodiment is given by example only and not in a limiting sense.
1. In a clearing device for attachment to a snowplow vehicle, the combination which comprises:
a clearing blade having a forwardly directed front surface and having a lower end thereof,
a support carrying said blade,
a sector of a roller pivotally secured to said support at 45 a pivot connection spaced from said lower end of said clearing blade and having a front peripheral face movably disposed relative and adjacent to said lower end of said clearing blade, spring suspension means disposed between said support and said sector, in order to permit a swinging movement of said sector, the latter in its normal posi tion having the upper end of said front peripheral face adjacent said lower end of said clearing blade, and a clearing strip pivotally connected to the lower end of the front peripheral face of said sector. 2. The clearing device, as set forth in claim 1, which includes:
a wind shield pivotally secured to and extending spaced apart from, as Well as in front of said clearing blade. 3. The clearing blade, as set forth in claim 2, wherein: said wind shield is operatively suspended from and substantially parallel to said clearing blade. 4. The clearing blade, as set forth in claim 2, wherein: said wind shield is operatively suspended from and ad justably positioned with respect to said clearing blade. 5. The clearing blade, as set forth in claim 1, which includes:
a U-shaped member secured to the lower rear end of said support, and a tube secured to the rear end of said roll sector and received in said U-shaped member, in order to permit said swinging movement of said sector relative to said support. 6. The clearing device, as set forth in claim 1, further comprising:
abutment means secured to the bottom of said sector and adapted for limiting said swinging movement of said clearing strip by abutment of the latter with said abutment means.
References Cited UNITED STATES PATENTS 1,728,032 9/ 1929 Bising 3742 3,014,289 12/1961 Torrey 37-50 3,199,234 8/1965 Reissinger 37-42 FOREIGN PATENTS 313,333 5/ 1956 Switzerland.
ABRAHAM G. STONE, Primary Examiner.
ALAN E. KOPECKI, Assistant Examin'er.