Dozer blade

Abstract

Dozer blade with a central main blade (2), wherein a right and a left half-blade (3) are arranged in front of the main blade (2), which half-blades have a curvature such that they fit into the main blade (2) with their rear side essentially parallel to the contour, wherein the half-blades (3) are independently extendable laterally beyond the main blade (2), characterized by that two superimposed groove profile strips (16) are inserted closely above the cutting edge (4) and parallel to it into the front wall (6) of the main shield (2) flush with the front side of the front wall (6) of the main shield, which extend over the entire width of the main shield (2), and that slotted nut strips (17) engage in these profile strips (16), which are fastened to the rear of the half-shields and, in the retracted position of the half-shields, also extend over the entire width of the main shield (2).

Description

The invention relates to a blade with a central main blade, to which all connection points to the carrier device are also attached. Like all conventional dozer blades, the main blade has a screwed-on replaceable cutting edge at the lower edge.It is known that for producing surfaces with precise specifications such as inclination, height and flatness in the construction industry, GPS-supported dozers or motor graders are usually used and that these distribute and planinate the material as desired with a dozer blade.When producing surfaces using these machines, the width of the blade is decisive for the surface performance and quality of the finished surface, which is why blade widenings are often mounted. In order to increase the amount of material that can be moved with such a blade, additional entrainment blades are often mounted laterally. Thus, the shield has a slight U-shape and the material cannot flow out as easily laterally.The width and also the size of the driver plates is limited in most cases by the transport dimensions applicable legally. For this purpose, there are already various solutions according to which additional widenings can be set up on the blade, screwed or folded forward or backward by means of a rotary joint.Of course, there is also the solution approach that the entire sign is dismounted for transport and transported with a separate truck along the direction of travel. The mounting and dismounting of the entire shield or of the individual extension components is, however, always associated with a high expenditure of time and cost.US 2003 / 0226289 A1 discloses a blade with a central main blade, wherein a right and a left half blade are arranged in front of the main blade, which half blades have a curvature such that they fit with their rear side substantially parallel to the contour into the main blade, wherein two groove profile strips lying one above the other are inserted parallel to the cutting edge into the front wall of the main blade, and wherein sliding block strips which are fastened to the rear side of the half blades engage into these profile strips.The object of the present invention is to provide a blade with which the above-described disadvantages of the previously known solutions are avoided and the advantages of these options are nevertheless achieved.This object is achieved according to the invention by the features of claim 1.Advantageous embodiments of the invention are characterized in the dependent claims.The invention provides that a right and a left half-shield are arranged in front of the main shield, which half-shields have a curvature such that they fit with their rear side into the main shield essentially parallel to the contour, and that the half-shields can be extended independently in a continuously variable manner laterally beyond the main shield. In this case, it is preferably provided that the half-panels can be extended in each case by approximately 1 / 4 of the width of the main panel and that they are in each case approximately half as wide as the main panel.Particularly with the use of GPS control systems available on the market today and the sensitive control of construction machines of today, very precise surface characteristics can be produced. However, the critical point is always the transitions between the individual lanes. According to the present invention, it is achieved that more area can be machined in a pass through the wider blade, and thus fewer passes next to one another are also necessary. This also results in less critical transitions.When surfaces for the substructure of roads or also track bodies are produced, it may often occur that the surface to be machined varies greatly in width. This can be due to columns for overhead lines, road junctions or also the area of switches and also the station area with its platform. Especially, when the machining width is greatly reduced in a short distance and then rapidly increased again, this may become a problem because this offset can be generated only by large steering movements in the crawler type vehicles known heretofore. As is known, in track vehicles, material is pushed on during heavy manoeuvring movements by the rotation of the running belts. This pushed-on material significantly damage the finished surface. Since the half-shields can be extended continuously in the case of the blade according to the invention, a half-shield can be extended in front of an object of disturbance such as a column, can be retracted when the column is reached and can be extended back to the original width behind the column. All this is done without steering movement of the host vehicle. Damage to the finished surface is thereby avoided.By means of the half shields which can be controlled independently of one another according to the invention, a so-called lateral adjustment can also be realized. This is the case, for example, when the left half-shield is retracted, the right half-shield is extended and then both half-shields simultaneously change their position. That is, the right half-shield is retracted and the left half-shield is extended.A further advantage is that the blade can be retracted to the transport width in the shortest possible time by means of the continuously variable hydraulic lateral adjustment of the half blades and can then also be extended again to the maximum working width in the shortest possible time.A further critical point is the driving lane of the host vehicle, since in this driving lane, compaction of the surface takes place by the dead weight of the host machine. When the desired surface level is reached with a crossing, this is not a great problem. However, if the level is applied layer by layer with several passes and is subsequently compacted, an increase in the level results at the point where the drive belts have been repeatedly passed over. This is achieved in that the material is already pre-compacted at this point and can no longer be compacted to the same extent as at the points at which it was applied loosely. Naturally, when this work is done on a free surface, the starting path of the carrier machine can always be laterally offset. However, if a structural contour such as a wall is present on one side or even on both sides of the surface, in which the surface extends all the way to the edge, this cannot be done with a conventional blade and leads to the above-mentioned problem. However, the laterally displaceable half shields allow the carrier vehicle to displace its runway and nevertheless produce the surface cleanly up to the edge contour.For fastening the half-shields, the invention provides for two superposed grooved profile strips to be inserted flush into the front side of the main shield just above the cutting edge, wherein these two guide strips arranged parallel to one another extend over the entire width of the main shield. These profiled grooved strips are engaged by grooved stone strips which are fastened to the rear side of the half shields.The guide strips preferably have a T-profile, but a different profile shape such as a dovetail profile is also possible. The sliding block strips have a matching profile.The sliding block strips are preferably fastened to the half-plates by means of a screw connection and then each run in the groove profiles of the main plate. Each half-plate thus runs with its sliding block strip in its own guide of the main plate. The length of the half-shields is about half the length or width of the main shield, wherein the grooved strips preferably extend over the same length as the main shield.It is also advantageously proposed that a flat steel be located on the upper edge of the half-plates, which steel engages back over the main plate, wherein a guide strip can be screwed under this flat steel, which guide strip engages behind a continuous strip on the upper edge of the main plate.Welded to the outer sides of the half-shields is a respective end cover on which the pistons of hydraulic cylinders engage, which retract and extend the half-shields.For this purpose, it is proposed in more detail that two hydraulic cylinders are mounted side by side approximately at half the height of the main shield behind its front wall, the extendable piston rods of which cylinders engage the abovementioned end covers, which are preferably welded to the half shields. The two hydraulic cylinders are installed on the inside in the main shield on two fastening lugs, and their piston rods extend through an opening in the side covers of the main shield approximately at half their height.Since the sliding block strips have the same length as the main plate, the guide grooves of the main plate are always covered even when the cylinders are fully extended, so that no dirt can enter the guide grooves.A cover strip, which travels with the half shield and the slot nut profile, acts like a type of labyrinth seal, thereby ensuring that no dirt reaches the guide region through the gap between the slot nut profile and the slot nut profile.It is also greatly advantageous that flat driver plates are arranged on the outer sides of the half shields, which driver plates can be extended continuously forwards in the direction of travel independently of one another at an angle to the half shields. In this case, the driver plates are each sandwiched between the end cover fastened to the half plate and an outer cover, between which the driver plate can be extended forwards.For the retraction and extension of the driver plates, a hydraulic cylinder is attached to the end cover or the inner plate, respectively, which is connected via intermediate members to the driver plate for its movement.The entrainment plates can advantageously be moved along an oblique path, wherein the angle of the rearward movement increases, so that the entire entrainment units do not slide over the entire length on the completely planar surface.Lateral entrainment plates have been present on dozer blades for a long time. These may be screwed on, welded on or also fastened to the blade by means of a plug-in or folding connection. These types of connections have up to now only been manually separable or adjustable. Since this operation is performed manually, it is of course also associated with a great deal of time. The reason for the attachment of such entrainment plates is that a type of U-plate is formed from the straight plate by the entrainment plates. This U-shape of the shield has the great advantage that more material can be carried along in front of the shield without this material running out to the side.As already described above, transitions from one machining track to the next track are always very critical. In order to make these transitions and the connection to the previous working path clean, the machine operator must always turn the blade laterally back and forth, so that the material always reaches as far as the outer edge of the blade, but also does not run beyond it. If the material runs out laterally, an undesirable accumulation of material occurs. If too little material is present at the edge, so that the level attachment present can be filled, notches or hole-like depressions are produced.In order to facilitate the work for the machine operator, the amount of overlap of the individual work paths can of course be selected to be greater. However, this has the disadvantage that the machining width of each individual working path decreases around the overlap, which naturally also results in a reduction in the surface power.To counteract this problem, lateral entrainment plates are attached to the blade, as described above. The advantage is then obtained in that a certain material buffer is also formed at the outermost edge of the blade. Due to this material buffer, the machine operator no longer has to engage as much in the lateral turning of the blade, and the work path overlap can also be selected to be smaller.In certain operations, this entrainment plate may also have a disadvantageous effect. This can be the case, for example, when the blade is turned laterally in order to offset material laterally. Especially in the case of moist and tough material, such as humus, the material can then be greatly jammed by the entrainment shields. This can then result in material accumulating up to above the blade and flowing over the blade. A further disadvantage is, of course, also that the required drive power of the carrier vehicle increases due to the increased resistance. Since the driver plates according to the advantageous embodiment of the invention can be extended and retracted continuously independently of the machine cab, the optimum machine states can also be produced here in the shortest possible time.In a more detailed embodiment of the extendable driver plates, it is proposed that the driver plate units are constructed like a kind of sandwich, wherein the already above-mentioned inner plate or end cover is welded directly to the half plate. In the middle is the extendable driver plate and on the outside an outer cover is then located.A hydraulic cylinder may be mounted vertically on the inside of the inner plate. This is connected to the movable driver plate via the intermediate members described below.For this purpose, it is proposed in further detail that the hydraulic cylinder mounted vertically on the inner side of the inner plate pushes up and down a sliding strip which is located in a groove of the inner plate. This slide strip is connected at the bottom and at the top by bolts to a second slide strip. This sliding strip runs in a groove of the outer cover. Between the two sliding strips, a roller runs on the connecting bolt. In order to enable this connection between the sliding strips, the extendable driver plate has two elongated holes. On the inner plate, a frame is fitted all around, which is slightly thicker in its material thickness than the extendable driver plate. This frame is open towards the front. Thus, the driver plate is held downwards and upwards and can extend forwards. The rear standing frame part is necessary to prevent dirt from coming into the intermediate space. The lower and upper frame parts, which are parallel to each other, deviate from horizontal alignment and the angle is increasing rearward. This angle is necessary so that the entire driver blade unit does not brush over its entire length on the finished surface. The slots of the driver plate are rotated at an angle to the grooves in the inner plate and the outer cover. This rotation produces an inclined plane which makes it possible for the perpendicular movement of the hydraulic cylinder and the sliding strips to produce a parallel movement of the extendable driver plate with respect to the lower and upper frame parts. Thus, the cylinder pushes the slide bars downward during the extension. The rollers between the sliding blocks also press the driver plate downward. Since the latter then bears against the lower frame parts, a horizontal force is built up by the inclined plane, which force the driver plate pushes forward. When the hydraulic cylinder retracts again, the driver plate abuts the upper frame part and is pulled inward.The connection of the individual functions and advantages results in a blade according to the invention which is excellent in terms of quality and surface performance, especially in the case of precise surface levelings.Further details of the invention will become apparent from the following description of a preferred embodiment and from the drawings. The following are shown: FIGS. 1A to 1B are a front perspective view of the entire blade; FIGS. 2A to 2F are front elevational views of the blade; FIGS. 3A to 3C are sectional rear views of the blade; FIGS. 4A to 4C are perspective views of a driver plate unit with the driver plate extended; FIGS. 5A to 5C show the driver plate unit of FIG. 5 with the driver plate retracted.FIG. 1 shows a perspective view of the entire blade 1, in which a right and a left half-blade 3 are mounted in front of the main blade 2, which half-blades have replaceable cutting edges 4 just like the main blade 2. All connection points 5 ato the carrier device are attached to the main shield 2.The half-shields 3 are curved in such a way that they fit with their rear wall parallel to the contour into the front wall 6 of the main shield 2.End covers 7 are welded to the outer ends of the half shields 3 and form the inner plates of sandwiched driver shield units 8. Between the end covers 7 or the inner plates and outer covers 9 formed by them, a driver plate 10 is arranged in each case, which can be moved in and out in order to form together with the main plate 2 and the two half plates 3 a substantially U-shaped overall plate.In FIG. 1A, both half-plates 3 are extended laterally, whereby the overall width of the blade increases by half the width of the main plate 2. In addition, the two driver plates 10 are extended forward, i.e. in the direction of travel. Between the half shields 3 the cover bands 5 are visible.In FIG. 1B, both half shields 3 are retracted and the driver shield 10 on the left in the figure is extended, while the right driver shield 10 is retracted, i.e. retracted between the outer cover 9 and the inner plate 7.The end views of FIG. 2 show in FIG. 2A both half-plates 3 retracted, while the two driver plates 10 are extended. In contrast to this, both driver plates 10 are retracted in FIG. 2B.In FIG. 2C, both half-plates 3 are furthermore retracted, and only the left-hand driver plate 10 is extended.In FIG. 2D, the right half-shield 3 is extended, while the left half-shield 3 is in the retracted state. Both driver plates 10 are extended. FIG. 2E differs from the preceding figure in that the left half-shield 3 is extended, while the right half-shield 3 is shown in the retracted state.In FIG. 2F, both half-plates are extended, which is also the case for the two driver plates 10.FIG. 3 shows the rear side of the entire blade 1 in a sectional view. Approximately halfway up, in the central main shield 2, two equally level, spaced-apart hydraulic cylinders 11 are mounted internally in the main shield on mounting brackets 12. The piston rods 13 of the hydraulic cylinders 11 extend through openings 14 in side covers 15 of the main shield 2 to the already above-mentioned end covers or inner plates 7 of the half shields 3, which are welded to the half shields 3. In the lower edge region of the blade 1, two superposed grooved profile strips 16 are inserted flush into the front wall 6 of the main blade 2 in the front wall 6 of the main blade 2, which extend over the entire length of the main blade 2. On the rear side of the half shields 2 there is fastened in each case a sliding block strip 17 which engages in its associated sliding block profile strip 16. The sliding block strips 17 also extend over the entire width of the main shield 2.At the upper edge of the half-plates 3, a guide strip 18 is fastened to a bent flat steel element, which engages under a guide strip fastened to the main plate 2.The half-shields 3 are thus guided by the upper and lower guide rails along the front wall 6 of the main shield, being moved forwards and backwards by the hydraulic cylinders 11.In FIG. 3A, the right half-shield 3 is extended, while the left half-shield is retracted. Both driver plates 10 are extended out of their driver plate units 8.In FIG. 3B, both half-plates 3 are retracted, while the driver plates 10 are extended.In FIG. 3C, the left half-shield 3 is extended, while the right half-shield is retracted.FIGS. 4 and 5 show the movement mechanism with which the driver plate 10 is extended in FIG. 4 and retracted, i.e. retracted, in FIG. 5. To the inside of the inner panel 7 welded to the half-shield 3 is fixed a hydraulic cylinder 19 in a vertical position. The hydraulic cylinder pushes up and down with its piston rod a slide rail 21 which is located in a groove 22 of the inner plate 7; namely in FIG. 4 into the lower position. This slide strip 21 is connected at the bottom and at the top by bolts to a second slide strip 23 which runs in a groove 24 of the outer cover 25. Between the two sliding strips 21 and 23 a roller runs on the connecting bolt. In order to make this connection possible between the sliding strips 21 and 23, the extendable driver plate 10 has two slots 26. Thus, the driver plate 10 is held downward and upward and can extend forward. The rear standing frame part is necessary for no dirt to enter the intermediate space. The lower and upper frame parts, which are parallel, deviate from horizontal alignment, with the angle α increasing rearward. This rising angle has the effect that the entire driver blade unit 8 does not brush over its entire length on the finished surface. The slots 26 of the driver plate 10 are rotated at an angle to the grooves in the inner plate 7 and the outer cover 25. This rotation produces an inclined plane which makes it possible for the perpendicular movement of the hydraulic cylinder 19 and the sliding strips 21, 23 to produce a parallel movement of the extendable driver plate 10 with respect to the lower and upper frame parts. Thus, the cylinder 19 pushes the slide bars 21, 23 downward during the extension, as is shown in FIG. 4. The rollers between the sliding blocks also press the driver plate 10 downward. Since the latter then bears against the lower frame parts, a horizontal force is built up by the inclined plane, which force the driver plate 10 presses out forwards. When the hydraulic cylinder retracts again, as shown in FIGS. 5A to 5C, the driving plate 10 abuts on the upper frame part and is pulled inward.

Claims

A blade with a central main blade (2), wherein a right and a left half blade (3) are arranged in front of the main blade (2), which have a curvature such that they fit with their rear side into the main blade (2) essentially parallel to the contour, wherein the half blades (3) can be extended independently of one another continuously laterally beyond the main blade (2), characterized in that two groove profile strips (16) lying one above the other are inserted closely above the cutting edge (4) and parallel to the latter into the front wall (6) of the main blade (2) flush with the front side of the front wall (6) of the main blade, which extend over the entire width of the main blade (2), and that groove block strips (17) engage into these profile strips (16), which are fastened to the rear side of the half shields and, in the retracted position of the half shields, likewise extend over the entire width of the main shield ( 2).A blade according to claim 1, characterised in that a flat steel is fastened to the upper edges of the half blades (3), which is bent in such a way that it engages with a guide strip (18) fastened thereto behind a continuous strip which is attached to the upper edge of the main blade (2).A blade according to claim 1 or 2, characterised in that a cover strip (5) travels with each of the two half blades (3) and the slot nut strips (17), so that no foreign substances pass through the gap between the slot nut strips (17) and the profile strips (16).The blade according to any one of claims 1 to 3, characterized in that the half-blades (3) are each approximately half as wide as the main blade (2).A blade according to one of claims 1 to 4, characterised in that the half-blades (3) can be extended by approximately 1 / 4 of the width of the main blade (2).The blade according to any one of claims 1 to 5, characterized in that two hydraulic cylinders (11) are mounted behind the front wall (6) of the main blade (2) approximately at half the height thereof, the extendable piston rods (13) of said hydraulic cylinders engaging end covers or inner plates (7) which are fastened, preferably welded, to the outer sides of the half blades (3).

Images