EP3075910A1 - Leveling screed unit for a paver - Google Patents

Abstract

A skid plate assembly (24) for a paver comprising a skid plate (243) having a scoop-side surface (242) and a working-side surface (241). One side edge of the slide plate unit includes a run-up ledge (244) that protrudes from the scoop-side surface of the slide plate such that a side surface of the slide plate unit includes an outer surface of the scoop ledge. In particular, a ramming sliding surface (245) is formed on the side surface of the sliding plate unit, which comprises the outer surface of the run-up strip.

Description

TECHNICAL AREA

The present description relates to a sliding plate unit of the type described in claim 1. It further relates to a screed for a paver and a paver comprising a sliding plate unit of the type mentioned.

TECHNOLOGICAL BACKGROUND

Asphalt pavers or pavers include a tractor and a screed. The screed is arranged on a rear side of the paver in the working direction. The screed is attached for example by means of support arms on the tractor, wherein the support arms are designed raised and lowered. This makes it possible to raise the screed on the one hand for moving the asphalt paver, on the other hand, to lower the screed in a working position. In the working position, the screed loads with its own weight It is also known to load or unload the screed in order to vary the pressure which the screed exerts on the mix to be processed. In the production of a road surface, a mix of a mix container, which is arranged for example on a - viewed in the direction of - front of the tractor, conveyed by means of the scraper belts to the rear of the tractor and distributed on the ground by a screw to the width of the dragged Bohle. The screed is dragged with a smoothing surface over the mix distributed on the ground. The screed comprises on its underside a sliding plate or a screed plate. A scraper-side surface of the sliding plate in this case points towards the frame of the screed, while a working surface of the sliding plate forms the smoothing surface of the screed or is at least an integral part of the smoothing surface, and is intended to slide over the mix. The mix is compacted and smoothed by the weight of the screed and the shape of the surface to be produced is impressed.

Further, it is known that the screed in the working direction in front of the sliding plate and behind the screw comprises a so-called tamper, which pre-compacted by an up and down movement distributed by the screw mix and pressed under the sliding surface of the screed, such that the smoothing surface of the Bohle can slide directly over the mix instead of having to slip on this. So that the interaction of rammer and smoothing surface works as well as possible, it is desirable if the web of the rear edge of the rammer and the leading edge of the smoothing surface in the working direction are flush with each other, such that between a leading edge of the Bohlengleitfläche and the rammer no mix up can work.

PRESENTATION OF THE SUBJECT OF THE PRESENT DESCRIPTION

There is therefore described a sliding plate unit which makes it possible to obtain improved results on a screed with a rammer. In particular, the sliding plate unit described makes it possible to ensure a smooth smooth surface under all circumstances.

According to one aspect of the present disclosure, the slide plate unit is adapted to be flush with the trajectory of a rear side of the rammer in the working direction.

According to another aspect of the present description, the slide plate unit is designed to provide a mating surface for the back of the rammer throughout the stroke of the rammer.

It is a further object that the sliding plate unit described can be replaced in an exchange with the least possible effort and low downtime of the paver. Furthermore, can be seen as the goal that the Gleitplatteneinheit ensures that the smoothest possible smooth surface of the screed is guaranteed.

Other effects and advantages of the objects described herein, whether explicitly stated or not, will become apparent in light of the present description.

This is achieved by means of the sliding plate unit described in claim 1.

Described is a skid plate unit for a paver comprising a skid plate, the skid plate having a scoop-side surface and a working-side surface. On one side edge of the sliding plate unit, this comprises a run-up strip which projects from the scarf-side surface of the sliding plate, such that a side surface of the sliding plate unit comprises an outer surface of the scarfing strip. The working side surface is that surface of the slide plate which is provided and configured to slide on a mix. For this purpose, it has, for example, an at least approximately smooth surface in order to produce a uniformly smooth surface of the mixed material. The The screed-side surface of the slide plate is defined as the area that is provided and configured to be disposed toward the frame of the screed. For this purpose, it may, for example, comprise means which are suitable and provided for connecting the sliding plate unit to the screed or the screed frame. By the means are here for example also flanges or contact surfaces to understand, with which the sliding plate unit is pressed in a screw against corresponding mating surfaces.

The slide plate unit described herein is suitable for being mounted on a solid plank, as well as on the base plank and / or a pull-out plank of a widenable plank.

In particular, the run-on strip is arranged on a side edge of the slide plate unit, which is intended to be arranged on a front side of the screed in the working direction. Furthermore, in particular, the run-up strip extends at least substantially over the entire transverse extent of this side edge of the slide plate unit. According to a further aspect of the present description, the run-up bar is dimensioned so that the height of the respective side edge, that is, the thickness of the slide plate plus the mass to which the run-up rail protrudes from the screed-side surface, is greater than the stroke of a rammer disposed on a screed for use with the sliding plate unit. In particular, the height of the respective side edge is greater by an amount which is sufficient to form an adequate counter bearing surface with the rammer and to form a sufficient guide even in the uppermost position of the stroke movement of the rammer. The height of the side edge is for example 18 mm or more. This condition is fulfilled in particular essentially over the entire transverse extent of the relevant side edge.

According to a further aspect of the present description, a smoothing surface of the sliding plate unit passes directly and without rounding radii into the above-mentioned side wall of the sliding plate unit, which comprises the outer surface of the run-on strip. "Without rounding radii" is in this context to understand that a transition radius between the two surfaces in each case is less than 2 mm. In one embodiment, as far as is technically possible, an angular transition without a radius of curvature is realized, and in particular an at least approximately perpendicular transition between these two surfaces.

It is known in the art, for example, to perform a run-up strip and a sliding plate as separate elements and to mount individually to the screed. However, it is then necessary, for example, after each replacement of the sliding plate, which is a wear part, to readjust the vertical position of the run-up strip on the screed so that the underside of the run-up strip is flush with the working surface of the slide plate, so that no steps in the sliding surface arise the screed, which would negatively affect the work result. This adjustment to be made manually and in the field on the one hand contains sources of error, on the other hand, these adjustment work is time-consuming, which has an influence on the service life of the machine when replacing the sliding plate. According to the present disclosure, the sliding plate unit is provided as a whole unit, so that the entire smoothing surface of the sliding plate unit is made stepless. At the same time, a flat front side of the sliding plate unit can be ensured. On the one hand, this eliminates sources of error and, on the other hand, reduces repair times.

In one embodiment of the sliding plate unit, the side surface of the sliding plate unit, which includes or is formed by the outer surface of the wear protection strip, comprises a sliding surface. This sliding surface can be provided as a sliding surface for the back of the rammer, such that the back of the rammer slides during its up and down movement over this sliding surface. In particular, the ramming sliding surface can be designed for this purpose at least substantially planar.

According to one aspect of the present description, the sliding plate and the stop bar can be made integral with each other. That is, the sliding plate and the start bar already form a single component, without having to be joined. In particular, the sliding plate and the stop bar can be made in one piece and completely without joints with each other. In further embodiments of the sliding plate unit according to the present description there is at least one joining connection between the sliding plate and the starting strip, and in particular embodiments are disclosed in which the sliding plate unit is joined by means of a joint connection of individual parts and wherein these individual parts comprise a sliding plate and a stop bar.

The joint connection comprises, for example, a welded joint. In one aspect of the present description, the sliding plate and the run-in bar are in particular joined exclusively by means of a welded connection.

Furthermore, a sliding plate unit is disclosed in which the joint connection comprises positive-locking elements. In exemplary but non-limiting embodiments, the interlocking elements include dowel pins, where the dowel pins may be cylindrical or conical dowel pins, or even a combination thereof.

Furthermore, the joining of the sliding plate unit may comprise a riveted joint and / or a screw connection.

Of course, this list of possible joints is not conclusive. Likewise, different types of joint connection can be combined. For example, in one exemplary embodiment, the run-up strip and the slide plate can first be fixed to one another in a fixed position relative to one another by means of positive-locking elements, such as dowel pins, rivets or screws, and then welded. Likewise, the run-up bar and the slide plate can be fixed to each other, for example by means of dowel pins in their position and then screwed or riveted. In each of these cases, the joint connection comprises several types of joining elements.

According to another aspect of the present disclosure, a smoothing surface of the sliding plate unit is at least substantially free of steps. In more specific embodiments, the smoothing surface of the sliding plate unit is at least substantially planar. In accordance with further aspects of the present disclosure, a ramming sliding surface of the slide plate unit is at least substantially step-free. In more specific embodiments, the ramming sliding surface of the sliding plate unit is at least substantially planar. These aspects come into play, in particular, when the sliding plate and the starting strip are joined, and the joint comes to lie in the smoothing surface or the ramming sliding surface. On the one hand, it will be necessary to arrange the slide plate and the run-up bar with their corresponding surfaces flush with each other before producing the joint connection. If the joint connection comprises a welded joint, it may be advantageous to ground the weld joint in the region of the smoothing surface or the ramming sliding surface or to smooth it in some other suitable manner. If the connection is to be produced primarily by form-fitting elements, for example by screwing or riveting, it may also be advantageous, depending on the size and position of the remaining gap, to fill the joint by applying material, for example by welding, and Smooth surface.

It is also possible that the smoothing surface and / or the ramming sliding surface is post-processed after joining as a whole.

In a further embodiment, at least one mating surface is arranged on an inner surface of the run-up ledge facing toward the screed-side surface of the slide plate in a region which projects from the scarf-side surface of the slide plate. This mating surface is in particular arranged and provided in such a way that it rests against corresponding counter-bearing surfaces of the screed frame during assembly of the sliding plate unit. This ensures a defined horizontal positioning of the sliding plate unit on the screed frame. This in turn allows the cooperating treads of a rammer and the slide plate unit to securely engage each other are positioned so that the tamper tension-free and on the other hand without play, or at least without undue play, on the slide plate unit formed, provided for this purpose, sliding surface and can run off.

Further disclosed is a screed for a paver, comprising a slide plate unit according to the present description, wherein the run-up bar is arranged pointing to a front side of the screed. In particular, the screed comprises a ramming device and a ramming sliding surface is formed on the sliding plate unit, with a rear side of the rammer resting against the ramming sliding surface of the sliding plate unit. In one embodiment, the screed is a widenable screed; In this case, the base board and / or at least one Ausziehbohle a sliding plate unit according to the present description.

A paver comprises a tractor and a screed of the type described above.

As mentioned in the introduction, the sliding plate is subject to wear and must be replaced as soon as it has worn down to a certain minimum thickness. In the context of the present description, therefore, a screed is also disclosed which is equipped with at least one device for determining the wear of the sliding plate. To determine the wear of the sliding plate, the remaining thickness of the sliding plate is determined particularly expediently.

In particular, the wear determining device comprises a suitable measuring device for determining the remaining thickness of the sliding plate. The measuring device may be arranged on the screed frame, but is arranged in specific embodiments directly on the sliding plate unit respectively directly on or in the sliding plate.

In particular, the measuring device is arranged on the sliding plate or a sliding plate unit of the type described above. Farther In particular, the measuring device is arranged on a scoop-side surface of the slide plate and / or used starting from the scoop-side surface in the slide plate. In this respect, a sliding plate and a sliding plate unit of the type described above are disclosed which comprise a measuring device. Similarly, a sliding plate and a sliding plate unit of the type described above are disclosed, which have suitable means for receiving and / or attachment of at least one measuring device. These receiving and / or fastening means are arranged in particular on the bohlenenseitigen surface of a sliding plate.

In particular, an ultrasonic measuring head can be used which determines the remaining thickness of the sliding plate in a manner known per se by means of ultrasonic signals. The ultrasonic measuring head is attached in one embodiment according to the present description by means of suitable fastening means on the scoop-side surface of the sliding plate.

It can be arranged one or more measuring devices, wherein in the case of multiple measuring devices, these may be arranged and provided in such a way to determine the wear or the remaining thickness of the sliding plate at different points of the sliding plate.

In a further embodiment, the measuring device comprises at least one electrically conductive element, which is arranged within the sliding plate. The conductive element is electrically insulated from the sliding plate and extends from the scoop-side surface of the sliding plate into the sliding plate by a certain distance. The electrically conductive element comprises outside the sliding plate two electrical connections, between which the electrically conductive element establishes a connection. If the sliding plate is now worn down to a residual mass which corresponds to the depth by which the electrically conductive element extends into the sliding plate, the electrically conductive element is severed. By detecting the interruption of a current flow through the electrically conductive element can now be determined that the sliding plate to just that remaining Remaining measure is worn. The electrically conductive element is for example a wire or cable.

In a further embodiment, a plurality of electrically conductive elements are used at one point of the sliding plate, which protrude differently far into the sliding plate. This makes it possible to determine the remaining thickness of the sliding plate, or the wear, incrementally.

According to one aspect of the present disclosure, at least one electrically conductive element is inserted into a blind bore emanating from the scarf-side surface of the sliding plate and potted there with a suitable material. According to another aspect of the present disclosure, one or more electrically conductive elements are contained within a gauge head which is inserted and appropriately secured in a blind bore extending from the scoop-side surface of the skid plate. In this case, for example, the measuring head can be screwed directly into the blind bore. The measuring head can furthermore be screwed or riveted to the sliding plate by means of a flange. Likewise, this measuring head can be pressed into the sliding plate. In further embodiments, the measuring head is bonded, soldered, welded, or caulked to the sliding plate. Furthermore, any type of fasteners used herein can be additionally secured by gluing, soldering, caulking, welding or other non-destructively releasable connections. On the one hand, this offers security against loosening of the measuring head during use under demanding conditions, which include a load due to vibrations and temperature changes. On the other hand, a non-destructive detachable connection provides security against mishandling during maintenance or servicing. Finally, the wear detection by means of electrical conductors is inexpensive and simple, and is destroyed anyway when cutting the conductor, so that such a measuring head can be easily carried out as an interchangeable built-integral part of the sliding plate or sliding plate unit.

It goes without saying that each of the conductive elements must have two out of the measuring head arranged and accessible connections, which are connected by the conductive element.

Of course, the types of fastening of a measuring device described above can also be used for other types of measuring devices which are suitable in particular for measuring wear. Of course, the attachment of the measuring device on the sliding plate or sliding plate unit can then also be provided so that a measuring device can be reused when replacing the sliding plate or sliding plate unit.

The list of types of recording and mounting the measuring device is not to be understood as exhaustive.

According to one aspect of the present description, a screed comprises connection means for lines via which signals are transmitted to the measuring device.

An exemplary road paver includes a screed equipped with a wear gauge for a slide plate or slide plate unit. A signal generated by the Verschleissmesseinrichtung can be displayed, for example, in a control station of the paver. Furthermore, the screed can be equipped with its own control room. In this case, a signal generated by the Verschleissmesseinrichtung can be displayed in the control room of the screed. A signal generated by the Verschleissmesseinrichtung can continue to be displayed in a control station of the paver and / or in a control room of the screed.

The above-described embodiments of the described objects can of course be combined with each other. It goes without saying that the described technical teachings are applicable to both the base screed and extendable screeds. Further, not specifically disclosed Embodiments of the teaching of this document will be readily apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1

einen Strassenfertiger;

Fig. 2

eine Ansicht einer Bohle eines Strassenfertigers;

Fig. 3

ein erstes Ausführungsbeispiel einer Gleitplatteneinheit;

Fig. 4

ein zweites Ausführungsbeispiel einer Gleitplatteneinheit;

Fig. 5

ein drittes Ausführungsbeispiel einer Gleitplatteneinheit;

Fig. 6

einen Strassenfertiger, bei dem in einer Gleitplatte oder Gleitplatteneinheit eine Verschleissbestimmungseinrichtung angeordnet ist;

Fig. 7

beispielhafte Ausführungsformen von Gleitplatten mit Verschleiss-Messeinrichtungen.

The facts presented here are explained in more detail below with reference to selected embodiments shown in the drawing. Show in detail

Fig. 1

a paver;

Fig. 2

a view of a screed of a paver;

Fig. 3

a first embodiment of a slide plate unit;

Fig. 4

a second embodiment of a sliding plate unit;

Fig. 5

a third embodiment of a slide plate unit;

Fig. 6

a road paver in which a wear determining device is disposed in a slide plate or slide plate unit;

Fig. 7

exemplary embodiments of sliding plates with wear measuring devices.

The drawings are very schematic. Details not necessary for understanding the described objects have been omitted. Furthermore, the drawings show only selected embodiments and should not be used to limit the objects described in the claims. Not shown embodiments may well be covered by the claims.

EMBODIMENTS

The FIG. 1 shows a paver 1, comprising a tractor 10 and a plank 20. In the present case, a tracked paver is shown. It is understood that the following explanations also apply to a wheeled paver. The tractor 10 includes a drive 11, a chassis 12, and a Mischgutbehälter 13. Furthermore, a control station 14 is arranged on the tractor. From this control station, the paver can be driven and operated. The screed 20 is coupled by means of support arms 15 to the tractor. By means of hydraulic cylinders 16, the support arms 15 can be pivoted about the axis of rotation 151, whereby the screed 20 can be raised and lowered. On the screed 20 a control station 21 is arranged in this example, from which elements of the screed can be operated, such as the width adjustment of a Ausziehbohle. When finishing a road surface, the paver moves in the direction shown by the arrow 2. Mixture is conveyed by means not shown scraper belts from the Mischgutbehälter 13 on the ground 31 in the direction of travel behind the tractor and in front of the screed. Mixture 32 deposited there is distributed by means of a worm 22 in the width of the screed, pressed down by a tamper 23, which moves alternately up and down, and finally compacted by a sliding plate unit 24 of the screed by the weight of the screed resting thereon and smoothed. In this way, behind the road paver a smoothed and possibly contoured road surface 33. As the sliding plate unit is pulled over the mix, it is subject to constant wear.

In FIG. 2 a view of the screed 20 is shown. A slide plate unit 24 is connected to a screed frame 25. The slide plate unit 24 comprises a work-side surface 241, which is intended to slide over the mix, and a screed-side surface 242. In the working direction 2 in front of the slide plate unit, the rammer 23 is arranged. This moves, as indicated by the arrow 231, up and down, and thus pushes mix below the sliding plate unit 24. The stroke of the rammer is for example at 5 mm. To achieve a clean work result, it is important that the rammer rests with its rear side as flush as possible on the slide plate unit. This means, ideally, the back of the rammer 23 slides up and down at a front of the slide plate unit 24.

In FIG. 3 is detail "A" off FIG. 2 illustrated with a first exemplary embodiment of the sliding plate unit. The slide plate unit 24 is composed of the slide plate 243 and the stop bar 244. In this case, the run-on strip 244 is fastened to a side edge of the slide plate 243 located in the direction of movement 2, such that the corresponding side edge of the slide plate unit comprises the outer surface of the run-up bar. The run-up strip 244 projects from the screed-side surface 242, and terminates flush with the work-side surface 241. In this case, the working-side surface 241 of the sliding plate comprises a bevel 241 a. The run-up bar 244 and the slide plate 243 are joined by welding in this example. In this case, a fillet weld 247 is arranged on the screed-side surface 242, while another weld seam 246 fills the joint on the side of the work-side surface. The seam is further sanded or smoothed in some other suitable manner to form a smooth work surface. The side surface of the slide plate unit 24, which comprises the outside of the stop bar 244, forms a ramming sliding surface 245. The rammer 23 rests against the ramming sliding surface 245 with a tamper back 232 and slides along the ram surface as indicated by the arrow 231 Rammer sliding surface up and down. Dashed the lowest position of the rammer 23 is indicated. Furthermore, a recess with a machined mating surface 250 is incorporated on a rear side of the run-on strip, that is to say a side of the run-up strip which points to the screed-side surface of the slide plate. This serves to position the sliding plate unit accurately and precisely in the horizontal direction on the screed frame. Thus, an at least largely play-free and at the same time at least largely tension-free running of the rammer on the rammer sliding surface can be ensured. In particular, a mating surface on both sides-which laterally refers to the working direction-of the sliding plate unit is arranged. Likewise, the recess with the mating surface could extend over the entire width of the stop bar, whereby it is again possible To arrange on such a recessed surface smaller surfaces finely machined mating surfaces.

Such horizontal mating surfaces can also have the sliding plate units according to the embodiments listed below; however, these may also be arranged so that they are not visible in the illustrated side views.

A second exemplary embodiment of a sliding plate unit is shown in FIG FIG. 4 shown. In contrast to the representation in FIG. 3 the stop bar 244 is not disposed directly on a side edge of the slide plate 243, but placed on the screed side surface 242, adjacent to the front side in the working direction 2 side of the sliding plate and flush with this. Again, this is to be understood in the context of the present disclosure as "arranged on a side edge of the sliding plate", as here also includes a side surface of the Gleitplatteneinheit an outer surface of the stop bar. The weld 248 is also sanded or otherwise smoothed so that an outer side of the run-up rail and the front side edge of the slide plate together form a flat ramming sliding surface.

Finally, in FIG. 5 outlined a third exemplary embodiment in which the stop bar 244 is joined by means of a screw connection indicated at 249 with the sliding plate. Of course, it is also possible here to fill the joint on the side of the working surface 241, for example by welding, and then smooth the surface of this compound by means of a suitable processing.

FIG. 6 shows a road finisher, wherein the sliding plate is provided with a Verschleissmesseinrichtung 40, wherein in the control stations 14 of the tractor and 21 of the Bohle display devices 41 and 42 are arranged, with which signals of the Verschleissmesseinrichtung 40 can be displayed.

FIG. 7 shows exemplary embodiments of sliding plates 243 with Verschleissmesseinrichtungen 40. In a first exemplary Embodiment according to FIG. 7a) a conductor loop 43 is inserted from the scoop-side surface of the slide plate 243 forth in the sliding plate.

When the slide plate is worn down to a dimension D in operation, the conductor 43 is severed. An interruption of a current flow can be detected and a signal can be displayed accordingly. In the embodiment according to the FIG. 7b are three conductor loops 43, 44, and 45 installed in a functioning as a measuring head sleeve 46, which in turn is arranged in a receiving opening in the sliding plate 243. The three conductor loops reach different depths into the sliding plate. Each time a residual thickness D1, D2, and D3 is reached, one of the conductor loops is severed, and again an interruption of a current flow can be detected and displayed, whereby an incremental wear measurement is possible.

As already explained above, the wear determining device can also be realized by means of other measuring means.

Although the subject matter of the present description has been explained with reference to selected exemplary embodiments, these are not intended to limit the claimed invention. The claims include embodiments that are not explicitly illustrated, and embodiments that depart from the examples shown are nevertheless covered by the claims.

LIST OF REFERENCE NUMBERS

1

Asphalt pavers

2

Direction of travel, working direction

10

tractor

11

drive

12

landing gear

13

material hopper

14

control station

15

Beam

16

hydraulic cylinders

20

Bohle

21

control station

22

slug

23

masher

24

A skid plate

25

screed frame

31

underground

32

mix

33

road surface

40

Verschleissmesseinrichtung

41

display

42

display

43

Head strap

44

Head strap

45

Head strap

46

Sleeve, measuring head

151

axis of rotation

231

Stampfer movement

232

Stampfer back

241

working surface

241a

bevel

242

scaffold-side surface

243

sliding plate

244

approach strip

245

Stampfer sliding surface

246

Weld

247

Weld

248

Weld

249

screw connection

250

horizontal mating surface

D

Rest Dick Mass

D1

Rest Dick Mass

D2

Rest Dick Mass

D3

Rest Dick Mass

Claims (15)

A skid plate unit (24) for a paver comprising a skid plate (243) having a scoop side surface (242) and a working side surface (241), and wherein a side edge of the skid plate assembly comprises a ramp (244) extending from the scoop side surface of the skate Sliding plate protrudes, such that a side surface of the Gleitplatteneinheit includes an outer surface of the run-up strip. Slide plate unit according to claim 1, wherein on the side surface of the sliding plate unit, which comprises the outer surface of the stop bar, a rammer-sliding surface (245) is formed. Sliding plate unit according to one of the preceding claims, wherein the sliding plate and the stop bar are integrally formed with each other. Sliding plate unit according to claim 3, wherein the sliding plate and the stop bar are integral with one another and without joints. Sliding plate unit according to one of the preceding claims, characterized in that it has at least one joint connection. Sliding plate unit according to claim 5, characterized in that the sliding plate and the starting strip are joined by means of a joint connection. Slide plate unit according to one of claims 5 or 6, characterized in that the joint connection comprises a welded connection. Sliding plate unit according to one of claims 5 to 7, characterized in that the joint connection comprises positive-locking elements. Sliding plate unit according to one of claims 5 to 8, characterized in that the joint connection comprises a riveted joint and / or a screw connection. Sliding plate unit according to one of the preceding claims, wherein a smoothing surface of the sliding plate unit is at least substantially free of steps and / or flat. Sliding plate unit according to one of the preceding claims, wherein on one of the bohlenenseitigen surface of the sliding plate hinweisend arranged inner surface of the stop bar in a region which projects from the scoop-side surface of the sliding plate, at least one mating surface (250) is arranged. Sliding plate unit according to one of the preceding claims, characterized in that it comprises at least one wear measuring device (40), wherein the wear measuring device is in particular fixedly mounted in or on the slide plate unit (24), and wherein in particular the measuring device fixed in or on the slide plate (243) is installed, and further wherein in particular the measuring device for a measurement of the thickness (D, D1, D2, D3) of the sliding plate is suitable. A screed (20) for a paver comprising a skid plate assembly according to any one of the preceding claims, wherein the skid rail (244) is disposed to face a front side of the board. The screed for a paver according to claim 13, wherein the screed comprises a rammer (23) and a ramming sliding surface (245) is formed on the sliding plate unit (24), and a ram (232) rests against the ramming sliding surface. Road paver comprising a tractor and a screed according to one of claims 13 or 14.

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