ROAD PAVER WITH HEIGHT-ADJUSTABLE PRE-SCRAPER BLADE

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims foreign priority benefits under 35 U.S.C. § 119 (a)-(d) to European patent application number EP 24163777.6, filed Mar. 15, 2024, which is incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to a road paver and a method of operating a road paver.

BACKGROUND

Road pavers are provided for producing a paving layer from a paving material, such as asphalt, and generally comprise a chassis and working aggregates arranged on the chassis, such as a material hopper, a screed, a longitudinal conveying device and a transverse distribution arrangement.

The screed usually has a base screed and laterally adjacent extension screed parts. The width of the screed and thus the width of the paving layer, also known as the working width, may be varied and adjusted using the extension screed parts. Height-adjustable pre-scraper blades may be arranged in front of the extension screed parts in order to regulate the amount of paving material in front of the extension screed parts. This allows the forces on the extension screed parts resulting from the displacement resistance of the paving material to be reduced. Such an arrangement of pre-scraper blades is known from EP2169117B1. Height-adjustable pre-scraper blades in front of the base screed are not known from the state of the art. If the working width of the screed is changed quickly, this may feed overfilling of the screw channel and overflow of paving material over the screed front wall, which may have a negative effect on the paving quality of the paving layer.

SUMMARY

An object of the present disclosure is to ensure a constant paving quality of the paving layer, in particular when the working width of the screed is changed. This object is solved by a road paver according to the disclosure or a method for operating a road paver according to to the disclosure.

According to a first aspect of the disclosure, a road paver for producing a paving layer from a paving material comprises a screed, a transverse distribution arrangement and a pre-scraper arrangement. The screed has at least one base screed. The transverse distribution arrangement is adapted to distribute the paving material transversely to a drive direction of the road paver in front of the screed. The pre-scraper arrangement is arranged behind the transverse distribution arrangement in the drive direction. The pre-scraper arrangement may have a height-adjustable pre-scraper blade. The height-adjustable pre-scraper blade may be arranged in the region of the base screed.

The drive direction may correspond to the drive direction of the road paver during paving of the paving material and is also referred to as the paving direction. The terms drive direction and paving direction are used in particular as synonyms in this application.

The height-adjustable pre-scraper blade may be used to control or limit the amount of paving material in front of the screed, in particular the base screed. This allows the forces acting on the screed, which result in particular from the displacement resistance of the paving material, to be controlled or limited. This means that the screed may need to be less rigid. In addition, a more even installation of the paving material may be ensured. Another advantage is that the paving material may be transported more quickly to the lateral edge regions of the screed when the paving width is increased, in particular by extending the extension screed parts to the side. Material segregation of the paving material may also be reduced by the height-adjustable pre-scraper blade.

The height-adjustable pre-scraper blade may be arranged in a central region of the road paver. The central region of the road paver may comprise the longitudinal axis, in particular the central longitudinal axis of the road paver. The height-adjustable pre-scraper blade may be arranged in the region of the central longitudinal axis of the road paver. The height-adjustable pre-scraper blade may be arranged in a central region with respect to the transverse direction of the road paver. The transverse direction of the road paver may extend orthogonally to the drive direction of the road paver. The longitudinal axis of the road paver may extend parallel to the drive direction. The longitudinal axis of the road paver may extend through the center of gravity of the road paver.

The height-adjustable pre-scraper blade may extend substantially orthogonally to the drive direction or the longitudinal axis of the road paver. The height-adjustable pre-scraper blade may extend substantially transversely to the drive direction and in a vertical direction. A front side of the height-adjustable pre-scraper blade may be substantially orthogonal to the drive direction.

The height-adjustable pre-scraper blade may be movable in height pneumatically, hydraulically, electrically and/or mechanically. The pre-scraper arrangement may have at least one pneumatic cylinder, at least one hydraulic cylinder, at least one electric motor and/or at least one ratchet or crank, which is/are adapted in particular to move the height-adjustable pre-scraper blade in height. The height-adjustable pre-scraper blade may be moveable in height via a remote control.

The height-adjustable pre-scraper blade may be adapted to be adjustable in its vertical position. The height-adjustable pre-scraper blade may be adapted to be adjustable in its vertical position relative to the transverse distribution arrangement. The height-adjustable pre-scraper blade may be adapted to be adjustable in its vertical position relative to the screed, in particular the base screed.

The height-adjustable pre-scraper blade may be adapted to be movable in height. The height-adjustable pre-scraper blade may be adapted to be movable in height relative to the screed, in particular the base screed. The height-adjustable pre-scraper blade may be adapted to be movable in height relative to the transverse distribution arrangement.

The height-adjustable pre-scraper blade allows the vertical distance between the pre-scraper arrangement and a ground to be varied or adjusted. The load on the screed, in particular the base screed, may be kept to a minimum by keeping the vertical distance between the pre-scraper arrangement and the ground. A small vertical distance between the pre-scraper arrangement and the ground allows the paving material to be transported better to the edge regions of the screed, in particular to the extension screed parts of the screed.

The height-adjustable pre-scraper blade may be adapted to be steplessly/continuously movable. The vertical position of the height-adjustable pre-scraper blade may be steplessly/continuously adjustable.

The term height-adjustable is in particular to be understood in the present application as meaning that the vertical position is adjustable.

The height-adjustable pre-scraper blade may be movable in height by at least 50 millimeters, preferably at least 100 millimeters, preferably at least 200 millimeters. The height-adjustable pre-scraper blade may be movable in height by at least 50 millimeters, preferably at least 100 millimeters, preferably at least 200 millimeters, relative to the transverse distribution arrangement. The height-adjustable pre-scraper blade may be movable in height by at least 50 millimeters, preferably at least 100 millimeters, preferably at least 200 millimeters, relative to the screed, in particular to the base screed. The height-adjustable pre-scraper blade may be movable in height by at least 50 millimeters, preferably at least 100 millimeters, preferably at least 200 millimeters, relative to the ground.

The pre-scraper arrangement may have a width of between 110 centimeters and 320 centimeters, preferably between 110 centimeters and 130 centimeters, preferably between 170 centimeters and 190 centimeters, preferably between 230 centimeters and 260 centimeters, preferably between 290 centimeters and 320 centimeters. The width is defined in particular as the extension transverse to the drive direction. The height-adjustable pre-scraper blade may have a width of between 55 centimeters and 160 centimeters, preferably between 55 centimeters and 65 centimeters, preferably between 85 centimeters and 95 centimeters, preferably between 115 centimeters and 130 centimeters, preferably between 145 centimeters and 160 centimeters.

The width of the height-adjustable pre-scraper blade may correspond to the width of the screed. The width of the height-adjustable pre-scraper blade may correspond to the width of the base screed. The width of the height-adjustable pre-scraper blade may correspond to the combined width of the base screed and the extension parts. The width of the height-adjustable pre-scraper blade may correspond to the width of a transverse distribution channel or tunnel of the road paver.

The road paver may have a longitudinal conveyor device. The longitudinal conveyor device may be arranged in front of the screed in the drive direction. The transverse distribution arrangement may be arranged upstream of the screed in the drive direction. The transverse distribution arrangement may be arranged downstream of the longitudinal conveyor device in the drive direction. The road paver may also have a material hopper for receiving the paving material. The material hopper may be arranged upstream of the longitudinal conveyor in the drive direction.

The road paver may have a driving gear. The driving gear may be arranged laterally to the longitudinal conveyor. The driving gear may comprise a left driving gear and a right driving gear. Left and right refer to the drive direction of the road paver. The left driving gear may be arranged laterally to the left of the longitudinal conveyor device. The right driving gear may be arranged laterally to the right of the longitudinal conveyor device. The driving gear, in particular the left and right driving gear, may be a track assembly. The driving gear, in particular the left and right driving gear, may comprise wheels.

The height-adjustable pre-scraper blade may extend transversely to the drive direction, in particular to the left and right, beyond the longitudinal conveyor device. The height-adjustable pre-scraper blade may extend into the driving gear transversely to the drive direction. The height-adjustable pre-scraper blade may be arranged behind the driving gear in the drive direction. The height-adjustable pre-scraper blade may extend transversely to the drive direction from a left lateral end to a right lateral end of the driving gear. The height-adjustable pre-scraper blade may extend transversely to the drive direction from an outer side of the left driving gear to an outer side of the right driving gear.

The height-adjustable pre-scraper blade may extend transversely to the drive direction from a left lateral end to a right lateral end of the base screed. The height-adjustable pre-scraper blade may extend transversely to the drive direction, in particular to the left and right, beyond the base screed.

The transverse distribution arrangement may comprise at least one distribution screw. The transverse distribution arrangement may comprise a left distribution screw and a right distribution screw. The left distribution screw and the right distribution screw may each extend substantially transversely to the drive direction. The left distribution screw and the right distribution screw may be supported on a suspension in the form of a screw suspension or a center bearing block. The transverse distribution arrangement may have further distribution screws.

The height-adjustable pre-scraper blade may be movable in height during operation of the road paver. The height-adjustable pre-scraper blade may be movable in height during a paving run of the road paver. The vertical position of the pre-scraper blade may be adjustable during operation of the road paver.

The vertical position of the height-adjustable pre-scraper blade may be adjustable during operation of the road paver, in particular relative to the transverse distribution arrangement and/or to the screed. In particular, the pre-scraper arrangement may be adapted so that the height-adjustable pre-scraper blade may be lowered and raised during operation of the road paver, in particular relative to the transverse distribution arrangement and/or to the screed.

The height-adjustable pre-scraper blade may be attached at least indirectly to a suspension of the transverse distribution arrangement. The height-adjustable pre-scraper blade may be attached to the suspension of the transverse distribution arrangement via an intermediate piece, for example a support structure. The height-adjustable pre-scraper blade may be attached directly to the suspension of the transverse distribution arrangement. The suspension of the transverse distribution arrangement and the height-adjustable pre-scraper blade may be attached to the same component. The suspension of the transverse distribution arrangement may be attached to a transverse distribution fixture. The height-adjustable pre-scraper blade may also be attached to the transverse distribution fixture.

The height-adjustable pre-scraper blade may be attached at least indirectly to the screed, in particular the base screed. The height-adjustable pre-scraper blade may be attached to the screed, in particular the base screed, via an intermediate piece, for example a support structure. The height-adjustable pre-scraper blade may be attached directly to the screed, in particular the base screed.

The transverse distribution arrangement may be movable in height, in particular relative to the screed. The transverse distribution arrangement may be movable in height relative to the ground. The transverse distribution fixture or the suspension of the transverse distribution arrangement may be attached to the chassis of the road paver via cylinders. The vertical position of the transverse distribution fixture, the suspension of the transverse distribution arrangement, the height-adjustable pre-scraper blade and/or the transverse distribution arrangement may be adjustable via the cylinders. The cylinders may be pneumatic, hydraulic or electric cylinders.

The height-adjustable pre-scraper blade may be movable in height relative to the transverse distribution arrangement. The vertical position of the pre-scraper blade may be adjustable relative to the transverse distribution arrangement. An adjustment arrangement, which is arranged between the height-adjustable pre-scraper blade and the transverse distribution arrangement, may be adapted to move the height-adjustable pre-scraper blade in height relative to the transverse distribution arrangement. The adjustment arrangement may have at least one pneumatic, hydraulic or electric cylinder. The adjustment arrangement may have an electric motor. The adjustment arrangement may have a ratchet or crank.

The height-adjustable pre-scraper blade may be movable in height relative to the screed, in particular the base screed. The vertical position of the pre-scraper blade may be adjustable relative to the screed, in particular the base screed. An adjustment assembly, which is arranged between the height-adjustable pre-scraper blade and the screed, in particular the base screed, may be adapted to move the height-adjustable pre-scraper blade in height relative to the screed, in particular the base screed. The adjustment arrangement may have at least one pneumatic, hydraulic or electric cylinder. The adjustment arrangement may have an electric motor. The adjustment arrangement may have a ratchet or crank.

The pre-scraper arrangement may be arranged substantially, in particular in the drive direction, between the transverse distribution arrangement and the screed. The height-adjustable pre-scraper blade may be arranged substantially, in particular in the drive direction, between the transverse distribution arrangement and the base screed.

The term substantially is to be interpreted in particular in such a way that regions of the individual components may also overlap. The center of gravity of the pre-scraper arrangement may be arranged, in particular in the drive direction, between the center of gravity of the transverse distribution arrangement and the center of gravity of the screed, in particular the center of gravity of the base screed. The center of gravity of the height-adjustable pre-scraper blade may be arranged, in particular in the drive direction, between the center of gravity of the transverse distribution assembly and the center of gravity of the base screed.

The paving material may be transported from the longitudinal conveyor device to the transverse distribution arrangement in the opposite drive direction of the road paver. The paving material may be transported underneath the pre-scraper arrangement, in particular the pre-scraper blade, to the screed, in particular the base screed.

The screed may have extension screed parts in addition to the base screed. The extension screed parts may be arranged laterally next to the base screed, in particular on both sides of the base screed. The extension screed parts may be arranged offset to the base screed in the drive direction.

The extension screed parts or the front edges of the extension screed parts may be arranged in front of the base screed or the front edge of the base screed in the drive direction. The screed may be a front-mount screed, also known as a front screed.

The extension screed parts or the front edges of the extension screed parts may be arranged behind the base screed or the front edge of the base screed in the drive direction. The screed may be a rearmount screed, also known as a rear screed.

The road paver may have a measuring system. The measuring system may be arranged in the drive direction between the transverse distribution arrangement and the screed, in particular the base screed.

The measuring system may be adapted to measure the amount of paving material in front of the screed, in particular the base screed. The amount of paving material is in particular the amount of paving material directly in front of the screed or base screed.

The measuring system may be adapted to measure the height of the paving material between the transverse distribution arrangement and the screed. The height of the paving material is in particular the vertical distance between the upper edge of the paving material and the ground. The measuring system may be adapted to detect or measure the upper edge of the paving material between the transverse distribution arrangement and the screed, in particular the base screed.

The measuring system may be adapted to carry out the measurements continuously and/or at predefined time intervals.

The measuring system may have at least one sensor. The at least one sensor may be arranged in the drive direction between the transverse distribution arrangement and the screed, in particular the base screed. The at least one sensor may be arranged between the pre-scraper arrangement and the screed. The at least one sensor may be arranged between the height-adjustable pre-scraper blade and the base screed.

The at least one sensor may be an optical sensor. The at least one sensor may be a mechanical sensor. The at least one sensor may be a rotary encoder, in particular with a mechanical sensing arm. The at least one sensor may be an electro-optical sensor. The at least one sensor may be a laser distance sensor. The at least one sensor may be an infrared distance meter. The at least one sensor may be an ultrasonic sensor. The at least one sensor may be a camera or several cameras.

The road paver may have several sensors. The sensors may be arranged distributed across the drive direction. A first sensor may be arranged in front of the base screed. A second sensor may be arranged in front of a first extension screed part, which is arranged in particular to the left of the base screed in the transverse direction. A third sensor may be arranged in front of a second extension screed part, which is arranged in particular to the right of the base screed in the transverse direction.

The road paver may additionally have one or more distribution screw sensors. The distribution screw sensor or sensors may be adapted to determine the vertical position of the transverse distribution arrangement, in particular the vertical distance between the ground and a rotation axis of the transverse distribution arrangement running in the transverse direction.

The road paver may also have one or more screed sensors. The screed sensor or sensors may be adapted to determine the vertical position of the screed, in particular the vertical distance between the substrate and a lower edge of the base screed.

The height-adjustable pre-scraper blade, in particular the left and second height-adjustable pre-scraper blades, may have a protrusion on the lower edge pointing in the drive direction. The protrusion may have a triangular cross-section when viewed in the transverse direction, in particular in the form of a right-angled triangle. The surface of the pre-scraper blade formed by the hypotenuse of the triangle may point in the drive direction.

The road paver may have a control unit. The control unit may be configured to adjust the height of the height-adjustable pre-scraper blade, in particular during operation or during a paving run of the road paver.

The control unit may be adapted to receive data from the measuring system. The control unit may be adapted to receive data from the measuring system wirelessly. The transmission of data between the control unit and the measuring system may occur via Bluetooth, WLAN (Wi-Fi) or similar, for example. The transmission of data between the control unit and the measuring system may occur via cable.

The control unit may be configured, in particular in combination with the measuring system, to regulate or control the feed of the paving material upstream of the screed. The control unit may be configured, in particular in combination with the measuring system, to keep the feed of the paving material in front of the screed as constant as possible, in particular in accordance with a predefined target value.

The control unit may be configured, in particular in combination with the measuring system, to feedback control or control the height of the paving material between the pre-scraper arrangement and the screed, in particular the base screed. The control unit may be configured, in particular in combination with the measuring system, to keep the height of the paving material between the pre-scraper arrangement and the screed, in particular the base screed, as constant as possible, in particular in accordance with a predefined target value.

The control unit may be configured to move the height-adjustable pre-scraper blade in height based on the screed height, in particular in combination with measured values from the measuring system. The screed height is in particular the vertical distance between the screed, in particular the lower edge of the base screed, and the ground. The control unit may be configured to adjust the vertical position of the height-adjustable pre-scraper blade based on the screed height, in particular in combination with measured values from the measuring system.

The amount of paving material in front of the screed or the height of the paving material between the pre-scraper arrangement and the screed may be influenced by adjusting the vertical position of the pre-scraper blade. Lowering the pre-scraper blade may feed a lower height or quantity of paving material directly in front of the screed, in particular the base screed. Raising the pre-scraper blade may feed a greater height or quantity of paving material directly in front of the screed, in particular the base screed.

The pre-scraper blade may be rotatable about a rotation axis during operation of the road paver. In particular, the rotation axis runs parallel to the drive direction. The rotation axis may be arranged centrally in relation to the transverse direction of the road paver. The height-adjustable pre-scraper blade may be rotatable about the rotation axis during operation or during a paving run of the road paver.

At turns or inclines in the transverse profile of the paving layer, different amounts of paving material are installed from the left to the right side of the screed. In particular, this requires different heights or quantities of paving material in front of the screed (viewed in the transverse direction). This may be taken into account by a rotation of the height-adjustable pre-scraper blade.

The control unit may be configured to rotate the height-adjustable pre-scraper blade about the rotation axis, in particular during operation or a paving run of the road paver.

The height-adjustable pre-scraper blade may be rotatable by an angle of between minus 10 degrees and plus 10 degrees, preferably minus 3 degrees and plus 3 degrees. The control unit may be configured to rotate the height-adjustable pre-scraper blade by an angle of between minus 10 degrees and plus 10 degrees, preferably minus 3 degrees and plus 3 degrees. The angles are to be understood in particular as a deviation from the horizontal. In particular, at an angle of 0 degrees, the lower edge of the height-adjustable pre-scraper blade is aligned horizontally.

The control unit may be configured to adjust or control the rotation of the height-adjustable pre-scraper blade based on the current installation situation, such as turns and/or the lateral inclination. The control unit may be adapted to adjust or control the rotation of the height-adjustable pre-scraper blade based on the current installation situation in combination with one or more measured values of the measuring system.

The height-adjustable pre-scraper blade may be a first height-adjustable pre-scraper blade. The pre-scraper arrangement may additionally have a second height-adjustable pre-scraper blade. The second height-adjustable pre-scraper blade may be arranged transversely to the drive direction next to the first height-adjustable pre-scraper blade. The second height-adjustable pre-scraper blade may be movable in height relative to the first height-adjustable pre-scraper blade.

The arrangement of two or more height-adjustable pre-scraper blades may be an alternative solution for taking into account turns or lateral inclinations. However, the arrangement of two or more height-adjustable pre-scraper blades may also occur in combination with rotatable height-adjustable pre-scraper blades. The two or more height-adjustable pre-scraper blades may be rotatable about the same or different rotation axes.

The first and second height-adjustable pre-scraper blades may be arranged at the same position as the second height-adjustable pre-scraper blade when viewed in the drive direction. The first height-adjustable pre-scraper blade and the second height-adjustable pre-scraper blade may be arranged aligned with each other, in particular with respect to the drive direction.

The control unit may be configured to adjust the height of the first height-adjustable pre-scraper blade, in particular during operation or a paving run of the road paver. The control unit may be configured to adjust the height of the second height-adjustable pre-scraper blade, in particular during operation or during a paving run of the road paver.

The first and second height-adjustable pre-scraper blades may be vertically movable between 0 millimeters and 150 millimeters, preferably between 0 millimeters and 50 millimeters, preferably between 0 millimeters and 100 millimeters, relative to each other. The control unit may be configured to move the first and second height-adjustable pre-scraper blades vertically between 0 millimeters and 150 millimeters, preferably between 0 millimeters and 100 millimeters, preferably between 0 millimeters and 50 millimeters, relative to each other.

In a first position, the first height-adjustable pre-scraper blade may be arranged higher than the second height-adjustable pre-scraper blade. In a second position, the first height-adjustable pre-scraper blade may be arranged at the same height as the second height-adjustable pre-scraper blade. In a third position, the first height-adjustable pre-scraper blade may be arranged lower than the second height-adjustable pre-scraper blade.

The height-adjustable pre-scraper blade, in particular the first and second height-adjustable pre-scraper blades, may be adapted to be steplessly adjustable. The vertical position of the height-adjustable pre-scraper blade, in particular the first and second height-adjustable pre-scraper blades, may be steplessly adjustable.

The control unit may be adapted to move the height-adjustable pre-scraper blade steplessly in height. The control unit may be adapted to move the first and second height-adjustable pre-scraper blades steplessly in height. The control unit may be adapted to rotate the height-adjustable pre-scraper blade steplessly.

The first and second height-adjustable pre-scraper blades may each be rotatable by an angle of between minus 10 degrees and plus 10 degrees, preferably between minus 3 degrees and plus 3 degrees. The control unit may be configured to rotate the height-adjustable pre-scraper blade by an angle of between minus 10 degrees and plus 10 degrees, preferably between minus 3 degrees and plus 3 degrees. The control unit may be configured to rotate the first height-adjustable pre-scraper blade by an angle of between minus 10 degrees and plus 10 degrees, preferably between minus 3 degrees and plus 3 degrees, in particular independently of the second height-adjustable pre-scraper blade. The control unit may be configured to rotate the second height-adjustable pre-scraper blade by an angle between minus 10 degrees and plus 10 degrees, preferably between minus 3 degrees and plus 3 degrees, in particular independently of the first height-adjustable pre-scraper blade. The control unit may be configured to rotate the first height-adjustable pre-scraper blade together with the second height-adjustable pre-scraper blade.

The angles are to be understood in particular as a deviation from the horizontal. In particular, at an angle of 0 degrees, the lower edge of the height-adjustable pre-scraper blade is aligned horizontally.

Alternatively or in addition to the height adjustment, the first pre-scraper blade and the second pre-scraper blade may be adapted to be rotatable about axes parallel to the drive direction. The first pre-scraper blade may be adapted to be rotatable by a first angle about a first axis parallel to the drive direction. The second pre-scraper blade may be adapted to be rotatable by a second angle about a second axis parallel to the drive direction. The control unit may be adapted to rotate the first pre-scraper blade and the second pre-scraper blade by the same angle. The control unit may be adapted to rotate the first pre-scraper blade and the second pre-scraper blade by different angles, in particular in different directions. For example, the control unit may be adapted to rotate the first pre-scraper blade by a positive angle and the second pre-scraper blade by a negative angle and vice versa.

The control unit may be configured to adjust or control the rotation of the height-adjustable pre-scraper blade based on the current installation situation, such as turns and/or the lateral inclination. The control unit may be adapted to adjust or control the rotation of the height-adjustable pre-scraper blade based on the current installation situation in combination with one or more measured values of the measuring system.

The pre-scraper arrangement may also have a additional plate. The additional plate may be adapted to be adjustable, in particular height-adjustable. The additional plate may be adapted to be adjustable in or against the drive direction or horizontally. The additional plate may be arranged in the drive direction between the height-adjustable pre-scraper blade and the transverse distribution arrangement, in particular the center bearing block of the transverse distribution arrangement. The additional plate may have a positive effect on the segregation of the paving material in the region of the center bearing block. The additional plate may reduce the space behind the center bearing block, in particular by adjusting it in the drive direction or horizontally. By adjusting the additional plate, the horizontal distance between the additional plate and the center bearing block may be adjusted. The additional plate may prevent or reduce cooling of the paving material in the region behind the center bearing block. The additional plate metal may have elongated holes. The elongated holes may extend in the drive direction or horizontally.

According to a second aspect of the disclosure, a method for operating a road paver comprises conveying paving material against a drive direction of the road paver in front of a screed of the road paver and distributing the paving material in front of the screed transversely to the drive direction of the road paver by means of a transverse distribution arrangement. Wherein the road paver has a pre-scraper blade, which is arranged behind the transverse distribution arrangement in the drive direction and is arranged transversely to the drive direction in the region of a base screed of the screed. The pre-scraper blade may be moved in height and/or rotated during operation of the road paver, in particular during a paving run of the road paver. The road paver may be adapted according to the first aspect of the disclosure.

The pre-scraper blade may be adapted like the height-adjustable pre-scraper blade described in relation to the first aspect of the disclosure. The road paver may have a pre-scraper arrangement comprising, in particular, the pre-scraper blade. The pre-scraper arrangement may be adapted like the pre-scraper arrangement described in relation to the first aspect of the disclosure.

The height of the pre-scraper blade may be adjusted automatically by a control unit. The pre-scraper blade may be moved in height by an operator input. The control unit may be adapted like the control unit described in relation to the first aspect of the disclosure.

The method may further comprise measuring the height of the paving material in a region between the transverse distribution arrangement and the screed, in particular in a region between the pre-scraper blade and the screed. The method may further comprise adjusting the height or vertical position of the pre-scraper blade based on the measured height of the paving material.

The height or vertical position of the pre-scraper blade may be adjusted based on the current working width of the screed or a change in the working width of the screed.

The measurement of the height of the paving material may occur by means of a measuring system. The measuring system may be adapted like the measuring system described in relation to the first aspect of the disclosure.

As an alternative or in addition to adjusting the height of the pre-scraper blade, the method may comprise rotating the pre-scraper blade about an axis parallel to the drive direction. The rotation of the pre-scraper blade may occur based on the measured height of the paving material. The rotation of the pre-scraper blade may occur based on the current working width of the screed or a change in the working width of the screed.

The method may comprise adjusting the height or vertical position of a first pre-scraper blade and a second pre-scraper blade. The method may comprise adjusting a rotation of a first pre-scraper blade and a second pre-scraper blade.

The road paver according to the first aspect of the disclosure may be used with method steps of the method according to the second aspect of the disclosure. The method according to the second aspect of the disclosure may be performed with a road paver according to the first aspect of the disclosure.

As used in the description of the various embodiments described and the appended claims, the singular forms are to be understood to include the plural forms and vice versa, unless the context clearly indicates otherwise.

The expressions “first”, “second”, “third” and “fourth” are to be understood merely as determining a particular element or component and do not necessarily indicate a particular order or assembly of said components or elements. For example, the presence of a fourth element does not necessarily imply the presence of a first, second or third element and vice versa.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, advantageous embodiments of the disclosure are explained in more detail with reference to the attached figures.

FIG. 1 shows a side view of a road paver according to the disclosure.

FIG. 2 shows a perspective view of a road paver according to the disclosure.

FIG. 3 shows a top view of the longitudinal conveyor device, the transverse distribution arrangement and the screed of a road paver according to the disclosure.

FIG. 4 shows a top view of an alternative embodiment according to the disclosure of the screed shown in FIG. 3.

FIG. 5 shows a side sectional view of a section of a road paver according to the disclosure.

FIG. 6 shows a perspective view of the pre-scraper arrangement, the transverse distribution arrangement and the deflector plate arrangement of a road paver according to the disclosure.

FIG. 7 shows a perspective view of an alternative embodiment according to the disclosure of the deflector plate arrangement shown in FIG. 6.

FIG. 8 shows a perspective view of a further alternative embodiment according to the disclosure of the pre-scraper arrangement shown in FIG. 6.

FIG. 9 shows a side sectional view of a section of a road paver according to the disclosure in a first position.

FIG. 10 shows a side sectional view of a section of a road paver according to the disclosure in a second position.

FIG. 11 shows a side sectional view of a section of a road paver according to the disclosure in a third position.

FIG. 12 shows a perspective view from the side of a section of a road paver according to the disclosure.

FIG. 13 shows a perspective view from below of the section shown in FIG. 12 of a road paver according to the disclosure.

DETAILED DESCRIPTION

FIGS. 1 and 2 show a side view and a perspective top view of a road paver 1 according to the disclosure for producing a paving layer 2 on a ground 3. The road paver 1 has a material hopper 4 at the front in the paving drive direction 100, from which a paving material 6 received therein is transported to a screed 7 of the road paver 1 against the paving drive direction 100 of the road paver 1 by means of a longitudinal conveyor device 5. The longitudinal conveyor device 5 is arranged within a chassis 8 of the road paver 1 and first transports the paving material 6 to a transverse distribution arrangement 9 arranged in front of the screed 7 in the paving drive direction 100. The transverse distribution arrangement 9 is adapted to distribute the paving material 6 in front of the screed 7 along a transverse direction 200 transverse to the paving drive direction 100.

The extension of the paving layer 2 in the transverse direction 200 is referred to as the working width 210 or paving width 210. The screed 7 has a screed base or base screed 10 and laterally extendable extension screed parts 11. The working width 210 of the paving layer 2 may be varied and adjusted by extending the extension screed parts 11 sideways.

The road paver 1 also has a control unit 37. The control unit 37 may be operated by user input or automatically. The control unit 37 is adapted to adjust the vertical position of a height-adjustable pre-scraper blade 30. The control unit 37 is configured to move the height-adjustable pre-scraper blade 30 in height.

FIG. 3 shows a schematic top view of the screed 7 and the longitudinal conveyor device 5 of the road paver 1 according to the disclosure. The longitudinal conveyor device 5 has a conveyor belt in the form of a scraper belt 12. The scraper belt 12 comprises a left scraper belt section 13a and a right scraper belt section 13b. The designations left and right are to be understood as looking in the paving drive direction 100.

The paving material 6 dropped in front of the screed base body 10 of the screed 7 by means of the scraper belt 12 is distributed along a front side 14 of the screed base body 10 by means of the transverse distribution arrangement 9, as shown by arrows 220.

A rear wall 15 of the chassis 8 of the road paver 1 together with the front side 14 of the screed base body 10 forms a transverse distribution channel 16, also referred to as a screw chamber, for the transverse distribution arrangement 9.

The extension screed parts 11 of the screed 7 may be extended laterally in the transverse direction 200 relative to base screed body 10, allowing the screed 7 to be widened and the working width 210 to be varied. The transverse distribution channel 16 may be further extended laterally in accordance with a widening of the screed 7.

The paving material 6 is transferred from the scraper belt 12 of the longitudinal conveyor 5 to the transverse distribution arrangement 9, which is positioned in front of the screed 7. The transverse distribution arrangement 9 is adapted to distribute the paving material 6 in front of the screed 7 in the transverse direction 200 transverse to the paving drive direction 100 within the transverse distribution channel 16.

The transverse distribution arrangement 9 is attached to the rear end of the chassis 8 of the road paver 1. The transverse distribution arrangement 9 comprises a left distribution screw 17 and a right distribution screw 18. The left distribution screw 17 and the right distribution screw 18 are supported on a suspension 19 in the form of a screw suspension 19. The screw suspension 19 may also be referred to as a center bearing block 19.

The housing formed by the screw suspension 19 contains a worm drive (not shown) for powering the two distribution screws 17, 18. The transverse distribution arrangement 9 comprises a shaft 20, which may be two individual shafts 20 (left shaft 21, right shaft 22) or one shaft 20 that is shared by the two distribution screws 17, 18. The left screw 17 is detachably coupled to the left shaft 21. The right distribution screw 18 is detachably coupled to the right shaft 22. The outer end of each shaft 21, 22, i.e., the end facing away from the screw suspension 19, is supported in a screw bearing 23.

The pre-scraper arrangement 24 according to the disclosure is not shown in FIG. 3. The position of the pre-scraper arrangement 24 is indicated by the reference sign 24.

In the embodiment shown in FIG. 3, the front edge 14 of the base screed body 10 is arranged in front of the front edges 25 of the extension screed parts 11 in the drive direction 100. This form of screed 7 is referred to as a rearmount screed or rear screed.

FIG. 4 shows a top view of an alternative embodiment of a screed 7 of a road paver 1 according to the disclosure. In comparison to the embodiment in FIG. 3, the front edges 25 of the extension screed parts 11 are arranged in front of the front edge 14 of the base screed 10 in the drive direction 100. This form of screed 7 is referred to as a front-mount screed or front screed.

The extension screed parts 11 are in the extended position in the illustration shown in FIG. 4. The transverse distribution arrangement 9 and the pre-scraper arrangement 24 according to the disclosure are not shown in FIG. 4. The position of the transverse distribution arrangement 9 is indicated in the transverse distribution channel 16.

The road paver 1 may have a deflector plate arrangement 26, which is arranged in the drive direction 100 between the longitudinal conveyor device 5 and the transverse distribution arrangement 9. The deflector plate arrangement 26 may have a height-adjustable deflector plate.

FIG. 5 shows a side sectional view of a section of a road paver 1 according to the disclosure. The screw suspension 19 of the transverse distribution arrangement 9 is attached to the chassis 8 in a height-adjustable manner via a cylinder 27. The paving material height 28 of the paving material 6 is shown in dashed lines in FIG. 5.

The pre-scraper arrangement 24 is attached to the chassis 8 or to the screw suspension 19 via a bracket 29. Alternatively, the bracket 29 may be attached to the screed 7. The pre-scraper arrangement 24 has a pre-scraper blade 30. The pre-scraper blade 30 is adapted to move up and down relative to the bracket 29 in the vertical direction 300.

FIG. 6 shows a perspective view of the pre-scraper arrangement 24, the transverse distribution arrangement 9 and the deflector plate arrangement 26 of a road paver 1 according to the disclosure. The deflector plate arrangement 26 is optional.

The pre-scraper arrangement 24 has a support structure 31. The support structure 31 is mounted on the screw suspension 19. The pre-scraper blade 30 is mounted on the support structure 31 via an adjustment device 32 in the form of a hydraulic or pneumatic cylinder. The adjustment device 32 may be used to adjust the vertical position of the pre-scraper blade 30.

FIGS. 7 and 8 show perspective views of alternative embodiments of the pre-scraper arrangement 24 shown in FIG. 6.

The pre-scraper arrangement 24 shown in FIG. 7 has a pre-scraper blade 30 which is adapted to be rotatable by an angle 400 about an axis parallel to the drive direction 100. The rotation of the pre-scraper blade 30 may be achieved by the adjustment device 32. In particular, the adjustment device 32 has a left actuating element 33 and a right actuating element 34, which may be controlled separately from one another, in particular by the control unit 37.

The pre-scraper arrangement 24 shown in FIG. 8 has a first height-adjustable pre-scraper blade 35 in the form of a left pre-scraper blade 35 and a second height-adjustable pre-scraper blade 36 in the form of a right pre-scraper blade 36. The left pre-scraper blade 35 and the right pre-scraper blade 36 may be moved in height independently of one another. As a result, a vertical offset 310 may be achieved between the left pre-scraper blade 35 and the right pre-scraper blade 36. In particular, the adjustment device 32 has a left actuating element 33 and a right actuating element 34, which may be controlled separately from one another, in particular by the control unit 37. The vertical offset 310 between the left pre-scraper blade 35 and the right pre-scraper blade 36 is achieved by the separate control of the left actuating element 33 and the right actuating element 34.

Alternatively or in addition to the height adjustment, the left pre-scraper blade 35 and the right pre-scraper blade 36 may be adapted to be rotatable about axes extending parallel to the drive direction 100. The left pre-scraper blade 35 may be adapted to be rotatable by a first angle 410 about a first axis parallel to the drive direction 100. The right pre-scraper blade 36 may be adapted to be rotatable by a second angle 420 about a second axis parallel to the drive direction 100. The rotation of the left pre-scraper blade 35 may be achieved by the left actuating element 33. The rotation of the right pre-scraper blade 36 may be achieved by the right actuating element 34. The adjustment device 32 may have further actuating elements, in particular a second left actuating element and a second right actuating element, which are adapted to rotate the left and right pre-scraper blades, respectively. The control unit may be adapted to rotate the left pre-scraper blade 35 and the right pre-scraper blade 36 by the same angle. The control unit may be adapted to rotate the left pre-scraper blade 35 and the right pre-scraper blade 36 by different angles, in particular in different directions.

FIGS. 9 to 11 show side sectional views of a section of a road paver 1 according to the disclosure. The road paver 1 has a measuring system (no reference sign). The measuring system comprises a sensor 38. The sensor 38 is arranged between the transverse distribution arrangement 9 and the screed 7, in particular between the height-adjustable pre-scraper blade 30 and the base screed 10. The sensor 38 is aligned downwards and configured to measure the vertical distance between the sensor 38 and an upper edge of the paving material 6. Using the measured distance and the position of the sensor 38, the paving material height 28 below the sensor 38 may be determined by the sensor 38 and/or the control unit 37. The road paver 1 may also have several sensors 38.

The distribution screw height 320 of the distribution screw 17 is defined as the vertical distance from the distribution screw rotation axis 39, which extends in the transverse direction 200, and the ground 3. The paving material height 28 between the height-adjustable pre-scraper blade 30 and the base screed 10 is shown with the reference sign 330 and is defined as the vertical distance between the upper edge of the paving material 6 and the ground 3. The screed height 340 is defined as the vertical distance between the screed 7, in particular the base screed 10, and the ground 3.

In FIG. 9, the transverse distribution arrangement 9 is arranged in a first position at a first distribution screw height 320 above the ground 3. The screed 7 is arranged in a first position at a first screed height 340 above the substrate 3. The required amount of paving material 6 upstream of screed 7 or a target value for the paving material height 330 upstream of screed 7 may be determined by the control unit 37, for example based on the distribution screw height 320 and the screed height 340. Alternatively, the target value for the paving material height 330 upstream of screed 7 may occur by user input. The control unit 37 then compares the target value for the paving material height 330 with the paving material height 330 measured by the sensor 38. Based on a possible difference between the target value and the measured value, the vertical position of the height-adjustable pre-scraper blade 30 is then adjusted.

In FIG. 10, the transverse distribution arrangement 9 is arranged in the first position (as shown in FIG. 9). The screed 7 is arranged in a second position at a second screed height 340 above the base 3. The screed height 340 in FIG. 10 is greater than the screed height 340 in FIG. 9. Compared to the first position of the pre-scraper blade 30 shown in FIG. 9, the height-adjustable pre-scraper blade 30 is moved vertically upwards and is in a second position, which feeds to a greater screed height 330 in front of the screed 7. Due to the greater paving material height 330 in front of the screed 7, more paving material 6 is available in front of the screed 7, which is necessary for a greater screed height 340.

In FIG. 11, the screed 7 is arranged in a second position (as shown in FIG. 10) at a second screed height 340 above the ground 3. The transverse distribution arrangement 9 is arranged in a second position at a second distribution screw height 320 above the ground 3. The distribution screw height 320 in FIG. 11 is higher than the distribution screw height 320 in FIGS. 9 and 10. Compared to the second position of the pre-scraper blade 30 shown in FIG. 10, the height-adjustable pre-scraper blade 30 is moved vertically upwards and is in a third position, which feeds to a greater screed height 330 in front of the screed 7.

FIG. 12 shows a side sectional view of a section of a road paver according to the disclosure. FIG. 13 shows a perspective view from below of the section shown in FIG. 12. In contrast to FIG. 13, the left distribution screw 17 and the right distribution screw 18 are not shown in FIG. 12. The center bearing block 19 or the screw suspension 19 of the transverse distribution arrangement 9 is arranged between the deflector plate arrangement 26 and the pre-scraper blade 30 in the drive direction 100. An additional plate 40 is arranged at the front of the pre-scraper blade 30. The additional plate 40 is arranged between the pre-scraper blade 30 and the center bearing block 19. Viewed in the transverse direction 200, the additional plate 40 is arranged in the region of the center bearing block 19. The side of the additional plate 40 facing the center bearing block 19 may be aligned largely vertically. The additional plate 40 may be adapted to be adjustable in the drive direction 100 or horizontally. This may be achieved, for example, by elongated holes 41 in the additional plate 40. The elongated holes 41 extend in particular in the drive direction 100 or horizontally. By adjusting the additional plate 40, the distance, in particular the horizontal distance, between the additional plate 40 and the center bearing block 19 may be adjusted. The additional plate 40 is attached to the pre-scraper blade 30 by fastening means 42, for example screws and nuts. The fastening means 42 extend through the elongated holes 41 in the additional plate 40. The position of the fastening means 42 in the elongated holes 41 may be used to adjust the position of the additional plate 40 in the drive direction 100.

As one skilled in the art would understand, the above-mentioned control unit 37, measuring system, as well an any other control system, system, unit, controller, sensor (e.g., sensor 38), detector, device, component, subsystem, arrangement, or the like described herein may individually, collectively, or in any combination comprise appropriate circuitry, such as one or more appropriately programmed processors (e.g., one or more microprocessors including central processing units (CPU)) and associated memory which may include stored operating system software and/or application software executable by the processor(s) for controlling operation thereof and/or for performing the particular algorithms represented by the various functions and/or operations described herein, including interaction and/or cooperation between any such control unit 37, measuring system, control system, system, unit, controller, sensor, detector, device, component, subsystem, arrangement, or the like. One or more of such processors, as well as other circuitry and/or hardware, may be included in a single component (e.g., an ASIC (Application-Specific Integrated Circuit)), or several processors and various circuitry and/or hardware may be distributed among several separate components, whether individually packaged or assembled into a SoC (System-on-a-Chip).