Screed device for road paver

Abstract

The invention relates to a screed device (4) for a road paver (1), comprising a base screed, a first extension screed (5) and a second extension screed (6), the first and second extension screeds (5, 6) being arranged in front of the base screed (7) in a pulling direction (Z) of the screed device (4) and being movable relative to the base screed (7) transversely to the pulling direction (Z), wherein at least one of the two extension screeds (5, 6) comprises a material deflecting member (10, 10”), which is configured to move paving material transversely to the pulling direction (Z) of the screed device (4) when the extension screed (5, 6) is stationary relative to the base screed (7), wherein the first extension screed (5) comprises a material deflecting member (10, 10”), wherein the second extension screed (6) is positioned further away from the base screed (7) in the pulling direction (Z) than the first extension screed (5).

Description

TECHNICAL FIELD

[0001] The invention relates to a screed device for a road paver. BACKGROUND

[0002] A road paver for paving concrete or asphalt paving mixture usually has a screed device trailing behind the road paver. This screed device makes the spread paving mixture even and pre-compacts it to a considerable extent before final compaction, for example by a road roller following the road paver. It is particularly advantageous if the screed has a variable length in a direction transverse to the paving travel direction of the road paver in order to be able to achieve different paving widths.

[0003] EP 2 201 176 B1 discloses a screed having telescoping sections arranged one after the other, which are firmly connected to a fixed section.

[0004] The unpatented EP 2 395 151 A1 discloses a screed device having one base screed and two extension screeds arranged in front of the base screed in the paving travel direction, which can be extended and retracted transverse to the paving travel direction in one common adjustment plane. This screed device is also known among experts as "front-mounted screed". Since both extension screeds are directly adjacent to the front of the base screed, a material deflection member can be provided on the base screed and / or at least one extension screed, which can be adjusted relative thereto, in order to prevent paving material from being jammed between the two extension screeds when the two extension screeds are moved towards each other and the predetermined distance between the two extension screeds falls below a certain value.

[0005] However, this screed device has the disadvantage that the working width of the extension screeds in a direction transverse to the paving travel direction is limited to approximately half the working width of the base screed. Thus, the maximum paving width cannot exceed twice the working width of the base screed. Therefore, for road construction with a larger paving width, additional bolted-on extensions have to be added to the screed device, which in turn is time-consuming and laborious. SUMMARY

[0006] It is an object of the invention to provide a screed device for a road paver in order to eliminate the above-mentioned disadvantages.

[0007] This object is solved by a screed device according to the invention. Advantageous further embodiments of the invention are indicated in the invention.

[0008] The invention relates to a screed device for a road paver, having a base screed, a first extension screed and a second extension screed, the first and second extension screeds being arranged in front of the base screed in the towing direction of the screed device and being movable relative to the base screed transversely to the towing direction, wherein at least one of the first and second extension screeds comprises a material deflection member configured to move paving material towards a central axis in the towing direction of the screed device when the extension screed is stationary relative to the base screed, the first extension screed comprising the material deflection member, the second extension screed being positioned further away from the base screed in the towing direction of the screed device. Furthermore, the base screed for the first extension screed comprises a shielding element or deflection plate or shield plate. The shielding element can be understood in the broadest sense as a wall. The shielding element is configured to prevent paving material located in front of the base screed from moving transversely beyond the width of the base screed when the first extension screed is retracted. The towing direction of the screed device is the direction in which the screed device is towed by the road paver or its towing machine during operation, i.e. it corresponds to the direction of travel of the road paver.

[0009] One of the main advantages of the screed device according to the invention is the high variability of the paving width. This is because the extension screeds arranged one after the other in the towing direction in the invention can each have a working width that is substantially the same as that of the base screed. Thus, according to the invention, the maximum paving width of the screed device can be about three times the working width of the base screed when both extension screeds are in the maximum extended position, and this without the addition of any additional bolt-on extensions. This speeds up the adjustment of the paving width, especially on site, since there is no need to install, dismount or adjust bolt-on extensions.

[0010] Another advantage of the extension screeds being arranged one after the other in the towing direction in a staggered manner is that this arrangement makes it possible for little or even no paving material to become jammed between two extension screeds, since they do not move towards each other in the same displacement plane during retraction. Furthermore, the material deflection member of the first extension screed allows the paving material to be moved towards the central axis in the towing direction of the screed device, so that no paving material becomes jammed between the extension screed and the shielding member of the base screed when this extension screed is retracted. The shielding element can prevent paving material located in front of the base screed from being pushed onto the road bed beyond the width of the base screed or onto a pavement that has already been pre-compacted by the extension screed working in the foremost position when the first extension screed is retracted.

[0011] Conveniently, the screed device has a central axis parallel to the traction direction, each extension screed has an inner side and an outer side, in the extended position of the respective extension screed the inner side is closer to the central axis than the outer side, the material deflection means are arranged on the inner side of the extension screed.

[0012] Preferably, the base screed and the two extension screeds have substantially the same working width. As already indicated above, this allows the screed device to achieve a significantly greater paving width compared to known screed devices in which the extension screeds are half the size of the base screed.

[0013] It is particularly useful if the shielding element is in the form of a plate laterally attached to the base screed body of the base screed and extending beyond the base screed body in the traction direction. This allows the first extension screed to be retracted and extended over its entire working width.

[0014] It can be particularly effective to prevent the paving material from falling transversely to the traction direction if the shielding element is formed substantially as high as the first extension screed and / or if the shielding element extends in the traction direction by a depth corresponding to the working depth of the first extension screed.

[0015] In an advantageous embodiment, the shielding element is formed adjustable and / or detachable with respect to the base screed in the traction direction. This allows the shielding element to be adjusted based on the structural configuration of the material deflection means. A detachable shielding element facilitates cleaning and possible transport purposes.

[0016] The shielding element or parts formed thereon can conveniently be formed pivotable with respect to the base screed and / or movable transversely to the traction direction. In this way, the paving material can be moved from the outer area in front of the base screed inwardly towards the central axis of the screed device travelling in the traction direction.

[0017] In an alternative embodiment, the shielding element is formed as part of a side shift device of the base screed. Such a side shift device prevents the paving material from falling beyond the desired width. In addition to its actual function, it also acts as a shielding element.

[0018] It is conceivable that the shielding element is arranged as a plate on a side shift device of the base screed. The plate can be formed displaceable or pivotable with respect to the side shift device in order to push the paving material in the direction of the central axis of the screed device. This would allow the paving material to be moved in such a way that it is not jammed between the two extension screeds when the extension screeds are retracted. In this case, it is conceivable that the two extension screeds are retracted one after the other, i.e. the one positioned closer to the base screed is retracted first, while the extension screed positioned in front of it is at least temporarily offset.

[0019] In a particularly stable embodiment, the shielding element is formed as an integral part of the side shift device of the base screed.

[0020] By allowing the material deflecting member and / or the shielding element to be heated, it is possible to particularly effectively reduce the jamming or sticking of the paving material.

[0021] It is particularly advantageous for moving the paving material if the second extension screed also has a material deflecting member configured for moving the paving material. It is advantageous if the first extension screed has a shielding element for the material deflecting member of the second extension screed. At least in terms of functionality, the previously described structure of the shielding element of the base screed and the material deflecting member of the first extension screed is repeated in this variant. Basically, both the shielding element and the material deflecting member can be formed in a similar manner.

[0022] The side shift device of the first extension screed arranged on the opposite side of the material deflecting member formed on the first extension screed can act as a shielding element for the material deflecting member formed on the second extension screed.

[0023] It is conceivable to provide the side shift device of the first extension screed with a shielding element that is adjustable, in particular pivotable or movable, with respect to the side shift device formed thereon, in order to facilitate the movement of the paving material in the direction of the central axis of the screed device.

[0024] The screed device is particularly stable if the material deflecting member is rigidly formed on the respective extension screed.

[0025] It is conceivable that the material deflecting member is adjustable between an inactive position, in which it extends parallel to the direction of traction, and an active position, in which it extends at an angle to the direction of traction. In the inactive position, the material deflecting member thus does not influence the paving process. In addition, in the inactive position, the extension screed can use an additional working width. In the active position, the positioning of the material deflecting member at an angle to the direction of traction ensures that the paving mixture moves towards the central axis of the screed device when the extension screed is retracted. The deflection of the paving material, i.e. the case of the paving material moving towards the central axis of the screed device, becomes particularly effective when the material deflecting member is arranged in the active position at an angle of 30° to 55° with respect to the direction of traction. The material deflecting member can be pivoted about a hinge. The trailing side of the material deflecting member can also be coupled to the base screed by a sliding fit, so that the trailing side can be moved along the base screed.

[0026] The deflection of the paving material is particularly effective if the material deflecting member is configured in the form of a plow structure. This allows the paving material to be pushed ahead when the extension screed is retracted.

[0027] If the material deflecting member extends in a plan view at a non-zero angle with respect to the direction of traction, preferably at an angle of 30° to 60°, the deflection of the paving material is particularly effective.

[0028] It is particularly convenient if the screed device has a screed operating station on the side of the base screed facing the material deflecting member of the first extension screed. From here, the screed operator has a good view of the material deflecting member, in particular during the plough function of the extension screed.

[0029] Finally, the invention relates to a road paver having a screed device of the above-mentioned type. Such a road paver, and in particular the screed device applied thereto, enables a paving width to be adjusted quickly and precisely without the mixture becoming jammed between the base screed and the extension screed. Furthermore, the screed device offers the practical advantage of being able to be adjusted quickly and precisely for levelling purposes, in particular for height and transverse slope levelling. This is firstly due to the widely adjustable screed structure of the screed device according to the invention, which, however, is composed of a small number of modules. BRIEF DESCRIPTION OF DRAWINGS

[0030] In the following, advantageous embodiments of the invention are explained in more detail with reference to the drawings.

[0031] Figure 1 A side view of a road paver is shown,

[0032] Figure 2 A screed device according to the invention is shown in a schematic view,

[0033] Figure 3 A screed device according to the invention is shown when the extension screed is extended,

[0034] Figure 4 A screed device according to the invention is shown, wherein the extension screed is in the extended position,

[0035] Figure 5 A perspective view of the extension screed is shown separately,

[0036] Figure 6 A schematic, diagrammatic variant of a screed device according to the invention is shown, wherein the extension screed is in the extended position,

[0037] Figure 7 Another variant of a schematic, diagrammatic representation of a screed device according to the invention is shown, wherein the extension screed is in the extended position.

[0038] In all the figures, identical parts are marked with the same reference symbols. DETAILED DESCRIPTION

[0039] Figure 1 A side view of a road paver 1 is shown, the paving direction of which is indicated by E. The road paver 1 comprises a tractor 2 having a mix hopper 3 into which, for example, asphalt mix can be poured. The mix or paving material can be conveyed by a conveyor system (not shown) to the rear end of the tractor 2 against the paving travel direction E of the road paver 1. There, it can be distributed transversely to the paving travel direction E in front of a screed device 4 of the road paver 1. The screed device 4 can be mounted in a horizontally movable manner on the tractor 2 by means of a support arm 20. The screed device 4 is towed behind the tractor 2 of the road paver 1 in the paving travel direction E.

[0040] Between the tractor 2 of the road paver 1 and the towed screed device 4, there is a transverse spreading device 18 (see Figure 2 , for example two transverse spreading augers, for spreading the paving material to be processed in front of the screed device 4 over the entire paving width. The screed device 4 serves, inter alia, for smoothing and / or pre-compacting the mix.

[0041] In Figure 1 , the road paver 1 is shown as a wheeled paver. Alternatively, the road paver 1 can have a tracked chassis.

[0042] Figure 2 An embodiment of a screed device 4 according to the application is shown. The screed device 4 is of the "front-mounted screed" type, in which, viewed in the towing direction Z of the screed device 4, a first extension screed 5 and a second extension screed 6 are arranged in front of a base screed 7. The towing direction Z of the screed device 4 corresponds to the paving travel direction E of the road paver 1. The first extension screed 5 is positioned closer to the base screed 7 in the towing direction Z. The second extension screed 6 is positioned further away from the base screed 7 in the towing direction Z than the first extension screed 5. The first extension screed 5 and the second extension screed 6 are thus arranged one behind the other in the towing direction Z, i.e. not in the same plane. The base screed 7 can be a single piece or consist of multiple parts. Figure 2 Each of the screed parts shown in

[0043] Figure 2The retracted positions of the two extension screeds 5 and 6 are shown. In the direction transverse to the traction direction Z, the base screed 7 and the two extension screeds 5 and 6 all have substantially the same working width 16. To obtain a greater paving width, the extension screeds 5 and 6 can be moved relative to the base screed 7 in the extension direction A, i.e., transverse to the traction direction Z. Suitable drive and guidance systems, such as hydraulic drives, guide rails, and / or guide rods, are provided for extending and retracting the extension screeds 5 and 6.

[0044] A material deflection member 10 is formed on the inner side 9 of the first extended ironing plate 5, which in Figure 2 The base ironing plate 7 is wedge-shaped and integrally formed with the extension ironing plate body 5' of the first extension ironing plate 5. The base ironing plate 7 has a shielding element 13 for the first extension ironing plate 5. The shielding element 13 is provided laterally on the base ironing plate body 7'. For example, it can be mounted as a rigid plate 13''', possibly as part of a lateral displacement device formed on the base plate 7. The shielding element 13 forms a wall extending in the traction direction Z.

[0045] When the extension screed 5 is retracted, the material deflection member 10 allows the paving mix to shift from area 12 of the screed assembly 4. This prevents the paving material from getting stuck between the shielding element 13 of the base screed 7 and the immediately preceding extension screed 5. When the extension screed 5 is retracted in front of the base screed 7, the shielding element 13 prevents the paving material from spreading laterally beyond the width of the base screed 7. Lateral shifting devices 5a and 6a are provided on the outer side 11 of each extension screed 5, 6, which substantially determine the paving width of the new road paving and prevent the paving mix from spreading beyond the desired width.

[0046] Figure 3 The screed assembly 4 is shown during the extension of the screeds 5 and 6 in the extension direction A to produce a greater paving width.

[0047] exist Figure 3 In the illustrated embodiment, the second extended screed 6 also has a material deflection member 10' on its inner side 9'. In this embodiment, the material deflection member 10' is wedge-shaped and integrally formed with the extended screed body 6' of the second extended screed 6. When the second extended screed 6 is retracted, the material deflection member 10' allows the paving mix to shift from the area 12' of the screed device 4. This prevents the paving material from getting stuck between the lateral displacement device 5a of the extended screed 5 and the extended screed 6.

[0048] Figure 4The screed device 4 is shown in the extended position 17. As shown, each extension screed 5, 6 has a side shift device 5a, 6a at its outer side 11 and a material deflecting member 10, 10' at its inner side 9. The extended extension screeds 5, 6 allow a total working width 16' which is substantially three times the working width which can be produced by the base screed 7 alone.

[0049] Figure 4 The variant shown in dashed lines provides a first shielding element 13 which is attached laterally to the base screed 7 so that it can be pivoted by a hinge 19. A hydraulic drive (not shown) can be provided for this purpose. In a first position 13', the shielding element 13 is mounted substantially parallel to the direction of traction Z. When the screed 5 is retracted, i.e. when the first screed 5 is moved in the retraction direction A', the shielding element 13 prevents paving mixture or paving material from falling out of the area 12 of the screed device 4. In a second position 13'' shown in dashed lines, the shielding element 13 is aligned at an angle a of 30° to 55° with respect to the direction of traction Z in order to move the paving material in the direction of the (virtual) centre axis M of the screed device 4. The shielding element 13 is preferably formed as high as the first extension screed 5. The shielding element 13 extends in the direction of traction Z by a depth 15 which corresponds to the working depth of the first extension screed 5.

[0050] Figure 4 It is also shown that the first extension screed 5 has a shielding element 14 for the second extension screed 6. When the extension screed 6 is retracted, the shielding element 14 prevents paving material spread in front of the extension screed 5 from being pushed beyond the width of the extension screed 5. The shielding element 14 is provided on one side of the extension screed 5'. It can be mounted, for example, as a rigid plate 14''' which can be provided as part of the side shift device 5a formed on the extension screed 5. The shielding element 14 forms a wall which extends in the direction of traction Z.

[0051] Furthermore, Figure 4 A variant is indicated in dashed lines according to which the shielding element 14 is pivotally mounted on the side shift device 5a of the first extension screed 5 by a hinge 19' with respect to the side shift device 5a in order to further facilitate the movement of paving material from the area 12' of the screed device 4 during retraction of the second extension screed 6 in the retraction direction A'. The shielding element 14 can be provided between a first position 14' and a second position 14'' by a hydraulic actuator (not shown). In the first position 14', the shielding element 14 is substantially parallel to the direction of traction Z. In the second position 14'', the shielding element 14 is aligned at an angle a of 30° to 55° with respect to the direction of traction Z in order to move the paving material in the direction of the centre axis M of the screed device 4 when the screed device 4 is being towed by the road paver in the direction of traction Z.

[0052] Figure 4It is shown that the material deflection member 10 together with the shielding element 13 and the material deflection member 10' together with the shielding element 14 form a functional unit on the screed device 4, which can prevent the paving material from getting stuck between the shielding element 13 of the base screed 7 and the extension screed 5, and between the side shift device 5a of the extension screed 5 and the further extension screed 6. These functional units thus have a mirror-symmetrical structure offset in the traction direction Z with respect to the central axis M.

[0053] Figure 5 It is shown that the extension screeds 5, 6 are shown in perspective, wherein the working depth 15 and the working height 21 of the extension screeds 5, 6 are shown.

[0054] Figure 6 It is shown that another embodiment of the screed device 4 is shown, wherein the extension screeds 5, 6 are in the extended position 17, wherein each extension screed 5, 6 has a material deflection member 10, 10', and wherein a shielding element 22, 22' movably arranged with respect to the respective side shift device 5a, 7a is provided on the side shift device 7a of the base screed 7 and on the side shift device 5a of the first extension screed 5.

[0055] Figure 7 It is shown that another embodiment of the screed device 4 is shown, wherein the extension screeds 5, 6 are in the extended position 17, wherein each extension screed 5, 6 has a material deflection member 10'', 10''' pivotable with respect to the respective extension screed body 5', 6'. The material deflection members 10'', 10''' are pivotable about hinges 23, 23'. For this purpose, respective hydraulic drive devices (not shown) can be provided.

[0056] In the shown embodiments, the respective material deflection members 10, 10', 10'', 10''' and / or the shielding elements 13, 14, 22, 22' can be formed as heating plates, in particular electric heating plates.

[0057] Figures 2-4 , 6 and 7 shows the screed operating station B located on one side of the base screed 7. The screed operating station B is positioned to face the first extension screed 5, in particular the area 12.

Claims

1. A screed assembly (4) for a road paver (1), comprising a base screed (7), a first extension screed (5), and a second extension screed (6), the first extension screed (5) and the second extension screed (6) being arranged in front of the base screed (7) in the traction direction (Z) of the screed assembly (4) and being movable transversely to the traction direction (Z) relative to the base screed (7), wherein at least one of the first extension screed and the second extension screed (5, 6) includes a material deflection member configured to move paving material toward the central axis (M) along the traction direction (Z) of the screed assembly (4) when the extension screed (5, 6) is stationary relative to the base screed (7). Its features The first extension ironing plate (5) includes a material deflection member, and the second extension ironing plate (6) is positioned in the traction direction (Z) further away from the base ironing plate (7) than the first extension ironing plate (5), wherein the base ironing plate (7) includes shielding elements (13, 22) configured to prevent paving material located in front of the base ironing plate (7) from lateral movement beyond the width of the base ironing plate (7) during the retraction of the first extension ironing plate (5).

2. The ironing board device according to claim 1, characterized in that, The central axis (M) is parallel to the traction direction (Z), and each extension ironing plate (5, 6) has an inner side (9) and an outer side (11), wherein in the extension position of the respective extension ironing plate (5, 6), the inner side (9) is closer to the central axis (M) than the outer side (11), wherein the material deflection member is arranged on the inner side (9) of the extension ironing plate (5, 6).

3. The ironing board device according to claim 1 or 2, characterized in that, The shielding elements (13, 22) are in the form of a plate (13”'), which is laterally fixed to the base ironing plate body (7’) of the base ironing plate (7) and extends beyond the base ironing plate body (7’) in the traction direction (Z).

4. The ironing board device according to claim 3, characterized in that, The shielding elements (13, 22) are formed to be approximately the same height as the first extended ironing plate (5), and / or the shielding elements (13, 22) extend in the traction direction (Z) corresponding to the working depth (15) of the first extended ironing plate (5).

5. The ironing board device according to claim 1 or 2, characterized in that, The shielding elements (13, 22) are configured such that they can be adjusted and / or removed relative to the base ironing plate (7) in the traction direction (Z).

6. The ironing board device according to claim 1 or 2, characterized in that, The shielding elements (13, 22) are formed as part of the lateral displacement device (7a) of the base ironing plate (7).

7. The ironing board device according to claim 1, characterized in that, The second extended screed (6) also has a material deflection member for moving paving material.

8. The ironing board device according to claim 1 or 2, characterized in that, The material deflection components and / or shielding elements (13, 22) can be heated.

9. The ironing board device according to claim 1 or 2, characterized in that, The first extended ironing plate (5) has shielding elements (14, 22') for the material deflection member of the second extended ironing plate (6).

10. The ironing board device according to claim 1 or 2, characterized in that, The material deflection component is rigidly formed on the extended ironing plate (5, 6).

11. The ironing board device according to claim 1 or 2, characterized in that, The material deflection component is adjustable relative to the extension ironing plate body (5', 6') of the extension ironing plate (5, 6).

12. The ironing board device according to claim 11, characterized in that, The material deflection member is rotatable and / or movable relative to the extension ironing plate body (5', 6') of the extension ironing plate (5, 6).

13. The ironing board device according to any one of claims 1, 2, 7 or 12, characterized in that, The material deflection component has a plow-like structure.

14. The ironing board device according to any one of claims 1, 2, 7 or 12, characterized in that, The material deflection component extends at a non-zero angle (α) relative to the traction direction (Z) in the plan view.

15. The ironing board apparatus according to any one of claims 1, 2, 7 or 12, characterized in that, The ironing plate device (4) includes an ironing plate operation station (B) that has a material deflection member that faces the base ironing plate (7) and the first extended ironing plate (5) laterally.

16. A road paver (1), comprising a screed device (4) according to any one of claims 1 to 15.

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