Abstract
A road finisher includes a lifting device which is designed to lift the chassis relative to the undercarriage at least in a rear region of the road finisher. The road finisher further comprises a material deflector, which can be pivoted relative to the chassis, and that is arranged between the two traction tracks.
Claims
1. A road finisher comprising: an undercarriage with two traction tracks; a chassis; a hopper, which is mounted on the chassis at a front of the road finisher with respect to a paving direction, for receiving paving material; a paving screed provided at a rear of the road finisher with respect to the paving direction for compacting paving material, the paving screed being attached to the chassis by pulling arms; a lifting device which is configured to lift the chassis relative to the undercarriage at least in a rear area of the road finisher; and a material deflector arranged between the two traction tracks and that is movable relative to the chassis.
2. The road finisher according to claim 1 further comprising an actuator unit configured to move the material deflector relative to the chassis.
3. The road finisher according to claim 2 wherein the actuator unit is configured to pivot the material deflector relative to the chassis.
4. The road finisher according to claim 2 further comprising a sensor unit configured to detect a distance of the chassis from a ground and/or a lifting path between the chassis and the undercarriage and/or a distance of a lower edge of the material deflector from the ground, wherein the actuator unit is configured to move the material deflector based on signals generated by the sensor unit.
5. The road finisher according to claim 2 wherein the actuator unit comprises an electric, hydraulic, electrohydraulic or pneumatic actuator.
6. The road finisher according to claim 2 wherein the actuator unit comprises an elastic element.
7. The road finisher according to claim 6 wherein the elastic element is configured to be deflected when the movement of the material deflector is blocked.
8. The road finisher according to claim 1 further comprising a sensor unit configured to detect a distance of the chassis from a ground and/or a lifting path between the chassis and the undercarriage and/or a distance of a lower edge of the material deflector from the ground.
9. The road finisher according to claim 8 wherein the sensor unit comprises a laser sensor, a radar sensor or an ultrasonic sensor.
10. The road finisher according to claim 1 wherein the lifting device comprises a rocker which is mounted rotatably about an undercarriage rotational axis on an undercarriage-side bearing surface and rotatably about a chassis rotational axis on a chassis-side bearing surface.
11. The road finisher according to claim 10 wherein the lifting device further comprises a length-adjustable adjustment element which connects a chassis-side link point to a rocker-side link point and is configured to change a distance between the chassis-side link point and the rocker-side link point by changing its length and thus selectively lift or lower the chassis relative to the undercarriage.
12. The road finisher according to claim 1 further comprising a coupling mechanism configured to move the material deflector relative to the chassis when the lifting device lifts the chassis relative to the undercarriage.
13. The road finisher according to claim 12 wherein the coupling mechanism comprises a deflection lever rotatably mounted on the chassis.
14. The road finisher according to claim 12 further comprising an actuator unit configured to move the material deflector relative to the chassis, and a sensor unit configured to detect a distance of the chassis from a ground and/or a lifting path between the chassis and the undercarriage and/or a distance of a lower edge of the material deflector from the ground, wherein the coupling mechanism comprises an open loop or closed loop control unit connected to the sensor unit and the actuator unit, and wherein the control unit is configured to actuate the actuator unit in response to signals received from the sensor unit.
15. The road finisher according to claim 12 wherein the coupling mechanism comprises an elastic element.
16. The road finisher according to claim 15 wherein the elastic element is configured to be deflected when the movement of the material deflector is blocked.
17. The road finisher according to claim 1 further comprising an undercarriage protector which is arranged in the paving direction behind one of the traction tracks.
18. The road finisher according to claim 17 wherein the undercarriage protector is concealed towards a rear side of the road finisher by the chassis in a position of the chassis which is lowered to a maximum relative to the undercarriage and can be exposed by lifting the chassis.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 shows a schematic side view of a road finisher according to an embodiment;
(2) FIG. 2 shows a schematic perspective view of the chassis and the undercarriage of the road finisher according to the embodiment;
(3) FIG. 3 shows a schematic perspective view of the rocker of a lifting device of the road finisher according to the embodiment;
(4) FIG. 4A shows a schematic side view of the undercarriage and chassis of the road finisher according to the embodiment in a maximum lowered position of the chassis;
(5) FIG. 4B shows a schematic side view of the undercarriage and chassis of the road finisher according to the embodiment in a maximum lifted position of the chassis;
(6) FIG. 5 shows a schematic perspective view of a right-hand connecting area between the undercarriage and the chassis, located at the front of the road finisher in the direction of travel in accordance with the embodiment;
(7) FIG. 6A shows a schematic perspective view of a chassis according to an embodiment with a folded-out material deflector and a coupling mechanism;
(8) FIG. 6B shows the view from FIG. 6A with the material deflector folded in.
(9) FIG. 7A shows a schematic rear view of a chassis with two undercarriages according to the embodiment from FIGS. 6A and 6B in a lifted position;
(10) FIG. 7B shows the view from FIG. 7A in a lowered position of the chassis;
(11) FIG. 8 shows a schematic representation of a coupling mechanism comprising an open loop or closed loop control unit according to another embodiment;
(12) FIG. 9A shows a schematic side view of a lowered chassis with undercarriage according to an embodiment with chassis protector;
(13) FIG. 9B shows the view from FIG. 9A with the chassis lifted relative to the undercarriage; and
DETAILED DESCRIPTION
(14) FIG. 1 shows a schematic side view of a road finisher 1 according to the disclosure according to an embodiment. The road finisher 1 comprises a chassis 3 and an undercarriage 5, in this case a crawler track. In paving direction F at the front, a hopper 7 for receiving paving material is fitted at chassis 3. On both lateral sides of road finisher 1, with regard to paving direction F, a pulling arm 9 is mounted on chassis 3 via a height-adjustable link point 11. The link point 11 can be adjusted in height at the road finisher 1 using a linkage hydraulic cylinder 13. At the rear of the road finisher 1, the pulling arms 9 are attached to both sides of the chassis 3 via height-adjustable rear hydraulic cylinders 15. A paving screed 17 for compacting paving material is suspended from the rear end of the pulling arms 9 with respect to paving direction F. During paving, the paving screed 17 is pulled by the pulling arms 9 floating on the paving material behind the road finisher 1. In the rear region of the road finisher 1, the paving material leaves conveyor device 19 through a material outlet 21 and reaches a spreading auger 23 fixed to the chassis 3 for distributing the paving material in front of paving screed 17 transversely to paving direction F. The spreading auger 23 and the material outlet 21 are concealed in FIG. 1 but shown in FIG. 2. A control station 25 is provided on the chassis 3 of the road finisher 1, which provides space for an operator and includes operating units 27 for making inputs to control the road finisher 1.
(15) FIG. 2 shows a schematic side view of the undercarriage 5 and the chassis 3 of the road finisher 1, whereby for reasons of clarity various superstructures, components and claddings provided on the chassis 3 are not shown. A lifting device 29 for lifting the chassis 3 relative to the undercarriage 5 in the rear region of the road finisher 1 is provided in a rear region of the chassis 3 with respect to the paving direction F. The lifting device 29 comprises a rocker 31 on each of the two lateral sides of the road finisher 1 as well as a length-variable adjustment element 33. In the following, the design and function of the lifting device 29 are described for only one side of the road finisher 1. The opposite side can be of the same design.
(16) The rocker 31 is rotatably mounted around an undercarriage rotation axis A at an undercarriage side bearing surface 35. As shown in FIG. 2, a track carrier 37 of the undercarriage 5 comprises a cylindrical recess 39, the inner wall of which forms the undercarriage side bearing surface 35. In the recess 39 a cylindrical extension 41 of the rocker 31 extending along the undercarriage rotation axis A is rotatably accommodated. Alternatively, it would also be conceivable that a corresponding recess would be provided in the rocker 31 and a cylindrical extension of the track carrier 37 would be rotatably accommodated in it about the undercarriage rotation axis A. In this case, the undercarriage side bearing surface 35 would be formed by the circumferential surface of the extension.
(17) In addition, the rocker 31 is mounted on a chassis-side bearing surface 43 so that it can rotate about a chassis rotation axis of B. As can be seen from the schematic view of the inner surface of the rocker 31, which is not visible in FIG. 2, as shown in FIG. 3, a cylindrical element 45, which is fixed to the chassis 3, is mounted in a corresponding recess 47 of the rocker 31 so that it can rotate about the chassis rotation axis B. The chassis-side bearing surface 43 is provided by an outer circumference of the cylindrical element 45. Alternatively, it would also be conceivable that an extension of the rocker 31 could be mounted in a corresponding recess of a chassis-fixed element so that it could rotate about the chassis rotation axis B. In this case, an inner circumferential surface of the recess would provide the chassis-side bearing surface 43.
(18) The undercarriage rotation axis A and the chassis rotation axis B are parallel to each other and run in a transverse direction perpendicular to the paving direction of travel F.
(19) As shown in FIG. 2, the first end of the length-variable adjustment element 33 is connected to a chassis-side link point 49, so that it can be rotated about a rotation axis E. A second end of the length-variable adjustment element 33 is connected to a rocker-side link point 51 so that it can be rotated about a rotation axis G. The length-variable adjustment element 33 thus connects the chassis-side link point 49 with the rocker-side link point 51. The rotation axis E and the rotation axis G are parallel to each other as well as to the chassis rotation axis A and the undercarriage rotation axis B and run in a transverse direction perpendicular to the paving direction F.
(20) In the illustrated embodiment, the length-variable adjustment element 33 is a hydraulic cylinder. However, it would also be conceivable to provide another length-variable adjustment element 33, such as a spindle drive. The length-variable adjustment element 33 can be actuated by an actuator 53 to change its length. The actuator 53 may be controlled to change the length of the length-variable adjustment element 33 using control element 55, which in the embodiment shown is an operating element in control stand 25 of road finisher 1. This can be done in particular on the basis of user input by a road finisher operator.
(21) By changing the length of the length-variable adjustment element 33 using the actuator 53, a distance between the chassis-side link point 49 and the rocker-side link point 51 is changed. This changes the position of rocker 31 in relation to undercarriage 5 and chassis 3 and thus selectively lifts or lowers chassis 3 in relation to undercarriage 5.
(22) The length-variable adjustment element 33 extends at least essentially along a horizontal direction. In the illustrated embodiment, the chassis-side link point 49 is located behind the chassis rotation axis B and the chassis rotation axis A with respect to the paving direction F. However, it would also be conceivable that the chassis-side link point 49 would be located in front of the chassis rotation axis B and/or the chassis rotation axis A with regard to paving direction F.
(23) FIG. 4A shows the chassis 3 in a maximum lowered position compared to the undercarriage 5. In the illustrated embodiment, this corresponds to a minimum length of the length-variable adjustment element 33. In the maximum lowered position of chassis 3 the chassis 3 is secured against further lowering by the engagement of the rocker 31 with a lower abutment 57 provided at chassis 3. If, from the position shown in FIG. 4A, the length of the length-variable adjustment element 33 is increased by the actuator 53, the distance between the chassis-side link point 49 and the rocker-side link point 51 increases. In the view shown in FIG. 4A, the rocker 31 is rotated clockwise about the undercarriage rotation axis A, which runs into the center of the drawing plane through the extension 41 of the rocker 31. This lifts the chassis 3 due to the bearing of the rocker 31 on the chassis-side bearing surface 43 which can be rotated around the chassis rotation axis B.
(24) If the length of the length-variable adjustment element 33 is extended further, the state shown in FIG. 4B is finally achieved. FIG. 4B shows a maximum lifted state of the chassis 3 in relation to the undercarriage 5. In this state the rocker 31 comes into engagement with an upper abutment 59 provided at the chassis 3, which prevents a further extension of the length of the length-variable adjustment element 33 and thus a further pivoting of the rocker 31 around the undercarriage rotation axis A.
(25) By again reducing the length of the length-variable adjustment element 33 the chassis 3 can be lowered again from the position shown in FIG. 4B. Preferably the height of chassis 3 can be continuously adjusted between the minimum lifted state and the maximum lifted state by suitable adjustment of the length-variable adjustment element 33. However, it would also be conceivable to provide several discrete adjustment options.
(26) As shown in FIG. 3, a locking element 61 designed as a locking bolt is provided in the illustrated embodiment for mechanically locking the rocker 31 in a defined relative position with respect to the chassis 3. The locking element 61 is provided at the chassis 3 and can be extended laterally in a horizontal plane perpendicular to the paving direction F by a locking element actuator 62 in order to engage a locking structure 63 of the rocker 31 in an extended position. In illustrated the embodiment, the locking structure 63 of the rocker 31 is designed as a recess. By locking engagement of the locking element 61 with the locking structure 63 of the rocker 31, the rocker 31 is fixed against changing its relative position in relation to the chassis 3 and the undercarriage 5. In this way, the chassis 3 can be mechanically secured at a defined height, for example at a transport position for transporting the road finisher 1 between construction sites.
(27) As shown amongst other things in FIGS. 4A and 4B, a distance d between the chassis rotation axis B and the undercarriage rotation axis A is greater than a distance e between the chassis rotation axis B and the chassis-side bearing surface 43. The undercarriage rotation axis A is therefore outside the bearing of the rocker 31 at the chassis 3. This results in an improved power transmission when lifting the chassis 3. In addition, as can be seen, the lifting device 29 can be designed to be compact.
(28) FIGS. 4A and 4B schematically illustrate the absolute value f of the part of the connection vector between the rocker-side linkage point 51 and the undercarriage rotation axis A which is perpendicular to the longitudinal extension direction of the length-variable adjustment element 33. In addition, the absolute value x of the part of the connection vector between the undercarriage rotation axis A and the chassis rotation axis B extending in a horizontal direction is shown schematically. Preferably, the ratio of these amounts, f/x, is greater than 0.5, than 0.7, than 1, than 1.3, than 1.5 or than 2. Thus, due to a leverage effect, particularly good power transmission is achieved when lifting or holding the chassis 3 by the length-variable adjustment element 33.
(29) In the illustrated embodiment, chassis 3 is mounted on undercarriage 5 in a front region of road finisher 1 with respect to paving direction F such that it can be pivoted and longitudinally displaced with respect to paving direction F. In this way, chassis 3 can be lifted or lowered in the rear region of the road finisher 1 relative to undercarriage 5 without creating tension in the front region of the road finisher 1. It is possible to lift chassis 3 asymmetrically in such a way that chassis 3 is lifted further in the rear region of the road finisher 1 than in the front region of the road finisher 1. FIG. 5 shows in a sectional schematic side view an attachment region 65 between the undercarriage 5 and the chassis 3 located on the right side of the road finisher 1. On the left side of the road finisher 1 there could be an analogous attachment region 65. The undercarriage 5 can be pivoted and is mounted on a bearing block 67 of chassis 3 so that it can be displaced longitudinally in relation to paving direction F. In particular, undercarriage 5 can be mounted at bearing block 67 using a pivoting bearing 69 with integrated sliding bearing.
(30) The view in FIG. 6A shows a chassis 3 of a road finisher 1 according to an embodiment with a material deflector 71. The latter may be provided on the chassis 3 in a movable, for example pivotable as shown in the embodiment, way. The material deflector 71 has a lower edge 73. A coupling mechanism 75 is provided for moving the material deflector 71, i.e., in the present embodiment for pivoting it. As in the present embodiment, this can be a mechanical coupling mechanism, in particular a purely mechanical coupling mechanism. In the present embodiment, the coupling mechanism comprises a deflection lever 77, which is rotatably mounted on the chassis 3. The connection lever 77 may be connected to a rod 79, which in turn can be connected to the lifting device 29, in the present embodiment to the rocker 31. The rod 79 may be adapted to transmit a movement of the lifting device 29, in particular a rotation of the rocker 31, to the deflection lever 77. The deflection lever 77 may be caused to rotate.
(31) The rod 79 may have a thread through which the length of the rod 79 can be adjusted. This may allow adjustment of the coupling mechanism 75, e.g., to compensate for play and/or tolerances. A specific adjustment of the pivoting range of the material deflector 71 may also be enabled by such a thread.
(32) The deflection lever 77 may additionally be connected to an elastic element 81. The elastic element 81, in turn, can be connected to the material deflector 71 in such a way that a movement or deflection, for example an expansion or compression, of the elastic element 81 causes the material deflector 71 to move, in particular to pivot. The aforementioned components may interact in such a way that a movement of the lifting device 29 displaces the rod 79, whereby the deflection lever 77 can be rotated. The rotation of the deflection lever 77 can in turn move the elastic element 81, whereby the material deflector 71 can be moved, in particular pivoted.
(33) The elastic element 81 can be provided on a bar 82. This strut can be used to prevent the elastic element 81 from bending. The bar 82 may be telescopic to allow deflection of the elastic element 81. Similar to the rod 79, the bar 82 can have a thread through which the length of the bar 82 can be adjusted. This may provide an additional adjustment option for the coupling mechanism 75, e.g., to compensate for play and/or tolerances. A specific adjustment of the pivoting range of the material deflector 71 may also be enabled by such a thread. The coupling mechanism 75 may also have a bar 82 without an elastic element 81 being provided on it. In this case, any designs that are not telescopic are also conceivable. However, a thread may be advantageous in variants without elastic element 81 as well.
(34) FIG. 6A shows the lifting device 29 in a position, in which the chassis 3 is lifted in relation to the undercarriage 5. By the position of the rocker 31, the material deflector 71 was moved into a folded out position by the interaction of the rod 79, the deflection lever 77 and the elastic element 81. FIG. 6B shows the lifting device 29 in a position, in which the chassis 3 is disposed in a fully lowered position relative to the undercarriage 5. In this case, as can also be seen in FIG. 6B, the material deflector 71 is arranged in a folded position.
(35) In the schematic view shown in FIG. 7A, the chassis 3 and the undercarriages 5 can be seen from behind. Traction tracks 83 are defined by undercarriages 5. The material deflector 71 is arranged between the traction tracks 83. In FIG. 7A, the chassis is raised relative to the undercarriages 5 and the material deflector 71 is folded out. The lower edge 73 is arranged at a distance g from a ground 85. The distance h is defined between the chassis 3 and the ground 85.
(36) In FIG. 7B the chassis 3 is lowered relative to the undercarriage 5 by a lifting distance i relative to the position shown in FIG. 7A. The distance g between the lower edge 73 and the ground 85 is the same as in FIG. 7A.
(37) FIG. 8 is a schematic representation of the coupling mechanism 75 according to another embodiment. In this embodiment, the coupling mechanism 75 comprises a closed loop control unit 87. Alternatively, an open loop control unit may also be provided. Furthermore, the coupling mechanism 75 may have a sensor unit 89 according to this embodiment. This sensor unit may be configured to measure or determine the distance g between the lower edge 73 and the ground 85 and/or the lifting distance i and/or the distance h between the chassis 3 and the ground 85. The sensor unit 89 may be connected to the control unit 87 to transmit measured or detected values to the control unit 87.
(38) The coupling mechanism 75 according to the embodiment shown in FIG. 8 may also have an actuator unit 91. This actuator unit can be connected to control unit 87 to receive control signals. In cases where an open loop control unit is provided, the actuator unit 91 may also be connected to it to receive control signals. The actuator unit 91 may have an actuator 93. The latter may be configured to move the material deflector 71, in particular to pivot it. The actuator 93 may be any suitable actuator known to a person skilled in the art. In particular, electric, hydraulic, electrohydraulic or pneumatic actuators are conceivable, for example an electric or servo motor, or a hydraulic cylinder. Accordingly, the control unit 87 may be an electric, hydraulic, electrohydraulic or pneumatic control unit.
(39) Various possibilities are conceivable for closed loop or open loop controlling of the movement of the material deflector 71. For example, it is conceivable that the sensor unit 89 could detect the distance g between the lower edge 73 of the material deflector 71 and the ground 85 and transmit this to the control unit 87. The control unit 87 may then be configured to transmit control signals to the actuator unit 91 based on the received distance, said signals causing the actuator unit 91 to control the actuator 93 in such a way that the distance g between the lower edge 73 and the ground 85 remains constant.
(40) Alternatively, the sensor unit 89 can detect the lifting path i and transmit it to the control unit 87. Based on the lifting distance i, the latter may determine a target position of the material deflector 71, which is assigned to the detected lifting distance i. An assignment of a lifting path i to a position of the material deflector 71 may be made using mathematical formulas or tables. It is conceivable that the control unit 87 transmits the target position to the actuator unit 91 and that this actuator unit 91 independently controls the actuator 93 in such a way that the material deflector 71 assumes the received target position. However, it is also conceivable that the control unit 87 itself comprises a controller and only transmits control signals to the actuator unit 91.
(41) FIG. 9A shows a side view of an undercarriage 5 of a road finisher 1 according to another embodiment. In this embodiment, an undercarriage protector 95 is provided. The latter may be attached to the track carrier 37, for example, as shown in the embodiment. In the configuration shown in FIG. 9A, the chassis 3 is completely lowered relative to the undercarriage 5. In this configuration, the undercarriage protector 95 is covered to the rear by the chassis 3 when viewed in the driving direction. In this configuration, the chassis 3 prevents the paving material from entering the area of the undercarriage 5.
(42) In FIG. 9B, chassis 3 is lifted relative to the undercarriage 5. As in this embodiment, this may cause the undercarriage protector 95 to be exposed. In this configuration, the undercarriage protector 95 may prevent the paving material from entering the area of the undercarriage 5. It can also be seen that, without undercarriage protector 95, there would be considerably more space between the lower edge of chassis 3 and the ground, which would allow the paving material to enter the area of the undercarriage.
