EP3214222B1 - Screeds assembly and method of operating same - Google Patents

Description

The invention relates to a screed assembly for use on a paver according to the preamble of claim 1. Furthermore, the invention relates to a method for operating such a screed assembly.

Screed assemblies for road pavers are known in practice. They are used to smooth asphalt mix and compact. For this they are pulled by a tractor of a road finisher. In modern road pavers the screed assembly is usually pulled floating; This means that the screed rests on the mix to be smoothed and compacted and the buoyancy and consequently the thickness of the built-in paving are adjusted essentially by the angle of attack of the screed and the pulling speed.

It is known that one or more compacting devices are provided on screeds. Screed modules of the applicant, z. B. in the EP 2 514 872 A1 . EP 2 514 871 A1 and EP 2 366 931 A1 disclosed in different combinations, for example, tamper bars, vibration units and / or pressure bars.

Furthermore, screed assemblies are known which have a plurality of screed segments. It may, for example, as in the EP 2 514 871 A1 to act Ausziehsegmente of extending screeds, by extending the working width of the screed assembly can be increased. Likewise, rigid attachments are known.

At the beginning of an installation drive, a screed assembly is usually first deposited at a starting point. This may be an aid such. B. act a wooden beam on which the screed assembly is stored before the installation begins. Likewise, it may be a straight milled edge of an existing asphalt surface layer to which the newly built asphalt layer is to start.

It may happen that several compression units are arranged one behind the other in the direction of travel of the road paver and thus pass successively the transition between the tool or the just milled edge and the freshly laid asphalt mix. The reason for this may be, for example, that a plurality of compression devices are arranged one behind the other on one and the same screed segment, or else that screed segments, each with one or more compression devices, are arranged one behind the other. Conventional pavers activate all compaction equipment simultaneously. In the event that all compression devices too activated at the time at which the first compacting device passes through the transition, this will cause the compaction equipment that has not yet passed the transition to hit the tool or the already hardened preceding asphalt pavement and thereby damage the existing asphalt pavement or compaction equipment become. In cases where all compaction devices are only activated when all compaction equipment has passed the transition, initial sections of the newly installed lining remain unprocessed by the previous compaction equipment. According to the inventor, this can lead to inhomogeneities and consequently quality fluctuations or losses in the finished covering.

The object of the invention is to improve existing screed assemblies by structurally simple measures to the effect that a continuous quality of the asphalt covering is guaranteed, and to minimize the risk of damage or even destruction of machine components or already laid asphalt.

This object is achieved by a screed assembly with the features of claim 1 and by a method having the features of claim 10.

The screed assembly according to the invention for use on a paver comprises a control unit, a first compression device and a second compression device, which is arranged in a first direction behind the first compression device. The screed assembly according to the invention is characterized in that the control unit is configured to activate and / or deactivate the second compacting device relative to the first compacting device by a time period which is not equal to zero. Both in the first and in the second compression device may be z. B. to one or more tamper bars, vibration units and / or pressure bars act. The first direction may in particular be the direction of travel of the paver. The first and the second compression device can be provided on one and the same screed segment. It is also conceivable that the first compression device on a first screed segment, for. B. a base board, and the second compression device on a second screed segment, for. B. a pull-out or a cultivation and / or widening part is provided.

It is conceivable that the screed assembly comprises a first screed segment and a second screed segment, the second screed segment being in the first direction behind the first screed segment first screed segment is arranged, wherein the first screed segment comprises the first compression means and the second screed segment comprises the second compression means. The first and second screed segments, wherein each screed segment has at least one

Compressing device may also be on a run as is the case with a rigid screed.

However, embodiments are also conceivable in which two or more screed segments are arranged next to one another in the direction of travel. The screed segments can be arranged in alignment with each other. In such an embodiment, the screed segments can simultaneously pass the installation beginning or the installation end. In cases where the screed segments arranged in this way are provided with the same compression means, they may also be arranged in alignment with each other. It is then advantageous if a compression device of the first screed segment is activated simultaneously with the compression device (s) arranged in alignment with this compression device at the second and / or further screed segment (s). For two screed segments z. B. successively consecutive Verdichterseinrichtungspaare be activated. The screed segments may be provided in one or the same rigid (i.e., non-extendible) screed, distributed on a rigid base screed and attached rigid or extendable attachments, or distributed on an extendible scaffold and attached attachments.

It can be provided a sensor unit which is configured for the detection of an installation start and / or an installation end. This allows further automation of the activation or deactivation process of the compression devices. The sensor unit may include a plurality of sensors, each configured to detect an installation start and / or an installation end, and associated with a position of a compression device. A compression device can then be activated upon detection of the installation start by its associated sensor and deactivated upon detection of the installation end.

To simplify the construction of the sensor unit, only one sensor can be provided which detects the beginning of the installation or the end of the installation. The activation or deactivation of the individual compression devices can then take place after a period of time has elapsed, which is calculated as described below.

It is particularly advantageous if the sensor unit comprises a temperature sensor, a pyrometer, an infrared sensor, an ultrasonic sensor and / or a displacement sensor. The installation start or the installation end can be such. B. be detected by a temperature difference. It is conceivable z. B. the detection based on temperature differences between already laid and yet to be laid road surface, between two or more already laid Lining sections or layers or between already laid road surface and the supporting surface.

The invention may also relate to a paver. Such an inventive paver has a screed assembly of the type described above and a tractor configured to tow the screed assembly.

It is advantageous if the first direction corresponds to a direction of travel of the paver.

It is also conceivable that the control unit is configured to calculate the time period based on a road speed of the paver.

It is also conceivable that a defined in the direction of travel of the paver distance between the first and the second compression device is provided, and that the time corresponds to a time required for the paver to cover a distance whose length corresponds to the distance at a driving speed ,

The control unit may be provided, for example, on the tractor. This may be a central control unit of the paver, which is set up for the control of several functions and in addition to these functions can also take over the activation and / or deactivation of the compression devices according to the invention. It is also conceivable that the control unit is a separate control unit for controlling the functions according to the invention. This can be provided for example on the tractor, but also on the screed assembly.

The invention also relates to a method of operating a screed assembly for use on a paver. Such a method comprises the following steps: activating and / or deactivating a first compacting device of the screed assembly, activating and / or deactivating a second compacting device of the screed assembly, which is arranged behind the first compacting device in the direction of travel of the paver, after a predetermined period of time has elapsed Is zero. As already described above, both the first and the second compacting device may be tamper bars, vibration units and / or pressure bars. A screed segment may comprise any combination of such compaction equipment, eg, only one or more vibration units, tamper and vibration unit (s), tamper and 1 or 2 pressure bars or tamper, vibration unit (s) and 1 or 2 pressure bars.

It is advantageous if the time period is calculated based on a driving speed of the paver. This can, for. B. detected or determined by a sensor unit.

In addition, it is conceivable that the time period is calculated based on a distance defined between the compaction devices in the direction of travel of the road paver.

An installation start and / or installation end can also be detected by a sensor unit. As already mentioned, this allows a further automation of the activation or deactivation process of the compression devices. The sensor unit may include a plurality of sensors, each configured to detect an installation start and / or an installation end, and associated with a position of a compression device. A compression unit can then be activated upon detection of the installation start by its associated sensor and deactivated upon detection of the installation end.

To simplify the construction of the sensor unit, only one sensor can be provided which detects the beginning of the installation or the end of the installation. The activation or deactivation of the individual compression devices can then take place after a period of time which is calculated as described above. The sensor unit may comprise a temperature sensor, a pyrometer, an infrared sensor, an ultrasonic sensor or a displacement sensor.

It is also advantageous if an installation start and / or an installation end is detected by means of a temperature difference. It is conceivable z. B. the detection based on temperature differences between already laid and yet to be laid covering, between two or more already installed covering sections or layers or between already laid pavement and the supporting this underground.

In a further variant, the first compression device can be provided on a first screed segment of the screed assembly and the second compression device can be provided on a second screed segment of the screed assembly, which is arranged behind the first screed segment in the direction of travel of the road paver.

Fig. 1

zeigt einen Straßenfertiger mit einer Einbaubohlenbaugruppe gemäß der Erfindung.

Fig. 2

zeigt eine schematische seitliche Schnittansicht einer Einbaubohlenbaugruppe mit zwei Bohlensegmenten, die jeweils mehrere Verdichtungseinrichtungen aufweisen.

Fig. 3a und 3b

zeigen schematisch die Verbindungen zwischen einer Steuereinheit und Verdichtungseinrichtungen von zwei Bohlensegmenten, gemäß zwei unterschiedlichen Ausführungsformen.

Fig. 4

ist eine schematische Darstellung zweier Bohlensegmente in Draufsicht von oben zur Erläuterung von Abständen.

Fig. 5

ist eine schematische Darstellung zweier Bohlensegmente in einer Draufsicht von oben.

The invention relates to a screed assembly and a method of the type described above. Embodiments are explained in more detail below with reference to drawings.

Fig. 1

shows a paver with a screed assembly according to the invention.

Fig. 2

shows a schematic sectional side view of a screed assembly with two screed segments, each having a plurality of compression means.

Fig. 3a and 3b

schematically show the connections between a control unit and compression means of two screed segments, according to two different embodiments.

Fig. 4

is a schematic representation of two screed segments in plan view from above to explain distances.

Fig. 5

is a schematic representation of two screed segments in a plan view from above.

Fig. 1 shows a paver 1, which has a screed assembly 2 and a tractor 3. The tractor can be connected, for example by pulling arms 4 with the screed assembly 2. As a result, the screed assembly 2 can be pulled floating by the tractor 3 and thereby smooth and compact a layer of asphalt to be laid. In Fig. 1 In addition, a direction of travel F is shown, in which the road paver 1 moves.

In Fig. 2 It can be seen that the screed assembly 2 comprises a first screed segment 5 and a second screed segment 6. The second screed segment 6 is arranged in the direction of travel F behind the first screed segment 5, ie the first screed segment 5 always reaches an installation section to be machined in front of the second screed segment 6. The screed assembly 2 can be, for example, an extending screed. In the present embodiment, the first screed segment 5 is not extendible and the second screed segment 6 extendable. However, it is also conceivable that the first screed segment is extendable and the second screed segment 6 is not extendable. In a further variant, both screed segments 5, 6 can be extendable. The person skilled in the art is familiar with the fact that extendable screed segments 5, 6 are extendable in a lateral direction essentially perpendicular to the direction of travel of the road paver 1. Related to the Fig. 2 this would correspond to an extension perpendicular to the plane of the drawing. In the present exemplary embodiment, both the first screed segment 5 and the second screed segment 6 have a plurality of compacting devices 5a, 5b, 5c, 6a, 6b, 6c. The first screed segment 5 has a first tamper 5a, a first vibration unit 5b and a first set of pressing bars 5c. The second screed segment 6 has a second tamper 6a, a second vibration unit 6b and a second set of press bars 6c. Both the first set of pressing bars 5c and the second set of pressing bars 6c may have one or more pressing bars. It is also conceivable that the two screed segments 5 and 6 each have only one or more such compression devices 5a, 5b, 5c, 6a, 6b, 6c. Also, different configurations of the individual screed segments 5, 6 are conceivable.

In the present exemplary embodiment, all the mentioned compression devices 5a, 5b, 5c, 6a, 6b, 6c, apart from the pressing bar set 6c, can be regarded as the first compacting device in the sense of the invention. Analogously, all of the mentioned compression devices 5a, 5b, 5c, 6a, 6b, 6c can be regarded as a second compression device in the sense of the invention except for the tamper 5a. According to the invention, the screed segments 5, 6 and the compacting devices 5a, 5b, 5c, 6a, 6b, 6c successively pass an installation beginning 7. This can be defined for example by an edge 8, which is provided on an already laid asphalt layer 9. In cases where no already laid installation layer 9 is present, for example, a resource such. As a wooden beam, are used for placing the screed assembly 2. The installation beginning 7 is in Fig. 2 shown in different positions 7a, 7b, 7c, 7d relative to the screed assembly 2.

Before the start of the installation, the tractor 3 and consequently the screed assembly 2 is positioned so that in the direction of travel F furthest forward compression device 5a, 5b, 5c, 6a, 6b, 6c, arranged in the present embodiment, the tamper 5a, at the beginning of installation 7 , In Fig. 2 this corresponds to the positioning 7a. In this case, the screed assembly 2 can essentially rest on the already laid asphalt layer 9 or the auxiliary.

According to the present invention, an operator of the paver 1 can now with the start of the installation drive the activation of the compression devices 5a, 5b, 5c, 6a, 6b, 6c z. B. initialize by pressing a button. Thereafter, the tamper 5a is activated first. This can be z. B. immediately after initialization or when the tractor 3 is moving. After elapse of a predeterminable period of time T, the vibration unit 5b is activated without any further action on the part of the operator. In Fig. 2 this may correspond to the positioning 7b. Analogously, the further compression devices 5a, 5b, 5c, 6a, 6b, 6c are activated one after the other. The period of time T is chosen such that the respective compression device 5a, 5b, 5c, 6a, 6b, 6c is activated when the installation beginning 7 is exceeded.

If the screed segments 5, 6 are arranged next to one another and in alignment, the respective compression devices can also be arranged in alignment with one another (see FIG Fig. 5 ). The Compensating devices aligned with each other can then be activated simultaneously. ie, first, the compressors 5a and 6a are activated simultaneously, then the compressors 5b and 6b, and finally the compressors 5c and 6c. Escaping compression devices can z. B. be provided in the following configurations: It is conceivable that both screed segments 5, 6 are provided in one and the same base board. It is also conceivable that one of the screed segments 5, 6 is provided on a rigid base screed and the other on a mounted on this base screed rigid or extendable broadening and / or attachment. In addition, one of the screed segments 5, 6 may be provided on an extendable base screed and the other on a broadening and / or attachment attached thereto.

In a further variant, it is conceivable that, for example, to simplify a control circuit, the compression devices 5a, 5b, 5c, 6a, 6b, 6c of a respective screed segment 5, 6 can only be activated together. In this case, the compression means 5a, 5b, 5c of the first screed segment 5 are activated at the beginning of the installation drive. This can be done, for example, if the positioning 7c according to Fig. 2 is present. After elapse of a time period T1, the compression means 6a, 6b, 6c of the second screed segment 6 are activated. The period T1 is selected in this case so that the compression means 6a, 6b, 6c of the second screed segment 6 are activated when passing through the installation beginning 7, for example, if positioning 7d according to Fig. 2 is present.

In this way, suitable time periods T can be provided between the activation times of any number of different compression devices 5a, 5b, 5c, 6a, 6b, 6c arranged one behind the other in the direction of travel F. It can thereby be ensured that the individual compression devices 5a, 5b, 5c, 6a, 6b, 6c are activated in each case when passing through the installation beginning 7. An analogous procedure can be provided for the deactivation at an installation end.

The time span T between the activation times of two compression devices 5a, 5b, 5c, 6a, 6b, 6c can be based on a travel speed of the paver 1 in the direction of travel F and / or at a distance D (see FIG Fig. 4 ) between the respective compression devices 5a, 5b, 5c, 6a, 6b, 6c. In embodiments in which the compaction devices 5a, 5b, 5c, 6a, 6b, 6c are activated grouped according to screed segments 5, 6, the distance D can also be defined between the screed segments 5, 6.

In the Fig. 3a and 3b the connection between different components of the road paver 1 and in particular the screed assembly 2 is shown schematically. A control unit 10 can be seen. This can be provided on the road paver 1 or on the screed assembly 2. It is connected to input devices 12 via first control lines 11. In the input devices 12 may be z. Example, to a sensor unit 12a or an operating device 12b act.

The sensor unit 12a can be set up, for example, to detect the travel speed of the road paver 1 or to determine it from other parameters which can be detected by it. It is also conceivable that the sensor unit 12a is configured to detect the installation start 7 and / or an installation end, for. B. by detecting the edge 8. This could, for. B. by the paver already existing height sensors, as they are for. B. used for leveling done. The sensor unit 12a may also be configured to detect if and / or when the tractor 3 or paver 1 is moving. Also several sensor units 12a, which are set up for different purposes, are conceivable.

The sensor unit 12a or the sensor units 12a can also be z. B. include one or more temperature sensors, pyrometers, infrared sensors, ultrasonic sensors and / or displacement sensors. The installation start 7 or the installation end can then be detected for example by an infrared sensor or a pyrometer based on a temperature difference between already laid and yet to be laid covering. The sensor unit 12a may include one or more sensors 16.

For example, sensors 16a, 16b and 16c may be provided and configured to recognize the installation beginning 7 and the installation end, respectively. Each of the sensors 16a, 16b and 16c may be associated with the position of one or more of the compression devices 5a, 5b, 5c, 6a, 6b, 6c. If one of the sensors 16a, 16b, 16c detects the start of installation 7, the compression device (s) 5a, 5b, 5c, 6a, 6b, 6c assigned to it can be activated. Upon detection of the installation end, its associated compactor (s) 5a, 5b, 5c, 6a, 6b, 6c may be disabled accordingly.

The operating device 12b may be configured to accept user information from an operator of the road finisher 1 or the screed assembly 2. Similar to the control unit 10, it may be provided on both the tractor 3 and the screed assembly 2. It is also conceivable that the operating device 12b and the control unit 10 are arranged in one and the same housing. However, an arrangement in different housings is also conceivable.

The control unit 10 may be a control device 10 specifically provided for controlling the compression devices 5a, 5b, 5c, 6a, 6b, 6c. However, it is also possible that the control device 10 is also provided for controlling further functions of the road paver 1.

By broken lines, the first screed segment 5 and the second screed segment 6 are indicated. The screed segment 5 comprises a tamper drive unit 13a, a vibration drive unit 13b and a pressure bar drive unit 13c. The tamper drive unit 13a may comprise, for example, an eccentric shaft which may be driven, for example, by a hydraulic motor or an electric motor. The vibration drive unit 13b may include, for example, an imbalance shaft, the z. B. can be driven by a hydraulic motor or an electric motor. The pressure bar drive unit 13c can comprise, for example, a pulse-hydraulic drive. A drive by means of electrical actuators is conceivable. The control unit 10 is connected via second control lines 14 to the drive units 13 of the first screed segment 5. The second screed segment 6 has in the present embodiment, analogous to the first screed segment 5, a tamper drive unit 15a, a vibration drive unit 15b and a pressure bar drive unit 15c. These can be configured analogously to the drive units 13 of the first screed segment 5 and connected to the control unit 10.

In the present exemplary embodiment, two screed segments 5, 6 are provided which each have three different compression devices 5a, 5b, 5c, 6a, 6b, 6c and the associated drive units 13, 15. However, screed assemblies 2 with any number of screed segments are conceivable, for. B. only one screed segment or more than two screed segments. Likewise, a single screed segment or a plurality of screed segments may each have any desired different combinations of compacting devices 5a, 5b, 5c, 6a, 6b, 6c.

The control unit 10 may be an electrical control unit, a hydraulic control unit or an electrohydraulic control unit. Accordingly, the control lines 11, 14 may be configured, ie they may be electrical as well as hydraulic control lines. In particular, the control lines 11 may be electrical lines. The control lines 14 may depend on the type of drive unit connected to it be configured. A control line 14, which is connected to a hydraulic drive unit 13, 15, can therefore be a hydraulic control line 14.

The control lines 14 may, as in Fig. 3a shown to be branched control lines. These may be connected at a central connection point, for example an output of the control unit 10, and then branch correspondingly to the drive units 13, 15. According to Fig. 3b However, a separate control line 14 can also be provided for each drive unit 13, 15. In addition, it is conceivable that a branched control line 14 is provided for a first group of drive units, which connects a plurality of drive units from this same group to a terminal of the control unit 10, and a second group of drive units in each case by a separate control line 14 to the control unit 10th connected is.

The time periods T, T1 may be determined based on a distance D between the respective compression devices 5a, 5b, 5c, 6a, 6b, 6c and plank segments 5, 6, respectively. The distance D may be defined in the direction of travel F. It may be defined in pairs between individual compaction devices 5a, 5b, 5c, 6a, 6b, 6c or slab segments 5, 6, or respectively with respect to the foremost compression device 5a or with respect to the foremost screed segment 5. In addition, it may be defined in each case between front ends of the respective compression directions 5a, 5b, 5c, 6a, 6b, 6c or plank segments 5, 6, as in FIG Fig. 4 shown on the right, or between rear ends of the compression means 5a, 5b, 5c, 6a, 6b, 6c and screed segments 5, 6, as in Fig. 4 shown on the left. The same applies to distances D between screed segments 5, 6.

Claims (15)

1. Screed assembly (2) for use at a road finisher (1), wherein the screed assembly (2) comprises:

   a control unit (10),

   a first compacting device (5a, 5b, 5c, 6a, 6b), and

   a second compacting device (5b, 5c, 6a, 6b, 6c), which is arranged in a first direction (F) behind the first compacting device (5a, 5b, 5c, 6a, 6b), characterized in that the control unit (10) is configured to activate and/or deactivate the second compacting device (5b, 5c, 6a, 6b, 6c) in a delayed manner relative to the first compacting device (5a, 5b, 5c, 6a, 6b) by a time period (T, T1), which is unequal to zero.
2. Screed assembly according to claim 1, characterized in that the screed assembly (2) comprises a first screed segment (5) and a second screed segment (6), wherein the second screed segment (6) is arranged in the first direction (F) behind the first screed segment (5), and wherein the first screed segment (5) comprises the first compacting device (5a, 5b, 6c) and the second screed segment (6) comprises the second compacting device (6a, 6b, 6c).
3. Screed assembly according to one of the preceding claims, characterized in that a sensor unit (12a) is provided, which is configured to detect an installation start (7) and/or an installation end.
4. Screed assembly according to claim 3, characterized in that the sensor unit (12a) comprises a temperature sensor, a pyrometer, an infrared sensor, an ultrasonic sensor and/or a path sensor.
5. Road finisher (1) characterized by a screed assembly (2) according to one of the preceding claims and a tractor (3), which is configured to tow the screed assembly (2).
6. Road finisher according to claim 5, characterized in that the first direction (F) corresponds to a direction of travel (F) of the road finisher (1).
7. Road finisher according to claim 5 or 6, characterized in that the control unit (10) is configured to calculate the time period (T, T1) based on a driving speed of the road finisher (1).
8. Road finisher according to one of the claims 5-7, characterized in that a distance (D) defined in the direction of travel (F) of the road finisher (1) is provided between the first and the second compacting device (5a, 5b, 5c, 6a, 6b, 6c), and that the time period (T, T1) corresponds to a time required by the road finisher (1) to cover a distance, the length of which corresponds to said distance (D), with a driving speed.
9. Road finisher according to one of the claims 5-8, characterized in that the control unit (10) is provided at the tractor (3).
10. Method for operating a screed assembly (2) for use at a road finisher (1), comprising:

    activating and/or deactivating a first compacting device (5a, 5b, 5c, 6a, 6b) of the screed assembly (2),

    characterized by activating and/or deactivating a second compacting device (5b, 5c, 6a, 6b, 6c) of the screed assembly (2), which is arranged in the direction of travel (F) of the road finisher (1) behind the first compacting device (5a, 5b, 5c, 6a, 6b), after expiration of a predeterminable time period (T, T1), which is unequal to zero.
11. Method according to claim 10, characterized in that the time period is calculated based on a driving speed of the road finisher (1).
12. Method according to claim 10 or 11, characterized in that the time period (T, T1) is calculated based on a distance (D) defined in the direction of travel (F) of the road finisher (1) between the compacting devices (5a, 5b, 5c, 6a, 6b, 6c).
13. Method according to one of the claims 10-12, characterized in that an installation start (7) and/or an installation end are detected by a sensor unit (12a).
14. Method according to one of the claims 10-13, characterized in that an installation start (7) and/or an installation end are detected by means of a temperature difference.
15. Method according to one of the claims 10-14, characterized in that the first compacting device (5a, 5b, 5c) is provided at a first screed segment (5) of the screed assembly (2) and that the second compacting device (6a, 6b, 6c) is provided at a second screed segment (6) of the screed assembly (2), which is arranged in the direction of travel of the road finisher (1) behind the first screed segment (5).

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