EP2620549B1 - Paver with controllable conveyor devices - Google Patents

Description

The invention relates to a paver according to the preamble of claim 1 and to a method for operating a paver according to the preamble of claim 11.

It is known that a paver has a material handling system with which a built-in material required for road construction is conveyed from a bunker located in front in the direction of travel to the rear end of the paver in the direction of travel. For this purpose, such a paver has a longitudinal conveyor system, which is usually designed as a scraper belt. The longitudinal conveyor system conveys the mix against the direction of travel from front to back under the machine. The arranged at the rear end of the paver cross conveyor system, which is usually designed as a distributor screw, then serves the distribution of the mix in front of a screed and should ensure the most constant and uniform distribution of the mix in the transverse direction of the paver. Such a paver is for example from the DE 93 08 170 U1 known.

It is also known that the material throughput of the mixed material in the longitudinal conveyor system and in the transverse conveyor system depends on several parameters, for example the feed of the paver, the paving width, the installed thickness and the density of the mixed material. For this reason, for example, beat the US 3,678,817 the EP 0 279 795 A2 , the DE 20 2004 004 082 U1 and the DE 196 80 396 B4 Systems for controlling the longitudinal and / or transverse conveyor system to adjust the material throughput of the systems. These systems have in common that they have one or more sensors for detecting the current material throughput and regulate the conveying speeds or rates on the basis of this data.

A disadvantage of the proposed systems is that the interaction of a controller with the sensors for detecting the material throughput shows a certain, unavoidable latency, and so to a delay between the event - namely a detrimental change in the material throughput - and the reaction it comes on. For example, changes in the use of a pullout by pulling the same the pave width of the paver, so suddenly an increased Mischgutbedarf in the area of the screed arises. This is the sensor or the sensors only with a certain time delay, so that the associated control or regulation in response to it and with a further increased latency tries to compensate for the increased Mischgutbedarf by increasing the delivery rate of the longitudinal and / or the transverse conveyor system. In the process, sharp adjustments are first made so that the drives of the material delivery system suddenly accelerate. As a result, extreme load peaks can occur in the delivery units or components, so that the paver's diesel engine reaches the limits of its efficiency. This can cause a motor stop as a protective function and thus a mounting stop of the paver. Such a behavior causes a disadvantageous quality of the road to be manufactured and also has an adverse effect on the installation speed.

In the DE 10 2007 033 456 A1 a solution attempt for a similar problem is described. There is disclosed a pavement method and associated machine having a so-called feed forward feed control system. It is proposed that sensors be used to record measurements that indicate an increased need for material early, so that the conveyor system can be controlled in time so that no material shortage or excess occurs at the depository. In particular, the patch width and the paving thickness are mentioned as measured variables.

Object of the present invention is therefore to provide a paver with an improved conveyor system for the built-in material available, which increases the design quality of the paver with structurally simple means possible.

This object is achieved by a paver with the features of claim 1 and by a method having the features of claim 9. Advantageous developments of the invention are specified in the dependent claims.

The paver is characterized in that the control device for setting a delivery rate of the longitudinal and / or the transverse conveyor system in addition to the response to the sensor signal in response to detected installation parameters by means of a pilot control is vorsteuerbar. This results in a whole series of advantages. Due to the additional consideration of installation parameters in the control, it is possible to enable a constant operation of the paver even in the event of sudden deviating operating conditions. It is possible, in advance, ie before the changed operating conditions at a relevant point of the paver affect, to respond to them and adjust the material handling system accordingly. For example, it is theoretically possible to calculate the required delivery rate of the longitudinal conveyor and / or the cross conveyor from the installation parameters and to control the control device accordingly. This advantageously has the effect that the adjustment with the detection of the changed operating conditions by the sensor (s) takes place more smoothly, since, for example, the delivery rate of the delivery system increases already increased or decreased at that time. Thus, load peaks, which would result from the sharp Einregel, advantageously avoided.

In this case, a plurality of installation parameters can be detected simultaneously by the control device. For example, a calculation of the theoretically required delivery rate by the control device can take place as soon as the main vehicle switch of the paver is actuated. The road paver according to the invention thus offers the advantage that a largely constant speed of the conveyor system and thus a constant pre-compression of the built-in cargo is achieved by the feedforward control of the regulator device. This has a positive effect on the quality of the road created. In addition, the drive units of the paver are spared.

Among the installation parameters taken into account for feedforward control of the control device are user inputs and / or machine parameters of the road finisher. The advantage of this is that it allows the large number of observable parameters to achieve a particularly high-quality control or control of the conveyor system. In addition, the application effort for the system is reduced.

It has proved to be particularly advantageous if the control device and / or the feedforward control can be taught on the basis of the detected installation parameters; that is, the system is a self-learning system. This allows a self-learning determination of the pilot control values and improves the quality of the pilot control.

The installation parameters that can be taken into account by the control device can be any selection (ie one or more installation parameters) of installation width, steering position, position of an extension screed, installation thickness, paving speed, material supply, travel drive speed, road speed of the paver and bank inclination , For example, can be detected by the detection and evaluation of the drive speed of the right and left side of the paver cornering the paver. For example, a left turn requires an increased amount of built-in material on the right side of the paver, and vice versa. The feedforward control of the material conveyor system makes it possible to prevent a contraction caused by cornering, unsteady reaction of the conveyors in advance by the conveyors due to the detected cornering accordingly be pre-controlled. The large number of possible installation parameters effectively increases the control quality of the conveyor system.

Furthermore, the control device of the pilot control is overridden to increase the dependence of the delivery rate of the mounting parameters relative to the sensor. For example, if the sensors detect that there is currently too much built-in material in the area of the screed, the control device causes a reduction in the delivery rate of the longitudinal and / or transverse conveyor. However, if the driving speed of the paver is also increased or the paving width is increased, it is advantageous if these parameters are prioritized by the control device in order to avoid a hectic or sharp balancing. This has an advantageous effect on the quality of installation and also reduces load peaks in the drive units of the paver and the material handling system.

It is particularly advantageous if a theoretically required delivery rate of the longitudinal and / or transverse conveying device can be calculated and the regulating device can be pre-controlled as a function of this calculated delivery rate.

It has proven to be expedient if the ratio of the delivery rates of the longitudinal and transverse conveying device to one another is variably adjustable. As a result, the conveyor system of the paver can be adapted even more precisely to the operating conditions and thus the quality of installation can be improved.

It is particularly favorable if the delivery rate of the longitudinal and / or transverse conveying device can be set by speed-controlled drive units. If, for example, electrically adjustable, hydraulically operating drive units are used for the material delivery system, they can be adjusted in their rotational speed by simple control of the control current.

It is expedient if the sensor system comprises at least one non-contact level sensor. In principle, any contactless level or flow rate sensor is suitable for this purpose. Paddle, ultrasonic, and swing lever sensors have proven particularly useful.

Advantageously, the road paver according to the invention is a wheel paver or a tracked paver. Thus, the invention can be used in any of the most commonly used designs of road pavers.

The invention also relates to a method for operating a road paver. The method according to the invention is characterized in that the control device for the material delivery system can additionally be precontrolled by means of feedforward control as a function of installation parameters. The advantage of this is that thereby a feedforward control of the drive components of the material handling system of the paver can be made. This increases the quality of installation, avoids a sharp adjustment and thus reduces the load peaks occurring in the material handling system.

As installation parameters, user inputs and / or machine parameters of the paver are taken into account.

It may also be advantageous if the control device and / or the feedforward control is taught on the basis of the detected installation parameters. Thus, the material handling system is a self-learning system that simplifies the handling of the paver and can improve the quality of installation.

The installation parameters to be considered can be any number (ie one or more) of the pave width, the installation thickness, the installation speed, the longitudinal position, the position of a Ausziehbohle, the stock of material in the bunker, the traction drive speed, the speed of the entire paver and the bank of the screed to be selected. Thus, a wide selection of observable installation parameters is available, which allows a particularly efficient control of the conveyor system or the precontrol of the same.

It can also be advantageous if a theoretically required delivery rate of the longitudinal and / or transverse conveyor device is calculated from the installation parameters and the control device is precontrolled in accordance with this conveyor. Thus, the latency of the control or control is advantageously shortened.

Figur 1

eine stark schematische Prinzipdarstellung eines erfindungsgemäßen Straßenfertigers mit einer erfindungsgemäßen Vorsteuerung für eine Längsfördereinrichtung und eine Querfördereinrichtung eines Materialfördersystems und

Figur 2

eine schematische Darstellung des Funktionsprinzips einer erfindungsgemäßen Vorsteuerung für ein Materialfördersystem eines Straßenfertigers.

In the following, advantageous embodiments of the invention will be explained in more detail with reference to a drawing. In detail show:

FIG. 1

a highly schematic schematic diagram of a road finisher according to the invention with a feedforward control according to the invention for a longitudinal conveyor and a transverse conveyor of a material handling system and

FIG. 2

a schematic representation of the principle of operation of a feedforward control according to the invention for a material handling system of a paver.

Identical components are provided with the same reference numerals throughout the figures.

FIG. 1 shows a highly schematic representation of a road finisher 1 according to the invention with a feedforward control 2 according to the invention for a material handling system 3 of the paver 1. The paver 1 may be a wheeled paver or a paver.

The pilot control 2 is integrated, for example, in an electronic control unit with at least one arithmetic unit 2a, a data memory 2b and a switch 2c and further has a plurality of inputs 4 for detecting installation and / or machine parameters 4a, 4b, 4c, 4d and a Output 4e for outputting at least one calculable output signal 4f. To transmit the parameters 4a, 4b, 4c, 4d to the feedforward control 2, the paver 1 comprises a control panel 5. The parameters 4a, 4b and 4c are, for example, the installation width (EB width), the installation thickness (EB thickness) and the installation speed (EB speed).

The material conveyor system 3 shown comprises a longitudinal conveyor 6 for conveying a built-in cargo from the front part in the direction of travel to the rear of the paver 1. The longitudinal conveyor 6 is preferably a two-part scraper belt. Furthermore, the paver 1 comprises a cross conveyor 7, which is preferably a transverse distributor screw. In FIG. 1 in each case only one side of the longitudinal or transverse conveyor 6, 7 is shown, the other side is constructed analogously thereto.

To drive the longitudinal conveyor 6, the material conveyor system 3 shown has a hydraulic drive unit 8, which drives the longitudinal conveyor 6 with an adjustable speed. Next, the material conveyor system 3 has another Hydraulic drive unit 9 for driving the cross conveyor 7. The drive unit 9 drives for this purpose the transverse distributor screw with an adjustable speed.

To control a drive speed or a delivery rate of the material delivery system 3, the paver 1 has a in FIG. 1 The control device 10 can be summarized with the pilot control 2 to a common control unit, separately formed or integrated into any other control device of the paver 1. The control device 10 has in each case a first controller 11a, 11b and in each case a second controller 12a, 12b for controlling the hydraulic drive units 8, 9. The first controllers 11a, 11b are each configured to generate a control current for the hydraulic drive units 8, 9 , The second regulators 12a, 12b are each configured to cooperate with the precontrol 2, ie they are set up to interact with a precontrol signal of the precontrol 2 generated at the output 4e.

The road paver 1 furthermore has a sensor system which comprises at least one sensor 13a for monitoring the longitudinal conveyor device 6 and a further sensor 13b for monitoring the transverse conveyor device 7. Both sensors 13a, 13b may have the same embodiment, preferably as an ultrasonic, paddle or pivot lever sensor. All sensors 13a, 13b are configured for interaction with the control device 10 or connected thereto by means of electrical lines. It is also possible for each side of the longitudinal conveyor 6, i. for each individual scraper belt, and / or for each part of the cross conveyor 7, i. for each individual transverse distributor screw, to provide its own sensor. The sensors 13a, 13b are each configured to generate an electrical signal 13c, 13d, which represents the filling level of the installation material in a specific area of the material conveying system 3.

The operation of the road paver 1 described above can proceed as described below.

FIG. 2 schematically shows the operating principle of the feedforward control 2. In this embodiment, the feedforward control 2 determines a basic speed 14a for the longitudinal conveyor on the basis of several installation and machine parameters applied to the input 4 6 and / or the cross conveyor 7. The basic speed 14a is either by manual operation, ie by the manual input 4d of an operator on the control panel 5 of the paver 1, set, or it will be stored by the operator in the data memory 2b of the feedforward control 2 construction site data, so called PRESET data, called and set the base speed 14a accordingly. Another possibility is the consideration of the installation parameters 4a, 4b, 4c. For example, the basic rotational speed 14a can be controlled as a function of the manually altered installation width or cornering.

The feedforward control 2 combines the basic speed 14a with an automatic mode 15 to a drive speed 14b of the drive units 8, 9 of the longitudinal and / or transverse conveyors 6, 7 to be adjusted. The automatic mode 15 takes into account the signals 13c, 13d generated by the sensors 13a, 13b for this purpose current level of material delivery system 3.

Based on FIG. 1 will now be explained in the following, the interaction of the feedforward control 2 with the control device 10. The material delivery system 3 is a setpoint input 16 for a material height 16a of the longitudinal conveyor 6 and a further material height 16b of the cross conveyor 7 specified. The material heights 16a, 16b are represented within the material conveying system 3 by a respective setpoint voltage 16c, 16d. The signals 13c, 13d generated by the sensors 13a, 13b represent the current material height in the material conveying system 3 in the form of an electrical voltage, ie the actual voltage. The control device 10 now calculates from the voltage signals 13a, 13b and 16c, 16d a deviation 17a, 17b of the desired heights 16a, 16b from the material actual heights.

By the first controller 11a, 11b, respectively, the target voltage 16c, 16d adjusted to specify a control current 18a, 18b for the drive units 8, 9 of the material delivery system 3. By the switch 2c of the pilot control 2, the control currents 18a, 18b are switched on and the drive units 8, 9 are driven at the appropriate speed. Thereby, the value of the signals 13c, 13d representing the actual material height is influenced or changed.

The pilot control 2 according to the invention also allows the control currents 18a, 18b for the drive units 8, 9 to be recorded in the data memory 2b. From the recorded or stored control currents 18a, 18b, the feedforward control 2 can close by a calculation on the present installation situation and generate further solo control currents 19a, 19b. When these desired control currents 19a, 19b determined from the recorded control currents 18a, 18b are present, the pilot control 2 activates these values by means of the switch 2c instead of the desired control currents 18a, 18b. That is to say that either the control currents 18a, 18b of the first controllers 11a, 11b or the desired control currents 19a, 19b influenced by the second controllers 12a, 12b and the precontrol 2 are activated by the switch 2c, ie supplied to the drive units 8, 9 ,

• In einer Betriebsphase befindet sich der Schalter 2c in einer unteren Schalterstellung, um die ersten Regler 11 a, 11 b zu aktivieren. Gleichzeitig wird die Vorsteuerung 2 dazu konfiguriert, die von den ersten Reglern 11a, 11b bestimmten Steuerströme 18a, 18b für eine näher bestimmbare, z.B. durch den Bediener festlegbare oder in das System applizierbare, Zeitdauer in den Datenspeicher 2b aufzuzeichnen (Anlernen der Vorsteuerung 2). In dieser Betriebsphase der Vorsteuerung 2 erfolgt noch keine Vorsteuerung des Materialfördersystems 3. Dieses wird lediglich durch die Daten der Sensoren 13a, 13b und dem Regelverhalten der ersten Regler 11 a, 11 b beeinflusst.
• Befindet sich der Schalter 2c dagegen in einer oberen Schalterstellung, um die zweiten Regler 12a, 12b zu aktivieren, wird das Ausgangssignal 4f der Vorsteuerung 2 in dem für die Einbausituation berechneten Steuerstrom für die Antriebsaggregate 8, 9 berücksichtigt. Die zweiten Regler 12a, 12b sind dazu konfiguriert, das Signal 4f mit den Signalen 13c, 13d zu kombinieren. Diese Betriebsphase entspricht einem Vorsteuern des Materialfördersystems 3 durch die Vorsteuerung 2.
• In der oberen Stellung des Schalters 2c ist es ebenso möglich, die Gewichtung der Vorsteuerung 2 bzw. des von dieser erzeugten Signals 4f gegenüber dem zweiten Regler 12a, 12b zu erhöhen, um das Regelverhalten der zweiten Regler 12a, 12b durch die Vorsteuerung 2 zu übersteuern, oder die Gewichtung umgekehrt zu verringern.

Thus, the feedforward control 2 according to the invention allows FIG. 1 the following application possibilities or operating phases in the operation of the paver 1:

• In an operating phase, the switch 2c is in a lower switch position to activate the first controller 11 a, 11 b. At the same time, the feedforward control 2 is configured to record the control currents 18a, 18b determined by the first controllers 11a, 11b for a more definable period of time, for example determinable by the operator or applicable in the system, into the data memory 2b (teaching the precontrol 2). In this operating phase of the feedforward control 2, there is still no precontrol of the material conveying system 3. This is influenced only by the data of the sensors 13a, 13b and the control behavior of the first controllers 11a, 11b.
• On the other hand, if the switch 2c is in an upper switch position in order to activate the second regulators 12a, 12b, the output signal 4f of the pilot control 2 is taken into account in the control current for the drive units 8, 9 calculated for the installation situation. The second regulators 12a, 12b are configured to combine the signal 4f with the signals 13c, 13d. This operating phase corresponds to a pilot control of the material delivery system 3 by the feedforward control 2.
• In the upper position of the switch 2c, it is also possible to increase the weighting of the pilot control 2 or of the signal 4f generated by the latter relative to the second regulator 12a, 12b, in order to increase the control response of the second controller 12a, 12b to override by the feedforward control 2, or to reduce the weight inversely.

Based on the illustrated embodiment, the paver 1 according to the invention or the operation of the feedforward control 2 can be modified in many ways.

Optionally, only the installation and / or machine parameters applied to the inputs 4 of the pilot control 2 can be taken into account for determining the desired control currents 19a, 19b for the drive units 8, 9. It is also possible to consider the installation width, the installation thickness and the installation speed of the right and left travel drive of the paver 1 together or separately for the calculation of the desired control currents 19a, 19b. It is also conceivable that the steering angle of a road paver 1 is calculated.

Furthermore, it is possible for the feedforward control of the longitudinal conveying device 6 to additionally monitor the control flow 19b of the transverse conveying device 7 and to take it into account in the calculation of the desired control flow 19a. Thereby, the speed specification for the longitudinal conveyor 6 can be made simultaneously with the speed specification for the cross conveyor 7 and a material shortage in a range between longitudinal conveyor and cross conveyor 6, 7 can be prevented.

Furthermore, it is possible in the road paver according to the invention, for cost reasons, only one part of the material handling system, i. either the longitudinal conveyor 6 or the transverse conveyor 7, to regulate isolated and / or precede.

Claims (12)

1. Road finishing machine (1) with a controllable longitudinal conveyor device (6) and a controllable transverse conveyor device (7) for mixed laying material disposed behind it in the direction of motion, and with a control unit (10) for adjusting a delivery rate of the longitudinal conveyor device (6) and/or the transverse conveyor device (7), wherein the control unit (10) is connected to a sensory mechanism (13a, 13b) for determining a mixed laying material quantity or rate, the delivery rate is adjustable in response to a signal (13c, 13d) of the sensory mechanism (13a, 13b) representing the mixed laying material quantity or rate and the control unit (10) is additionally pilot controllable in response to laying parameters (4a, 4b, 4c, 4d) using a pilot control (2), characterized in that the laying parameters (4a, 4b, 4c, 4d) comprise user inputs and the control unit (10) is overridable by the pilot control (2) to increase the dependency of the delivery rate on the laying parameters (4a, 4b, 4c, 4d) compared to the sensory mechanism (13a, 13b).
2. Road finishing machine according to claim 1, characterized in that the control unit (10) and/or the pilot control (2) is trainable based on the laying parameters (4a, 4b, 4c, 4d).
3. Road finishing machine according to one of the preceding claims, characterized in that the laying parameters (4a, 4b, 4c, 4d) are a selection from the width of spread, the thickness of spread, the laying speed, the steering position, the position of an extendable screed, the material stock, the travel drive speed, the driving speed of the road finishing machine (1), and the lateral inclination of the screed.
4. Road finishing machine according to one of the preceding claims, characterized in that a theoretically required delivery rate of the longitudinal conveyor device (6) and/or the transverse conveyor device (7) is computable and the control unit (10) is pilot controllable in response to this delivery rate.
5. Road finishing machine according to one of the preceding claims, characterized in that the ratio of the delivery rates of the longitudinal conveyor device (6) and the transverse conveyor device (7) is variably adjustable with respect to each other.
6. Road finishing machine according to one of the preceding claims, characterized in that the delivery rate of the longitudinal conveyor device (6) and/or the transverse conveyor device (7) is adjustable by speed-controlled drive units (8, 9).
7. Road finishing machine according to one of the preceding claims, characterized in that the sensory mechanism (13a, 13b) comprises at least one level sensor.
8. Road finishing machine according to one of the preceding claims, characterized in that the road finishing machine (1) is a wheeled finisher or a track-laying drive finisher.
9. Method of operating a road finishing machine (1) with a controllable longitudinal conveyor device (6) and a controllable transverse conveyor device (7) for mixed laying material disposed behind it in the direction of motion, and with a control unit (10) for adjusting a delivery rate of the longitudinal conveyor device (6) and/or the transverse conveyor device, wherein the control unit (10) is connected with a sensory mechanism (13a, 13b) for determining a mixed laying material quantity, the delivery rate is adjusted in response to a signal (13c, 13d) of the sensory mechanism (13a, 13b) representing the mixed laying material quantity or rate and the control unit (10) is additionally pilot controlled in response to laying parameters (4a, 4b, 4c, 4d) using a pilot control (2), characterized in that user inputs are taken into consideration as laying parameters (4a, 4b, 4c, 4d) and that the control unit (10) can be overridden by the pilot control (2).
10. Method according to claim 9, characterized in that the control unit (10) and/or the pilot control (2) is trained based on the laying parameters (4a, 4b, 4c, 4d).
11. Method according to one of claims 9 or 10, characterized in that the laying parameters (4a, 4b, 4c, 4d) are selected from the width of spread, thickness of spread, laying speed, steering position, position of an extendable screed, material stock, travel drive speed, driving speed of the road finishing machine (1) and the angle of inclination of the road finishing machine (1).
12. Method according to one of claims 9 to 11, characterized in that from the laying parameters (4a, 4b, 4c, 4d), a theoretically required delivery rate of the longitudinal conveyor device (6) and/or the transverse conveyor device (7) is calculated and the control unit (10) is pilot controlled corresponding to this delivery rate.

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