Constant surface pattern during slipform paving

Abstract

A slipform paver includes a slipform mold having a mold width extending transverse to a paving direction. At least one leveling beam is supported behind the slipform mould for engaging an upper surface of the formed unhardened concrete structure to level the upper surface, the at least one leveling beam being configured to oscillate transversely to the paving direction. At least one forward speed sensor is configured to provide a forward speed signal corresponding to a forward speed of the slipform paver in the paving direction. The controller is configured to receive the forward speed signal and generate a command signal to control the lateral oscillation frequencies of the at least one leveling beam such that a constant relationship is maintained between the forward speed lateral oscillation frequencies.

Description

Technical Field

[0001] The present disclosure relates to a slipform paver and a method of controlling the same to provide a more consistent surface finish on a formed concrete structure. Background Art

[0002] During the slipform paving of concrete structures, a phenomenon encountered when using a levelling beam behind the slipform mould is that the vibrations of the levelling beam on the upper surface of the newly formed concrete structure will form patterns in the upper surface. The structure of these patterns depends on the forward speed of the paving machine and the vibration frequency of the levelling beam. In prior art paving machines, the vibration frequency of the transverse levelling beam and / or the longitudinal levelling beam is manually set and therefore the pattern formed on the upper surface will also change as the forward speed of the paving machine changes. These changing patterns lead to inconsistent surface treatment.

[0003] These and other problems are addressed by the present disclosure. Summary of the invention

[0004] In one embodiment, a slipform paver includes a machine frame and a plurality of ground engaging wheels or tracks supporting the machine frame from a ground surface. A slipform mold is supported from the machine frame for molding a mass of concrete (or concrete lumps) into a formed but unhardened concrete structure as the paver moves forward in a paving direction, the slipform mold having a mold width extending transverse to the paving direction. At least one leveling beam is supported behind the slipform mold for engaging an upper surface of the formed but unhardened concrete structure to level the upper surface, the at least one leveling beam being configured to vibrate transverse to the paving direction. At least one forward speed sensor is configured to provide a forward speed signal corresponding to a forward speed of the slipform paver in the paving direction. A controller is configured to receive the forward speed signal and generate a control signal to control a lateral vibration frequency of at least one leveling beam so as to maintain a constant relationship between the forward speed and the lateral vibration frequency.

[0005] The at least one flattening beam may comprise a transverse flattening beam having an elongated shape having a longest dimension extending transversely across at least a majority of the width of the mould.

[0006] In the above embodiments, the lateral vibration frequency sensor may be configured to provide a lateral vibration frequency signal corresponding to the lateral vibration frequency of the lateral leveling beam.

[0007] In the above embodiment, the slipform paving machine may further include a drive motor that rotatably drives an eccentric drive connected to the transverse leveling beam to generate transverse vibration of the transverse leveling beam, and the transverse vibration frequency sensor may be configured to detect a rotational speed of the drive motor.

[0008] In any of the above embodiments, the at least one screed beam may further include a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction.

[0009] In the above embodiment, the longitudinal leveling beam can vibrate parallel to the paving direction while vibrating transversely to the paving direction, and the controller can also be configured to generate a command signal to control the longitudinal vibration frequency of the longitudinal leveling beam so as to maintain a constant relationship between the forward speed and the longitudinal vibration frequency.

[0010] Any of the above embodiments may further include a transverse vibration frequency sensor and a longitudinal vibration frequency sensor, wherein the transverse vibration frequency sensor is configured to provide a transverse vibration frequency signal corresponding to the transverse vibration frequency of the longitudinal leveling beam, and the longitudinal vibration frequency sensor is configured to provide a longitudinal vibration frequency signal corresponding to the longitudinal vibration frequency of the longitudinal leveling beam. The controller may also be configured to receive the transverse vibration frequency signal and the longitudinal vibration frequency signal.

[0011] In the above embodiment, the slipform paving machine may further include at least one winch configured to pull the carriage carrying the longitudinal leveling beam left and right across the width of the mold, and the lateral vibration frequency sensor may be configured to detect the rotation speed of the at least one winch.

[0012] In any of the above two embodiments, the slipform paving machine may also include a drive motor that rotatably drives an eccentric drive connected to the longitudinal leveling beam to generate longitudinal vibration of the longitudinal leveling beam, and the longitudinal vibration frequency sensor may be configured to detect the rotation speed of the drive motor.

[0013] In any of the above embodiments, the slipform paving machine may further include a transverse oscillation frequency sensor configured to provide a transverse oscillation frequency signal corresponding to a transverse oscillation frequency of the at least one screed beam.

[0014] In any of the above embodiments, the mold width of the slipform mold may be an adjustable mold width.

[0015] In another embodiment, a method of operating a slipform paver including a slipform mold may include the following steps: (a) molding a mass of concrete with the slipform mold to form an unhardened concrete structure as the paver moves forward in a paving direction; (b) engaging an upper surface of the unhardened concrete structure with at least one screed beam supported behind the slipform mold and oscillating the at least one screed beam transversely to the paving direction to level the upper surface; (c) monitoring a forward speed of the slipform paver with a controller; and (d) automatically controlling a lateral oscillation frequency of the at least one screed beam with the controller to maintain a constant relationship between the forward speed and the lateral oscillation frequency, thereby forming a constant surface pattern on the upper surface of the unhardened concrete structure.

[0016] In the above method in step (b), the at least one levelling beam may comprise a transverse levelling beam having an elongated shape having a longest dimension extending transversely across at least a majority of the mould width of the slipform mould.

[0017] In the above method in step (b), the at least one screed beam may further include a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction, the longitudinal screed beam being located behind the transverse screed beam.

[0018] In the above method, step (b) may further include causing the longitudinal leveling beam to oscillate parallel to the paving direction, and at the same time causing the longitudinal leveling beam to oscillate transversely to the paving direction, and step (d) may further include automatically controlling the longitudinal oscillation frequency of the longitudinal leveling beam with a controller, so as to maintain a constant relationship between the forward speed and the longitudinal oscillation frequency.

[0019] In the above first method embodiment, in step (b), the at least one screed beam may comprise a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction.

[0020] In the above method, step (b) may further include causing the longitudinal leveling beam to oscillate parallel to the paving direction, and at the same time causing the longitudinal leveling beam to oscillate transversely to the paving direction, and step (d) may further include automatically controlling the longitudinal oscillation frequency of the longitudinal leveling beam with a controller, so as to maintain a constant relationship between the forward speed and the longitudinal oscillation frequency.

[0021] Numerous objects, features and advantages of the present invention will become readily apparent to those skilled in the art after reviewing the following description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is the left side elevation view of the slipform paver.

[0023] Figure 1A is along Figure 1 A schematic front elevation cross-sectional view taken along line 1A-1A of FIG. Figure 1 The front elevation of the slipform mould of a slipform paver.

[0024] Figure 2 yes Figure 1 Schematic left side elevation view of a slipform paver excluding the dowel rod inserter.

[0025] Figure 3 is a schematic rear elevation view of a transverse leveling beam.

[0026] Figure 4 is along Figure 3The line 4-4 is taken Figure 3 Left elevation section of the transverse leveling beam.

[0027] Figure 5 is a schematic left side elevation view of a portion of the longitudinal leveling beam and main frame of the paver.

[0028] Figure 6 It is along Figure 5 A front elevation view taken on line 6-6 of the drawings showing the longitudinal leveling beams of the car and the transverse beams on which the car travels.

[0029] Figure 7 is a schematic diagram of a control system of the paving machine, showing various sensor signal inputs and various output commands to various actuators of the paving machine.

[0030] Figure 8 Schematic diagram of the constant surface pattern formed by the transverse leveling beams.

[0031] Fig. 9 Schematic diagram of the constant surface pattern formed by the longitudinal leveling beam. DETAILED DESCRIPTION

[0032] The embodiments of the present disclosure described below are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed in the following detailed description. Instead, the embodiments are selected and described so that those skilled in the art can appreciate and understand the principles and practices of the present disclosure.

[0033] Referring now to the drawings and in particular to Figure 1 , a slipform paving machine is shown and generally designated by reference numeral 10. The machine 10 is configured to move in a paving direction 12 across a ground surface 14 for spreading, screeding and processing concrete into a formed but not yet hardened concrete structure 16 having an upper surface 18 generally exposed upwardly and terminating in side concrete sides such as 20.

[0034] The slipform paver 10 includes a main frame 22 and a slipform paver mold 24, which may also be referred to as a slipform mold 24 supported from the main frame 22. A left mold assembly 26 and a right mold assembly 28 are connected to the slipform paver mold 24 so that the slipform paver mold 24 is closed on the left and right sides to form lateral concrete sides such as 20 of the finished concrete structure 16.

[0035] like Figure 1A As best seen in FIG. 1 , the slipform mold 24 has a mold width 80 between the side form assemblies 26 and 28. The mold width 80 also corresponds to the width of the concrete structure 16 formed by the mold, which is expressed in Figure 3The slipform mold 24 may be an adjustable width slipform mold as is known in the art, but it will be appreciated that for any given paving operation the mold width 80 will be adjusted to the desired width and then will remain fixed during the paving operation.

[0036] The main frame 22 is supported from the ground surface by a plurality of ground engaging units such as 30, which in the illustrated embodiment are tracked ground engaging units 30. Wheeled ground engaging devices may also be used. Each ground engaging unit 30 is connected to the main frame 22 by a lifting column such as 32 attached to a swing arm such as 34. An operator station 36 is located on the main frame 22. As used herein, the terms "left" and "right" are from the point of view of an operator located at the operator station 36 and facing forward in the paving direction 12. A plough or spreader device 38 is supported from the main frame 22 in front of the slipform paver mold 24. A spreading auger 39 may be used instead of the plough 38. At the rear of the slipform paver mold 24, a dowel rod inserter device 40 may be provided.

[0037] At least one leveling beam 41 may be supported behind the slipform mold 24 for engaging the upper surface 20 of the formed but not yet hardened concrete structure to level the upper surface 20. The at least one leveling beam 41 is configured to oscillate transversely to the paving direction 12. The at least one leveling beam may include a transverse leveling beam 42 and / or a longitudinal leveling beam 44. The transverse leveling beam 42 is generally referred to as an "oscillating beam" 42 by those skilled in the art. The longitudinal leveling beam 44 is generally referred to as a "super leveler" 44 by those skilled in the art.

[0038] It will be appreciated that many slipform paving machines do not include a dowel rod inserter apparatus 40 . Figure 2 The further schematic diagram of shows the slipform paving machine 10 without the dowel rod inserter device 40. If the dowel rod inserter device 40 is not used, the transverse leveling beam 42 and / or the longitudinal leveling beam 44 may be arranged behind the slipform paving machine mold 24.

[0039] Furthermore, it should be appreciated that some slipform pavers do not include transverse leveling beams 42, and thus may include only longitudinal leveling beams 44. And some slipform pavers do not include longitudinal leveling beams 44, and thus may include only transverse leveling beams 42.

[0040] Figure 2 The slipform paving machine 10 is schematically shown including transverse screed beams 42 and longitudinal screed beams 44, but without the dowel rod inserter 40. It will be appreciated that the dowel rod inserter 40 may be placed between the slipform mold 24 and the transverse screed beams 42.

[0041] exist Figure 2In the figure, the lifting columns 32 are labeled 32F and 32R for the front and rear lifting columns, respectively. The tracks 30 are labeled 30F and 30R for the front and rear tracks, respectively. It will be understood that there are two front lifting columns 32F on the left and right sides of the machine 10, supporting the machine frame 22 from the two front tracks 30F. Similarly, there are two rear lifting columns 32R supporting the machine frame 22 from the two rear tracks 30R. Figure 1 and Figure 2 In both, the slipform paving machine 10 is shown as a four track machine having front and rear track ground engaging units 30 on each of the left and right sides of the machine.

[0042] It will be appreciated that the various features disclosed herein are equally applicable to a dual track paving machine, such as, for example, the Wirtgen model SP 62i, with one long track on each of the left and right sides of the machine frame, with one front lifting column and one rear lifting column on each side of the machine frame, supporting the machine frame from each of the two tracks. And it will be appreciated that the various features disclosed herein are equally applicable to a triple track paving machine, such as, for example, having a single track on one side of the machine and two tracks on the other side.

[0043] Each lifting column 32F, 32R is constructed as a retractable member and may include a hydraulic smart cylinder actuator, such as Figure 2 46F and 46R as seen in FIG. Extension and retraction of actuators 46F and / or 46R causes extension and retraction of lifting columns 32F and 32R and may raise or lower machine frame 22 relative to ground surface 14 and / or may adjust the longitudinal and / or lateral inclination of machine frame 22 relative to ground surface 14. Each hydraulic smart cylinder may include an integrated extension sensor to allow accurate monitoring and control of the extension of lifting columns 32. Alternatively, the lifting columns may include a conventional hydraulic cylinder and a separate associated extension sensor. Furthermore, optionally, the lifting columns may not have an extension sensor at all.

[0044] Figure 1 The plow or spreader device 38 identified in Figure 2 Schematically shown in FIG. 3 is a spiral spreader device 39 .

[0045] Behind the spiral spreader device 39 is a height-adjustable concrete supply gate 50. The gate 50 is supported from the machine frame 22 by one or more gate actuators 52 for adjusting the height of the gate 50 relative to the machine frame 22. The gate actuator 52 may also be configured as a hydraulic smart cylinder with an integrated extension sensor to allow accurate monitoring and control of the extension of the height of the gate 50. Alternatively, the gate actuator 52 may include a conventional hydraulic cylinder and may have a separate associated extension sensor. In addition, the gate actuator may not have an extension sensor at all.

[0046] Between the gate 50 and the slipform mold 24 are a plurality of vibrators 56 configured to be immersed in the concrete mass forming the slab or structure 16 to assist in compacting the concrete as the slipform mold 24 moves over the concrete mass.

[0047] During the paving process, a large amount of concrete material 16A is dumped onto the ground surface 14 in front of the paver 10. This is usually done by a series of dump trucks (not shown) dumping their loads of wet concrete onto the ground surface, so that the supply of concrete material 16A occurs in a series of continuous material dumps. Alternatively, the large amount of concrete can be provided by a side feeder, a shuttle, a placer-spreader or other known concrete supply device. The material 16A is spread transversely across the width of the paver 10 by a spreader device 38 or 39. The height of the concrete feed gate 50 is adjusted to control the amount of concrete material 16B directly in front of the slipform mold 24. With the help of the vibrator 56, the concrete material is consolidated and semi-liquidized, and the slipform mold 24 moves across the concrete material 16B to form it into a concrete slab 16. In the area 16C immediately behind the slipform mold 24, there may be some expansion in the height of the newly formed slab. A roll 16D of concrete material can be formed immediately in front of the transverse leveling beam 42.

[0048] A transverse levelling beam 42 is supported from the machine frame 22 behind the slipform mould 24 for engaging on the upper surface 18 of the formed, yet unhardened concrete structure 16 and oscillating transversely to the paving direction 12 to level the upper surface 18 . Figure 3 and Figure 4 One embodiment of the transverse flattening beam 42 is shown. The transverse flattening beam 42 includes a first transverse flattening beam member 58 and a second transverse flattening beam member 60 that are pivotally connected together at a pivot pin 62. The pivot actuator 64 allows the Figure 3 The two members 58 and 60 of the transverse leveling beam 42 are shown pivoted to conform to the crown (or protrusion) 66 in the upper surface 18 of the concrete structure 16. The outer end portion of the transverse leveling beam 42 is slidingly secured in the first adjustable vertical beam support 68 and the second adjustable vertical beam support 70.

[0049] The eccentric drive 72 is mounted on the first beam member 58 of the transverse leveling beam 42. A push rod 74 connects the eccentric drive 72 to the main frame 22. A drive motor 76 drives the eccentric drive 72 to swing the transverse leveling beam 42 left and right relative to the main frame 22 and the upper surface 18 of the concrete structure 16, as shown in FIG. Figure 3, to flatten the upper surface 18. A lateral oscillation frequency sensor 82 may be associated with the drive motor 76. The lateral oscillation frequency sensor 82 may be configured to provide a lateral oscillation frequency signal 82S (see Figure 7 In one embodiment, the lateral oscillation frequency sensor 82 may be configured to detect the rotational speed of the drive motor 76 .

[0050] The slipform mold 24 may be described as having a mold width 80, which will also be equal to the width 81 of the concrete structure 16 formed by the mold 24. Figure 3 As seen in Figure 3 It can also be seen that the transverse flattening beam 42, and in particular the first and second transverse beam members 58, 60, have an elongated shape with a longest dimension 78. The longest dimension 78 can be described as extending laterally across at least a majority of the mold width 80 and extending in a substantially parallel manner. Figure 3 In an embodiment, the longest dimension 78 is greater than the mold width 80 and the concrete structure width 81 .

[0051] The upper surface 18 may be further leveled by the action of a longitudinal leveling beam 44, which is a large self-leveling trowel that moves laterally left and right across the width of the slab 16 while reciprocating forward and backward. The structural details of one embodiment of such a longitudinal leveling beam 44 are described in Figure 5 and Figure 6 Shown in. Figure 5 is a schematic left side elevation view of the longitudinal screed beam 44 as supported by the main frame 22 of the paving machine 10. Figure 6 It is along Figure 5 Line 6-6 see Figure 5 8 and showing details of the car 88 and cross beam 102 described further below.

[0052] The longitudinal leveling beam 44 includes an elongated trowel 84 having a longest dimension 86 extending parallel to the paving direction 12. The trowel 84 is supported from a carriage 88 by a bracket 90 and a vertical leg 91. The vertical leg 91 is connected to the bracket 90 at a pivot connection 98. A drive motor 92 rotatably drives an eccentric drive 94, which is connected to the vertical leg 91 by a drive link 96. When rotated by the drive motor 92, the eccentric drive 94 causes the trowel 84 to oscillate longitudinally parallel to the advance direction 12.

[0053] The longitudinal oscillation frequency sensor 100 is associated with the drive motor 92 and is configured to provide a longitudinal oscillation frequency signal 100S corresponding to the longitudinal oscillation frequency of the trowel 84 of the longitudinal leveling beam 44 (see Figure 7 The longitudinal oscillation frequency sensor 100 may be configured to detect a rotation speed of the drive motor 92 .

[0054] The carriage 88 carrying the longitudinal leveling beam 44 is arranged to move transversely across the width 81 of the concrete structure 16 on a transverse beam 102, which in turn is supported by the main frame 22 of the paving machine 10. The carriage 88 includes upper wheels 104 and lower wheels 106, which ride on the transverse beam 102. At one or both ends of the transverse beam 102, a winch 108 may be attached to the carriage 102 by a cable 110. The carriage 88 and the longitudinal leveling beam 44 are moved left and right across the width 81 of the concrete structure 16 by the winch 108. Each winch 108 may be driven by a winch drive motor 112. It should be appreciated that the speed of movement of the longitudinal leveling beam 44 transversely across the width 81 of the concrete structure 16, and correspondingly the frequency of movement left and right across the width 81 (which may be referred to as the transverse oscillation frequency of the longitudinal leveling beam 44), is determined by the rotation speed of the winch 108. A transverse oscillation frequency sensor 114 may be associated with each winch drive motor 112 and configured to provide a transverse oscillation frequency signal 114S corresponding to the transverse oscillation frequency of the longitudinal screed beam 44 across the width 81 of the concrete structure 16 (see FIG. Figure 7 ). The transverse oscillation frequency sensor 114 can be configured to detect the rotational speed of its associated winch drive motor 112, and thereby the rotational speed of its associated winch 108. It should be appreciated that the transverse oscillation frequency sensor 114 can also be considered to detect the transverse speed of the carriage 88 and longitudinal screed beam 44 as they move across the width 81 of the concrete structure 16, but since the distance to be traveled during one left-right cycle is constant (2 times the width 81), the transverse speed will be proportional to the transverse oscillation frequency. The transverse oscillation frequency signal 114S therefore directly corresponds to the transverse oscillation frequency and transverse speed of the longitudinal screed beam 44.

[0055] Further details of the mechanical structure of suitable embodiments of transverse and longitudinal leveling beams 42, 44 may be found in US Pat. No. 6,471,442, assigned to the assignee of the present invention, the details of which are incorporated herein by reference. Control System

[0056] like Figure 7 As schematically shown in FIG. 1 , the machine 10 includes a control system 200 including a controller 202. The controller 202 may be part of the machine control system of the slipform paving machine 10, or it may be a separate control module. The controller 202 may be installed, for example, in a control panel located at the operator station 36. The controller 202 is configured to receive input signals from various sensors. The signals transmitted from the various sensors to the controller 202 are Figure 7 The diagram is schematically indicated in FIG. 2 by lines connecting the sensors to the controller, with arrows indicating the flow of signals from the sensors to the controller 202 .

[0057] For example, the controller 102 may receive a forward speed signal 116S from a forward speed sensor 116 corresponding to the forward speed of the paving machine 10 in the paving direction 12. The forward speed sensor 116 may be, for example, a rotary drive motor 118 (see FIG. 1 ) that drives one of the tracks 30 of the paving machine 10. Figure 7 ) associated with the forward speed sensor. Any other known forward speed sensor 116 may be used. For example, the forward speed sensor 116 may operate based on a global navigation satellite system (GNSS) signal received by a suitable position sensor carried by the paving machine 10. It should be appreciated that while there should be at least one forward speed sensor 116, there may be multiple forward speed sensors 116. For example, there may be one sensor 116 on the left track and one sensor 116 on the right track. Or each track may include a forward speed sensor 116, and the controller 202 may determine an average or minimum of the readings to ignore track slippage.

[0058] The controller 202 may receive the lateral oscillation frequency signal 82S from the lateral oscillation frequency sensor 82 associated with the drive motor 76 of the eccentric drive 72 of the lateral screed beam 42 .

[0059] The controller 202 may receive the transverse oscillation frequency signals 114S from two transverse oscillation frequency sensors 114 associated with the winch drive motors 112 of the one or more winches 108 driving the longitudinal screed beam 44 .

[0060] And the controller 202 may receive the longitudinal oscillation frequency signal 100S from the longitudinal oscillation frequency sensor 100 associated with the eccentric drive 94 of the longitudinal leveling beam 44 .

[0061] Similarly, the controller 202 will generate command signals for controlling the operation of the various drive motors described above. Figure 7 2 is schematically indicated by lines connecting the controller 202 to the various drive motors and related structure in the diagrammatic depiction, with arrows indicating the flow of command signals from the controller 202 to the respective drive motors. It will be appreciated that to control the hydraulic drive motors, the controller 202 may send electrical signals to electric / mechanical control valves (not shown) that control the flow of hydraulic fluid into and out of the drive motors.

[0062] The controller 202 includes or may be associated with a processor 204, a computer readable medium 206, a database 208, and an input / output module or control panel 210 having a display 212. An input / output device 214, such as a keyboard, joystick, or other user interface, is provided so that an operator can input instructions to the controller. It should be understood that the controller 202 described herein may be a single controller having all of the functions described, or it may include multiple controllers with the described functions distributed among the multiple controllers.

[0063] The various operations, steps or algorithms described in conjunction with controller 202 may be directly embodied in hardware, in a computer program product 216 such as a software module executed by processor 204, or in a combination of the two. Computer program product 216 may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk or any other form of computer readable medium 206 known in the art. Exemplary computer readable medium 206 may be coupled to processor 204 so that the processor can read information from and write information to the memory / storage medium. In an alternative, the medium may be integrated into the processor. The processor and the medium may reside in an application specific integrated circuit (ASIC). The ASIC may reside in a user terminal. In an alternative, the processor and the medium may reside in a user terminal as discrete components.

[0064] The term "processor" as used herein may refer to at least a general or special purpose processing device and / or logic as would be understood by one skilled in the art, including but not limited to a microprocessor, a microcontroller, a state machine, etc. A processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration.

[0065] In some embodiments, the data storage in the computer-readable medium 206 and / or the database 208 may include a database service, a cloud database, etc. In various embodiments, the computing network may include a cloud server, and in some embodiments may be part of a cloud application, where the various functions disclosed herein are essentially distributed between the computing network and other distributed computing devices. Any or all of the distributed computing devices may be implemented as at least one of an onboard controller, a server device, a desktop computer, a notebook computer, a smart phone, or any other electronic device capable of executing instructions. The processor of the device (such as a microprocessor) may be a general-purpose hardware processor, a dedicated hardware processor, or a combination thereof.

[0066] In particular, the controller 202 may be programmed to receive the forward speed signal 116S, the transverse oscillation frequency signal 82S of the transverse flattening beam 42, the transverse oscillation frequency signal 108S of the longitudinal flattening beam 44, and the longitudinal oscillation frequency signal 100S of the longitudinal flattening beam 44. And the controller 202 may be programmed to send a command signal 118C to control the forward speed via the drive motor 118, send a command signal 76C to control the transverse oscillation frequency of the transverse flattening beam 42 via the drive motor 76 of the eccentric drive motor 72, send a command signal 112C to control the transverse oscillation frequency of the longitudinal flattening beam 44 via one or more winch drive motors 112, and send a command signal 92C to control the longitudinal oscillation frequency of the longitudinal flattening beam 44 via the drive motor 92 of the eccentric drive 94. All command signals may be based at least in part on the forward speed signal and the corresponding oscillation frequency signal.

[0067] It will be appreciated that as the paver 10 advances in the paving direction 12, the oscillations of the transverse screed beams 42 and / or the longitudinal screed beams 44 on the upper surface 18 of the newly formed concrete structure 16 will form patterns in the upper surface 18. The structure of these patterns depends on the forward speed of the paver 10 and the frequency of oscillation of the transverse screed beams 42 and / or the longitudinal screed beams 44. In prior art pavers, the frequency of oscillation of the transverse screed beams 42 and / or the longitudinal screed beams 44 is manually set, and therefore as the forward speed of the paver changes, the pattern formed on the upper surface also changes. The present invention is directed to methods and apparatus for controlling the relationship between the forward speed and the frequency of oscillation of the transverse screed beams 42 and / or the longitudinal screed beams 44 so as to produce a constant pattern in the upper surface 18. This results in a more uniform finished surface, which is desirable for both aesthetic reasons and quality control reasons.

[0068] In particular, the controller 202 can be configured via the computer program product 216 to generate command signals to control the transverse oscillation frequency of either the transverse screed beam 42 or the longitudinal screed beam 44 so as to maintain a constant relationship between the advancement speed and the transverse oscillation frequency. As a result of this constant relationship, the associated screed beam 42 or 44 will form a constant surface pattern on the upper surface 18 of the concrete structure 16.

[0069] exist Figure 8 This constant relationship and the resulting constant surface pattern for the transverse leveling beam 42 is schematically illustrated in FIG. Figure 82, pattern 220 is schematically shown in the form of a sinusoidal structure having a wavelength L1 produced by transverse leveling beam 42. Transverse leveling beam 42 oscillates laterally to the left and right transverse to the direction of advance 12 (as indicated by double-headed arrow 222). Each point, such as 42a, on the bottom surface of transverse members 58, 60 of transverse leveling beam 42 will form a sinusoidal pattern on surface 18 whose wavelength L1 is the distance traveled by paving machine 10 during a single oscillation of eccentric drive 72. It should be appreciated that the actual pattern 220 will not be as shown. Figure 8 Rather than a single sinusoidal line as shown in , there will be a plurality of parallel sinusoidal surface textures that are generally in a sinusoidal pattern as shown.

[0070] For example, the transverse leveling beam may have a transverse oscillation frequency in the range of from about 0.5 to 2.0 cycles / second, with a transverse movement of several inches produced by the eccentric drive 72. Typical paving speeds suitable for the slipform paver 10 may range from 0 to 16 feet per minute (fpm) (0 to 490 centimeters per minute (cm / min)). For example, at a transverse oscillation frequency of 1.0 cycles / second, at a forward speed of 15 fpm (460 cm / min), the length L1 of the pattern 220 would be 3 inches (8 cm). The distance L1 is maintained constant by maintaining a constant relationship between the forward speed of the paver and the transverse oscillation frequency of the transverse leveling beam 42. If the forward speed decreases (or increases), the controller 202 will detect the change in forward speed and will reduce (or increase) the transverse oscillation frequency of the transverse leveling beam 42 by commanding the rotational speed of the drive motor 76 of the eccentric drive 72 to decrease (or increase) accordingly so as to maintain the distance L1 at a constant value.

[0071] The constant relationship and resulting constant surface pattern 224 for the longitudinal flattening beams 44 is Fig. 9 It is schematically shown in FIG. Fig. 9 The pattern 224 is Figure 8 The pattern is more complex because the longitudinal leveling beam 44 oscillates in both the transverse and longitudinal directions.

[0072] Fig. 9The pattern 224 includes a first sawtooth structure 226 having a wavelength L2. The wavelength L2 is the distance that the paver 10 travels in the paving direction 12 as the carriage 88 of the longitudinal leveling beam 44 moves from one edge of the concrete structure 16 to the other edge and back. The time for the carriage to move left and right once will depend on the speed of the winch 108 and the paving width 81 of the concrete structure. As previously described, the slipform paver 10 can have a paving mold 24 with an adjustable width, but for any given paving operation, the mold width 80 and the paving width 81 will be fixed. For example, a paver such as the Wirtgen SP94 can pave surfaces between 3.5 meters (11.5 feet) and 9.5 meters (31 feet) wide. For example, a typical speed of the carriage 88 may range from 0.5 to 2.0 feet per second (15 to 60 centimeters per second). Typical paving speeds suitable for the slipform paver 10 range from 0 to 16 feet per minute (fpm) (0 to 490 centimeters per minute (cm / min)). For example, at a carriage speed of 1 foot / second (30 cm / second) and a paving width of 15 feet (460 cm), it would take 30 seconds for the carriage to move from one edge of the paving to the other and back. The frequency is 2 cycles per minute. At a forward speed of 15 fpm (3 inches / second) (460 cm / minute (8 cm / second)), the L2 length of the pattern 224 would be 90 inches (7.5 feet) (230 cm). The distance L2 is kept constant by maintaining a constant relationship between the forward speed of the paver and the lateral oscillation frequency of the longitudinal screed beam 44. If the forward speed decreases (or increases), the controller 202 will detect the change in forward speed and will decrease (or increase) the lateral oscillation frequency of the longitudinal screed beam 44 by commanding a corresponding decrease (or increase) in the rotational speed of the drive motor 112 of the winch 108. This will keep the distance L2 at a constant value.

[0073] Each point on the bottom surface of the longitudinal flattening beam 44 will form a sawtooth pattern similar to 226 on the surface 18, with a wavelength L2. It should be appreciated that the actual pattern 226 will not be as Fig. 9 Rather than a single zigzag line shown in FIG, there will be a plurality of parallel zigzag surface textures generally presented in the zigzag pattern shown.

[0074] Fig. 9The pattern 224 includes a second sinusoidal structure 228 superimposed on a first zigzag structure 226 and has a wavelength L3. The wavelength L3 depends on the lateral travel speed of the carriage 88 and the longitudinal oscillation frequency of the eccentric drive 94 as detected by the longitudinal oscillation frequency sensor 100. Of course, as described above, the lateral travel speed of the carriage 88 is adjusted depending on the forward speed of the paver 10, so the wavelength L3 can also be described as depending on the forward speed of the paver 10 and the oscillation frequency of the eccentric drive 94. The longitudinal leveling beam 44 can have a longitudinal oscillation frequency in the range of from about 0.5 to 2.0 cycles / second, and its longitudinal movement caused by the eccentric drive 94 is several inches. For example, with a lateral carriage speed of 1 foot / second (30 cm / second) and a longitudinal oscillation frequency of 1.0 cycles / second, the distance L3 will be 1 foot (30 cm). For a paving width 81 of 15 feet (460 centimeters), a transverse carriage speed of 1 foot / second (30 centimeters / second) corresponds to a transverse oscillation frequency of the longitudinal screed beam 44 of 2 cycles per minute. The distance L3 is kept constant by maintaining a constant between the forward speed of the paver and the longitudinal oscillation frequency of the longitudinal screed beam 44. If the forward speed decreases (or increases), the controller 202 will detect the change in forward speed and will decrease (or increase) the longitudinal oscillation frequency of the longitudinal screed beam 44 by commanding a corresponding decrease (or increase) in the rotational speed of the drive motor 92 of the eccentric drive 94. This will keep the distance L3 at a constant value.

[0075] Each point on the bottom surface of the longitudinal flattening beam 44 will form a sinusoidal pattern similar to 228 having a wavelength L3 on the surface 18. It should be appreciated that the actual pattern 228 will not be as Fig. 9 Rather than a single sinusoidal line as shown in , there will be a plurality of parallel sinusoidal surface textures that are generally in a sinusoidal pattern as shown.

[0076] It should be appreciated that the paver 10 may be initially set up for a given paving operation using historically preferred parameters for the forward speed of the paver, the lateral speed of the carriage 88, and the oscillation frequency of the eccentric drives 72 and 94. With these initial settings, if the forward speed is held constant, a uniform pattern such as 220 and 224 will appear. However, in actual paving situations, it is not always possible to maintain a constant forward speed of the paver. Adjustment of the forward speed may be necessary for many reasons, such as changes in the characteristics of the feed concrete material provided at position 16A (see FIG. 14 ). Figure 2), changes in environmental conditions, etc. Using prior art pavers, any change in forward speed will result in a change in the resulting surface pattern produced by the transverse screed beams 42 and / or the longitudinal screed beams 44. However, using the system of the present invention, the controller 202 can monitor the forward speed via the forward speed sensor 116, and can generate command signals to control the oscillation frequency of the transverse screed beams 42 and / or the longitudinal screed beams 44 so that a constant relationship is maintained between the forward speed and the oscillation frequency of the transverse screed beams 42 and / or the longitudinal screed beams 44. For the longitudinal screed beam 44, this includes control of both the transverse oscillation frequency and the longitudinal oscillation frequency.

[0077] For example, a method of operating the slipform paving machine 10 may be described as comprising the following steps: (a) as the paver 10 moves forward in the paving direction 12, a mass of concrete 16A, 16B is molded with the slipform mold 24 to form an unhardened concrete structure 16; (b) engaging the upper surface 18 of the unhardened concrete structure 16 with at least one levelling beam 42, 44 supported behind the slipform mould 24 and oscillating the at least one levelling beam 42, 44 transversely to the paving direction 12 to level the upper surface 18; (c) monitoring the forward speed of the slipform paver using the controller 202; and (d) automatically controlling the transverse oscillation frequency of at least one screed beam 42 , 44 with the controller 202 so as to maintain a constant relationship between the advancement speed and the transverse oscillation frequency, thereby forming a constant surface pattern 220 , 224 on the upper surface 18 of the unhardened concrete structure 16 .

[0078] In the case where at least one leveling beam 41 further includes a longitudinal leveling beam 44, step (b) may include the longitudinal leveling beam 44 oscillating parallel to the paving direction 12, while the longitudinal leveling beam 44 oscillates transversely to the paving direction 12; and step (d) may include automatically controlling the longitudinal oscillation frequency of the longitudinal leveling beam using the controller 202 so as to maintain a constant relationship between the forward speed and the longitudinal oscillation frequency.

[0079] Thus, it can be seen that the apparatus and method of the present disclosure readily achieve the objects and advantages mentioned as well as those inherent therein. Although certain preferred embodiments of the present disclosure have been illustrated and described for purposes of the art, many changes may be made to the arrangement and construction of the parts and steps by those skilled in the art, which changes are encompassed within the scope and spirit of the present disclosure as defined by the appended claims. Each disclosed feature or embodiment may be combined with any other disclosed feature or embodiment.

Claims

1. A slipform paver, comprising: Machine frame: a plurality of ground engaging wheels or tracks for supporting the machine frame from a ground surface; a slipform mold supported from the machine frame for molding the mass of concrete into a shaped, unhardened concrete structure as the paving machine moves forward in a paving direction, the slipform mold having a mold width extending transverse to the paving direction; at least one leveling beam supported behind the slipform mold for engaging an upper surface of the formed, yet-to-harden concrete structure to level the upper surface, the at least one leveling beam being configured to oscillate transversely to a paving direction; at least one forward speed sensor configured to provide a forward speed signal corresponding to a forward speed of the slipform paving machine in the paving direction; as well as A controller is configured to receive the forward speed signal and generate a command signal to control the lateral oscillation frequency of at least one screed beam such that a constant relationship is maintained between the forward speed and the lateral oscillation frequency.

2. The machine according to claim 1, characterized in that: The at least one leveling beam includes a transverse leveling beam having an elongated shape with a longest dimension extending transversely across at least a majority of the width of the mold.

3. The machine according to claim 2, characterized in that Further including: A transverse oscillation frequency sensor is configured to provide a transverse oscillation frequency signal corresponding to the transverse oscillation frequency of the transverse leveling beam.

4. The machine according to claim 3, characterized in that Further including: a drive motor capable of rotationally driving an eccentric drive connected to the transverse screed beam to produce transverse oscillations of the transverse screed beam; as well as The lateral oscillation frequency sensor is configured to detect a rotation speed of the drive motor.

5. The machine according to claim 2, characterized in that: The at least one screed beam further comprises a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction.

6. The machine according to claim 5, characterized in that: The longitudinal leveling beam also oscillates parallel to the paving direction while oscillating transversely to the paving direction; and The controller is further configured to generate a command signal to control the longitudinal oscillation frequency of the longitudinal leveling beam such that a constant relationship is maintained between the advancement speed and the longitudinal oscillation frequency.

7. The machine according to claim 1, characterized in that: The at least one screed beam comprises a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction.

8. The machine according to claim 7, characterized in that: The longitudinal leveling beam also oscillates parallel to the paving direction while oscillating transversely to the paving direction; and The controller is further configured to generate a command signal to control the longitudinal oscillation frequency of the longitudinal leveling beam such that a constant relationship is maintained between the advancement speed and the longitudinal oscillation frequency.

9. The machine according to claim 8, characterized in that Further including: a transverse oscillation frequency sensor configured to provide a transverse oscillation frequency signal corresponding to the transverse oscillation frequency of the longitudinal leveling beam; a longitudinal oscillation frequency sensor configured to provide a longitudinal oscillation frequency signal corresponding to the longitudinal oscillation frequency of the longitudinal leveling beam; and The controller is further configured to receive the transverse oscillation frequency signal and the longitudinal oscillation frequency signal.

10. The machine according to claim 9, characterized in that Further including: at least one winch configured to pull the carriage carrying the longitudinal leveling beam side to side across the width of the mold; and Wherein the lateral oscillation frequency sensor is configured to detect a rotational speed of the at least one winch.

11. The machine according to claim 9, characterized in that Further including: a drive motor capable of rotationally driving an eccentric drive connected to the longitudinal flattening beam to produce longitudinal oscillations of the longitudinal flattening beam; as well as The longitudinal oscillation frequency sensor is configured to detect a rotation speed of the drive motor.

12. The machine according to claim 1, characterized in that Further including: A lateral oscillation frequency sensor is configured to provide a lateral oscillation frequency signal corresponding to the lateral oscillation frequency of the at least one screed beam.

13. The machine according to claim 1, characterized in that: The mold width of the sliding mold is an adjustable mold width.

14. A method of operating a slipform paving machine comprising a slipform mould, the method comprising: (a) as the paver moves forward in a paving direction, a mass of concrete is molded using a slipform mold to form a concrete structure that has not yet hardened; (b) engaging the upper surface of the unhardened concrete structure with at least one levelling beam supported behind the slipform mould and oscillating the at least one levelling beam transverse to the paving direction to level the upper surface; (c) monitoring the forward speed of the slipform paver using a controller; and (d) automatically controlling the transverse oscillation frequency of at least one screed beam with the controller so as to maintain a constant relationship between the advancement speed and the transverse oscillation frequency, thereby forming a constant surface pattern on the upper surface of the unhardened concrete structure.

15. The method according to claim 14, characterized in that: In step (b), the at least one levelling beam comprises a transverse levelling beam having an elongated shape with a longest dimension extending transversely to at least a majority of a mould width of the slipform mould.

16. The method according to claim 15, characterized in that: In step (b), the at least one screed beam further comprises a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction, the longitudinal screed beam being located behind the transverse screed beam.

17. The method according to claim 16, characterized in that: Step (b) further comprises oscillating the longitudinal screed beam parallel to the paving direction while oscillating the longitudinal screed beam transverse to the paving direction; and Step (d) also includes automatically controlling the longitudinal oscillation frequency of the longitudinal leveling beam with a controller so that a constant relationship is maintained between the advancement speed and the longitudinal oscillation frequency.

18. The method according to claim 14, characterized in that: In step (b), the at least one screed beam comprises a longitudinal screed beam having an elongated shape with its longest dimension extending parallel to the paving direction.

19. The method according to claim 18, characterized in that: Step (b) further comprises oscillating the longitudinal screed beam parallel to the paving direction and oscillating the longitudinal screed beam transverse to the paving direction; and Step (d) also includes automatically controlling the longitudinal oscillation frequency of the longitudinal leveling beam with a controller so that a constant relationship is maintained between the advancement speed and the longitudinal oscillation frequency.

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