CN113924395A

CN113924395A - Asphalt rolling and leveling machine

Info

Publication number: CN113924395A
Application number: CN202080021371.1A
Authority: CN
Inventors: 渡边哲也; 高山英纪
Original assignee: Sumitomo SHI Construction Machinery Co Ltd
Current assignee: Sumitomo SHI Construction Machinery Co Ltd
Priority date: 2019-03-29
Filing date: 2020-03-24
Publication date: 2022-01-11
Also published as: EP3951061A4; JPWO2020203475A1; EP3951061A1; WO2020203475A1; JP7410931B2

Abstract

An asphalt finisher (100) is provided with an information acquisition device (51) for acquiring information on the surface of a paving material compacted by a finisher (3), and a controller (50). The leveling machine (3) includes a front side leveling machine (30) and a rear side leveling machine (31) which are arranged in a staggered manner in the vehicle length direction. The controller (50) determines whether there is a difference in elevation (LD) formed between the surface of the paving material compacted by the front-side screed (30) and the surface of the paving material compacted by the rear-side screed (31) based on the information acquired by the information acquisition device (51).

Description

Asphalt rolling and leveling machine

Technical Field

The invention relates to an asphalt rolling machine.

Background

Conventionally, an asphalt finisher including a rear side finisher which is extendable and retractable in the right and left direction with respect to a front side finisher is known (see patent document 1). The asphalt finisher expands the width of the paved road by extending the rear side finisher.

Prior art documents

Patent document

Patent document 1: japanese patent laid-open publication No. 2017-160636

Disclosure of Invention

Technical problem to be solved by the invention

However, the above asphalt finisher is configured such that the surface of the paving material compacted by the front side finisher (hereinafter, referred to as "central paving surface") and the surface of the paving material compacted by the rear side finisher (hereinafter, referred to as "side paving surface") are locally repeated in the traveling direction.

Therefore, the asphalt finisher described above causes a difference in height between the center paved surface and the side paved surfaces, and as a result, a difference in height occurs between the surfaces of the finally produced paved body, i.e., the paved surfaces, and the quality of the paved surfaces may be deteriorated.

Accordingly, it is desirable to provide an asphalt finisher capable of suppressing a decrease in quality of a paved surface.

Means for solving the technical problem

An asphalt finisher according to an embodiment of the present invention includes: a tractor; a hopper provided at a front side of the tractor and accommodating paving material; a conveyor belt that feeds paving material in the hopper to a rear side of the tractor; a screw spreading paving material supplied by the conveyor belt at a rear side of the tractor; a leveler that compacts the paving material spread by the screw at a rear side of the screw; an information acquisition device that acquires information relating to a surface of paving material compacted by the screed; and a control device including a front side leveling machine and a rear side leveling machine arranged to be staggered in a vehicle length direction, the control device determining whether there is a difference in level formed between a surface of the paving material compacted by the front side leveling machine and a surface of the paving material compacted by the rear side leveling machine, based on the information acquired by the information acquisition device.

Effects of the invention

According to the above aspect, an asphalt finisher capable of suppressing a decrease in quality of a paved surface is provided.

Drawings

Fig. 1 is a side view of an asphalt finisher according to an embodiment of the present invention.

Fig. 2 is a top view of the asphalt finisher of fig. 1.

Fig. 3 is a block diagram showing a configuration example of the lifting system of the leveler.

Fig. 4 is a cross-sectional view of the pavement.

Fig. 5A is a diagram showing an example of display of a screen displayed on the display device.

Fig. 5B is a diagram showing an example of display of a screen displayed on the display device.

Fig. 5C is a diagram showing an example of display of a screen displayed on the display device.

Fig. 6 is a flowchart of the height adjustment process.

Fig. 7A is a side view of the screed and the paving body.

Fig. 7B is a side view of the screed and the paving body.

Fig. 7C is a side view of the screed and the paving body.

Fig. 7D is a side view of the screed and the paving body.

Detailed Description

Fig. 1 is a side view of an asphalt finisher 100 as an example of road machinery according to an embodiment of the present invention. Fig. 2 is a top view of asphalt finisher 100. The asphalt finisher 100 is mainly composed of a tractor 1, a hopper 2, a finisher 3, and the like. Hereinafter, the direction (+ X direction) of the hopper 2 as viewed from the tractor 1 is referred to as the front, and the direction (-X direction) of the leveler 3 as viewed from the tractor 1 is referred to as the rear.

The tractor 1 is a mechanism for running the asphalt finisher 100. In the present embodiment, the tractor 1 rotates the rear wheel 5 using the rear wheel traveling hydraulic motor, and rotates the front wheel 6 using the front wheel traveling hydraulic motor to move the asphalt finisher 100. The rear wheel traveling hydraulic motor and the front wheel traveling hydraulic motor receive the supply of hydraulic oil from the hydraulic pump and rotate. The rear wheels 5 and the front wheels 6 may be replaced with crawler belts.

The controller 50 is a control device that controls the asphalt finisher 100. In the present embodiment, the controller 50 is configured by a microcomputer including a CPU, a memory, a nonvolatile storage device, and the like, and is mounted on the traction machine 1. The functional elements of the controller 50 that perform the respective functions are realized by the CPU executing a program stored in the nonvolatile storage device. However, each functional element in the controller 50 may be configured by hardware, firmware, or the like.

The hopper 2 is a mechanism for containing paving material. In the present embodiment, the hopper 2 is provided on the front side of the tractor 1 and is configured to be openable and closable in the Y-axis direction (vehicle width direction) by a hopper cylinder. Typically, the asphalt finisher 100 has the hopper 2 in a fully open position to receive paving material from the cargo box of the dump truck. The paving material is, for example, a bituminous mixture. Fig. 1 and 2 show the hopper 2 in a fully open state. Typically, an operator of asphalt finisher 100 closes hopper 2 if the paving material in hopper 2 decreases, and concentrates the paving material present near the inner wall of hopper 2 in the central portion of hopper 2. This is to enable paving material to be supplied to the rear side of the tractor 1 via the conveyor belt CV present in the central portion of the hopper 2. The paving material supplied to the rear side of the tractor 1 is spread in the vehicle width direction by the screw SC on the rear side of the tractor 1 and the front side of the leveler 3. In the present embodiment, the screw SC is in a state in which the extension screws are coupled to the left and right. In fig. 1 and 2, the paving material PV spread by the screws SC is shown in a thick pearskin pattern.

The screed 3 is a mechanism for compacting the paving material PV. In the present embodiment, the screed 3 includes a front side screed 30 and a rear side screed 31. Also, the front side screed 30 includes a left front side screed 30L and a right front side screed 30R, and the rear side screed 31 includes a left rear side screed 31L and a right rear side screed 31R.

The leveler 3 is a floating leveler dragged by the tractor 1, and is coupled to the tractor 1 via a leveling arm 3A. The leveling machine 3 moves up and down together with the leveling arm 3A by the extension and retraction of the leveling machine jacking cylinder 25.

The leveling cylinder 28 is a hydraulic cylinder that moves the front end portion of the leveling arm 3A up and down in order to adjust the leveling thickness of the paving material. In the present embodiment, the leveling cylinder 28 includes a left leveling cylinder 28L and a right leveling cylinder 28R.

In the present embodiment, the rear side leveling machine 31 is configured to be extendable and retractable in the vehicle width direction by an extension and retraction cylinder, not shown. However, the rear side leveler 31 may be a fixed (non-telescopic) leveler that is connected when in use using a crane or the like.

A screed lifter 29 is installed at a coupling portion of the front side screed 30 and the rear side screed 31. The screed elevating device 29 is configured to move the rear side screed 31 up and down with respect to the front side screed 30. In the present embodiment, the screed elevating device 29 rotates a screed elevating motor as a hydraulic actuator in accordance with a control command from the controller 50, and drives a rotation/linear motion converting mechanism attached to the rear side screed 31 to move the rear side screed 31 up and down. The leveler elevator 29 includes a left leveler elevator 29L that moves the left rear leveler 31L up and down and a right leveler elevator 29R that moves the right rear leveler 31R up and down. The rotation/linear motion conversion mechanism is, for example, a bolt/nut mechanism. The rotation/linear motion conversion mechanism may be a ball screw mechanism, a rack and pinion mechanism, or other mechanisms. The motor for lifting the screed may be an electric motor. The screed lifting device 29 may also be a hydraulic cylinder.

A mold plate 43 is mounted on the front of the leveler 3. The mold plate 43 includes a left mold plate 43L and a right mold plate 43R. The left mold plate 43L is configured to be able to adjust the amount of paving material PV that remains in front of the left rear screed 31L. The right molding plate 43R is configured to be able to adjust the amount of paving material PV that remains in front of the right rear side screed 31R. The paving material PV reaches below the left rear side leveling machine 31L through the gap between the lower end of the left mold plate 43L and the roadbed RB, and reaches below the right rear side leveling machine 31R through the gap between the lower end of the right mold plate 43R and the roadbed RB.

A center road arch device 26 is mounted on the front side leveling machine 30. The center crown device 26 is a mechanism that extends and contracts a turnbuckle installed between the left front side screed 30L and the right front side screed 30R to adjust an angle between a lower surface of the left front side screed 30L (left front side screed plate) and a lower surface of the right front side screed 30R (right front side screed plate) when viewed from the rear. Specifically, the center road arch device 26 rotates the hydraulic motor in accordance with a control command from the controller 50, thereby rotating the body of the turnbuckle and extending and contracting the turnbuckle.

A slope arch device 27 is mounted between the front side screed 30 and the rear side screed 31. The slope arch device 27 includes a left slope arch device 27L and a right slope arch device 27R. Specifically, a left slope arch device 27L is mounted between the left front side screed 30L and the left rear side screed 31L, and a right slope arch device 27R is mounted between the right front side screed 30R and the right rear side screed 31R.

The left slope crown device 27L is a mechanism that extends and contracts turnbuckles installed between the left front side screed 30L and the left rear side screed 31L to adjust an angle between the lower surface of the left front side screed 30L (left front side screed plate) and the lower surface of the left rear side screed 31L (left rear side screed plate) when viewed from the rear. Specifically, the left slope arching device 27L rotates the hydraulic motor in accordance with a control command from the controller 50, thereby rotating the body of the turnbuckle and extending and contracting the turnbuckle. The same applies to the right slope arch device 27R.

The screed footrests 42 are members that constitute footrests for the worker when working at the rear of the screed 3.

An operator who is provided with the asphalt finisher 100 at an upper portion of the tractor 1 can use the guide rail 1G as a handrail. The operators of the asphalt finisher 100 include an operator who operates the tractor 1, an operator who operates the finisher 3, and the like. Further, an information acquisition device 51 is mounted on the guide rail 1G. The information acquisition device 51 may be attached to the canopy or may be directly attached to the main body of the tractor 1. The information acquisition device 51 may be attached to the front side leveling machine 30 or the rear side leveling machine 31.

The information acquisition device 51 is configured to be able to acquire information relating to the surface of the paving material PV compacted by the screed 3. In the present embodiment, the information acquisition device 51 is a LIDAR configured to be able to measure the distance to an object existing around the asphalt finisher 100, and includes a space existing behind the finisher 3 as a measurement range.

For example, as shown in fig. 2, the measurement range of the LIDAR is set so that a height difference that can be formed between the center placement surface CP and the side placement surface SP having the width W1 can be reliably detected. The side surface SP includes a left side surface LP having a width W2 and a right side surface RP having a width W3. The height difference LD shown by a solid line in fig. 2 is an example of the height difference formed between the center mounting surface CP and the left side mounting surface LP.

The measurement range of the LIDAR is set to, for example, a range including a paved surface having a width larger than the width of the front side leveler 30 (i.e., the width W1 of the center paved surface CP). The LIDAR is configured to be able to measure a distance between each of 100 ten thousand or more points in a measurement range and the LIDAR (reference point), for example. Ranges Z0 to Z2 shown by a one-dot chain line in fig. 2 show 3 examples of the measurement range of the LIDAR. In fig. 2, for clarity, the range Z0 is shown at a position farther than the ranges Z1 and Z2 from the asphalt finisher 100 so as not to overlap the ranges Z1 and Z2. However, the positional relationship in the vehicle length direction of the ranges Z0 to Z2 in fig. 2 does not show an actual positional relationship. In practice, ranges Z0 to Z2 are preferably disposed at positions close to asphalt finisher 100 as long as the height difference can be detected.

The range Z0 is set to include the entire width of the new pavement NP, which is the pavement laid by the asphalt finisher 100. The range Z1 is set to include a width that is wider than the width of the front side screed 30, but does not include the entire width of the newly installed pavement NP.

Range Z2 is set to include 4 separate ranges, range Z2a, range Z2b, range Z2c, and range Z2 d. Specifically, the range Z2a and the range Z2b are arranged to detect a height difference that can be formed between the center mounting surface CP and the left side mounting surface LP. The range Z2c and the range Z2d are arranged to detect a height difference that can be formed between the center paved surface CP and the right side paved surface RP. More specifically, the range Z2a is configured to detect a level difference that can be formed by the left end portion of the left front side screed 30L (hereinafter, referred to as "left outer level difference"). Typically, the left outer level difference is formed when the left side pavement LP is higher than the central pavement CP. The range Z2b is configured to detect a level difference that can be formed by the right end portion of the left rear side leveler 31L (hereinafter, referred to as "left inside level difference"). Typically, the left inner level difference is formed when the central pavement CP is higher than the left side pavement LP. The range Z2c is configured to detect a level difference (hereinafter, referred to as "right inside level difference") that can be formed by the left end portion of the right rear side leveler 31R. Typically, the right inner level difference is formed when the central decking surface CP is higher than the right side decking surface RP. The range Z2d is configured to detect a level difference that can be formed by the right end portion of the right front side leveler 30R (hereinafter, referred to as "right outside level difference"). Typically, the right lateral elevational difference is formed when the right lateral decking surface RP is higher than the central decking surface CP.

The information acquisition device 51 may be a monocular camera, a stereo camera, a millimeter wave radar, an ultrasonic sensor, a laser radar, a laser scanner, a depth camera, a laser range finder, or the like.

In the present embodiment, 1 information acquisition device 51 is attached to the asphalt finisher 100, but a plurality of information acquisition devices 51 may be attached to the asphalt finisher 100.

The display device 52 is configured to display information related to the asphalt finisher 100. In the present embodiment, the display device 52 is a liquid crystal display provided in front of the driver' S seat 1S.

The communication device 53 is configured to control communication between the asphalt finisher 100 and equipment existing outside the asphalt finisher 100. In the present embodiment, the communication device 53 is provided in front of the driver' S seat 1S.

Next, a leveling machine elevating system LS mounted on the asphalt finisher 100 will be described with reference to fig. 3 and 4. Fig. 3 is a block diagram showing a configuration example of the leveler elevating system LS. Fig. 4 is a cross-sectional view of the new pavement NP, showing a state when a vertical surface including the alternate long and short dash line SE of fig. 2 is viewed from the + X side.

The leveling machine elevating system LS is mainly composed of a center crown device 26, a slope crown device 27, a leveling cylinder 28, a leveling machine elevating device 29, a controller 50, an information acquiring device 51, a display device 52, a communication device 53, and the like.

The controller 50 includes an information acquisition section 50a, an arch device driving section 50b, a leveling cylinder driving section 50c, and a leveler lifting device driving section 50d as functional elements. For convenience of explanation, the information acquisition unit 50a, the crown device drive unit 50b, the leveling cylinder drive unit 50c, and the leveler lift drive unit 50d are shown separately, but may be configured by software components or hardware components that are shared in whole or in part without being physically distinguished.

The information acquiring unit 50a is configured to be able to acquire information on the surface of the newly installed pavement NP. In the present embodiment, the information acquisition unit 50a measures the finished shape of the surface of the newly installed pavement NP based on the output of the LIDAR as the information acquisition device 51. Specifically, the information acquiring unit 50a measures the finished shape of the surface of the new pavement NP using the local coordinate system centered on the LIDAR and the reference coordinate system. That is, the information acquiring unit 50a converts the coordinates in the local coordinate system into the coordinates in the reference coordinate system, thereby specifying the coordinates in the reference coordinate system corresponding to each point on the surface of the newly installed pavement NP. The reference coordinate system is, for example, a world geodetic coordinate system. The world geodesic coordinate system is a three-dimensional rectangular XYZ coordinate system in which an origin is placed at the center of gravity of the earth, the X axis is taken in the direction of the intersection of the greenwich meridian and the equator, the Y axis is taken in the direction of 90 degrees from the east, and the Z axis is taken in the direction of the north pole.

The information acquiring unit 50a is configured to be able to measure the finished shape of the surface of the newly installed pavement NP within the measurement range during the construction, that is, while the asphalt finisher 100 is moving forward.

In the present embodiment, the information acquisition unit 50a sets a point on the feature AP located on the outer side in the width direction of the new pavement NP as the reference point R1. The reference point R1 is set at the upper end of the L-shaped curb dividing the new pavement NP. However, the ground object AP may be another member such as a wood frame for dividing the newly installed pavement NP. Alternatively, the information acquisition unit 50a may set an imaginary point that is not on the feature AP, such as a point that is located vertically above and at a predetermined height from the upper end of the curb, as the reference point R1.

Specifically, the information acquiring unit 50a detects a curb based on the output of the laser radar, and sets the upper end of the curb located at a position separated by a predetermined distance in the-X direction from the rear end of the asphalt finisher 100 as a reference point R1.

Then, the information acquiring unit 50a sets a line parallel to the width direction (Y-axis direction) of the new pavement NP passing through the reference point R1 as a virtual horizontal line VS. Typically, the imaginary horizontal line VS is a horizontal line passing through the reference point R1.

Then, the information acquiring unit 50a derives the vertical distance between the virtual horizontal rope VS and the surface of the newly installed pavement NP. In the present embodiment, the information acquiring unit 50a sets a plurality of points (for convenience, 19 points P1 to P19) at equal intervals on the virtual horizontal line VS. Then, points Q1 to Q19 existing on the surface of the newly installed pavement NP just below the points P1 to P19 are identified. Specifically, the information acquiring unit 50a determines the points Q1 to Q19 from the distances between each point on the surface of the new pavement NP output from the LIDAR and the LIDAR.

Then, the information acquiring section 50a calculates a distance D1 between the point P1 and the point Q1. In the present embodiment, the information acquiring unit 50a calculates the distance D1 from the distance between the point P1 and the LIDAR and the distance between the point Q1 and the LIDAR, which are output from the LIDAR. The same applies to the distances D2 to D19. The information acquiring unit 50a may calculate the thickness of the new pavement NP corresponding to the distances D1 to D19, respectively, from the height of the road bed RB derived from the reference point R1.

The points set on the virtual horizontal strings VS may be arranged at unequal intervals. The number of dots may be less than 19, or 20 or more.

Then, the information acquiring unit 50a displays the measurement results of the distances D1 to D19 on the display device 52. In the present embodiment, the information acquiring unit 50a displays the measurement results of the distances D1 to D19 on the display device 52 using a graph. However, the information acquiring unit 50a may display the measurement results of the distances D1 to D19 by numerical values alone or by a combination of graphs and numerical values. Alternatively, the information acquiring unit 50a may be configured to display information related to the measurement result only when it is determined that the measurement result is abnormal.

The information acquiring unit 50a can determine whether or not there is a level difference on the paved surface based on the measurement results of the distances D1 to D19. For example, when the difference between the distances of adjacent points (for example, the difference between the distance D8 from the point P8 and the distance D9 from the point P9) is equal to or greater than a predetermined value, the information acquisition unit 50a determines that the difference LD between the point P8 and the point P9 is high. At this time, the information acquiring unit 50a may display the determination result of whether there is a level difference on the display device 52. When it is determined that there is a level difference, the information acquiring unit 50a may display information related to the position of the level difference.

The information acquiring unit 50a may determine whether there is a step by performing image processing on an image captured by an imaging device serving as the information acquiring device 51. The imaging device is, for example, a monocular camera, a stereo camera, an infrared camera, a depth camera, a laser radar, or the like. The image processing includes, for example, binarization processing, edge detection processing, hough transform processing, and the like. In this case, the imaging range of the imaging device may include at least a range in which the bed surface is represented by a range Z2 in fig. 2.

The information acquiring unit 50a may transmit calculation results such as measurement results of the distances D1 to D19 and determination results of whether or not there is a difference in level to the external device. For example, the information acquiring unit 50a may transmit the calculation result to a management device such as a server provided in an external management center or the like or a support device such as a smartphone carried by a worker. This is to display the same information as the information displayed on the display device 52 on a display device attached to the management device or the support device.

The information acquiring unit 50a may calculate the difference between the distance D1 and the ideal distance D1T corresponding to the distance D1 as the unevenness of the surface of the newly installed pavement NP, and output the size of the unevenness as the measurement result. The ideal distance D1T is stored in advance in a nonvolatile storage device, for example. When the distance D1 coincides with the ideal distance D1T, the height of the point on the surface of the new pavement NP corresponding to the distance D1 is equal to the reference height determined from the feature AP. The same applies to the distances D2 to D19. At this time, the information acquiring unit 50a can display the sizes of the irregularities corresponding to the distances D1 to D19 on the display device 52 together with the measurement results of the distances D1 to D19. Alternatively, the information acquiring unit 50a may display the sizes of the irregularities corresponding to the distances D1 to D19 on the display device 52 instead of the measurement results of the distances D1 to D19. The information acquiring unit 50a may display the size of the unevenness on the display device 52 using a graph.

When the size of the irregularities on the surface of the newly installed pavement NP exceeds a predetermined value, the information acquiring unit 50a can display the size on the display device 52. At this time, the information acquiring unit 50a may output an alarm from a sound output device not shown.

The controller 50 may display on the display 52 images taken by a camera (not shown) mounted on the asphalt finisher 100 and capturing images of the rear of the asphalt finisher 100. The information acquiring unit 50a may display information on the measurement results of the distances D1 to D19 superimposed on the image acquired by the camera. In this case, the information on the measurement results of the distances D1 to D19 may be, for example, a numerical value or a graph indicating the size of the unevenness, or a graph indicating the level difference.

When the finished shape of the surface of the newly installed mat NP is continuously measured in the traveling direction (X-axis direction) of the asphalt finisher 100, the information acquiring unit 50a may display a map indicating at least one of the distribution of the sizes of the irregularities on the surface, the presence or absence of a level difference on the surface, and the like on the display device 52. In a state where the new pavement NP is viewed from directly above, the illustration includes at least one of a pattern in which the concave portions are represented by red and the convex portions are represented by blue, a pattern in which the height difference is represented by a straight line, and the like.

The arch device driving unit 50b is configured to drive at least one of the center arch device 26 and the slope arch device 27. In the present embodiment, the road arch device driving unit 50b operates the center road arch device 26 and the slope road arch device 27 independently by using a hydraulic pump, a hydraulic motor, a control valve, and the like. Specifically, the road arch device driving unit 50b operates the center road arch device 26 and the slope road arch device 27 independently in response to a command from an operator of the asphalt finisher 100 via an input device not shown. The arch device driving unit 50b may independently and autonomously operate the center arch device 26 and the slope arch device 27 in response to a control command from the controller 50, separately from a command issued by an operator.

The leveling cylinder driving portion 50c is configured to drive the leveling cylinder 28. The leveling cylinder driving unit 50c operates the leveling cylinder 28 by a hydraulic pump, a control valve, and the like. Specifically, the leveling cylinder drive unit 50c operates the leveling cylinder 28 in response to a command from an operator of the asphalt finisher 100 via an input device. The leveling cylinder driving unit 50c may autonomously operate the leveling cylinder 28 in accordance with a control command from the controller 50, separately from a command issued by an operator.

The leveler lifter driving part 50d is configured to drive the leveler lifter 29. The screed elevating device 29 is a mechanism for moving the rear side screed 31 up and down in order to eliminate a difference in elevation formed between the paved surface compacted by the front side screed 30 and the paved surface compacted by the rear side screed 31. Elimination of the step difference means that the step difference detected by the controller 50 is prevented from subsequently continuing to form as well. The formed height difference is removed, for example, using a harrow for leveling work, a road roller, a flat compactor, or the like.

The leveler elevator drive unit 50d operates the leveler elevator 29 using a hydraulic pump, a hydraulic motor, a control valve, and the like. Specifically, the leveler elevator drive unit 50d operates the leveler elevator 29 in response to a command from the operator of the asphalt finisher 100 via the input device. The leveler elevator drive unit 50d may autonomously operate the leveler elevator 29 in accordance with a control command from the controller 50, separately from a command issued by the operator.

For example, an operator who observes the measurement results of the distances D1 to D19 displayed on the display device 52 can operate the center arch device 26 via the input device and the arch device driving unit 50 b. This is to adjust the angle between the lower surface of the left front screed plate and the lower surface of the right front screed plate when viewed from behind.

For example, when it is detected that the thickness of the left side portion (+ Y side portion) of the new pavement NP formed by the left rear side screed 31L becomes thicker toward the outside, the controller 50 may output a control command to the road arch device driving part 50 b. At this time, the arch device driving unit 50b executes the adjustment by the left slope arch device 27L in accordance with a control command from the controller 50.

The operator who has observed the measurement results of the distances D1 to D19 can operate the leveling cylinder 28 via the leveling cylinder driving unit 50c in addition to the center arch device 26 and the slope arch device 27 in order to adjust the thickness of the newly installed pavement NP. This is because, when the thickness of the newly installed pavement NP is adjusted, the adjustment by the leveling cylinder is more effective than the adjustment by the center road arch device 26 and the slope road arch device. The operator who observes the information notifying the presence of the step may operate the leveler elevating device 29 to eliminate the step.

When it is detected that a level difference is generated between the paved surface formed by the front side leveler 30 and the paved surface formed by the rear side leveler 31, the controller 50 may output a control command to the leveler lifter driving part 50d, for example. At this time, the leveler elevator drive unit 50d operates the leveler elevator 29 in accordance with a control command from the controller 50 to eliminate the step. Specifically, the screed lifter driving section 50d moves the left rear side screed 31L up and down, for example, by operating the screed lifter 29, in order to eliminate a difference in level formed between the paved surface compacted by the left front side screed 30L and the paved surface compacted by the left rear side screed 31L. More specifically, the screed elevation device driving section 50d rotates a screed elevation motor, which is a hydraulic actuator, constituting the screed elevation device 29, in accordance with a control command from the controller 50, and drives a rotation/linear motion converting mechanism attached to the left rear side screed 31L to move the left rear side screed 31L up and down.

As described above, the controller 50 may autonomously control at least one of the center arch device 26, the slope arch device 27, the leveling cylinder 28, and the leveler elevator device 29. Alternatively, the operator may manually control at least one of the center arch device 26, the slope arch device 27, the leveling cylinder 28, and the screed hoist device 29 while confirming the contents displayed on the display device 52.

Next, a screen GX displayed on the display device 52 by the controller 50 when the controller 50 detects a level difference formed between the center paving surface CP and the side paving surface SP will be described with reference to fig. 5A to 5C. Fig. 5A to 5C show 3 display examples of the screen GX. Specifically, fig. 5A is a screen GX displayed when a level difference formed by the right end portion of the left rear side screed 31L and a level difference formed by the right end portion of the right front side screed 30R are detected. Fig. 5B is a screen GX displayed when a level difference formed by the left end portion of the left front side leveler 30L is detected. Fig. 5C is a screen GX displayed when a level difference formed by the left end portion of the right rear side leveler 31R is detected.

The screen GX shown in fig. 5A to 5C includes a body pattern GM, a road paving material pattern GP, and a road surface pattern GR as common patterns.

The body pattern GM represents a top view of the asphalt finisher 100. In the present embodiment, the body pattern GM is a plan view pattern of a portion located further rearward than the screw SC.

Paving material pattern GP represents a top view pattern of paving material PV prior to compaction by screed 3. In the present embodiment, the paving material pattern GP is represented by a thick (thin) pearskin pattern.

The road surface pattern GR represents a plan view pattern of the newly installed pavement NP. In the present embodiment, the road surface pattern GR is expressed by a fine (thick) pearskin pattern.

FIG. 5A includes graphs G11, G12, G21, and G22. The graph G11 represents the left inside step formed by the right end portion of the left rear side leveler 31L. In the present embodiment, the graph G11 is indicated by a thick dotted line. The level difference LD shown by the solid line in fig. 2 is an example of the left inner level difference. The left inner level difference is formed when the level of the paved surface compacted by the left front side leveler 30L is higher than the paved surface compacted by the left rear side leveler 31L.

The graph G12 shows the right outside step formed by the right end portion of the right front side leveler 30R. In the present embodiment, the graph G12 is indicated by a thick dotted line. The right outside level difference is formed when the level of the paved surface compacted by the right front side leveler 30R is lower than the paved surface compacted by the right rear side leveler 31R.

The graph G21 is displayed when a left inside level difference is detected. In the present embodiment, the graphic G21 is a dialog box including text information relating to measures to be taken to eliminate the difference in level between the left and inner sides, and points to the position of the graphic G11. The graphic G21 displays, for example, a text message "lift left", whereby the operator of the asphalt finisher 100 can be notified of the fact that the left rear leveler 31L is autonomously lifted by the controller 50.

The graph G22 is displayed when a right outside step is detected. In the present embodiment, the graphic G22 is a dialog box including text information relating to measures to be taken to eliminate the difference in level between the right and outer sides, and points to the position of the graphic G12. The graphic G22 displays, for example, a text message "lower right", whereby the operator of the asphalt finisher 100 can be notified of the fact that the right rear leveler 31R is autonomously lowered by the controller 50.

FIG. 5B includes graphs G13 and G23. The graph G13 represents the left outside step formed by the left end portion of the left front side screed 30L. In the present embodiment, the graph G13 is indicated by a thick dotted line. The left outer level difference is formed when the height of the paved surface compacted by the left front side leveler 30L is lower than the height of the paved surface compacted by the left rear side leveler 31L.

The graph G23 is displayed when a left outside level difference is detected. In the present embodiment, the graphic G23 is a dialog box including text information relating to measures to be taken to eliminate the difference in level between the left and right sides, and points to the position of the graphic G13. The graphic G23 displays, for example, a text message "lower left", whereby the operator of the asphalt finisher 100 can be notified of the fact that the left rear leveler 31L is autonomously lowered by the controller 50.

FIG. 5C includes graphs G14 and G24. The graph G14 shows the right inside level difference formed by the left end portion of the right rear side leveler 31R. In the present embodiment, the graph G14 is indicated by a thick dotted line. The right inner level difference is formed when the level of the paved surface compacted by the right front side leveler 30R is higher than the paved surface compacted by the right rear side leveler 31R.

The graph G24 is displayed when a right inside step is detected. In the present embodiment, the graphic G24 is a dialog box including text information relating to measures to be taken to eliminate the difference in level between the right and inner sides, and points to the position of the graphic G14. The graphic G24 displays, for example, a text message "lift right", and thereby can notify the operator of the asphalt finisher 100 of the fact that the right rear leveler 31R is autonomously lowered by the controller 50.

Next, a process of adjusting the height of the rear side leveling machine 31 by the controller 50 in order to eliminate a difference in height formed between the central paving surface CP and the side paving surfaces SP (hereinafter, referred to as "height adjustment process") will be described with reference to fig. 6. Fig. 6 is a flowchart of the height adjustment process. For example, the controller 50 repeatedly executes the height adjustment process at a prescribed control cycle while the asphalt finisher 100 is advancing.

First, the controller 50 determines whether there is a high difference in level between the left and outer sides (step ST 1). In the present embodiment, the information acquisition unit 50a of the controller 50 determines whether or not there is a left outer level difference based on the output of the LIDAR as the information acquisition device 51.

When it is determined that there is the left outer level difference (yes at step ST1), the controller 50 lowers the left rear side screed 31L (step ST 2). This is to eliminate the left outer level difference by lowering the left side pavement LP higher than the center pavement CP to align the height of the left side pavement LP with that of the center pavement CP. In the present embodiment, the information acquisition section 50a of the controller 50 outputs a control command for lowering the left rear side screed 31L to the screed lifter driving section 50 d. The screed lifter driving section 50d operates the left screed lifter 29L to lower the left rear side screed 31L in accordance with the control command from the information acquisition section 50 a.

When it is determined that there is no difference in level of the left outer side high (no at step ST1), the controller 50 determines whether there is a difference in level of the left inner side high (step ST 3). In the present embodiment, the information acquisition unit 50a of the controller 50 determines whether or not there is a left inner height difference based on the output of the LIDAR as the information acquisition device 51.

When it is determined that there is a high level difference of the left inner side (yes at step ST3), the controller 50 lifts the left rear side leveler 31L (step ST 4). This is to eliminate the left inner level difference by lifting the left side pavement LP lower than the central pavement CP to align the height of the left side pavement LP with that of the central pavement CP. In the present embodiment, the information acquisition section 50a of the controller 50 outputs a control command for lifting the left rear side leveler 31L to the leveler lifting device driving section 50 d. The screed lifter driving section 50d operates the left screed lifter 29L to lift the left rear side screed 31L in accordance with the control command from the information acquisition section 50 a.

The controller 50 may be configured to determine whether there is a left outer step after determining whether there is a left inner step.

Then, the controller 50 determines whether there is a high difference in level of the right outer side (step ST 5). In the present embodiment, the information acquisition unit 50a of the controller 50 determines whether or not there is a right outer level difference based on the output of the LIDAR as the information acquisition device 51.

When it is determined that there is a high step difference on the right outer side (yes at step ST5), the controller 50 lowers the right rear side leveler 31R (step ST 6). This is to eliminate the right outer level difference by lowering the right side pavement RP higher than the center pavement CP and aligning the height of the right side pavement RP with that of the center pavement CP. In the present embodiment, the information acquisition section 50a of the controller 50 outputs a control command for lowering the right rear side leveler 31R to the leveler lifting device drive section 50 d. The screed lifter driving section 50d operates the right screed lifter 29R to lower the right rear side screed 31R in accordance with the control command from the information acquisition section 50 a.

When it is determined that there is no difference in level of the right outer side high (no at step ST5), the controller 50 determines whether there is a difference in level of the right inner side high (step ST 7). In the present embodiment, the information acquisition unit 50a of the controller 50 determines whether or not there is a difference in right-inner height based on the output of the LIDAR as the information acquisition device 51.

When it is determined that there is a level difference of the right inner side high (yes at step ST7), the controller 50 lifts the right rear side leveler 31R (step ST 8). This is to eliminate the right inner side level difference by lifting the right side pavement RP lower than the center pavement CP to align the height of the right side pavement RP with that of the center pavement CP. In the present embodiment, the information acquisition section 50a of the controller 50 outputs a control command for lifting the right rear side leveler 31R to the leveler lifting device drive section 50 d. The screed lifter driving section 50d operates the right screed lifter 29R to lift the right rear side screed 31R in accordance with the control command from the information acquisition section 50 a.

The controller 50 may be configured to determine whether or not there is a right inner height difference, and then determine whether or not there is a left outer height difference.

The controller 50 may determine whether or not there is a left inside height difference and a left outside height difference after determining whether or not there is a right inside height difference and a right outside height difference, or may determine whether or not there is a left inside height difference, a left outside height difference, a right inside height difference, and a right outside height difference in an arbitrary order.

According to the above configuration, the controller 50 can prevent the step formed between the central paved surface CP and the side paved surfaces SP from continuing over a long distance.

Next, the operation of the leveling machine 3 when the step LD (see fig. 2), which is an example of the step of the left inner side, is eliminated will be described with reference to fig. 7A to 7D. Fig. 7A to 7D are side views of the leveling machine 3 and the newly installed mat NP of fig. 2 when the newly installed mat NP is viewed from the + Y side. However, in fig. 7A to 7D, for the sake of clarity, most of the illustration of the screed 3 is omitted except for the left front screed plate 30LP of the left front screed 30L and the left rear screed plate 31LP of the left rear screed 31L. In addition, the following description relates to the case of lifting the left rear side screed 31L, but the same can be applied to the case of lowering the left rear side screed 31L, the case of lifting the right rear side screed 31R, and the case of lowering the right rear side screed 31R.

Specifically, fig. 7A is a diagram when the controller 50 detects the difference in level LD and starts lifting the left rear side leveler 31L. Fig. 7B is a diagram when the controller 50 lifts the left rear side leveler 31L. Fig. 7C is a diagram when the controller 50 ends the ascent of the left rear side leveler 31L. Fig. 7D is a view of a pavement formed without a step.

As shown in fig. 7A, when the level difference LD having the length L0 in the X-axis direction is detected as the left inner level difference, the controller 50 operates the left screed raising and lowering device 29L and starts to raise the left rear screed 31L in the direction indicated by the arrow AR 1. At the time of fig. 7A, the magnitude of the level difference LD corresponding to the difference between the height of the rear end portion of the left front screed plate 30LP and the height of the rear end portion of the left rear screed plate 31LP is the value DP 1. Further, the swallowing angle β of the left rear leveler plate 31LP becomes larger than the swallowing angle α of the left front leveler plate 30 LP.

Then, as shown in fig. 7B, the controller 50 continues to lift the left rear screed 31L in the direction indicated by the arrow AR2 until the height of the rear end portion of the left front screed plate 30LP coincides with the height of the rear end portion of the left rear screed plate 31 LP. In the present embodiment, the controller 50 raises the left rear side screed 31L at a predetermined raising speed regardless of the value DP1 that is the magnitude of the level difference LD at the time of starting the raising of the left rear side screed 31L. However, the controller 50 may determine the target ascent speed and the target ascent width from the value DP 1. At the time point in fig. 7B, the magnitude of the level difference LD becomes a value DP2 smaller than the value DP 1.

Then, if the rise width of the left rear side leveler 31L reaches the target rise width, the controller 50 stops the rise of the left rear side leveler 31L as shown in fig. 7C. The height difference LD is eliminated when the length in the X-axis direction reaches a value L1. At the time point of fig. 7C, the magnitude of the height difference LD becomes zero.

Then, the controller 50 maintains the height of the left rear side screed 31L when stopping the ascent of the left rear side screed 31L. As a result, as shown in fig. 7D, the asphalt finisher 100 can form a pavement having no level difference.

According to the above configuration, the asphalt finisher 100 can autonomously move the rear side finisher 31 up and down so as to eliminate the difference in level formed between the central paved surface CP and the side paved surface SP, after automatically detecting the difference in level. Therefore, the length of the step in the traveling direction can be prevented from becoming excessively long. As a result, the asphalt finisher 100 can improve work efficiency by reducing work for removing the formed level difference.

Further, the asphalt finisher 100 can form a mat with a small difference in height without receiving the skill of the operator involved in the manual operation of the finisher lifting device 29. Therefore, the asphalt finisher 100 can maintain the quality of the formed pavement at a certain level or more.

As described above, the asphalt finisher 100 according to the embodiment of the present invention includes the tractor 1, the hopper 2 that is provided on the front side of the tractor 1 and that accommodates the paving material, the conveyor belt CV that supplies the paving material in the hopper 2 to the rear side of the tractor 1, the screw SC that spreads the paving material supplied by the conveyor belt CV on the rear side of the tractor 1, the finisher 3 that compacts the paving material spread by the screw SC on the rear side of the screw SC, the information acquiring device 51 that acquires information on the surface of the paving material compacted by the finisher 3, and the controller 50 that is a control device. The leveler 3 includes a front leveler 30 and a rear leveler 31 arranged in a staggered manner in the vehicle length direction. Further, the controller 50 is configured to determine whether there is a level difference formed between the surface of the paving material compacted by the front side screed 30 and the surface of the paving material compacted by the rear side screed 31, based on the information acquired by the information acquiring device 51.

With this configuration, the asphalt finisher 100 can detect the formation of the level difference at an early stage, and therefore can suppress a decrease in the quality of the formed paved surface.

The information acquisition device 51 is preferably mounted to the awning or tractor 1. With this configuration, the asphalt finisher 100 can improve the accuracy of measuring the finished shape of the surface of the newly installed pavement NP. This is because the awning and the tractor 1 both vibrate less than the evener 3. However, the information acquiring device 51 may be installed to the leveler 3. At this time, the information acquiring device 51 can acquire the information related to the surface of the paving material compacted by the screed 3 at a position close to the surface of the paving material.

The asphalt finisher 100 preferably includes a controller 50 as a control device that calculates irregularities on the road surface with respect to a reference height set based on the feature AP or determines whether there is a level difference based on the output of the information acquisition device 51. With this configuration, the asphalt finisher 100 can easily measure the finished shape of the surface of the new pavement NP by itself without connecting to another device, and can easily determine whether or not there is a step on the surface of the new pavement NP. The information acquisition device 51 may be used to realize other functions such as rear monitoring. Further, the operator of the asphalt finisher 100 can intuitively grasp the state of the finished shape of the surface of the newly installed mat NP by observing the information on the unevenness of the surface of the newly installed mat NP with respect to the reference height.

The asphalt finisher 100 preferably has a display function of displaying a result of calculation by the controller 50. The display function is realized by a display device 52 mounted on the asphalt finisher 100, a display device attached to a management device such as a computer installed in an external management center, or a display device attached to a support device such as a smartphone carried by a worker. With this configuration, the asphalt finisher 100 can notify the operator of the asphalt finisher 100 or the worker working around the asphalt finisher 100 of information related to the newly installed pavement NP.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. The above embodiments can be applied to various modifications, replacements, and the like without departing from the scope of the present invention. The features described with reference to the above embodiments can be combined as appropriate as long as they are technically not contradictory.

For example, the asphalt finisher 100 may include a front side leveler elevator device that moves the front side leveler 30 up and down separately from the leveler elevator device 29 that moves the rear side leveler 31 up and down. At this time, the asphalt finisher 100 is configured to be capable of moving the left front side finisher 30L and the right front side finisher 30R up and down, respectively.

In the above embodiment, the controller 50 is configured to automatically detect the height difference, and then move the rear side leveling machine 31 up and down to autonomously eliminate the height difference. However, the controller 50 may be configured to prompt the operator to move the rear side leveler 31 up and down, after notifying the operator of the detected level difference. At this time, the controller 50 may support the operator's manual operation of the leveler lifter 29 using at least one of sound, light, vibration, and the like.

This application claims priority based on japanese patent application No. 2019-066680, filed on 29/3/2019, the entire contents of which are incorporated by reference in this specification.

Description of the symbols

1-tractor, 1G-guide, 1S-driver' S seat, 2-hopper, 3-leveler, 3A-leveling arm, 5-rear wheel, 6-front wheel, 25-leveler jack cylinder, 26-center crown device, 27-slope crown device, 28-leveling cylinder, 29-leveler lift device, 30-front side leveler, 31-rear side leveler, 43-molder board, 50-controller, 50 a-information acquisition section, 50 b-crown device drive section, 50 c-leveling cylinder drive section, 50 d-leveler lift device drive section, 51-information acquisition device, 52-display device, 53-communication device, 100-asphalt roll-down machine, AP-ground, CV-conveyor, NP-newly built pavements, PV-paving materials, RB-road beds, SC-screws.

The claims (modification according to treaty clause 19)

1. An asphalt finisher, comprising:

a tractor;

a hopper provided at a front side of the tractor and accommodating paving material;

a conveyor belt that feeds paving material in the hopper to a rear side of the tractor;

a screw spreading paving material supplied by the conveyor belt at a rear side of the tractor;

a leveler that compacts the paving material spread by the screw at a rear side of the screw;

an information acquisition device that acquires information relating to a surface of paving material compacted by the screed; and

a control device for controlling the operation of the motor,

the said evener includes a front side evener and a rear side evener which are arranged in a staggered manner in the vehicle length direction,

the control device determines whether there is a difference in level formed between the surface of the paving material compacted by the front side screed and the surface of the paving material compacted by the rear side screed, based on the information acquired by the information acquisition device.

2. The asphalt finisher according to claim 1,

an actuator for moving the rear side leveling machine up and down,

the control device determines to raise or lower the rear side leveler by the actuator according to a position of the level difference in the vehicle width direction.

3. The asphalt finisher according to claim 1,

the information acquisition device is mounted to the canopy, the tractor, or the leveler.

[ additionally ] the asphalt finisher according to claim 1,

the control device changes the target speed of the rear side leveler in accordance with the magnitude of the step difference.

[ additionally ] the asphalt finisher according to claim 1,

the control device changes a target width of the rear side leveler in accordance with a magnitude of the step difference.

[ additionally ] the asphalt finisher according to claim 1,

the control device calculates a distance to a surface of paving material compacted by the screed machine based on a reference point.

[ additionally ] the asphalt finisher according to claim 1,

the control device calculates distances to the surface of the paving material compacted by the screed at a plurality of positions in a vehicle width direction of the surface of the paving material compacted by the screed.

[ additionally ] the asphalt finisher according to claim 1,

the control device displays the measurement of the distance to the surface of the paving material compacted by the screed on a display device.

[ additionally ] the asphalt finisher according to claim 1,

the control device also displays the sizes of the irregularities corresponding to the distances to the surface of the paving material compacted by the screed, respectively, on a display device.

[ additionally ] the asphalt finisher according to claim 1,

the control device displays the magnitude of the height difference on a display device using a graph.

[ additionally ] the asphalt finisher according to claim 1,

the control device displays information relating to the determination of the distance to the surface of the paving material compacted by the screed, superimposed on the image acquired by the camera device.

Claims

1. An asphalt finisher, comprising:

a tractor;

a control device for controlling the operation of the motor,

2. The asphalt finisher according to claim 1, comprising:

an actuator that moves the rear side leveler up and down,

3. The asphalt finisher according to claim 1,

the information acquisition device is installed in the awning, the tractor or the leveling machine.