JP2020147897A - Asphalt finisher and screed control method - Google Patents

Abstract

To provide an asphalt finisher and a screed control method which can overcome ground unevenness on site so that pavement surface can be finished flat.SOLUTION: An asphalt finisher 1 which has a traveling body 2, a screed 4, a leveling arm 5, a supporting shaft 6, a pivot cylinder 9 and a control device 19 further includes: a first detection part 15 which detects the height of a known first point with respect to the supporting shaft 6; and a second detection part 16 which detects the height of a second point positioned at a predetermined distance from the first point of the leveling arm 5. The control device 19 has a pavement design line 12a and controls the pivot cylinder 9 so as to change the position of the support shaft 6 based on the height change amount of the first point pavement design line detected by the first detection part 15 and the height change amount of the pavement design line of the second point detected by the second detection part 16, and is configured as such that an attack angle α on the bottom of the screed is maintained at a predetermined value.SELECTED DRAWING: Figure 1

Description

The present invention relates to an asphalt finisher and a screed control method for leveling an asphalt mixture in pavement work.

As the final process of the pavement work, there is a work of evenly laying the asphalt mixture, and the work of laying the asphalt mixture is performed by the asphalt finisher.

The outline of the asphalt finisher 1 will be described with reference to FIG.

A hopper 3 for inserting an asphalt mixture is provided at the front portion of the traveling body 2. The asphalt mixture in the hopper 3 was transferred to the rear (right side in FIG. 10) by a feeder (not shown) located at the lower part of the traveling body 2, and then provided in a direction orthogonal to the feeder. It is spread evenly to the left and right by a screw spreader (not shown) and spread by a screed 4.

The screed 4 is fixedly provided at the rear end of the leveling arm 5, and the front end of the leveling arm 5 is connected to the side surface of the traveling body 2 via a support shaft 6. The support shaft 6 is located substantially in the center between the front and rear wheels 7 and 8, and is provided so as to be movable up and down. Further, the support shaft 6 is connected to the pivot cylinder 9 and is moved up and down by the pivot cylinder 9. Due to the vertical displacement of the pivot cylinder 9, the leveling arm 5 and the screed 4 are integrally tilted about the ground contact point of the screed 4.

The screed 4 is towed by the traveling body 2 via the leveling arm 5, and the screed 4 can be freely displaced up and down with the support shaft 6 of the leveling arm 5 as a fulcrum.

The asphalt mixture heated to a predetermined temperature, for example, about 160 ° C. is conveyed by a dump truck or the like and put into the hopper 3. The asphalt mixture is sent to the rear through the center of the traveling body 2 by the feeder, spread in the left-right direction (the width direction of the road) by the screw spreader, and is raised to the front side of the screed 4.

The bottom surface of the screed 4 is inclined so that the front side is raised so that an attack angle (working angle) α is formed.

As the traveling body 2 advances, the asphalt mixture digs into the lower surface of the screed 4, and the weight of the screed 4 presses the asphalt mixture against the road surface, spreads it evenly, and paves the asphalt mixture. Is constructed.

Here, the pavement thickness of the asphalt mixture is determined by the balance of forces such as the viscosity of the asphalt mixture, the temperature of the asphalt mixture, the speed of the traveling body 2, the attack angle α, and the weight of the screed 4. .. Assuming that the viscosity of the asphalt mixture, the temperature of the asphalt mixture, the speed of the traveling body 2, and the weight of the screed 4 do not fluctuate significantly during the pavement construction, the main factor that determines the pavement thickness is the attack angle.

Assuming that the attack angle in a balanced state is α0, if the attack angle α is made larger than α0, the amount of penetration increases and the pavement thickness increases. The attack angle α decreases as the pavement thickness increases, and the pavement thickness stabilizes when the force balance is established (α = α0). Further, when the attack angle is reduced, the amount of digging is reduced, the pavement thickness is reduced, the attack angle α is increased as the pavement thickness is reduced, and the pavement thickness is further balanced (α = α0). Is stable.

The attack angle α increases or decreases due to the vertical displacement of the support shaft 6, and when the support shaft 6 is raised by the pivot cylinder 9, the attack angle α increases and the support shaft 6 is lowered by the pivot cylinder 9. And the attack angle α decreases. Therefore, when increasing or decreasing the pavement thickness, the attack angle α by the pivot cylinder 9 may be increased or decreased. Further, by keeping the attack angle α constant, the pavement thickness can be made flat and constant.

However, the local board (road surface before pavement) is leveled flat by the road roller, but some unevenness (non-landing) remains. Therefore, the traveling body 2 swings when the traveling body 2 rides on and lowers the unevenness. The screed 4 is pulled by the traveling body 2, and the supporting shaft 6 is displaced up and down by swinging the traveling body 2.

Since the vertical displacement of the support shaft 6 appears in the fluctuation of the attack angle α, the pavement thickness fluctuates, and the influence of the non-landing of the local board appears on the pavement surface.

Special Fair 7-49646 Gazette Special Fair 7-96762 Gazette Japanese Unexamined Patent Publication No. 2013-2276 JP-A-2002-339314 Japanese Unexamined Patent Publication No. 2005-121388 U.S. Pat. No. 1,0066,346 Japanese Unexamined Patent Publication No. 9-264743

The present invention provides an asphalt finisher and a screed control method capable of canceling the non-landing of the local board and finishing the pavement surface flat.

The present invention includes a traveling body, a screed pulled by the traveling body, a leveling arm integrally provided with the screed and extending forward, and a leveling arm provided on the traveling body so as to be vertically displaceable. An asphalt finisher including a support shaft connecting a tip portion to the traveling body, a pivot cylinder for moving the support shaft up and down, and a control device, which is in the vicinity of the support shaft of the leveling arm and supports the support. A first detection unit that detects the height of a known first point with respect to the axis, and a second detection unit that detects the height of a second point located at a predetermined distance from the first point of the leveling arm. Further provided, the control device has a pavement design line, and the height change amount ΔA with respect to the pavement design line at the first point detected by the first detection unit and the second detection unit detected by the second detection unit. The pivot cylinder is controlled so that the support shaft is displaced by − (ΔA + ΔB) based on the height change amount ΔB with respect to the pavement design line of the point, and the attack angle α on the bottom surface of the screed is maintained at a predetermined value. It is about the asphalt finisher.

The present invention also relates to an asphalt finisher in which the first detection unit is an ultrasonic sensor provided at the first point and the second detection unit is an ultrasonic sensor provided at the second point. ..

Further, in the present invention, the first detection unit is composed of a receiver provided at the first point and a laser beam that is rotationally irradiated at a constant speed, and the second detection unit is provided at the second point. It is composed of a receiver and the laser beam, the laser beam is composed of a plurality of fan beams, at least one fan beam is inclined at a known angle with respect to a horizontal plane, and when the receiver receives the fan beam. It relates to an asphalt finisher configured to detect the ΔA and the ΔB based on the light receiving time difference of the above.

Further, in the present invention, the first detection unit is composed of a prism provided at the first point and a total station for tracking and measuring the prism, and the second detection unit is a prism provided at the second point and the above. The total station is composed of a total station, and the total station relates to an asphalt finisher configured to alternately measure the prisms, measure the heights of the prisms, and detect the ΔA and the ΔB based on the measurement results.

Further, in the present invention, the first detection unit is composed of a prism provided at the first point and a first total station for tracking and measuring the prism, and the second detection unit is provided at the second point. It is composed of a prism and a second total station, and the first and second total stations are configured to measure the heights of the first and second prisms and detect ΔA and ΔB based on the measurement results. It is about the asphalt finisher that has been made.

Further, in the present invention, either one of the first detection unit and the second detection unit has an inclination sensor for measuring the inclination of the leveling arm, and the inclination angles detected by the inclination sensor, the first point and the first. It relates to an asphalt finisher configured to detect a height based on a distance between two points and a height detected by either the first detection unit or the second detection unit.

Further, the present invention relates to an asphalt finisher which is an ultrasonic sensor, whichever one of the first detection unit and the second detection unit is used.

Further, in the present invention, either one of the first detection unit and the second detection unit is composed of a receiver and a laser beam that is rotationally irradiated at a constant speed, and the laser beam is composed of a plurality of fan beams. At least one fan beam is tilted at a known angle with respect to the horizontal plane, and the receiver relates to an asphalt finisher configured to detect height based on a light receiving time difference when the fan beam is received.

Further, in the present invention, either one of the first detection unit and the second detection unit is composed of a prism and a total station for tracking and measuring the prism, and the total station is configured to measure the height of the prism. It is about the asphalt finisher.

Further, in the present invention, the control device has design data of the entire range of pavement construction as a pavement design line, and the height change amount ΔA and the second detection regarding the design data of the first point detected by the first detection unit. The pivot cylinder is controlled so that the support shaft is displaced by − (ΔA + ΔB) based on the height change amount ΔB regarding the design data of the second point detected by the unit, and the attack angle α on the bottom surface of the screed is maintained at a predetermined value. It is related to the asphalt finisher that is constructed in such a way.

Further, in the present invention, the traveling body further includes a plurality of GNSS for acquiring the geocentric coordinates, and the control device has three-dimensional actual measurement data and design data of the local board in the entire range of the pavement construction, and the GNSS The present invention relates to an asphalt finisher configured to acquire the geocentric coordinates of the construction position and calculate the ΔA and the ΔB by comparing the three-dimensional actual measurement data at the geocentric coordinates with the design data.

Furthermore, the present invention is provided with a traveling body, a screed pulled by the traveling body, a leveling arm integrally provided with the screed and extending forward, and a leveling arm provided on the traveling body so as to be vertically displaceable. An asphalt finisher including a support shaft that connects the tip of the arm to the traveling body, a pivot cylinder that moves the support shaft up and down, and a control device, and is in the vicinity of the support shaft of the leveling arm. The height of a known first point with respect to the support shaft and the height of a second point located at a predetermined distance from the first point of the leveling arm are detected, respectively, and the detected height and the pavement design line are used as described above. The present invention relates to a screed control method for controlling the pivot cylinder so as to detect the height change amount ΔA of the first point and the height change amount ΔB of the second point and displace the support shaft by − (ΔA + ΔB). ..

According to the present invention, a traveling body, a pavement pulled by the traveling body, a leveling arm integrally provided with the screed and extending forward, and a leveling arm provided on the traveling body so as to be vertically displaceable. An asphalt finisher including a support shaft that connects the tip of the arm to the traveling body, a pivot cylinder that moves the support shaft up and down, and a control device, and is in the vicinity of the support shaft of the leveling arm. A first detection unit that detects the height of a known first point with respect to the support shaft, and a second detection unit that detects the height of a second point located at a predetermined distance from the first point of the leveling arm. Further, the control device has a pavement design line, and the height change amount ΔA regarding the pavement design line at the first point detected by the first detection unit and the height change ΔA detected by the second detection unit. The pivot cylinder is controlled so that the support shaft is displaced by − (ΔA + ΔB) based on the height change amount ΔB with respect to the pavement design line at the second point, and the attack angle α on the bottom surface of the screed is maintained at a predetermined value. Therefore, even if the attack angle α increases or decreases due to the swing of the traveling body, it can be immediately corrected, and a flat pavement surface can be realized with high accuracy regardless of the swing of the traveling body.

Further, according to the present invention, the traveling body, the screed pulled by the traveling body, the leveling arm integrally provided with the screed and extending forward, and the traveling body are provided so as to be vertically displaceable. An asphalt finisher including a support shaft that connects the tip of the leveling arm to the traveling body, a pivot cylinder that moves the support shaft up and down, and a control device, and is in the vicinity of the support shaft of the leveling arm. , The height of the first point known to the support shaft and the height of the second point located at a predetermined distance from the first point of the leveling arm are detected, and the detected height and the pavement design line are used. Since the pivot cylinder is controlled so as to detect the height change amount ΔA of the first point and the height change amount ΔB of the second point and displace the support shaft by − (ΔA + ΔB), the bottom surface of the pavement. The attack angle α is maintained at a predetermined value, and an excellent effect is exhibited that a flat pavement surface can be realized with high accuracy regardless of the swing of the traveling body.

It is a schematic block diagram of the 1st Example. It is a control schematic diagram of the 1st Example. It is a schematic block diagram of the 2nd Example. It is explanatory drawing of the 2nd Example. It is explanatory drawing of the 3rd Example. It is explanatory drawing of the 4th Example. It is explanatory drawing of the 5th Example. It is explanatory drawing of 6th Example. (A) and (B) are explanatory views of the seventh embodiment. It is a schematic explanatory drawing of the conventional asphalt finisher.

Hereinafter, examples of the present invention will be described with reference to the drawings.

1 and 2 show an outline of the first embodiment, and the same reference numerals as those shown in FIGS. 1 and 10 are designated by the same reference numerals, and the details thereof will be omitted. Further, in FIG. 1, 11 indicates a local board, 12a indicates a pavement design line, and 12b indicates a pavement surface after pavement construction. In FIG. 1, the unevenness of the local board 11 is exaggerated and displayed.

A leveling arm 5 extends forward from the screed 4, and the tip of the leveling arm 5 is connected to a support shaft 6. The support shaft 6 is supported by a guide 13 so as to be movable in the vertical direction with respect to the traveling body 2. A pivot cylinder 9 is connected to the support shaft 6, and the support shaft 6 is moved in the vertical direction by driving (expanding / contracting) the pivot cylinder 9.

A first detector 15 for detecting the height of point A is provided at a position near the support shaft 6 of the leveling arm 5 and at a known distance from the support shaft 6, and the first detector 15 and the screed are provided. A second detector 16 is provided which detects the height of the point B, which is located between the points 4 and at a known distance from the point A.

The distance between the first detector 15 and the second detector 16 is known, and the distance between the support shaft 6 and the second detector 16 is also known.

The first detector 15 and the second detector 16 can each set 0 points (detection reference points).

Examples of the first detector 15 and the second detector 16 include an ultrasonic height detector and a contact height detector.

In FIG. 2, 19 indicates a control device, and the pivot cylinder 9 is controlled to keep the attack angle α constant or increase / decrease based on the detection results of the first detector 15 and the second detector 16. To do.

The detection results of the first detector 15 and the second detector 16 are transmitted to the control device 19. The control device 19 has a storage unit 20, and the storage unit 20 stores a program for controlling the pivot cylinder 9 and controlling the attack angle α. The control device 19 controls the expansion and contraction of the pivot cylinder 9 by a program.

Although only the left side surface (the left side surface facing the traveling direction) of the asphalt finisher 1 is shown in FIG. 1, the leveling arm 5, the support shaft 6, the pivot cylinder 9, and the first detector 15 are shown. The second detector 16 has the same configuration on the right side surface, and is provided with a leveling arm 5', a support shaft 6', a pivot cylinder 9', a first detector 15', and the second detector 16'. Needless to say, there is.

The detection results of the first detectors 15, 15'and the second detectors 16, 16' are transmitted to the control device 19, and the control device 19 expands and contracts the pivot cylinders 9, 9'based on the detection results. Control individually.

Since the left and right sides are the same, the left side surface will be described below.

The asphalt finisher 1 is paved so that the pavement surface 12b matches the pavement design line 12a.

The first detector 15 and the second detector 16 detect heights from the pavement design line 12a at points A and B, respectively. Examples of the pavement design line 12a include a sensor rope stretched parallel to the upper surface of the curb or the pavement design line 12a and having a known distance (distance) from the pavement design line 12a. ..

In the case where the asphalt finisher 1 is in a flat place and the screed 4 is located on the pavement design line 12a, the attack angle α0 of the set value is obtained in the first detector 15 and the second detector 16. Is set to 0 with reference to. Further, the height of the support shaft 6 with respect to the pavement design line 12a at this time is set to H1, and the line passing through the support shaft 6 and parallel to the pavement design line 12a is set as the virtual reference line 26.

When the traveling body 2 travels (moves to the left in FIG. 1), the front wheels 7 and the rear wheels 8 roll in accordance with the local board 11, so that the running body 2 does not land on the local board 11. Move on, off, and swing.

For example, when the rear wheel 8 does not move up and down and the front wheel 7 gets on and off the land, the support shaft 6 moves downward according to the amount of getting on and off. When the support shaft 6 is located between the front wheels 7 and the rear wheels 8, the support shaft 6 is displaced downward by approximately 1/2 of the amount of loading and unloading. The tip of the leveling arm 5 is also displaced following the displacement of the support shaft 6, and the leveling arm 5 is inclined downward about the ground contact point of the screed 4. Therefore, the attack angle α is reduced.

Further, when the front wheels 7 do not move up and down and the rear wheels 8 get on and off the land, the support shaft 6 is displaced downward by about 1/2 of the amount of getting on and off corresponding to the amount of getting on and off. Therefore, the attack angle α is reduced.

Similarly, when the front wheels 7 and the rear wheels 8 ride on the non-land, the attack angle α increases.

As described above, the pavement thickness increases or decreases as the attack angle α increases or decreases, but in this embodiment, the attack angle is controlled by controlling the pivot cylinder 9 based on the first detector 15 and the second detector 16. Control α to be constant (attack angle α0).

First, when the displacement ΔA is detected only from the first detector 15, it means that the first detector 15 is displaced upward by + ΔA with respect to the pavement design line 12a, and the support shaft 6 is the pavement. It means that the displacement is + ΔA upward with respect to the design line 12a. Therefore, in this state, the attack angle α is increasing. The control device 19 controls the pivot cylinder 9 to displace the support shaft 6 downward (−ΔA) by ΔA, and hold the support shaft 6 at the H1 position with respect to the pavement design line 12a. That is, the attack angle α is controlled to be constant.

Similarly, when the displacement −ΔA is detected only from the first detector 15, it means that the first detector 15 is displaced downward by −ΔA from the pavement design line 12a, and the control device 19 is said to have the displacement −ΔA. The pivot cylinder 9 is controlled to displace the support shaft 6 upward by + ΔA, and the support shaft 6 is held at the H1 position with respect to the pavement design line 12a.

Here, the control for the displacement ΔA at point A cancels the swing amount (vertical movement) when the traveling body 2 swings due to the non-landing of the field board 11, and the support shaft 6 (traction point) is controlled. ) Is controlled to be pulled along the planned line (virtual reference line 26).

Next, when the displacement ΔB is detected only from the second detector 16, it means that the second detector 16 is displaced upward by + ΔB with respect to the pavement design line 12a.

That is, when the displacement ΔB is detected only from the second detector 16, the virtual reference line 26 is offset downward by −ΔB, and the pivot cylinder 9 is controlled. That is, the pivot cylinder 9 displaces the support shaft 6 downward by −ΔB. Since the reference line is offset, it does not affect the first detector 15. Hereinafter, the description of the control for the second detector 16 will refer to the offset of the virtual reference line.

Next, when the displacement −ΔB is detected only from the second detector 16, the virtual reference line 26 is offset upward by + ΔB in the same manner, and the support shaft 6 is moved upward by + ΔB by the pivot cylinder 9. Displace to.

Here, the control for the displacement ΔB at point B is a control for controlling the screed 4 according to the planned line (paving design line 12a) and paving.

Further, the case where the displacement ΔA is detected from the first detector 15 and the displacement ΔB is detected from the second detector 16 at the same time will be described.

When the displacement ΔA and the displacement ΔB are detected at the points A and B at the same time, the control amount is the sum obtained by reversing the signs of the respective displacement amounts. For example, if the displacement amount of + ΔA is detected at the point A and the displacement amount of + ΔB is detected at the point B, the control device 19 offsets the virtual reference line 26 at the point A downward by −ΔB. Due to this offset, the new detected displacement amount at point A becomes ΔA2 = ΔA + ΔB. As the control signal, the sign is inverted and becomes − (ΔA + ΔB).

If the control device 19 moves the support shaft 6 downward by − (ΔA + ΔB) by the pivot cylinder 9 by − (ΔA + ΔB), the attack angle α0 is set with the virtual reference line 26 offset by − (ΔB). realizable.

Summarizing the above, the attack angle α can be controlled to a predetermined value by executing the following measures with respect to the detection results of the first detector 15 and the second detector 16.

1. 1. When the displacement ΔA is detected only from the first detector 15, the control device 19 drives the pivot cylinder 9 to displace the support shaft 6 by −ΔA.

2. 2. When the displacement ΔB is detected only from the second detector 16, the control device 19 drives the pivot cylinder 9 to displace the support shaft 6 by −ΔB.

3. 3. When the displacement ΔA is detected from the first detector 15 and the displacement ΔB is simultaneously detected from the second detector 16, the control device 19 drives the pivot cylinder 9 to make the support shaft 6 − (. ΔA + ΔB) Displace.

Therefore, when the asphalt finisher 1 runs on the local board 11 and there is a swing due to non-landing, the attack angle α can be maintained at the set angle. Further, based on the detection results of the first detector 15 and the second detector 16, the final position of the support shaft 6 is immediately controlled, that is, the set attack angle α is controlled, so that there is no response delay. Highly accurate flatness can be obtained.

In the conventional method, the attack angle α is restored or controlled to the set angle by the balance of the force due to the movement of the traveling body 2, so that a time lag cannot be avoided.

Although wheels are used as the traveling device in the above description, a crawler type traveling device may be used.

3 and 4 show a second embodiment in which the heights of the first detector 15 and the second detector 16 are detected by using the rotary laser device 21. In FIG. 3, the same reference numerals are given to those equivalent to those shown in FIG.

The first detector 15 and the second detector 16 in the second embodiment are composed of a light receiving device. The light receiving device includes a point-shaped light receiver (not shown) and receives a laser beam 22 that is rotationally irradiated at a constant speed. The laser beam 22 is horizontally rotated by the rotating laser device 21, and the laser beam 22 is composed of a plurality of fan beams (3 fan beams 22a, 22b, 22c in the figure). In the figure, the fan beam of 3 is formed in an N shape.

The fan beams 22a, 22b, 22c have a known divergence angle, and at least one fan beam 22b is tilted at a known angle with respect to the horizontal plane. The receiver receives the fan beams 22a, 22b, and 22c, and detects the difference in reception time between the fan beams to determine the distance to the receiver and the height of the receiver with reference to the rotating laser device 21. It can be measured. As for the measurement system using the light receiving device and the rotating laser device, the system shown in JP-A-2005-121388 (Patent Document 5) can be used.

The first detector 15 is provided at the upper end of a support column 24 vertically erected in the vicinity of the support shaft 6 of the leveling arm 5, and a connection point 24a between the support column 24 and the leveling arm 5 and the first detector. The distance between 1 detector 15 (receiver) is known. Further, the distance between the connecting point 24a and the support shaft 6 is also known. Therefore, the distance and positional relationship between the first detector 15 and the support shaft 6 are known.

The second detector 16 is provided at the upper end of a support column 25 vertically erected at a predetermined position of the leveling arm 5. Further, the distance between the connection point 25a between the support column 25 and the leveling arm 5 and the second detector 16 (receiver) is known. Further, the distance between the connecting point 25a and the support shaft 6 is also known. Therefore, the distance and positional relationship between the second detector 16 and the support shaft 6 are known, and the distance between the first detector 15 and the second detector 16 is also known.

In FIG. 4, 23 shows a laser reference plane formed by the laser beam 22, and the height of the laser reference plane 23 is known, for example, a known height with respect to the pavement design line 12a. When the first detector 15 and the second detector 16 receive the laser beam 22, the height positions of the first detector 15 and the second detector 16 with respect to the laser reference surface 23 are measured. , The height position with respect to the connection point 24a and the connection point 25a with respect to the pavement design line 12a is measured, and the fluctuation of the height position is also measured in the same manner.

Therefore, similarly to the first embodiment, the pivot cylinder 9 is controlled so as to maintain the attack angle α at the set angle based on the displacement ΔA of the connecting point 24a and the displacement ΔB of the connecting point 25a.

In the second embodiment, the distance measurement of the first detector 15 and the second detector 16 can be performed with the rotary laser device 21 as a reference. By installing the rotary laser device 21 at known three-dimensional coordinates (geocentric coordinates), the three-dimensional coordinates of the first detector 15 and the second detector 16 can be measured in real time.

Therefore, the control unit of the asphalt finisher 1 stores three-dimensional data (paving design data) of the pavement construction surface over the entire pavement construction range, and the pavement design data and the first detectors 15 and 2 by the rotary laser device 21 are stored. Based on the three-dimensional measurement result of the detector 16, the pavement over the entire pavement construction range can be constructed. The height data of the pavement design data is equivalent to that of the pavement design line 12a.

In the second embodiment, work such as stretching a sensor rope or the like at the pavement construction site can be omitted, and pavement can be easily constructed even on a complicated curved surface.

A GNSS receiver may be provided in the asphalt finisher 1, and the geocentric coordinates of the current position of the asphalt finisher 1 may be acquired in real time based on the reception result of the GNSS receiver.

FIG. 5 shows a third embodiment.

In the third embodiment, the three-dimensional data of the local board 11 over the entire construction range is acquired in advance. Regarding the acquisition of 3D data, either acquire point group data with 3D coordinates using a laser scanner, or mount a camera on a small unmanned vehicle (drone) and acquire a photograph of the entire construction range by photo survey. Whether to acquire the shape of the road surface by acquiring three-dimensional coordinates, or by tracing the road surface with a probe provided with a prism or a survey pole with wheels, and tracking and measuring the prism with a total station (Patent Documents). 7) and the like are appropriately selected, and the three-dimensional data 28 of the local board 11 over the entire construction range is actually measured and acquired (referred to as the three-dimensional actual measurement data 28 of the local board).

Further, as a method for acquiring the three-dimensional actual measurement data of the field board 11, US Pat. No. 1,0066346 (Patent Document 6) can be used.

The measured value is stored in the storage unit of the control unit of the asphalt finisher 1.

In addition, three-dimensional design data over the entire construction range is calculated and created, and the design data 29 is stored in the storage unit.

A plurality of GNSS receivers (not shown) are provided on the asphalt finisher 1, and the GNSS receivers are provided at known positions with respect to the mechanical center (or reference point) of the asphalt finisher 1. Based on the reception result of the GNSS receiver, the geocentric coordinates of the current position of the asphalt finisher 1 can be acquired in real time. From the geocentric coordinates acquired by the GNSS, the geocentric coordinates of the machine center of the asphalt finisher 1 and the pavement construction position can be acquired in real time.

By providing a plurality of the GNSS receivers, the direction of the asphalt finisher 1 with respect to the traveling direction can be measured.

Further, the leveling arm 5 is provided with an ultrasonic sensor as a first detector 15 and a second detector 16, and the first detector 15 and the second detector 16 are used to construct the pavement at the asphalt pavement construction position (current position). Measure the thickness.

The geocentric coordinates of the current position can be measured from the reception result of the GNSS receiver, and the height coordinates of the on-site measured value (three-dimensional coordinates) and the height of the design data (three-dimensional coordinates) at the geocentric coordinates of the current position. Obtain the design pavement thickness at the current position based on the coordinates. The design pavement thickness is compared with the construction pavement thickness, and the pivot cylinder 9 is controlled so that the construction pavement thickness becomes the design pavement thickness. The design pavement thickness serves as a reference for pavement construction and corresponds to the pavement design line 12a.

The control of the pivot cylinder 9 at this time was also described in the first embodiment by obtaining ΔA and ΔB by comparing the detection values of the first detector 15 and the second detector 16 with the design data. Performs the same control as.

Further, as a method for obtaining the height at the points A and B, various methods other than the above-mentioned methods can be considered.

FIG. 6 shows a fourth embodiment, and in the fourth embodiment, a case where a total station 31 having a tracking function is used as a method for obtaining heights at points A and B is shown.

Prism 32, 33 is provided at the upper ends of the columns 24, 25 erected on the leveling arm 5, and the prism 32 and the prism 33 are alternately tracked and measured by the total station 31. Since the total station 31 measures the three-dimensional coordinates of the prisms 32 and 33, the heights at points A and B can be obtained in the same manner.

Since the distance between the columns 24 and 25 is a known distance and the distance to the columns 24 and 25 is measured with high accuracy by the total station 31, the columns 24, centered on the installation point of the total station 31. The horizontal angle between 25 can be obtained with high accuracy by calculation.

Therefore, since the collimation direction may be alternately rotated at the obtained horizontal angle, the tracking state for both prisms 32 and 33 is maintained even when the prism 32 and the prism 33 are alternately collimated at high speed. be able to.

Two total stations are installed, the prism 32 is tracked and measured by the first total station, the prism 33 is tracked and measured by the second total station, and the heights at points A and B are obtained based on the respective measurement results. You may. The first total station and the second total station are installed in a known relationship.

FIG. 7 shows a fifth embodiment, and in the method shown in the fifth embodiment, one ultrasonic sensor and an inclination sensor are provided for the leveling arm 5, and the heights at points A and B are high. Seeking.

An ultrasonic sensor is used as the second detector 16 for detecting the height of point B, and an inclination sensor 35 for detecting the inclination of the leveling arm 5 is provided at a required position of the leveling arm 5. The distance L between the position where the second detector 16 is provided and the support shaft 6 is known.

When the height of point B is detected by the second detector 16, the height of point A can be detected based on the inclination angle and the distance L detected by the inclination sensor 35.

Therefore, the same control as described in the first embodiment can be executed based on the change ΔB in the height of the point B and the change ΔA in the height of the point A.

The height of the point A may be detected by the ultrasonic sensor (first detector 15), and the height of the point B may be calculated based on the height of the point A and the inclination angle detected by the inclination sensor 35. Good.

FIG. 8 shows a sixth embodiment, and in the sixth embodiment, in the method shown in the fifth embodiment, as a height detection method at points A and B (point B is detected in the figure). The method shown in FIGS. 3 and 4 is used.

A support column 25 is erected on the leveling arm 5, and a light receiving device is provided at the upper end as a second detector 16. The second detector 16 receives and detects a rotating laser, and detects the height at point B based on the light receiving result. The height at point A is calculated based on the height at point B, the inclination angle detected by the inclination sensor 35, and the distance L.

FIG. 9 shows a seventh embodiment. In the seventh embodiment, the total station 31 is used as a method for measuring the height of the point A or the point B.

In FIG. 9A, a support column 25 is erected corresponding to the point B of the leveling arm 5, a prism 33 is provided at the upper end, and the total station 31 tracks the prism 33 while performing three-dimensional coordinates. Measure. By measuring the height of the point B, the height of the other point A can be obtained based on the inclination angle and the distance L detected by the inclination sensor 35.

In FIG. 9B, a support column 24 is erected corresponding to the point A of the leveling arm 5, a prism 32 is provided at the upper end, and the height of the point A is measured by the total station 31. Similarly, the height of the other point B can be obtained based on the inclination angle detected by the inclination sensor 35 and the distance L.

The height measurement at points A and B is not limited to the above embodiment, and various other measurement methods can be used. For example, a laser length measuring device is used instead of the ultrasonic sensor.

1 Asphalt finisher 2 Traveling body 4 Screed 5 Leveling arm 6 Support shaft 9 Pivot cylinder 11 Field board 12a Pavement design line 12b Pavement surface 15 1st detector 16 2nd detector 19 Control device 21 Rotating laser device 28 3D actual measurement data 29 Design data 31 Total station 35 Tilt sensor

Claims (12)

A traveling body, a screed pulled by the traveling body, a leveling arm integrally provided with the screed and extending forward, and a leveling arm provided on the traveling body so as to be vertically displaceable, and a tip portion of the leveling arm is provided. An asphalt finisher including a support shaft connected to a traveling body, a pivot cylinder for moving the support shaft up and down, and a control device, which is in the vicinity of the support shaft of the leveling arm and with respect to the support shaft. It further includes a first detection unit that detects the height of a known first point, and a second detection unit that detects the height of a second point located at a predetermined distance from the first point of the leveling arm. The control device has a pavement design line, and the height change amount ΔA regarding the pavement design line at the first point detected by the first detection unit and the pavement design at the second point detected by the second detection unit. An asphalt finisher configured to control the pivot cylinder so that the support shaft is displaced by − (ΔA + ΔB) based on the height change amount ΔB with respect to the wire, and the attack angle α on the bottom surface of the pavement is maintained at a predetermined value. The asphalt finisher according to claim 1, wherein the first detection unit is an ultrasonic sensor provided at the first point, and the second detection unit is an ultrasonic sensor provided at the second point. The first detection unit is composed of a light receiver provided at the first point and a laser beam that is rotationally irradiated at a constant speed, and the second detection unit is a light receiver provided at the second point and the laser. Composed of light rays, the laser beam is composed of a plurality of fan beams, at least one fan beam is tilted at a known angle with respect to the horizontal plane, and the receiver is based on the light receiving time difference when receiving the fan beam. The asphalt finisher according to claim 1, which is configured to detect the ΔA and the ΔB. The first detection unit is composed of a prism provided at the first point and a total station for tracking and measuring the prism, and the second detection unit is composed of a prism provided at the second point and the total station. The asphalt finisher according to claim 1, wherein the total station alternately measures the prisms, measures the heights of the prisms, and detects the ΔA and the ΔB based on the measurement results. The first detection unit is composed of a prism provided at the first point and a first total station for tracking and measuring the prism, and the second detection unit includes a prism provided at the second point and a second. Claim 1 is composed of a total station, and the first and second total stations measure the heights of the first and second prisms, and detect ΔA and ΔB based on the measurement results. Asphalt finisher described in. One of the first detection unit and the second detection unit has an inclination sensor for measuring the inclination of the leveling arm, and the inclination angle detected by the inclination sensor, the distance between the first point and the second point. The asphalt finisher according to claim 1, wherein the height is detected based on the height detected by either the first detection unit or the second detection unit. The asphalt finisher according to claim 6, wherein either the first detection unit or the second detection unit is an ultrasonic sensor. Either the first detection unit or the second detection unit is composed of a receiver and a laser beam that is rotationally irradiated at a constant speed. The laser beam is composed of a plurality of fan beams and at least one fan. The asphalt finisher according to claim 6, wherein the beam is inclined at a known angle with respect to the horizontal plane, and the receiver detects the height based on the light receiving time difference when receiving the fan beam. The sixth aspect of claim 6 comprises a prism and a total station for tracking and measuring the prism, and the total station measures the height of the prism. The listed asphalt finisher. The control device has design data of the entire range of pavement construction as a pavement design line, and the height change amount ΔA regarding the design data of the first point detected by the first detection unit and the second detection unit detects the height change ΔA. The pivot cylinder is controlled so that the support shaft is displaced by − (ΔA + ΔB) based on the height change amount ΔB for the two design data, and the attack angle α on the bottom surface of the screed is maintained at a predetermined value. The asphalt finisher according to claim 1. The traveling body further includes a plurality of GNSS for acquiring geocentric coordinates, and the control device has three-dimensional actual measurement data and design data of the local board in the entire range of paving construction, and the geocentric of the construction position by GNSS. The asphalt finisher according to claim 1, wherein the coordinates are acquired and the ΔA and the ΔB are calculated by comparing the three-dimensional actual measurement data at the geocentric coordinates with the design data. A traveling body, a screed pulled by the traveling body, a leveling arm integrally provided with the screed and extending forward, and a leveling arm provided on the traveling body so as to be vertically displaceable, and a tip portion of the leveling arm is provided. An asphalt finisher including a support shaft connected to a traveling body, a pivot cylinder for moving the support shaft up and down, and a control device, which is in the vicinity of the support shaft of the leveling arm and with respect to the support shaft. The height of the known first point and the height of the second point located at a predetermined distance from the first point of the leveling arm are detected, respectively, and the height of the first point is obtained from the detected height and the pavement design line. A screed control method in which the pivot cylinder is controlled so as to detect the amount of change ΔA and the amount of change in height ΔB of the second point and displace the support shaft by − (ΔA + ΔB).

Images