JPH023842B2 - - Google Patents

Description

[Detailed description of the invention]

"Field of Industrial Application" The present invention relates to a method for measuring pavement thickness when paving a road using a leveling machine such as an asphalt finisher or base paper. ``Prior Art'' As is well known, in an asphalt finisher, the asphalt mixture (hereinafter referred to as composite material) in the hopper is fed to the rear spredding screw by a bar feeder while the vehicle is running. A screed is used to spread it evenly from side to side, and a screed suspended from the rear end of the leveling arm spreads it out evenly. By the way, when paving roads with a leveling machine such as the above-mentioned asphalt finisher, if the pavement thickness becomes thinner than the design value, the strength of the pavement becomes weaker, and conversely, if it becomes thicker than the design value, the strength of the pavement becomes weaker. There is no problem in terms of strength, but there is a problem in that the amount of composite material consumed increases and economic losses are incurred. Therefore, when paving roads, it is necessary to proceed with the work while checking from time to time whether the pavement thickness is as designed. However, in the past, this pavement thickness was checked by a worker different from the one operating the leveling machine inserting a gauge rod whose insertion distance was adjusted to the target pavement thickness into the constructed pavement. Was. For this reason, at least two workers are required for one leveling machine, which has been a major obstacle to promoting labor savings. In addition, there were problems in that not only the hard-constructed pavement was damaged, but also the thickness of the pavement could not be checked continuously, and this checking process itself required skill. Therefore, the present applicant, for example,
, we devised a leveling machine equipped with a pavement thickness measuring device that automatically measures pavement thickness continuously. The pavement thickness measuring device of this leveling machine consists of a vehicle body inclination angle detector that detects the longitudinal tilt angle of the vehicle body, and a vehicle height detector that detects the height of the reference point of the vehicle body from the road surface. , an arm inclination angle detector that detects the longitudinal inclination angle of the leveling arm, an arm height detector that detects the vertical distance of the swing center point of the leveling arm from the reference point, and a It consists of a pavement thickness calculation means that calculates pavement thickness based on data, and continuously detects variables related to the inclination angle and height of the traveling vehicle body and the inclination angle and height of the leveling arm, and uses the detected data. The pavement thickness is calculated by entering the following into the required calculation formula. "Problems to be Solved by the Invention" In the above pavement thickness measuring device, when the condition of the traveling vehicle body or leveling arm changes, the slope of the screed changes and the pavement thickness changes, and the calculated value of the pavement thickness changes accordingly. change. However, the measured values may fluctuate frequently due to disturbances caused by mechanical vibrations of the running vehicle or uneven ground, and in such cases, there is a problem in that it becomes difficult to manage the pavement thickness. Ta. The present invention was made in view of the above circumstances, and
An object of the present invention is to provide a method for measuring pavement thickness in a leveling machine that reduces variation in measured values and facilitates pavement thickness management. "Means for Solving the Problems" In order to achieve the above object, the pavement thickness measuring method of the present invention includes a leveling arm attached to a traveling vehicle body so as to be swingable within a vertical plane along the longitudinal direction of the traveling vehicle body. In addition, in a leveling machine in which the leveling arm is equipped with a screed for leveling the asphalt mixture on the road surface, a reference value for pavement thickness is set with the initial state of the leveling machine as the initial state. Detect the height of the center of swing of the leveling arm, the inclination state of the leveling arm in the longitudinal direction, etc., calculate the pavement thickness based on these detected values, and add the calculated value to the reference value by a predetermined amount. If the calculated value is within the standard range, the calculated value is considered to be the measured value of pavement thickness, and if the calculated value is not within the standard range, the standard value itself is considered to be the measured value of pavement thickness. The average value of the measured values in a time interval is used as the reference value in the next time interval. "Operation" In the method of the present invention, the height of the center of swing of the leveling arm and the inclination state of the leveling arm in the longitudinal direction are detected, the pavement thickness is calculated based on the detected values, and the calculated value is used as the pavement thickness. The measured value is
If the measured value is not within a reference range obtained by adding or subtracting a predetermined amount from the reference value, it is cut off as disturbance data and the reference value is used as the measured value, thereby reducing fluctuations in the measured value. In addition, the set value is used as the reference value in the initial state, but after the initial state, this is updated so that the average value of the measured values in a predetermined time interval becomes the reference value in the next time interval. Even if the reference value is regarded as the measured value, no large error will occur. “Example” An example of the present invention will be described below. First,
An example of a pavement thickness measuring device for carrying out the method of the present invention will be described with reference to FIGS. 1 to 11. FIGS. 2 and 3 show the entire asphalt finisher, in which a pair of left and right link members 2, 2 are attached to both sides of a traveling vehicle body 1 with one end rotatably supported, A pair of left and right leveling arms 4, 4 having a screed 3 suspended at their rear ends are attached to the other ends of these link members 2, 2, with their front ends rotatably supported by pivots 5, 5. These leveling arms 4,
4 has a structure that can freely swing up and down within a vertical plane along the longitudinal direction of the traveling vehicle body 1. Further, the ends of rods of a pair of left and right leveling cylinders 6, 6, which are hydraulic cylinders whose base ends are rotatably connected to the frame 1a of the traveling vehicle body 1, are rotatably connected to the link members 2, 2. By expanding and contracting these leveling cylinders 6, 6 and rotating the link members 2, 2, the pivots 5, 5, which are the pivot points of the leveling arms 4, 4, can be rotated. It can be moved up and down from the reference position. The asphalt finisher is equipped with a pavement thickness measuring device for automatically measuring the pavement thickness D. As shown in Fig. 1, the above-mentioned pavement thickness measuring device has the following features:
Detection means 11 consisting of a vehicle body tilt angle detector 7, a pair of left and right vehicle body height detectors 8, 8, arm tilt angle detectors 9, 9, and arm height detectors 10, 10;
a pavement thickness calculation section 12 that calculates a calculated value Dc of the pavement thickness D based on the signal from the detection means 11;
A reference value setting update section 13 that sets and updates the reference value Ds of and a determination section 14 for determining the measured value Dr of D. The vehicle body inclination angle detector 7 detects the inclination angle θ ₀ of the vehicle body 1 in the longitudinal direction with respect to a horizontal reference plane. , horizontal plate 16 in box 15
It is placed in a fixed state. Further, the vehicle body height detectors 8, 8 measure the height from the road surface of the left and right reference points S, S of the traveling vehicle body 1, which are at the same height as the reference positions of the pivot shafts 5, 5 of the leveling arms 4, 4. As shown in _FIGS . 6 to 8, bearings are mounted on boxes 17 _, 17 fixed to the frame 1a of the vehicle body 1.
Rotating shafts 19, 19 are rotatably mounted horizontally via 8, and arms 21, 21 whose upper ends are fixed to one ends of the rotating shafts 19, 19 and whose lower ends are provided with casters 20, 20, The rotating shaft 19,
It consists of potentiometers 23, 23 connected to the other end of 19 via bellows couplings 22, 22. The rotating shafts 19, 19 are the pivot shafts 5,
5, and its axis is at the reference point S,
When the casters 20, 20 are made to run on the road surface, the arms 21, 21 move up and down, the rotating shafts 19, 19 rotate, and the rotation angle is electrically controlled by the potentiometers 23, 23. The heights of the rotating shafts 19, 19 from the road surface, that is, the heights H ₀ , H ₀ of the reference points S, S of the traveling vehicle body 1 from the road surface are detected as signals. The arm inclination angle detectors 9, 9 detect the inclination angle θ ₁ of the leveling arms 4, 4 in the front-rear direction from the reference state, and the leveling arms 4, 4 are provided approximately at the upper center. The arm height detectors 10, 10 also include the leveling arms 4,
4 pivots 5, 5 and the reference points S, S of the traveling vehicle body 1
The vertical distance H ₁ , H ₁ between
It detects the vertical displacement from the reference state of 5.
As shown in FIGS. 9 and 10, mounting plates 25, 25 are attached to the handrail 24 on the step 1b of the vehicle body 1.
cylindrical linear detectors 26, 26 through
Attach vertically with the movable needle facing downward,
In addition, the movable needle tips of the linear detectors 26, 26 are connected to mounting seats 29, 29 at the front ends of the leveling arms 4, 4 via connection bars 27, 27 and connection fittings 28, 28. be. Then, when the pivot shafts 5, 5 of the leveling arms 4, 4 move up and down, the displacement of the up and down movements causes the connecting bars 27, 2
7. Linear detector 2 via connecting fittings 28, 28
6 and 26, and electric signals related to the vertical distances H ₁ and H ₁ can be obtained. On the other hand, the pavement thickness calculation section 12, reference value setting update section 13, and determination section 14 are operated by a microcomputer C.
The pavement thickness calculation unit 12
are each detected value θ ₀ detected at a predetermined time interval by the detection means 11 and converted from an analog signal to a digital signal by the A/D converter 30,
Substitute θ ₁ , H ₀ , and H ₁ into the relational expression Dc=H ₀ +H ₁ +Lsin(θ ₁ +θ ₂ −θ ₀ )−A to find the calculated values Dc and Dc of the left and right pavement thicknesses D and D. It is something. Here, L is the effective length of the leveling arms 4, 4, θ ₂ is the inclination angle of the leveling arms 4, 4 in the reference state, and A is the height of the screed 3, each of which is input as a constant value in advance. Further, the reference value setting update section 13 includes the determination section 1
4, the reference value Ds of the pavement thickness D used in step 4 is output to the determination unit 14. During the next fixed time _t1 after the elapse of _the fixed time to, the measured value Dr( 0) ( _n 〓 ⁱ⁼¹ Dr(0)i)/m is output as the reference value Ds(1) instead of the initial value Dr(0), and furthermore, the above fixed time t ₁
During the next fixed time t _{2 ,} the average value ( _n 〓 ⁱ⁼¹
Dr(1)i)/m is output as the reference value Ds(2) instead of the reference value Ds(1), and in this way, Ds(n) is sequentially updated for a certain period of time tn, and the determination unit 14 This is what is output to. Furthermore, the determination unit 14 compares the calculated value Dc of the pavement thickness D calculated by the pavement thickness calculation unit 12 with the reference value Ds from the reference value setting update unit 13 to obtain a measured value Dr, A predetermined amount α to the reference value Ds
If the calculated value Dc is within the standard range after adjusting or subtracting, that is, Ds−αDcDs+α,
While the calculated value Dc is output as is as the measured value Dr, if the calculated value Dc is not within the above reference range, that is, Ds−α>Dc or Dc>Ds+α
In this case, the reference value Ds is used as the measured value Dr instead of the calculated value Dc.
This is what is output as. A display section 31 consisting of an LCD is connected to the determination section 14 via an I/O interface 32. In addition, 33 in the figure indicates the scale plates 34, 34 and the pointer 3.
5 and 35, 36 is a hopper, 37 is a perfeeder, and 38 is a spreading screw. However, when asphalt pavement is performed on a road using an asphalt finisher, as in the conventional method,
While the traveling vehicle body 1 is running at a constant speed, the mixed material put into the hopper 36 is sent to the spredding screw 38 by the perfeeder 37 and supplied to the front part of the screed 3. Then, the screed 3 is pushed upward by the resistance of this composite material, and the composite material is compressed by the weight of the screed 3 itself, but when the resistance and the weight of the screed 3 are balanced, the leveling arm 4, 4 is determined, the attack angle β of the screed 3 is determined, and the composite material is laid on the road with the required pavement thickness D. Here, the worker must proceed with the work while checking whether or not the pavement thickness D is at the set value, but in the method of the present invention, the pavement thickness D is measured using the pavement thickness measuring device having the above configuration. are detected continuously. That is, the vehicle body inclination angle detector 7 detects the inclination angle θ ₀ of the traveling vehicle body 1, and the vehicle body height detectors 8, 8 detect the tilt angle θ 0 of the traveling vehicle body 1.
The heights H ₀ and H ₀ of the reference points S and S from the road surface are detected at predetermined time intervals, respectively, and the arm inclination angle detectors 9 detect the inclination angle of the leveling arms 4 from the reference state. θ ₁ , arm height detector 10,
10 samples and detects the vertical distances H ₁ and H ₁ between the pivots 5 and 5 of the leveling arms 4 and 4 and the reference points S and S at predetermined minute time intervals (for example, 50 msec). Then, these detected values θ ₀ , θ ₁ , H ₀ , H ₁ are sent to the pavement thickness calculating section 12 as digital signals via the A/D converter 30, and the left and right coating thicknesses D are calculated based on the above-mentioned formula. , the calculated value of D
Dc and Dc are required. Next, each pavement thickness D
The calculated value Dc is sent to the determination section 14, and it is determined whether or not it is within the reference range centered on the reference value Ds from the reference value setting update section 13, as shown in FIG. , that is, Ds−αDc
In the case of Ds+α, the calculated value Dc is outputted to the display unit 31 as the measured value Dr, and when it is not within the reference range, that is, if Ds−α>Dc or Dc>Ds+α, the reference value Ds is outputted as the measured value Dr to the display unit 31. will be displayed. Therefore, the worker can proceed with the paving work while checking this measured value Dr, and can avoid the conventional inefficient work of measuring the pavement thickness D by sticking a gauge rod into the constructed pavement. This makes it possible to speed up paving work and save labor. Here, if there is a disturbance due to mechanical vibrations of the traveling vehicle body 1 or the like or disturbances due to unevenness of the ground, the calculated value Dc of the pavement thickness D calculated by the pavement thickness calculating section 12 will frequently fluctuate. However, with the above method, the calculated value
When Dc exceeds the reference range due to disturbance, the reference value Ds is used as the measured value Dr, and the measured value Dr becomes a stable value. Moreover, although the initial value Ds (0) of the above reference value Ds is determined by the setting, after a certain period of time has passed, the reference value Ds becomes the value measured continuously during that certain period of time.
Since the averaged value of Dr is used as the reference value Ds for the next certain period of time, it is possible to obtain an extremely reliable measured value Dr. Therefore, it becomes easy to manage the pavement thickness, and it is possible to improve the efficiency of paving work. "Effects of the Invention" As explained above, the pavement thickness measuring method of the present invention detects the height of the swinging center point of the leveling arm, the state of inclination in the longitudinal direction, etc., and calculates the pavement thickness based on the detected values. At the same time, compare the calculated value with the reference range and examine it. If the calculated value shows an abnormal value due to disturbance etc., use the reference value instead to suppress the dispersion of the measured value due to disturbance etc. By using the average value of the prescribed values as the reference value, the measurement accuracy is maintained at a high level, making it possible to obtain accurate pavement thickness data with little variation, making it easy to manage pavement thickness. As a result, paving work can be done more quickly.

[Brief explanation of drawings]

The drawings are for explaining one embodiment of the present invention, and Fig. 1 is a block diagram of a pavement thickness measuring device, and Fig. 2 is a block diagram of a pavement thickness measuring device.
The figure is a plan view of the asphalt finisher, Figure 3 is a side view of the same, Figure 4 is a side view of the vehicle body inclination angle detector, Figure 5 is a view taken in the - arrow direction of Figure 4, and Figure 6 is the height of the vehicle body. A plan view of the detector, Fig. 7 is a side view of the same, Fig. 8
The figure is a sectional view taken in the direction of the - arrow in Fig. 7, Fig. 9 is a side view of the arm height detector, and Fig. 10 is a - arrow sectional view in Fig. 9.
Fig. 11 is a side view of the main parts for explaining the calculation formula for pavement thickness, Fig. 12 is a flowchart of the judgment section and reference value setting update section, and Fig. 13 is an explanatory diagram of the same. . 11...Detection means, 12...Pavement thickness calculation section, 1
3... Reference value setting update section, 14... Judgment section.

Claims (1)

[Claims] 1 A leveling arm is attached to the traveling vehicle body so that it can swing freely within a vertical plane along the longitudinal direction of the traveling vehicle body,
In addition, in a leveling machine in which the leveling arm is equipped with a screed for leveling the asphalt mixture on the road surface, a reference value for pavement thickness is set with the initial state of the leveling machine as the initial state. Detect the height of the center of swing of the leveling arm, the inclination state of the leveling arm in the longitudinal direction, etc., calculate the pavement thickness based on these detected values, and add the calculated value to the reference value by a predetermined amount. If the calculated value is within the standard range, the calculated value is considered to be the measured value of pavement thickness, and if the calculated value is not within the standard range, the standard value itself is considered to be the measured value of pavement thickness. A method for measuring pavement thickness in a leveling machine, characterized in that the average value of the measured values in a time interval is used as the reference value in the next time interval.