JPH026087Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to an automatic steering device for paving vehicles such as asphalt finishers and concrete finishers.

``Prior Art'' As is well known, some paving vehicles, such as asphalt finishers, use a bar feeder to spread the asphalt mixture in the hopper onto the rear spreading screen while the vehicle is running at a predetermined speed. There is a system in which the concrete is spread evenly to the left and right using a spreading screw, and then spread flat on the road surface using a screed.

Conventionally, such work vehicles have been operated by two workers, an operator who drives the machine and a screed man who operates the screed, but there have been complaints that it is labor-intensive and uneconomical. .

Therefore, as a means to resolve such dissatisfaction, the present applicant has proposed Japanese Patent Application No. 59-218136, etc., and has achieved a temporary solution by attempting to automate paving vehicles. This consists of a steering wheel, an actuator that changes the direction of the steering wheel, a sensor that detects the position based on the driving reference line laid along the road surface to be paved, and the information sent from this sensor. The apparatus includes a command device that receives the detection signal and issues a correction command signal to operate the actuator.

``Problems that the invention aims to solve'' However, in these examples, when a paving work vehicle is actually driven, it is difficult to pave the road surface while reliably controlling the vehicle body along the road surface to be paved. It was difficult to do so.

Therefore, as a result of extensive research and experiments to address these problems, the applicant has discovered that the object to be measured (driving reference line) detected by the sensor becomes dirty due to weather and work conditions. This led to the idea that it is difficult to extract signals without disturbance. In particular, when using an optical sensor as a sensor for a running vehicle, it is desirable that the object to be measured be optically uniform, but there may be construction materials such as asphalt on the surface of the object to be measured, such as the driving reference line. When doing so, it was discovered that it was difficult to extract a continuous disturbance-free signal.

In addition, when a reference object such as wood used as formwork for the road surface during paving or a curb on the side of the construction road surface is used as the object to be measured, optical means alone cannot measure this as the object to be measured. Difficult to distinguish from others
It was also discovered that it was said to be unusable.

It should be noted that, in order to solve such problems, installing a new object to be measured requires a lot of manpower, resulting in a decrease in work efficiency.

The purpose of this invention is to eliminate such conventional problems, detect stable signals, improve control reliability, and improve work efficiency and reduce costs with a simple structure. An object of the present invention is to provide an automatic steering device for a paving work vehicle that can achieve the following objectives.

``Means for Solving Problems'' In order to achieve the above-mentioned purpose, the present invention aims to move the vehicle body along a reference object such as a curb laid on the side of the construction road surface or a formwork used for construction. A paving vehicle that runs a road surface and spreads asphalt mixture or concrete on a road surface. and a command device that receives a detection signal sent from the position detection device and issues a correction command signal to operate the actuator, and the position detection device includes:
a guide member placed on the reference object and movable along its length; a connecting means for swingably connecting the guide member to the traveling vehicle body; The detection means detects the movement of the member and generates a detection signal.

"Function" With the above configuration, when the paving vehicle is running, the guide member moves over the reference object via the coupling means as the vehicle moves, and the movement of the guide member is detected by the detection means. Then, a detection signal is issued to a command device, which controls the operation of the actuator of the steering wheel.

``Embodiment'' An embodiment of the present invention will be described below with reference to the drawings, taking an asphalt finisher as an example.

1 to 7 show an embodiment of the present invention, and in the figures, 1 is a running vehicle body of an asphalt finisher. This running vehicle body 1 has a front part (first
A hopper 2 (on the left in the figure) is equipped with a hopper 2, and the bar feeder 3 sends the asphalt mixture to the rear, and a screw 4 spreads it on the road surface. The structure is such that compaction is performed using an adjustable screed 5.

Further, a position detection device 6, which will be described in detail next, is provided on the front right side of the traveling vehicle body 1, and a command device 7 is mounted in the center.

The position detection device 6 detects a reference object 8 such as a curb or formwork (formwork in the illustrated example) laid on the side of the construction road surface.
The device detects the position of the traveling vehicle body 1 based on the reference object, and includes a guide member 9 that is placed on the reference object and is movable along its length, and a guide member 9 that is swingable relative to the traveling vehicle body. Connecting means 10 to connect
and a detection means 12 located above the guide member 9, which detects the movement of the guide member 9 and issues a detection signal.

Here, as shown in FIG.
The guide member 9 has a front portion 9a (left side in FIG. 5) in the direction of movement, and the guide member 9 is formed to expand outward toward the tip. on the other hand,
On the upper surface 9b of this guide member 9, there is a reflecting plate 13 made of a stainless steel plate, a white painted plate (wood, metal), a white tape (paper, vinyl), etc., and a connecting arm 11 of the connecting means 10. A bracket 14 for joining is attached.

The connecting means 10 includes a support arm 10a which is fixed to one side of the traveling vehicle body 1 so as to protrude outward (rightward in FIG. 2), and a guide member 9 which can be swung vertically and horizontally with respect to the support arm 10a. The support arm 10a is provided with a hook 15 at its tip, as shown in FIG.
A ring 11a at the tip of the ring 11a is fitted into the ring 11a.

Further, as shown in FIG. 6, a universal joint 16 is provided at the other end of the connecting arm 11, and this universal joint is fixed to the bracket 14 of the guide member 9 via a nut 17.

As shown in FIGS. 3 and 4, the detection means 12 is composed of three optical sensors 18, 19, and 20 consisting of a light emitter and a light receiver, and the central optical sensor 19 detects the reflector 13 and issues a signal to notify that the traveling vehicle body 1 is in the correct position, and the left optical sensor 1
8 detects the reflector 13 and issues a signal in the same manner as above to notify that the vehicle body 1 is moving to the right;
Further, the right optical sensor 20 detects the reflection plate 13 and issues a signal to notify that the vehicle body 1 is moving to the left.

In the above, the center optical sensor 19 is fixed to a holder 23 that is attached to the support member 21 so as to be movable back and forth (up and down in FIG. It is fixed to holders 22 and 24 which are movably attached to the holders 22 and 24.

Further, the support member 21 includes a cylindrical movable beam 25
The end member 27 inserted into the tip of the support member 21 and fixed with a tightening bolt 26 moves up and down by tightening the bolt 29 inserted into the elongated hole 28 of the support member 21 and screwed into the end member 27. Possibly fixed.

Furthermore, the movable beam 25 is movably fitted into a fixed beam 30 which is fixed to the front right side of the traveling vehicle body 1 and protrudes rightward.
It is fixed by. Therefore, in the above configuration, by loosening the tightening bolt 31 and expanding and contracting the movable beam 25 with respect to the fixed beam 30, the distance of the detection means 12 from the traveling vehicle body 1 can be made to correspond correctly to the working conditions at the site. The height of the detection means 12 can be adjusted by loosening the bolt 29, and the relationship between the optical sensors 18, 19, 20 can be adjusted by moving the holders 22, 23, 24 back and forth and left and right with respect to the support member 21. Can be fine-tuned.

The command device 7 receives the detection signals emitted from the optical sensors 18, 19, and 20, and as shown in FIG. The direction of the steering wheel 32 is changed by controlling the operation of the actuator 34. That is, as shown in FIG. 10, the command device 7 consists of a microcomputer, and its CPU (central processing unit) 7
a is connected to the detection means 12 of the position detection device 6 and the rotary encoder 40 via one I/O interface 7b, and the hydraulic pressure of the actuator 34 is connected via the other I/O interface 7c. The electromagnetic switching valve 41 incorporated in the circuit and the traveling vehicle body 1 of the asphalt finisher
An electromagnetic switching valve 43 is incorporated into the circuit of the main clutch hydraulic cylinder 42 that operates the running/stopping of the main clutch.
are connected to each other.

Then, in response to the detection signals sent from the position detection device 6 and the rotary encoder 40, a command is issued to the electromagnetic switching valves 41 and 43, and if the traveling direction of the traveling vehicle body 1 deviates from the structure 8, this is corrected. move the actuator 34 so that
The main clutch hydraulic cylinder 42 is operated to stop traveling when necessary.

The control mode of the actuator 34 by the command device 7 is as shown in FIG.

That is, to explain the outline of this, the central optical sensor 19 is positioned directly above the reflection plate 13 of the guide member 9 placed on the reference object 8 and starts. No correction orders will be issued at this time. After the correction interval time T has elapsed, the left optical sensor 18
Since the detection signal of the reflection plate 13 is outputted from the control device 7, the command device 7 sends a modification command to the actuator 34 so that the direction change of the unit modification amount (α amount) is performed to the left. Furthermore, since this state continues even after the elapse of time T, and the command signal for correction to the normal state has already been maintained, no additional correction command is issued from the command device 7. After that, a detection signal is emitted from the optical sensor 19 in the center, and the traveling vehicle body 1 moves to the left with respect to the structure 8 and returns to the normal traveling state. A correction command is issued to 34 to restore the normal running operation state.

In the above case, the position comparison and correction amount are performed by CPU7
For example, a is the optical sensor 18 [1], the optical sensor 1
9 as [2] and optical sensor 20 as [3], and store the position data in the memory.The previous detection signal is determined from the value of the position data of the optical sensor that issued the current detection signal. Perform calculation processing to subtract the value of the position data of the optical sensor that was output, and if the answer is +1, move α to the right, if the answer is -1, move α to the left,
Also, in the case of +2, a correction command is issued such as 2α to the right, and in the case of -2, 2α to the left.

In the case of the one in Fig. 8, if the state in which no detection signal is received from any optical sensor continues for 2T hours, a correction command of ±2α is issued, and if it continues for 3T, the I/O interface is sent from the CPU 7a. The main clutch hydraulic cylinder 42 is operated via the ace 7c, the main clutch is disengaged, and the movement of the asphalt finisher is stopped.

45 is the detection means 1 of the position detection device 6.
A cover 46 surrounding the screw 2 is an auxiliary screw attached to the screw 4.

Next, the operation of the paving vehicle constructed as described above will be explained with reference to FIG.

When paving is to be carried out using an asphalt finisher equipped with the automatic steering device of this embodiment, preparatory work is carried out according to the following procedure.

First, the traveling vehicle body 1 is aligned with a reference object 8 such as a formwork laid on the road surface, a guide member 9 is placed on the reference object 8, and this guide member 9 is placed on the front part of the traveling vehicle body 1. Hook 1 of fixed support arm 10a
5 via a connecting arm 11.

Next, by loosening the tightening bolt 31 of the movable beam 25 and expanding and contracting the movable beam 25 with respect to the fixed beam 30, the separation distance of the detection means 12 is adjusted, and the detection means 12 is positioned directly above the guide member 9.

At this time, loosen the bolt 29 and remove the detection means 1.
2, and move the holders 22, 23, 24 back and forth and left and right with respect to the support member 21, finely adjusting the relationship between the optical sensors 18, 19, 20, and adjusting the height of the central optical sensor 19. Install it so that a detection signal is output.

When starting control, as shown in Figure 9, the command device 7 confirms the detection signal from the optical sensor, reads the position of the optical sensor that is emitting the detection signal, and turns on the automatic steering switch. , OFF is confirmed.

If this automatic steering switch is turned on, it is immediately checked to see if it is an initial start, and if it is an initial start, it is checked to see if work equipment other than the travel system is in a working position. . In the above, if the automatic steering switch is turned off, the presence or absence of a travel stop output is asked.

Furthermore, if the starting conditions are not met, the vehicle is returned to the starting position again. If the start conditions are met, or if the initial start is not made, it is checked whether the work vehicle is running or not based on the signal from the running speed encoder 40;
If the vehicle is running, the presence or absence of a signal from the optical sensor is determined. When the work vehicle is stopped in the above manner, it is returned to the starting position again. If there is a signal from the optical sensor, the count of the correction interval time T is cleared and it is checked whether the position data of the optical sensor is the same as the previous position data. If the position data is different, a correction command is sent to the actuator 34, and the traveling direction is corrected as shown in FIG. 8 described above. If the positions are the same, and after a correction command is issued, the data will be replaced and then returned to the starting position.

Further, if there is no data from the optical sensor, and a detection signal is output from the central optical sensor 19, the process returns to the start. Optical sensor 18, 20 at the end
is on the reflection plate 13 of the guide member 9 and is emitting a detection signal, a correction command is issued and correction is performed, time counting is started, and this state continues for a predetermined time T.

After that, it is confirmed whether or not the vehicle is uncontrollable, and if it is uncontrollable, an output to stop travel is sent to the main clutch electromagnetic switching valve 41, which activates the hydraulic cylinder 42 to release the main clutch of the travel drive system. If it is not out of control, it will be returned to its starting position.

When the traveling vehicle body 1 is moved forward, the guide member 9 moves over the reference object 8 via the support arm 10a and the connecting arm 11 as the traveling vehicle body 1 advances, and the movement of the guide member 9 is detected by the detection means. 1
2 will be detected. Therefore, the light emitted from the light projector of each optical sensor 18, 19, 20 of the detection means 12 is always reflected by the reflection plate 13 provided on the upper surface of the guide member 9 and detected by the light receiver. Therefore, detection signals without disturbance can be continuously extracted, and the reliability of control can be improved.

Also, during the above work, the guide member 9 is not placed on the rail dedicated to the guide member 9, but on a reference object (formwork in the illustrated example) 8 that is laid on the side of the construction road surface.
In this case, as shown in FIGS. 5 and 6, even if there is an obstacle such as a step or a pile 50 at the joint of the reference object 8, the guide member Since the portion 9a is formed to expand outward, the guide member 9 does not bump into these obstacles, and the paving work can proceed smoothly.

In the above, three optical sensors 18, 19,
Although the detection means 12 constituted by 20 has been described, the type and structure thereof may be arbitrary, and for example, it may be a contact type detection device. Further, even if optical sensors are used, the number of optical sensors used is not limited to three, and any number may be used, and the control form thereof is not limited to that shown in FIG.

Further, the connecting means 10 is not limited to the one described above, and may be configured to directly pull the guide member 9 to the traveling vehicle body 1 using, for example, a chain or the like.

In addition, in the embodiment described above, the reference object 8
Although the formwork laid on the side of the construction road surface has been described as follows, if this reference object 8 is a curb on the roadside, a guide member 9 corresponding to the shape of this curb is used, and its shape is the same as that in the embodiment. It is not limited to those of

"Effects of the Invention" As explained above, the present invention can produce the following excellent effects.

(A) The object to be measured (guide member) of the detection means that detects the position of the traveling vehicle body is pulled by the traveling vehicle body and measures against a reference object such as a formwork used for construction work or a curbstone laid on the roadside. Since it moves over the surface, there is no need to lay down the object to be measured in advance, allowing for efficient paving work and cost reduction. Moreover, this guide member moves as the traveling vehicle body travels,
Since the detection means is configured to detect the movement thereof, there is no risk of contamination with construction materials such as asphalt, and detection signals can be continuously extracted without disturbance.

(B) Since the guide member is easy to replace, it is possible to select a detection means with the most suitable shape and reflection performance, and stable signal detection is possible.

(C) Applicability to automatic steering of paving work vehicles such as asphalt finishers and concrete finishers can be improved, and reliability of control can be improved.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is a side view of an asphalt finish equipped with the automatic steering system of the present invention, Fig. 2 is a plan view thereof, and Fig. 3 shows the main features of the present invention. 4 is a view along the - line in FIG. 3, FIG. 5 is a plan view of the guide member, FIG. 6 is a side view thereof, and FIG. 7 is a schematic diagram of the hydraulic circuit of the actuator. , FIG. 8 is an explanatory diagram showing an example of a control form, FIG. 9 is an explanatory diagram showing an example of control of the command device, and FIG. 10 is a block diagram of the control system. 1... Traveling vehicle body, 6... Position detection device, 7...
Command device, 8...Reference object (formwork), 9...Guide member, 10...Support arm, 11...Connection arm, 12...Detection means, 13...Reflector, 16...
... Universal joint, 18, 19, 20 ... Optical sensor, 3
2... Steering wheel, 34... Actuator.

Claims (1)

[Scope of claim for utility model registration] (1) The vehicle body runs along a reference object such as a curb laid on the side of the construction road surface or a formwork used for construction, and the road surface is covered with asphalt mixture, concrete, etc. In the paving vehicle, the paving vehicle has a steering wheel;
An actuator that changes the direction of the steering wheel, a position detection device that detects the position based on the reference object, and a correction command signal that is sent to the actuator in response to a detection signal sent from the position detection device. and a command device for operating the position detection device, and the position detection device includes a guide member that is placed on the reference object and is movable along the length thereof, and a guide member that is swingable relative to the road surface vehicle body. an automatic steering device for a paving vehicle, characterized in that it is comprised of a connecting means connected to the guide member, and a detecting means located above the guide member to detect movement of the guide member and issue a detection signal. . (2) The detection means includes an optical sensor that detects a reflective plate provided on the upper surface of the guide member and emits a center position detection signal, an optical sensor that detects the reflective plate and emits a right position detection signal, and a reflective plate that detects the reflective plate and emits a right position detection signal. An automatic steering system for a paving vehicle according to claim 1, characterized in that it comprises an optical sensor that detects the left position and issues a left position detection signal.