JPH11350418A - Screed device for road paving vehicle such as asphalt finisher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To steplessly change a paving width up to above twice as much as a main screed in a screed device attached to a road paving vehicle such as an asphalt finisher. SOLUTION: A first telescopic screed 24 and a second telescopic screed 25 about the same in width as a main screed 23 are provided side by side in the rear in the advancing direction of the main screed 23, and support arms 26, 26 and 21, 27 are protrusively provided backward on both the upper outsides of the main screed 23 to support the first and the second telescopic screed 24, 25 so as to be laterally movable on each road surface. The first and the second cylinder 28, 29 are set mutually opposite in the upper part of the main screed 23, and each of their cylinder rods 28a, 29a is protruded through the holes of the support arms 26, 27 toward the outsides of the road surface width, and severally fixed to the upper left end face 30 of the first telescopic screed 24 and the upper right end face 31 of the second telescopic screed 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road paving vehicle such as an asphalt finisher for paving a road surface by spreading an asphalt mixture with a screed, and more particularly, to increasing a width of a main screed to about three times. The present invention relates to a screed device for a road paving vehicle such as an asphalt finisher having an expanding telescopic screed.

[0002]

2. Description of the Related Art In general, an asphalt finisher of this type sends out an asphalt mixture (hereinafter referred to as "mixture") from a hopper provided at a front portion of the fuselage to a rear surface of the fuselage, and removes the mixture that has dropped onto a road surface from a rear portion of the fuselage. The left and right sides are evenly spread by a screw spreader arranged rearward, and the mixture is spread to a predetermined width and thickness by a screed device behind the screw spreader.

FIG. 4 shows an example of a screed device 2 mounted on an asphalt finisher 1. As shown in FIG. 1, a conventional screed device 2 is provided with a main screed 3 and a rear portion of the main screed 3. And two types of screeds. The telescopic screeds 4 are disposed one by one on the left and right sides with a width approximately half of that of the main screed 3, and these telescopic screeds 4, 4 are moved outward by a feeding device (not shown) such as a cylinder or a screw rod in the direction of the road surface width. And by moving in opposite directions, the spreading width can be expanded to approximately twice the main screed 3. still,
Reference numeral 5 denotes a hopper for storing the mixture supplied from a truck or the like, reference numeral 6 denotes a conveyor feeder for taking out the mixture from the hopper 5 and dropping the mixture onto a rear road surface, and reference numeral 7 designates the left and right uniformity of the mixture dropped on the road surface. A screw spreader 8 for diffusing is a screed arm for pulling the main screed 3.

FIG. 5 shows the leveling angle (attack angle) of the screed device 2 with respect to the pavement surface 9 and the position of the rear end of the lower surface of each screed, including the amount of mixture held during construction. Due to various factors, the screed arm 8 moves up and down to determine the spreading angle. Depending on the spread angle at that time, the height of the rear end of the lower surface of the main screed 3 and the height of the rear end of the lower surface of the telescopic screed 4 may not coincide with each other. This causes streaks on the pavement surface 9. In order to prevent this, the telescopic screed 4 is moved up or down with respect to the main screed 3, and the step between the main screed 3 and the telescopic screed 4 is adjusted according to the change in the spread level angle. The lower rear end of the main screed 3 and the lower rear end of the telescopic screed 4 are adjusted to the same height from the existing roadbed 10, respectively.

[0005] Here, if the entire width of the screed device 2 is increased and the range in which the screed device 2 is spread at the same time is expanded, the work of spreading the mixture can be completed in a short period of time. However, the minimum width (approximately the same as the main screed width L) of the screed device 2 for loading and unloading by truck is limited to less than the inner width of the truck bed, and in the configuration shown in FIG. Is less than twice the main screed width L even at the maximum width Lmax.

For this reason, when leveling more than twice the main screed width L is performed, as shown in FIG. 6 (A), the expansion which expands and contracts behind a telescopic screed 4 by a cylinder (not shown) or the like. The screed 11 is provided or, as shown in FIG. 6B, the extended screeds 11, 11 are attached to the outer ends of the telescopic screeds 4, 4 via hinges or bolts (both not shown).

Alternatively, as shown in FIG. 7, a telescopic screed having substantially the same width as the main screed 3 is provided before and after the main screed 3.
12 and 12 are arranged one by one. Then, the front and rear telescopic screeds 12, 12 are moved by a feeding device (not shown) such as a cylinder in the outer direction of the road surface width and in the opposite direction to each other, so that the spread area of the mixture is reduced to approximately the main screed width. It is possible to expand three times.

Also, as in the screed device described in Japanese Patent Application Laid-Open No. 7-102521, first and second telescopic screeds are disposed behind the main screed in the traveling direction, and the first telescopic screed at the front is mainly provided. A structure is also known which is supported by a screed and supports a rear second telescopic screed by a front first telescopic screed.

[0009]

However, when the extended screeds 11, 11 shown in FIG. 6 (A) are moved outwardly of the road surface width, as shown in FIG. As the height adjustment points further increase,
A considerable amount of time and labor is required for adjusting the level of each screed, and a high level of skill is required. In the case of retrofitting the expansion screeds 11 and 11 shown in FIG. 6B, the expansion screed 10 is heavy and cannot be rotated by itself for deployment or folding. I need. Therefore, the work of attaching and detaching the extended screeds 11 and 11 becomes extremely complicated.

Further, in either of the configurations shown in FIGS. 6A and 6B, since the expansion screed 4 is configured to support the expansion screed 11, the expansion screed 4 is moved by the weight of the expansion screed 11. It becomes easy to hang outside the width. In order to prevent this, the expansion screed 11 must be small and simple. Therefore, it is difficult to obtain the same finished surface with each screed.

On the other hand, as described above, the spread angle of the screed device with respect to the pavement surface varies depending on various factors including the amount of mixture held therein, but the change in the amount of mixture held before the main screed. Most affected. In the screed device shown in FIG. 7, when the telescopic screed disposed on the front side of the main screed is moved, the amount of the mixture held before the main screed changes, whereby the lower rear end of the main screed and the telescopic screed are moved. There is a problem that the height of the rear end of the lower surface cannot be set correctly.

On the other hand, in the screed device described in Japanese Patent Application Laid-Open No. 7-102521, the height of the lower end of the lower surface of the second telescopic screed provided at the tail is lower than the lower end of the lower surface of the first telescopic screed provided at the front. There is a defect that it takes time to adjust the level difference of each screed because the error is accumulated in the height error. Also,
Since the first telescopic screed is provided behind the main screed and the second telescopic screed is provided behind the first telescopic screed, the cylinder for expanding and contracting the first telescopic screed has extremely high strength and capacity. It is required and causes cost increase.

Therefore, in the screed device mounted on the asphalt finisher, when the telescopic screed is stored, the width of the screed is limited to about the screed width of the main screed, and the pavement width is reduced to approximately twice the width of the main screed by a simple operation. A technical problem to be solved arises in order to be able to change in stages, and the first object of the present invention is to solve this problem.

Further, according to the present invention, the rear end of the lower surface of the main screed and the rear end of the lower surface of the telescopic screed can be easily and quickly adjusted to the same height from the existing roadbed in accordance with the change in the amount of mixture held therein, and It is a second object of the present invention to be able to maintain a constant thickness.

[0015]

SUMMARY OF THE INVENTION The present invention has been proposed to achieve the first object, and has a telescopic screed having a width substantially equal to the screed width of the main screed. A pair of front and rear parallel to the main screed are arranged side by side, and a supporting arm is projected toward the rear on both outer sides of the upper part of the main screed, and the pair of telescopic screeds are movable by the supporting arm in a road surface width direction. Support, and
Asphalt in which a pair of cylinders are provided opposite to each other on the upper part of the main screed so that the pair of telescopic screeds can be moved from the rear position of the main screed to the outer side of the road surface width and to the opposite sides from each other. A screed device for a road paving vehicle such as a finisher is provided.

Further, the present invention has been proposed to achieve the second object, and the pair of telescopic screeds comprises an upper screed and a lower screed,
The upper screed is supported by the support arms of the main screed so as to be movable along the width direction of the road surface, while the lower screed is supported by the lower side of the upper screed so as to be vertically movable via lifting means. By operating the means, the screed of a road-paved vehicle such as an asphalt finisher configured such that the height of the lower end of the lower surface of each lower screed can be adjusted according to the height from the existing roadbed to the lower end of the lower surface of the main screed. Is provided.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS. The same components as those in the related art are denoted by the same reference numerals, and description thereof will be omitted. The screed device 22 of the asphalt finisher 21 of the present invention includes a first telescopic screed 24 having substantially the same width as the screed width of the main screed 23, in the traveling direction of the main screed 23 on which the mixture is spread and paved. And a pair of second telescopic screeds 25 are arranged in front and rear in parallel with the main screed 23.

A pair of support arms 26, 26 and a pair of support arms 27, 27 are respectively provided on both upper outer sides of the main screed 23 so as to project rearward, and one of the support arms 26, 26 supports the first telescopic screed 24. And the other support arm 27, 27 has the second telescopic screed 25
To support. Then, the first cylinder 28 and the second cylinder 29 are installed on the upper part of the main screed 23 in a substantially horizontal and left-right opposite direction, and the respective cylinder rods 28a, 29a are respectively inserted into holes (not shown) of the support arms 26, 27. From the outside of the road width. On the other hand, the upper left end face 30 of the first telescopic screed 24 is extended forward, the tip end of the cylinder rod 28a of the first cylinder is fixed, and the upper right end face 31 of the second telescopic screed 25 is extended forward. The tip of the cylinder rod 29a of the second cylinder is fixed.

A hole (not shown) is formed in the rear portion of the support arms 26, 26 to fix a cylindrical guide 32 between the support arms 26, 26. The shaft 33 is slidably fitted, and both ends of the first guide shaft 33 are fixed to the upper left end face 30 and the upper right end face 34 of the first telescopic screed 24. Similarly, a hole (not shown) is formed in the rear part of the support arms 27, 27 to fix a cylindrical guide 35 between the support arms 27, 27. The shaft 36 is slidably fitted, and both ends of the second guide shaft 36 are fixed to the upper right end face 31 and the upper left end face 37 of the second telescopic screed 25.

As described above, the first guide shaft 33 and the second guide shaft 36 are respectively composed of the cylindrical guide 32 fixed between the support arms 26, 26 and the cylindrical guide 32 fixed between the support arms 27, 27. Since the first screed 24 and the second screed 25 are supported by being inserted into and supported by the shape guide 35, the vertical and vertical screed is restricted, and the same spread angle as the main screed 23 is maintained.

When the first cylinder 28 is extended, the upper left end surface 30 of the first telescopic screed 24 is pressed by the cylinder rod 28a, and the first telescopic screed 24 is integrated with the first guide shaft 33. The cylindrical guide 32 is slid outward of the road surface width. On the other hand, when the first cylinder 28 is contracted, the upper left end face 30 of the first telescopic screed 24 is pulled, and the first telescopic screed 24 is moved to the first guide shaft.
The cylindrical guide 32 is slid inwardly with the width of the road surface integrally with 33.

Similarly, when the second cylinder 29 is extended, the upper right end surface 31 of the second telescopic screed 25 is pressed by the cylinder rod 29a, and the second telescopic screed 25 is moved to the second telescopic screed 25.
The cylindrical guide 35 is slid integrally with the guide shaft 36 toward the outside of the road surface width. On the other hand, when the second cylinder 29 is contracted, the upper right end face 31 of the second telescopic screed 25 is pulled, and the second telescopic screed 25 is integrated with the second guide shaft 36 to move the cylindrical guide 35 on the road surface. Slide inward of the width.

Thus, the first telescopic screed 24 moves to the road surface width at the position behind the main screed 23 by the expansion and contraction of the first cylinder 28, and
The second telescopic screed 25 is located behind the main screed 23 and the first
Move to the road width at the position behind the telescopic screed 24. That is, the first telescopic screed 24 and the second telescopic screed 25
However, it is movable in parallel to the main screed 23 and in directions opposite to each other.

The maximum stroke of the first cylinder 28 and the second cylinder 29 when extended is the first telescopic screed.
24 to the left of the road width,
The telescoping screed 25 is moved to the right to the width of the road surface, so that the entire screed width of the screed device 22 is
It is set to be approximately three times the screed width of 23. Also, when the first cylinder 28 and the second cylinder 29 are at the minimum stroke, the first telescopic screed 24 and the second telescopic screed 25 are moved to positions where they overlap behind the main screed 23, respectively. Is set to be substantially the same as the screed width of the main screed 23.

For this reason, the screed width of the main screed 23 is set to be slightly shorter than the inner width of the truck bed, and the screed width of the first telescopic screed 24 and the second telescopic screed 25 is set to be the same as the screed width of the main screed 23. For example, the maximum spread width of the screed device 20 can be extended to approximately three times the screed width of the main screed 23. Of course, the expansion and contraction of the first cylinder 28 and the second cylinder 29 can be arbitrarily adjusted between the maximum stroke and the minimum stroke, and within this range, leveling corresponding to the road width is performed. be able to.

As described above, the spread angle of the first telescopic screed 24 and the second telescopic screed 25 is
Of the first telescopic screed 24
Even when the second telescopic screed 25 moves in the width direction of the road surface to change the spread width of the screed device 20, the spread angle of each screed does not change.

Here, the first telescopic screed 24 and the second telescopic screed 25 are respectively divided into upper screeds 24a, 25a and lower screeds 24b, 25b, and the guide shaft is provided above each of the upper screeds 24a, 25a. 33 and 36 are fixedly mounted and movably supported by support arms 26 and 27 of the main screed 23. On the other hand, the lower screeds 24b, 25b are connected to the upper screeds 24a, 25a via lifting cylinders 38, 38 as lifting means, respectively.
The lower screeds 24b and 25b are formed so as to be able to move up and down by the expansion and contraction operation of 38. The elevating means may be other than a cylinder, such as a screw rod.

When the mixture is spread on the road surface by the screed device 22, the screed arm 8 moves up and down due to various factors such as the amount of the mixture held, and the spread angle is reduced. Decided. At this time, the rear end of the lower surface of the main screed 23 and the first telescopic screed 24 and the second telescopic screed
If the height of the rear end of the lower surface of the lower screed 25 does not match, the lower screed 24
The b and 25b move up and down, and the step between the first telescopic screed 24 and the second telescopic screed 25 can be adjusted easily and quickly. Further, the asphalt finisher has been described as an example of a vehicle having a screed device, but the present invention can be applied to other road paving vehicles having a screed.

The present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0030]

As described in detail in the above embodiment, according to the first aspect of the present invention, the rearward and rearward expansion and contraction of the main screed having substantially the same width as the screed width of the main screed. A pair of screeds are arranged in front and rear in parallel with the main screed, and these telescopic screeds are configured to be moved to the outside of the road surface width and to the opposite sides by extending the cylinder. It can be expanded steplessly in a range up to about three times the width. In addition, the expansion and contraction of the pair of cylinders causes the telescopic screeds to move in opposite directions, so that the adjustment of the spread width of the screed device becomes extremely simple.

Further, since each telescopic screed is directly supported by the main screed by the support arm, even when the size of the telescopic screed is substantially equal to that of the main screed, the telescopic screed can be extended and contracted. High strength and capacity are not required for the cylinder. Accordingly, there is no difference in quality between the finishes by the respective screeds, and the cost can be reduced.

According to the second aspect of the present invention, the pair of telescopic screeds are composed of an upper screed and a lower screed, and the lower screed is moved up and down by the operation of a raising / lowering means, so that the rear end of the lower surface of the telescopic screed is formed. Height can be easily changed. Thus, the present invention has various effects, such as easy and quick adjustment of the level difference between the main screed and the telescopic screed, and improvement in working efficiency.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention and showing a screed device of an asphalt finisher in which telescopic screeds are stored.

FIG. 2 is a plan view illustrating the screed device of the asphalt finisher according to the embodiment of the present invention, in which an extendable screed is extended to a maximum width.

FIG. 3 shows an embodiment of the present invention, and is a view taken along line AA of FIG. 2;

FIG. 4 is a plan view showing a conventional screed device for an asphalt finisher.

FIG. 5 is a view taken along line BB of FIG. 4 for explaining a spread angle of the screed with respect to a pavement surface.

6A and 6B show a conventional screed device for an asphalt finisher, wherein FIG. 6A is a plan view showing an example in which an extended screed is provided behind an extendable screed, and FIG. The top view showing an example.

FIG. 7 is a plan view showing a screed device of an asphalt finisher in which telescopic screeds are arranged before and after a main screed.

FIG. 8 is a view taken along the line CC of FIG. 6 (A) for explaining the spread angle of the screed with respect to the pavement surface.

[Explanation of symbols]

 21 Asphalt finisher 22 Screed device 23 Main screed 24 First telescopic screed 24a Upper screed 24b Lower screed 25 Second telescopic screed 25a Upper screed 25b Lower screed 26 Support arm 27 Support arm 28 First cylinder 29 Second cylinder 38 Elevating cylinder

Claims (2)

[Claims] 1. A pair of telescopic screeds having substantially the same width as the screed width of the main screed are arranged in front and rear of the main screed rearward in the traveling direction of the main screed. , And the support arms support the pair of telescopic screeds so as to be movable in the width direction of the road surface, respectively. Further, a pair of cylinders are provided above the main screed in opposite directions to each other. A screed device for a road paved vehicle such as an asphalt finisher, wherein the pair of telescoping screeds are formed so as to be movable from a rear position of a main screed to an outside of a road surface width and to mutually opposite sides. 2. A pair of telescopic screeds comprising an upper screed and a lower screed, wherein the upper screed is supported by a support arm of the main screed so as to be movable along a road surface width direction, while the lower screed is respectively It is supported on the lower side of the upper screed via elevating means so as to be able to move up and down, and further, by operating the elevating means,
2. A screed device for a road-paved vehicle such as an asphalt finisher according to claim 1, wherein the height of the lower end of the lower surface of each lower screed can be adjusted according to the height from the existing roadbed to the rear end of the lower surface of the main screed.