JP7680974B2 - Concrete spreading device and concrete spreading method - Google Patents

Description

The present invention relates to a concrete spreading device and a concrete spreading method.

As described in JP 2014-62432 A (Patent Document 1), a concrete spreading device spreads concrete on the road surface in one step using a screed that extends in the left-right direction. Here, in the concrete spreading device described in Patent Document 1, the concrete is spread while operating a vibration device attached to the screed in order to increase the density of the concrete and improve the finish.

JP 2014-62432 A

Concrete is made by mixing the main component mortar (cement) and aggregate (stone, crushed stone, sand, etc.) in an appropriate amount. When this concrete is spread evenly on the road surface, the density of the concrete is improved by vibrating the screed. However, excessive vibration can cause the mortar components contained in the concrete to float to the surface in excess. If the concrete hardens in this state, a mortar layer will form on top of the aggregate, reducing its strength and potentially making it impossible to achieve the required strength.

The present invention aims to provide a concrete spreading device and a concrete spreading method that can prevent a decrease in the strength of the concrete spread on the road surface to be worked on.

The concrete leveling device includes a frame, a traveling device for traveling the frame, a plurality of screeds attached to the frame, a vibration device attached to the screed located at the front end in the traveling direction of the frame, and a finishing trowel attached to the rear of the plurality of screeds . Here, the plurality of screeds extend in the left-right direction with respect to the traveling direction of the frame, and are arranged at positions spaced apart in the traveling direction. The vibration device generates vibrations by an unbalanced weight rotated by an actuator. Furthermore, the finishing trowel extends parallel to the traveling direction of the frame, and reciprocates in the left-right direction with respect to the traveling direction of the frame.

In addition, in the concrete spreading method, the concrete spreading device configured as described above is used to move the frame using the traveling device, and concrete is spread and spread on the target road surface while operating the vibration device attached to the screed located at the forefront in the frame's traveling direction, and then the concrete is further spread and spread on the target road surface using another screed.

According to the present invention, when concrete is spread evenly over the road surface to be worked on, it is possible to prevent the mortar components contained in the concrete from floating to the surface, thereby preventing a decrease in the strength of the concrete.

FIG. 2 is a top view showing an example of a concrete spreading device. FIG. 2 is a front view showing an example of a concrete spreading device. FIG. 2 is a side view showing an example of a concrete spreading device. FIG. 2 is an enlarged view showing an example of a finishing trowel. FIG. 13 is an explanatory diagram of the finishing trowel in a folded state. FIG. 2 is an explanatory diagram of the finishing trowel in an unfolded state. 1 is a flowchart showing an example of a procedure for spreading concrete evenly. FIG. 4 is an explanatory diagram of a load acting on a finishing trowel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1 to 3 show an example of a concrete spreading device 100 that spreads concrete on a road surface to be worked on. The concrete spread on the road surface to be worked on by the concrete spreading device 100 is produced by appropriately mixing mortar (cement) as the main component, aggregate (stone, crushed stone, sand, etc.), water, and a small amount of air bubbles. The concrete may include heat-resistant concrete used on road surfaces exposed to high temperatures, such as runways.

The concrete leveling device 100 includes a frame 200, a traveling device 300 that runs the frame 200 in one direction (upward in the example shown in FIG. 1), and a first screed 400 and a second screed 500 attached to the frame 200. The first screed 400 and the second screed 500 extend in the left-right direction perpendicular to the running direction of the frame 200. The first screed 400 is disposed in front of the second screed 500 with respect to the running direction of the frame 200. In addition to the above configuration, the concrete leveling device 100 includes two vibration devices 600 attached to two separate positions on the first screed 400, which is located at the frontmost position in the running direction of the frame 200, of the first screed 400 and the second screed 500. Here, the number of vibration devices 600 attached to the first screed 400 is not limited to two, and can be any number that suits, for example, the vibration characteristics, the width of the road surface to be worked on, etc. (same below).

The concrete leveling device 100 described below has two screeds, the first screed 400 and the second screed 500, but may have three or more screeds. In this case, the vibration device 600 only needs to be attached to the screed that is located at the front end of the multiple screeds in the travel direction of the frame 200.

The frame 200 is made by appropriately joining multiple steel pipes, and includes a main frame 220 having a rectangular framework in a plan view, and a subframe 240 that is attached to the main frame 220 so that it can move up and down.

The main frame 220 is composed of four vertical members 222 whose material axes extend in the up-down direction, two first cross members 224 whose material axes extend in the left-right direction, two second cross members 226 whose material axes extend in the front-rear direction, two connecting supports 228 whose material axes extend in the front-rear direction, four leg members 230 connected to the lower ends of the vertical members 222, two connecting bars 232 whose material axes extend in the front-rear direction, and multiple (e.g., five) reinforcing members 234 whose material axes extend in the front-rear direction.

The vertical members 222 are made of two steel pipes whose length can be changed as desired, and are arranged at the four corners of the rectangular framework in plan view. The first horizontal member 224 is arranged to connect the two vertical members 222 arranged along the left-right direction at a predetermined location in the middle of the vertical members 222. The second horizontal member 226 is arranged to connect the two vertical members 222 arranged along the front-rear direction at a predetermined location in the middle of the vertical members 222. The connecting support 228 is arranged to connect the two vertical members 222 arranged along the front-rear direction at a predetermined location on the upper part of the vertical members 222. The leg member 230 is a box-shaped steel member that is rectangular in plan view with an open bottom, and is arranged at the lower end of the vertical member 222 with its long side extending in the front-rear direction. The connecting bar 232 is arranged to connect the two leg members 230 arranged along the front-rear direction at a predetermined location on the upper surface of the leg member 230. The reinforcing members 234 are arranged to connect two first cross members 224 arranged along the front-rear direction at a number of spaced apart locations on the first cross members 224.

The subframe 240 is configured to include a first member 242 whose material axis extends in the left-right direction, a second member 244 whose material axis extends in the left-right direction and whose total length is slightly longer than that of the first member 242, a plurality of cross members 246 whose material axis extends in the front-rear direction and connects the first member 242 and the second member 244 at a plurality of spaced apart locations, and a diagonal member 248 whose material axis extends diagonally and connects one end of the first member 242 to one end of the second member 244 protruding from the first member 242 in the left-right direction. Here, the first member 242 is disposed in front of the second member 244 in the running direction of the frame 200. In addition to the above configuration, the subframe 240 is provided with a rail member 250 that is integrated with the second member 244 located behind the running direction of the frame 200 and allows the finishing trowel 800 described later to slide in the left-right direction.

The subframe 240 is suspended elastically in a horizontal position relative to the mainframe 220 via two suspension devices 260 with built-in springs that are attached to two separate positions on the mainframe 220. Here, the suspension devices 260 are not limited to those that elastically suspend an object to be suspended using springs, and may be, for example, actuators consisting of electric motors and reducers, hydraulic cylinders, etc.

The traveling device 300 is configured to include a crawler 320 arranged in the internal space of the leg member 230 of the frame 200, a traveling actuator 340 that drives the crawler 320, and a reducer 360 that reduces the rotational speed of the output shaft of the traveling actuator 340. The traveling actuator 340 is attached to a predetermined location of the leg member 230 of the frame 200 via the reducer 360. Note that the traveling device 300 is not limited to the crawler 320, and well-known means such as iron wheels or rubber wheels can also be used.

The first screed 400 and the second screed 500 are each attached to the subframe 240 via two support devices 700 (some not shown) attached to two spaced apart positions on the subframe 240 so as to be slidable in the left-right direction. The first screed 400 and the second screed 500 are also reciprocated in the left-right direction in different phases from each other by a differential mechanism 720 attached to a predetermined location on the subframe 240, for example, the first member 242. Specifically, the differential mechanism 720 includes a differential actuator 722 such as an electric motor attached to the first member 242 of the subframe 240, a reducer 724 that reduces the rotational speed of the output shaft of the differential actuator 722, a disk member 726 fixed to the output shaft protruding from both sides of the reducer 724, and a connecting member 728 that connects the periphery of the disk member 726 to predetermined locations on the upper surfaces of the first screed 400 and the second screed 500 so that they can rotate relative to each other. Here, by appropriately differentiating the connection points of the connecting member 728 to each disk member 726, the first screed 400 and the second screed 500 reciprocate in the left-right direction with different phases from each other.

The vibration device 600 incorporates an unbalanced weight that is rotated by an actuator such as an electric motor, and generates vibrations of a predetermined frequency as the weight rotates. The vibration device 600 then transmits the generated vibrations to the concrete supplied to the road surface to be worked on via the first screed 400.

In addition to the frame 200, the traveling device 300, the first screed 400, the second screed 500 and the vibration device 600, the concrete spreading device 100 further includes a finishing trowel 800 that improves the flatness of the concrete spread on the road surface to be worked on by the first screed 400 and the second screed 500.

As shown in Figures 3 and 4, the finishing trowel 800 is attached to the rail member 250 of the subframe 240 so as to be slidable in the left-right direction, which is the extension direction of the rail member 250. Specifically, the finishing trowel 800 includes a support frame 810 having a rectangular shape in a plan view, a hanging frame 820 attached to the tip of the support frame 810 so as to be relatively rotatable, a trowel 830 attached to the lower end of the hanging frame 820, and a height adjustment mechanism 840 that adjusts the height of the trowel 830. Here, the support frame 810 and the hanging frame 820 are given as examples of mounting frames.

The base end of the support frame 810 is attached in a cantilevered state to the subframe 240 via a pair of upper and lower rollers 812 that sandwich and fix the upper and lower surfaces of the rail member 250. In addition, an actuator 814 such as an electric motor that generates a driving force for sliding the finishing trowel 800 in the left and right direction relative to the subframe 240 is attached to the upper surface of the base end of the support frame 810. A gear 816 that meshes with a rack 252 fixed to the upper surface of the subframe 240 via a reduction gear (not shown) is attached to the output shaft of the actuator 814. Therefore, when the actuator 814 is operated, the rotation speed of the output shaft is reduced by the reduction gear and transmitted to the gear 816, and the finishing trowel 800 can be slid to the left or right relative to the subframe 240 via the rack 252 that meshes with it.

The hanging frame 820 is attached to the tip of the support frame 810 so that it can rotate relatively around a rotation axis extending in the left-right direction.

The trowel 830 is composed of a trowel body 832 that finishes the concrete spread evenly on the road surface to be worked on, a pair of brackets 834 that extend upward from two spaced apart positions on the top surface of the trowel body 832, and a linear first member 836 and a linear second member 838 that are connected to the pair of brackets 834 so as to be rotatable relative to each other about a rotation axis that extends in the left-right direction. The tips of the first member 836 and the second member 838 are connected to be rotatable relative to each other about a rotation axis that extends in the left-right direction, and the connection point is connected to the lower end of the hanging frame 820. Therefore, the trowel body 832 of the finishing trowel 800 is fixed in a state in which it extends in the front-rear direction relative to the frame 200.

In addition, one of the pair of brackets 834 of the trowel 830, for example the lower end of the bracket 834 located at the front, is fixed in a state where it cannot move in the front-rear direction relative to the upper surface of the trowel body 832. On the other hand, the other of the pair of brackets 834 of the trowel 830, for example the lower end of the bracket 834 located at the rear, is fixed so as to be displaceable in the front-rear direction relative to the upper surface of the trowel body 832. Therefore, when the distance between the connection point of the trowel 830 to the hanging frame 820 and the bottom surface of the trowel body 832 changes, the bracket 834 located at the rear is displaced relative to the trowel body 832, changing the angle between the first member 836 and the second member 838, and the change in distance can be easily accommodated.

The height adjustment mechanism 840 includes a winch 842 attached to the tip of the support frame 810, a link member 844 bent in a "L-shape", a weight 846, and a roller 848. The bent portion of the link member 844 is attached to the support frame 810 via a mounting bracket 818 protruding upward from the upper surface near the tip of the support frame 810, with the bent portion positioned upward so as to be rotatable relative to the support frame 810 around a rotation axis extending in the left-right direction. A weight 846 is attached to one end of the link member 844, specifically, the end located at the front, so as to be rotatable relative to the rotation axis extending in the left-right direction. A roller 848 is attached to the other end of the link member 844, specifically, the other end located at the rear, so as to be rotatable around a rotation axis extending in the left-right direction. The free end of the wire 842A wound around the winch 842 is connected to a predetermined location of the iron body 832 via the roller 848 of the link member 844.

Therefore, by operating the winch 842 to change the length of the wire 842A, the relative position of the trowel body 832 with respect to the support frame 810 changes, and the height can be adjusted. At this time, as described above, the angle between the first member 836 and the second member 838 changes, making it easy to accommodate changes in the distance between the connection point of the trowel 830 with respect to the hanging frame 820 and the bottom surface of the trowel body 832.

A reciprocating mechanism 850 is attached to a predetermined location on the lower part of the support frame 810, which swings the hanging frame 820 back and forth relative to the tip of the support frame 810 and reciprocates the trowel 830 back and forth relative to the subframe 240. The reciprocating mechanism 850 includes an actuator 852 such as an electric motor that generates a rotational drive force, a reducer 854 that reduces the rotational speed of the output shaft of the actuator 852 and changes the direction of rotation by 90°, a disk member 856 fixed to the output shaft of the reducer 854, and a connecting rod 858 that connects a predetermined location on the periphery of the disk member 856 to the middle part of the hanging frame 820 so that they can rotate relative to each other around a rotation axis extending in the left-right direction.

Therefore, when the actuator 852 is operated, the rotational driving force of the rotating shaft is transmitted to the disk member 856 via the reducer 854, and the disk member 856 rotates around the rotating shaft extending in the left-right direction. When the disk member 856 rotates, the position of the connecting rod 858 in the front-rear direction changes, and the hanging frame 820 is swung in the front-rear direction over a predetermined angle relative to the tip of the support frame 810. As a result, the position of the trowel 830 relative to the support frame 810 changes in the front-rear direction, and the concrete can be finished within a range exceeding the entire length of the trowel body 832. At this time, even if the position of the trowel 830 relative to the support frame 810 changes in the front-rear direction, the connection angle of the first member 836 and the second member 838 relative to the lower end of the hanging frame 820 changes, so that the front-rear movement of the trowel body 832 can prevent the trowel body 832 from moving away from the surface of the concrete or being pressed against it more than necessary.

However, since the finishing trowel 800 extends vertically from the subframe 240 of the frame 200 toward the rear, this may cause problems, for example, when transporting the concrete leveling device 100. Therefore, as shown in FIG. 5, a known link mechanism or the like may be used to configure the finishing trowel 800 so that it can be folded parallel to the subframe 240. In this way, by folding the finishing trowel 800 when transporting the concrete leveling device 100, the length of the finishing trowel 800 protruding rearward from the subframe 240 becomes shorter, making it possible to load the concrete leveling device 100 on a truck, for example. When the transport of the concrete leveling device 100 is completed, the folded finishing trowel 800 can be unfolded as shown in FIG. 6.

In addition, a generator (not shown) that supplies drive current to the travel actuator 340 of the travel device 300, the vibration device 600, the differential actuator 722, and the actuators 814 and 852 of the finishing trowel 800, as well as a control panel (not shown) that controls the operation of these, are attached to a predetermined location of the frame 200. Then, by appropriately operating switches and the like attached to the control panel, the various actuators and the vibration device 600 are operated, and the function for achieving the required purpose is performed. The generator may be installed outside the concrete leveling device 100. Also, the various actuators and the vibration device 600 may be supplied with drive current from a commercial power source installed outside, not limited to a generator.

Next, an example of a method for spreading concrete on a road surface to be worked on using such a concrete spreading device 100 will be described. FIG. 7 shows a flowchart illustrating the steps for spreading concrete. Note that the steps shown in FIG. 7 are not limited to the order shown, and can be modified as appropriate to the extent that the concrete can be spread evenly.

In step 10 (abbreviated as "S10" in Figure 7, and so forth), the worker places the rebar continuously in the longitudinal direction on the road surface to be worked on.

In step 11, a worker or other person installs the concrete leveling device 100 at the end of the road surface to be worked on where the reinforcing bars are placed.

In step 12, a worker or the like begins to supply pre-hardened concrete, for example using a backhoe, onto the target road surface on which reinforcing bars have been placed and which is located in front of the concrete leveling device 100 in the direction of travel. At this time, the worker or the like may further spread the concrete supplied onto the target road surface.

In step 13, a worker or other person operates the concrete leveling device 100 and moves the concrete leveling device 100 while activating various actuators.

In this way, the concrete supplied to the road surface to be worked on is spread in the left-right direction by the first screed 400, which is located at the very front of the concrete spreading device 100 in the running direction, reciprocating in the left-right direction. Then, the first screed 400 passes over the surface of the concrete spread in this way, so that the spread thickness of the concrete can be brought closer to the target thickness to some extent. At this time, the first screed 400 is vibrated by the vibration device 600, so that the aggregate contained in the concrete can be firmly pressed, and the density of the concrete can be increased. In addition, since the first screed 400 does not complete the spreading of the concrete, there is no need to use strong vibrations from the vibration device 600, and it is possible to prevent mortar components from floating on the surface of the concrete and reducing its strength.

The concrete spread by the first screed 400 is further spread by the second screed 500, which is located behind it and moves back and forth in the left and right direction. At this time, both ends of the second screed 500 move while rubbing against the top surface of a formwork (not shown) that determines the concrete spreading height, so that the concrete spreading height can be brought even closer to the target height. In addition, since the second screed 500 is not vibrated by the vibration device 600, the concrete is not subjected to excessive vibrations, and there is little risk of mortar components contained in the concrete floating to the surface.

The concrete spread evenly on the road surface by the first screed 400 and the second screed 500 is finished by the reciprocating movement of the finishing trowel 800 located behind them in the front-rear and left-right directions. At this time, the first member 836 and the second member 838 of the trowel 830 can rotate relative to the hanging frame 820, so that the load transmitted to the trowel body 832 via the hanging frame 820 is directed outward along the first member 836 and the second member 838, as shown in FIG. 8. This prevents excessive load from being transmitted from the trowel body 832 to the concrete, suppressing damage to the flatness of the concrete pavement surface.

A person skilled in the art will easily understand that new embodiments can be created by omitting parts of the technical ideas of the above embodiments, combining parts of the embodiments as appropriate, or replacing parts of the embodiments with well-known technology.

As one example, the frame 200 of the concrete leveling device 100 is not limited to the above configuration, and can have any configuration that can perform the required functions. In addition, the frame 200 of the concrete leveling device 100 may be equipped with a mechanism that allows the width in the left-right direction to be adjusted as desired, so that it can be adapted to road surfaces with different construction widths.

REFERENCE SIGNS LIST 100 Concrete leveling device 200 Frame 220 Main frame 240 Subframe 250 Rail member 252 Rack 300 Travel device 400 First screed 500 Second screed 600 Vibration device 720 Differential mechanism 800 Finishing trowel 810 Support frame (mounting frame)
812 Roller 814 Actuator 816 Gear 820 Suspension frame (mounting frame)
832 Iron body 834 Bracket 836 First member 838 Second member 850 Reciprocating mechanism

Claims (5)

A frame,
A traveling device that causes the frame to travel;
A plurality of screeds extending in a left-right direction with respect to a traveling direction of the frame, arranged at positions spaced apart from each other in the traveling direction, and attached to the frame;
A vibration device attached to a screed located at the front end of the frame in the traveling direction;
A finishing trowel attached to the rear of the plurality of screeds and extending parallel to the traveling direction of the frame while reciprocating in the left and right directions relative to the traveling direction of the frame;
Equipped with
The vibration device generates vibration by an unbalanced weight rotated by an actuator.
Concrete spreading equipment. The multiple screeds reciprocate in the left and right directions in different phases from each other,
2. The concrete spreading device according to claim 1. The finishing trowel further reciprocates parallel to the travel direction of the frame.
The concrete spreading device according to claim 1 or 2 . The finishing trowel is
A trowel body extending parallel to the running direction of the frame;
a pair of brackets extending upward from two positions spaced apart from each other in an extension direction of the iron body on an upper surface of the iron body;
a first member connected to one of the pair of brackets so as to be capable of relative rotation;
a second member connected to the other of the pair of brackets so as to be capable of relative rotation;
a mounting frame that connects one end of the first member and one end of the second member so as to be capable of rotating relative to one another, and that mounts the iron body to the frame via the first member, the second member, and the pair of brackets;
Equipped with
One of the pair of brackets is slidable within a predetermined range in the extension direction of the iron body.
The concrete spreading device according to any one of claims 1 to 3 . A concrete spreading method using the concrete spreading device described in any one of claims 1 to 4 , traveling the frame with the traveling device, and spreading and leveling concrete on the target road surface while operating a vibration device attached to a screed located at the forefront in the traveling direction of the frame, and then further spreading and leveling the concrete on the target road surface with another screed , and increasing the flatness of the concrete spread and leveled on the target road surface with the finishing trowel .