Patent Grant
7524138
This invention relates to a floor surface finishing device which is used in a construction site for a final finishing operation on a surface of a concrete or mortar floor after casting.
When constructing a floor surface with concrete or mortar, conventionally, ready-mixed concrete cast in a construction area is leveled to form a floor and left for several hours. Then, the surface of the floor is evenly pressed using a plane leveling machine called a trowel to form a flat surface, followed by a manual operation of a skilled worker with a finishing iron (a square iron) for a final finishing.
A typical plane leveling machine used in the above-described floor construction is a machine having a rotary blade which rotates like a propeller along with a motor for driving the rotary blade (see Patent Document 1, for example). Normal operating steps are: on a floor surface to be finished after casting of ready-mixed concrete and leveling, the above-mentioned plane leveling machine is placed, and the machine is moved backward and forward and from side to side along the floor surface while rotating a rotary blade with a motor.
Patent Document 1: Unexamined Japanese Utility Model Publication No. Hei 5-57198 (pages 2-5, FIG. 1)
In a conventional floor finishing operation, after a pressing operation using a plane leveling machine according to the above-described steps, a skilled worker completes the finishing with a manual operation. This requires considerable work and time to complete a floor construction, and also a worker has to endure a large amount of physical load. During a final finishing step, in particular, a worker almost crawls along a floor surface keeping a low posture with his/her back bending at nearly 90 degrees, and steps backward by about 20 cm per each move while pressing the floor surface with a finishing iron in his/her hand moving from side to side. Thus, in practice, a great deal of time and work is expended by a skilled worker on the final finishing.
In addition, since a final finishing operation must be completed before concrete or mortar cast in an operation site is hardened, if a floor to be constructed is wide, more than one skilled worker is needed. However, under a current situation where the number of skilled workers is decreasing, it is difficult to employ the necessary number of workers.
Furthermore, in a final finishing operation, as a worker has to remain in an unnatural posture over hours, the physical burden on his/her feet, back and/or shoulders is extremely large. Skilled workers engaging in final finishing operations, who have repeated such operations over a long period of time, suffer from chronic backache or shoulder ache even after finishing their operations.
An object of the present invention is to provide a floor surface finishing device which is easy to handle, capable of completing a final finishing operation on a floor surface in a relatively short time, and makes it possible to reduce the number of operators.
A floor surface finishing device according to the present invention comprises a plane leveling machine having a plurality of rotary blades which rotate in a propeller manner by a driving force while keeping in contact with a floor surface to be finished. A planar finishing blade which is connected to the plane leveling machine is disposed in a part of outer peripheral regions of planes of rotation (at an outer periphery of the circular area of rotation) of the rotary blades. The finishing blade is disposed so that at least a part of the finishing blade is brought into contact with the floor surface after the rotary blades have come into contact with and passed over the floor surface.
The floor surface finishing device having the above-described structure is placed on a floor surface to be finished, the rotary blades of the plane leveling machine are rotated by a driving force, and the whole of the floor surface finishing device is moved along the floor surface in a horizontal direction while maintaining the rotary blades preceding the finishing blade. Thus, the floor surface to be finished is leveled with pressure by the rotary blades, thereby completing a final finishing operation with the following finishing blade. Then, as the finishing blade is disposed so that at least a part of the finishing blade is brought into contact with the floor surface after the rotary blades have come into contact with and passed over the floor surface, the final finishing operation can be securely completed on the floor surface leveled by the rotary blades with pressure.
As described above, the floor surface finishing device can conduct both a leveling operation with pressure and a final finishing operation simply by moving the whole device along the floor surface to be finished in a horizontal direction. The device can be handled in an easy manner so that a final finishing operation of a floor surface can be completed in a relatively short time. Furthermore, since both a leveling operation with pressure and a final finishing operation can be achieved by one operator, the number of operators can be reduced and no skilled workers are needed.
Preferably, the above finishing blade may be slanted to have an angle of attack toward a pivotal center of the rotary blades. The finishing blade arranged in this manner can be moved forward while maintaining an angle of attack toward a moving direction of the floor surface finishing device, leading to a further improved final finishing.
In this case, preferably, an angle adjusting mechanism may be provided to vary an angle of attack of the finishing blade. With the angle adjusting mechanism, an angle of attack of the finishing blade can be set depending on each condition of constructing a floor surface. Thus, a suitable final finishing operation can be conducted in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
It is also preferable that the above finishing blade may be movable in a direction including a moving direction along a pivotal center of the rotary blades (i.e., towards and away from the floor surface to be finished 2a). By this structure, the finishing blade can either come into contact with or separate from a floor surface to be finished (such floor surface being brought into contact with planes of rotation of the rotary blades). In other words, as the finishing blade can come into contact with or separate from a floor surface according to need, the finishing blade can be handled in an easy manner, improving its operability.
In addition, preferably, a pressing means may be provided to press the finishing blade against the floor surface to be finished. With this pressing means, the pressing force of the finishing blade against the floor surface can be increased, and thus the flattening and finishing efficiency to the floor surface is enhanced, which enables further improvement in the final finishing. Here, provided with a variable pressing force of the pressing means, a suitable final finishing operation can be conducted in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
In this case, a plumb bob provided as the above pressing means exhibits a secure pressing effect despite its simple mechanism, and the pressing force can be varied simply by adjusting the weight of the plumb bob. Accordingly, as in the above-described cases, a suitable final finishing operation can be conducted in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
It is also preferable that the finishing blade may be rotatable (swingable) around the rotary blades. By this structure, positional relations between an operator who handles the floor surface finishing device, the rotary blades, and the finishing blade can be varied. Therefore, while maintaining the positional relation in which the rotary blades are firstly brought into contact with a floor surface to be finished before the finishing blade comes into contact with the floor surface, an operator can move the floor finishing device in a direction to the back of the operator (in a pulling direction) or move the floor finishing device from side to side of the operator. Thus, operability and safety when conducting a finishing operation of a floor surface adjacent to a wall or pillar, or a floor surface with obstacles such as a hole, groove or protruding member, can be further enhanced.
Preferably, at least a part of the finishing blade may be formed of a flexible elastic plate. By this structure, when the finishing blade presses a floor surface to be finished, at least a part of the finishing blade bends so as to elastically press the floor surface, enabling tighter contact to the floor surface. Accordingly, the finished effect of a floor surface immediately after and over which the rotary blades have passed is improved, and a final finished surface has an excellent appearance.
It is also preferable that the finishing blade may be detachable from the plane leveling machine. By this structure, the finishing blade can be changed depending on conditions of a construction site, and a worn or damaged finishing blade can be replaced. Therefore, an optimal finishing operation is conducted in accordance with each construction site, and maintenance is also easier.
As another structure, a seat for an operator may be provided on a part of the plane leveling machine. By this structure, an operator can sit on the seat when conducting a floor finishing operation, which greatly alleviates a physical load of the operator.
According to the present invention, the following advantages can be obtained.
(1) A plane leveling machine has a plurality of rotary blades which rotate in a propeller manner by a driving force while keeping in contact with a floor surface to be finished, and a planar finishing blade which is connected to the plane leveling machine and is disposed in a part of outer peripheral regions of planes of rotation of the rotary blades. The finishing blade is disposed so that at least a part of the finishing blade is brought into contact with the floor surface after the rotary blades have come into contact with and passed over the floor surface. Thus, the device can be handled in an easy manner so that a final finishing operation of a floor surface can be completed in a relatively short time. Furthermore, the number of operators including skilled workers can be reduced.
(2) Because the finishing blade is slanted to have an angle of attack toward a pivotal center of the rotary blades, the finishing blade can be moved forward while maintaining an angle of attack toward a moving direction of the floor surface finishing device, leading to a further improved final finishing.
(3) Because an angle adjusting mechanism can vary an angle of attack of the finishing blade, the angle of attack of the finishing blade can be set depending on each condition of constructing a floor surface. Thus, a suitable final finishing operation can be conducted in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
(4) Because the finishing blade is movable in a direction including a moving direction along a pivotal center of the rotary blades, the finishing blade can come into contact with or separate from a floor surface to be finished according to need. Therefore, the finishing blade can be handled in an easy manner, improving its operability.
(5) Because the pressing means presses the finishing blade against a floor surface to be finished, the pressing force of the finishing blade against the floor surface can be increased. Thus, the flattening and finishing efficiency of the floor surface is enhanced, which enables further improvement in the final finishing.
(6) Because a plumb bob is provided as a pressing means, a secure pressing effect is obtained despite its simple mechanism, and the pressing force can be varied simply by adjusting weight of the plumb bob. Accordingly, a suitable final finishing operation can be conducted in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
(7) Because the finishing blade rotates around the rotary blades, positional relations between an operator who handles the floor surface finishing device, the rotary blades, and the finishing blade can be varied. Accordingly, the positional relation can be set depending on conditions of a construction site, improving operability and safety.
(8) Because at least a part of the finishing blade is formed with a flexible elastic plate, a finishing effect of a floor surface immediately after the rotary blades have passed is improved, and a final finished surface has an excellent appearance.
(9) Because the finishing blade is detachable from the plane leveling machine, the finishing blade can be changed depending on conditions of a construction site, and a worn or damaged finishing blade can be replaced. Therefore, an optimal finishing operation is conducted in accordance with each construction site, and maintenance is also easier.
(10) Because a seat for an operator is provided on a part of the plane leveling machine, an operator can sit on the seat when conducting a floor finishing operation, which greatly alleviates the physical load on the operator.
With reference to
As shown in
The connecting member 6 comprises the above-mentioned vertical shaft 6a, a horizontal shaft 6d horizontally extending from the vertical shaft 6a, a supporting member 6e fixed aslant between the vertical shaft 6a and the horizontal shaft 6d, and an elevating arm 6f having a base end portion pivotally supported by the supporting member 6e. The base end portion of the elevating arm 6f is pivotally supported in a detachable manner by one of a plurality of mounting holes 6h which are open on the supporting member 6e via a mounting pin 6g. The base end portion of the elevating arm 6f can be selectively attached to one of the plurality of mounting holes 6h. Whichever of the mounting holes 6h is selected, the elevating arm 6f can be rotatable in upper and lower directions centering around the mounting pin 6g.
On a distal end portion of the elevating arm 6f, a fixing member 12 having an L-shaped section is fixed in a horizontal direction so as to form a T-shape with the elevating arm 6f and the fixing member 12 taken in a plan view. The planar finishing blade 8 is attached to the fixing member 12 along a longitudinal direction thereof. The finishing blade 8, which is fixed on a bottom surface of the fixing member 12 with a screw 13, is detachable from the fixing member 12 by loosening the screw 13. Thus, the finishing blade 8 can be replaced by another finishing blade with a different size, thickness or material depending on each construction condition such as a type or property of a floor surface to be finished. If a thumbscrew is used instead of the screw 13, the finishing blade can be detached without using tools such as a wrench.
Above a connecting portion of the elevating arm 6f and the fixing member 12, a horizontal bar 14 is provided parallel to the fixing member 12. Two plumb bobs 15 are attached to the horizontal bar 14 at symmetrical positions on both sides of the connecting portion. On a rear side of the connecting portion of the elevating arm 6f, a rotatable pulley 16 is disposed. A wire 17 having a distal end portion mounted on the horizontal shaft 6d, is hung on the pulley 16 to form a U-shape. A base end portion of the wire 17 passes through a guide hole 19a of a wire guide 19 on a distal end portion of the horizontal shaft 6d and is mounted to an elevating lever 18 of the operating handle 9.
In a state in which the connecting member 6 is being connected to the support 10, as shown in
Here, a use of the floor surface finishing device 1 is explained below. As shown in
By the above operation conducted by an operator, the floor surface to be finished 2 is leveled with pressure by the rotary blades 8, followed by a final finishing by the finishing blade 8. At this time, the finishing blade 8 is arranged so that an area close to one of the longitudinal sides of the finishing blade 8 is brought into contact with a floor surface to be finished 2a immediately after the rotary blades 4 have come into contact with and passed over the floor surface to be finished 2a. Accordingly, the floor surface to be finished 2a which has been leveled with pressure by the rotary blades 4 can be subject to a final finishing.
As described above, the floor surface finishing device 1 can level a floor surface with pressure and conduct a final finishing simply by rotating the rotary blades 4 with the motor 3 and horizontally moving the whole of the floor surface finishing device 1 to the direction of the arrow A along the floor surface to be finished 2 utilizing the rotary movement of the rotary blades 4. Therefore, the device is easy to handle and can complete a final finishing operation of the floor surface to be finished 2 in a relatively short time. Moreover, only one operator is necessary to manipulate the floor surface finishing device 1 to conduct both a leveling operation with pressure and a final finishing operation, which reduces the number of operators and does not need skilled workers.
In the above-described embodiment, the finishing blade 8 is tilted so as to have an angle of attack θ toward a pivotal center C of the rotary blades 4. In other words, the finishing blade 8 is angled upwards towards the center axis of rotation C of the rotary blades 4 so as to form an angle θ with respect to the surface to be finished 2a, as shown in
In addition, as an angle adjusting mechanism to vary the angle of attack θ of the finishing blade 8, provided are the supporting member 6e having the plurality of mounting holes 6h and the elevating arm 6f which can be pivotally supported by one of the mounting holes 6h selectively. Accordingly, if the base end portion of the elevating arm 6f is pivotally supported by the mounting holes 6h located on an upper side and close to the horizontal shaft 6d, the angle of attack θ of the finishing blade 8 becomes larger. On the other hand, if the base end portion of the elevating arm 6f is supported by the mounting holes 6h located on a lower side and close to the vertical shaft 6a, the angle of attack θ of the finishing blade 8 becomes smaller.
With the angle adjusting mechanism described above, the angle of attack θ of the finishing blade 8 can be set depending on construction conditions of the floor surface to be finished 2, and thus a suitable final finishing operation can be conducted in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
By tilting the elevating lever 18 provided on the operating handle 9, the elevating arm 6f moves (pivots) up and down centering around the mounting pin 6g via the wire 17. Thus, the elevating arm 6f forms part of a lifting mechanism for moving the finishing blade 8 in upper and lower directions (a direction substantially parallel to the pivotal center C of the rotary blades 4 and away from and toward the surface to be finished 2a). Thus, the finishing blade 8 can be brought into contact with or separate from the floor surface to be finished 2 which comes into contact with the planes of rotation 7 of the rotary blades 4. Namely, by tilting the elevating lever 18 according to need, the finishing blade 8 can either come into contact with or separate from the floor surface to be finished 2, thereby realizing easier handling and enhancing operability.
Furthermore, the plumb bob 15 for pressing the finishing blade 8 against the floor surface to be finished 2a increases the pressing force of the finishing blade 8 onto the floor surface to be finished 2a. Therefore, an excellent finishing effect on the floor surface to be finished 2a can be obtained to improve the condition after final finishing. In addition, since the plumb bob 15 can be detached from the horizontal bar 14, the weight of the plumb bob 15 can be changed by varying the volume, number or material thereof. A suitable final finishing operation can be conducted in this manner in accordance with the type, property or curing condition of a floor surface material such as concrete or mortar.
As described above, the finishing blade 8, which is horizontally rotatable (pivotable) centering around the hook 11, can be horizontally rotated (swung) around the rotary blades 4 and held at an optional position. Therefore, it is possible to change a positional relation between an operator (not shown) standing near an end portion of the operating handle 9 to manipulate the floor surface finishing device 1, the rotary blades 4, and the finishing blade 8. Thus, in addition to a basic use for conducting a floor finishing operation shown in
Specifically, as shown in
The rotary blades 4 rotate clockwise in a plan view (a state shown in
In this embodiment, the finishing blade 8 is formed of a flexible elastic plate (a stainless steel plate or a special steel plate having a thickness T of 0.3 to 0.7 mm, a width W of 50 mm to 250 mm, and a length L of 700 mm to 3000 mm, for example). This enables tighter contact to the floor surface to be finished 2a immediately after the rotary blades 4 have passed, and a final condition after finishing is excellent in its appearance.
The length L of the finishing blade 8 is larger than a diameter of the plane (circular area) of rotation 7 of the rotary blades 4, and a direction along the length L of the finishing blade 8 is arranged parallel to a tangential direction of an outer periphery of the plane (circular area) of rotation 7. In this manner, after the rotary blades 4 have come into contact with and passed over the floor surface to be finished 2a, the finishing blade 8 is always brought into contact with and passes over the floor surfaces to be finished 2a to complete a final finishing, which secures a final finishing operation. The use of the floor surface finishing device 1 can shorten the work period for a floor surface finishing operation up to one-seventh to one-tenth compared to conventional construction methods.
In the floor surface finishing device 1 of the present (first) embodiment, an operator manually conducts up-and-down moving operations of the finishing blade 8 (moving operations in a direction including a moving direction parallel to the pivotal center C of the rotary blades 4) and a horizontal rotating operation of the finishing blade 8 centering around the hook 11. Alternatively, these operations can be motorized by providing mechanisms powered by the motor 3 or by an electric motor with a battery as a power source, such as a hydraulic, gear, wire, link, belt, chain and cam mechanisms. With the mechanisms, physical load of an operator can be further alleviated.
Next, with reference to
A finishing blade 8b shown in
On a surface of a finishing blade 8c shown in
When using a finishing blade 28 shown in
Between a vicinity of a center of the upper edge of the mounting member 26i and a vicinity of the distal end of the elevating arm 26f is a link mechanism 20 which comprises two connecting members 20a and 20c connected to each other by a hinge portion 20b. An end portion of the connecting member 20a is firmly fixed to the upper edge of the mounting member 26i. A connecting hole 26e of a U-shaped connecting portion 20d firmly attached to an end portion of the connecting member 20c is brought to correspond with one of a plurality of connecting holes 26k which are opened on a connecting member 26j firmly fixed to a vicinity of the distal end of the elevating arm 26f. Then, a pin 20e is inserted into the connecting holes 26e and 26k so that the mounting member 26i along with the finishing blade 28 and the other members are fixed to the elevating arm 26f.
In this case, depending on the hole among the plurality of connecting holes 26k on the connecting member 26j selected to correspond with the connecting hole 26e of the connecting portion 20d on the end portion of the connecting member 20c, an angle of the mounting member 26i mounted to the elevating arm 26f can be set. Thus, an angle of attack θ of the finishing blade 28 to the floor surface to be finished 2a can be selectively set, thereby obtaining the optimal angle of attack θ for each operating condition.
Next, with reference to
In the floor surface finishing device 30 shown in
When the elevating lever 31 is tilted, the wire 37 is let in and out, thereby sliding the elevating arm 36f upward and downward along a longitudinal direction of the tubular member 36b. In this manner, a finishing blade 8 can come into contact with or separate from a floor surface to be finished 2a. In the case of the floor surface finishing device 30, an elevating mechanism for the finishing blade 8 can be formed of the tubular member 36b and the elevating arm 36f, which simplifies the structure of the device.
In the floor surface finishing device 40 shown in
When the elevating lever 41 is tilted, the wire 47 is let in and out, thereby rotating the elevating arm 46f centering around the shaft 46g in a predetermined angle. In this manner, a finishing blade 8 can come into contact with or separate from a floor surface to be finished 2a. In the case of the floor surface finishing device 40, the finishing blade 8 can be lifted and lowered by rotation of the elevating arm 46f which is relatively short. Thus, the elevating mechanism can be made compact. In addition, when the elevating arm 46f is lifted up to be nearly vertical by largely tilting the elevating lever 41, the finishing blade 8 as well as a plumb bob 15 can be housed on a side of the plane leveling machine 5. In this case, the plumb bob 15 approaches a center of gravity of the plane leveling machine 5, which prevents decline of operability when only the function of the plane leveling machine 5 is used for operation.
Next, in the floor surface finishing device 50 shown in
A wire 57a with its distal end portion fixed on a top surface of the distal end portion of the auxiliary elevating arm 56d extends through the pulley 50c and the pulley 50d and is fixed to the pulley 50c. A wire 57b with its distal end portion fixed on a bottom surface of the auxiliary elevating arm 56d extends through the pulley 50a and the pulley 50b and is fixed to an auxiliary elevating lever 51b.
When the elevating lever 51a is tilted, the wire 57a is let in and out, thereby rotating the auxiliary elevating arm 56d centering around the shaft 56c. At this time, the elevating arm 56f rotates (pivots) centering around the shaft 56a in a relatively large motion via the wire 57b in a state of being stretched between the pulleys 50a and 50b. Therefore, a finishing blade 8, a plumb bob 15 and other members can be lifted and lowered within a relatively wide range of height. On the other hand, when the auxiliary elevating lever 51b is tilted, the wire 57b is let in and out, thereby rotating the elevating arm 56f centering around the shaft 56g within a relatively narrow range so that the finishing blade 8 can come into contact with and separate from a floor surface to be finished 2a.
Accordingly, during floor finishing operations, the auxiliary elevating lever 51b is manipulated to make the finishing blade 8 come into contact with and separate from the floor surface to be finished 2. After completing the floor finishing operations, the elevating lever 51a is manipulated to lift up high the finishing blade 8, the plumb bob 15, and other members. In this manner, in the floor surface finishing device 50, by tilting operations of each of the elevating lever 51a and the auxiliary elevating lever 51b which are disposed at the hands of an operator standing at a position of the operating handle 9, the finishing blade 8 can be moved in lifting and lowering directions, which leads to easy manipulation and excellent operability.
Next, with reference to
The floor surface finishing device 60 shown in
While rotating the rotary blades 4 of the plane leveling machine 165 with a part of the finishing blade 68 coming into contact with a floor surface to be finished 2a, an operator sitting on the seat S moves the floor surface finishing device 60 forward (toward a left side in
Next, in the floor surface finishing device 70 shown in
Next, in the floor surface finishing device 80 shown in
The place where the electrically-driven hoist 61 used in the floor surface finishing devices 60, 70 and 80 is installed is not limited to the positions shown in
In the floor surface finishing devices 1, 30, 40, 50, 60, 70 and 80, a wire is used as a mechanism for lifting and lowering a finishing blade, and a human power or an electric motor is used as a driving power thereof. However, the present invention is not limited to these members. The mechanism for lifting and lowering a finishing blade can be composed of an air cylinder activated by an electric motor or a motor, a link mechanism using a hydraulic cylinder, a belt mechanism, a chain mechanism, a cam mechanism, or the like, and the elevation of the finishing blade and the adjustment of an angle of attack can be conducted with a switching operation. When employing an air cylinder, a hydraulic cylinder, or the like, the finishing blade can not only be moved upward and downward but also be maintained at a predetermined position and with a predetermined angle of attack. Therefore, it is also possible to omit a plumb bob which is used as a pressing means against a floor surface to be finished.
Next, with reference to
In the floor surface finishing device 90 shown in
Closely to a distal end of the elevating arm 96f, an angle adjusting lever 92a, as well as the finishing blade 8 which rotates centering around a shaft 93, and a mounting member 92b which defines a holding position of the angle adjusting lever 92a, are provided. Thus, by changing the holding position of the angle adjusting lever 92a in relation to the mounting member 92b, an angle of attack θ of the finishing blade 8 can be varied.
Next, in the floor surface finishing device 100 shown in
The floor surface finishing device in the present invention can be widely used in an industrial field where finishing operations of concrete floor surfaces or mortar floor surfaces are conducted.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-392864 | Nov 2003 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2004/017289 | 11/19/2004 | WO | 00 | 5/5/2006 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2005/049940 | 6/2/2005 | WO | A |
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| 20070071553 A1 | Mar 2007 | US |
