JPH05287883A - Floor panel binding frame - Google Patents

Abstract

PURPOSE:To make it difficult for connected floor plate material binding frames to be bent upward and downward at the mutually connected part thereof. CONSTITUTION:A frame 1 is formed by a square bottom plate 2 and the peripheral walls 3, 3... of four sides thereof. In the peripheral walls 3, 3..., connecting tongue piece 13 projected outward and inward piercing connecting holes 14 are formed in symmetrical positions, on every side locking projections 15 are formed on the points of the connecting tongue pieces 13, 13..., and locking lateral rods 16 locked 18 the locking projections 15 are formed in the connecting holes 14, 14.... Further, a engaging grooves 18 continuing to the lower part of the bottom plate 2 are formed below the connecting tongue pieces 13, and floating preventing pieces 17 projected from the peripheral walls 3 are projected below the connecting holes 14 facing to the grooves 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floor board material used for holding wooden floor board materials and connecting adjacent floor board materials to each other when a wooden floor board material is stretched on a floor base of various buildings. It is related to the binding frame.

[0002]

2. Description of the Related Art Conventionally, as for floor board materials, in the case of reinforced concrete constructions, etc., where wooden floors are stretched, it is generally affixed to the floor base with an appropriate adhesive. It was being done.

[0003]

The floor board material stretched as described above gradually becomes painful after a few years of use, and it is necessary to replace it. However, as mentioned above, if it was adhered with an adhesive, its peeling is also difficult,
Furthermore, it cannot be said that the tensioning work itself is originally easy.

Although it has not been publicly known, a floor is constructed by tying a coupling frame for holding a floor plate, which is a frame for holding a floor plate, onto a floor base while coupling them together. We proposed a binding frame that can be used (Japanese Patent Application No. 4-57).
346). Explaining this a little in detail, "
It is configured in a box shape consisting of a quadrilateral bottom plate and a peripheral wall that rises from each side thereof, and in the bottom plate, a plurality of reinforcing ridges that also serve as a pedestal on which the floor plate material is placed are vertically and horizontally formed, It is a floor board material connecting frame which is formed on the peripheral wall of each side of the frame by connecting means for mutually connecting the sides of the adjacent frame ".

According to this, the floor can be completed very easily by arranging the coupling frames holding the floor board materials on the floor base while coupling them to each other. Further, partial floorboard replacement is also very easy because they are not glued together. Although it has such an advantage, if you dare raise the problem, if you pull up the joint part of the adjacent floor board by some means (this is not easy because the gap is narrow), fold here. It is possible that they will be in a tune and will surface.

The present invention, however, has the following problems.
That is, when the floor board material connecting frame is to be pulled up by the mutually connecting portions arranged adjacent to each other, it is intended to solve the problem that it may be in a bent state and float up here. is there.

[0007]

The gist of the structure of the present invention is that the frame is formed in a box shape consisting of a quadrilateral bottom plate and peripheral walls rising from each side, and the peripheral wall of the frame is formed. A connecting tongue piece, a connecting hole, an anti-floating piece, and an engaging groove, and the connecting hole is a hole into which the connecting tongue piece on the peripheral wall of another frame installed adjacently can be inserted. , A hole provided with an engaging portion for preventing the connecting tongue piece inserted thereinto from falling down, the engaging groove being provided on the peripheral wall of another frame body adjacent to the engaging groove. A floor board material coupling frame configured as a groove into which a floating prevention piece can be engaged and which is a downward groove that prevents the engaged floating prevention piece from rising upward.

The floor board material is a floor board material arranged on a floor base and is made of wood. It is a square such as a square or a rectangle when viewed from a plane. It is appropriate that these floor boards have a configuration in which the portion above the upper end of the peripheral wall is overhung by the thickness of the peripheral wall so that the peripheral wall of the floor plate connecting frame cannot be seen from the floor surface after being stretched on the base. Is. Further, as will be described later, in the case where the peripheral wall is provided with a locking brim that extends obliquely downward from the upper portion of the inner surface thereof, the lower end of the locking brim is located at a corresponding position on the circumferential side of the floor plate. It is preferable to form and place a locking groove for locking.
Of course, it is not inconvenient not to configure the locking groove.

It goes without saying that the frame body has a planar shape determined in accordance with the size and shape of the target floor plate material. As described above, since the floor board material is formed in a square shape, the frame body is also formed based on a corresponding square shape. Further, as described above, it is preferable that a plurality of locking flanges inclined downward from the upper middle portion of the inner surface of the frame are juxtaposed on the peripheral wall of the frame. Due to the elasticity of the material of which the locking collar is made, the locking brim has an overhanging dimension that allows deformation when the floor board is loaded into the frame so that the floorboard can be smoothly loaded.

It is preferable that a plurality of reinforcing ridges, which also serve as pedestals on which the floor plate material is placed, are erected vertically and horizontally on the bottom plate. It is suitable to form a lattice. Further, it is preferable that the bottom plate of the frame body is provided with a plurality of coupling stands scattered at the same height as the reinforcing ridges, and screw holes penetrating the front and back sides are formed in each of the coupling stands.

In addition, a leg member is prepared in which leg holes are formed near the four corners of the bottom plate, and the base portion has a thickness corresponding to the height of the reinforcing ridge and the leg body is hung from the center of the lower portion thereof. It is preferable that the legs of the leg members project from the leg holes and hang down. The leg members are preferably made of a rubber member having elasticity, for example, synthetic rubber such as neoprene. The base of the leg member is restrained from above by the floor plate material set in the frame.

The connecting tongue piece and the connecting hole are arranged, for example, by disposing the connecting tongue piece on the peripheral walls of two adjacent sides of the frame and by disposing the connecting hole on the peripheral walls of the other two adjacent sides. It can be configured to. Alternatively, the coupling tongue and the coupling hole may be arranged such that the coupling tongue and the coupling hole are symmetrically arranged with respect to each other on the peripheral wall of each side of the frame. Of course, other configurations can be adopted.

The connecting tongue may have various configurations. For example, the tongue is a tongue protruding outward from the outer surface of the peripheral wall of the frame, and the tongue-shaped member has a locking projection hanging down from the tip thereof. It can be configured in the body, when the coupling tongue is configured in this way, the coupling hole is a hole which is formed at a corresponding position of the peripheral wall of the frame body, into which the tongue can be inserted, As the engaging portion inside thereof, it is possible to use a hole formed in a locking lateral bar that engages with the locking projection and is prevented from falling downward.

The anti-floating piece and the engaging groove are, for example, the anti-floating piece on the peripheral walls of two adjacent sides of the frame, and the engaging groove on the peripheral walls of the other two adjacent sides. It is possible to arrange one each. Although it can be provided at a position completely different from the connecting tongue and the connecting hole,
It is suitable that the anti-floating piece is configured in a positional relationship below the coupling hole and the engagement groove is configured in a positional relationship below the coupling tongue piece. The floating prevention piece may basically be formed as a tongue or a plate, but is formed as a plate (tongue) in which edge walls are raised on both sides and a screw hole is formed near the center. Is appropriate.

The frame body and all the constituent elements of the frame body are preferably integrally formed of plastic having a slight elasticity.

[0016]

Since the present invention is constituted as described above, when the floor board is stretched on the floor base of the building, the frame is preliminarily provided under the target floor board, and By arranging the floor board material on the corresponding base while connecting the connecting means of the exterior frame bodies to each other, the floor can be easily constructed.

The floor board can be loaded into the frame by simply pushing it in from above. In the case where the locking brim is extended on the upper part of the inner surface of the peripheral wall, the circumferential side of the floor plate is clamped by the locking brim, and a certain degree of holding is secured.
When the locking groove is formed on the peripheral side of the floor plate so as to correspond to the above-mentioned locking flange, and the floor plate is loaded into the frame as described above, The outer end is pushed into the locking groove and is firmly held. When the floor board material is loaded into the frame, the locking collar elastically retracts in the peripheral wall direction, so that smooth loading can be ensured.

In the case where the bottom plate of the frame body is dotted with the connecting bases having the screw holes at the same height as the reinforcing ridges as described above, after the floor board material is loaded into the frame body, This is turned upside down and a screw is inserted from the screw hole, and screwed into the floor plate material to secure the fixing. When the frame is not provided with the locking brim or the coupling base having the screw hole, an adhesive agent is applied to the lower surface of the floor plate material, the adhesive is applied to the frame body, and both are bonded.

Further, when the bottom plate of the frame body is provided with leg holes near the four corners and the leg members are prepared, the leg members are attached to the legs before the floor plate material is set on the frame body. The body is arranged so as to project and hang from the leg hole. The base portion of the leg member is restrained from above by the floor plate material set in the frame body.

The operation of tensioning the floor board material to the floor base can be performed by sequentially arranging the other floor board materials on the arranged floor board materials while bringing their sides into contact with each other. When the sides are brought into contact with each other, they are easily adjacent to the floor plate material already arranged by engaging the connecting tongue piece of the frame body mounted on the lower part of each with the connecting hole and the floating preventing piece and the engaging groove. It is possible to combine the floor plate materials arranged in this manner. Then, by repeating such work, it is possible to perform the work of tensioning the floor board material very easily.

Further, after the tensioning is completed, the floor board members are firmly connected to each other by the connecting tongue piece of the frame body mounted on the lower part and the connecting hole, and further, the floating preventing piece and the engaging groove are engaged with each other. ,
It is possible to prevent levitation in a bent state at a joint portion between adjacent floor board materials. Furthermore, when an overhang corresponding to the thickness of the peripheral wall of the frame is placed on the upper part of the floor board on the peripheral side, the frame cannot be seen at all after installation on the floor base.

In addition, when such a floor board material is seriously damaged due to long-term use and needs to be re-covered, basically, they are connected to each other by a connecting tongue piece, a connecting hole and a connecting hole of the frame. Only joined by the anti-floating piece and the engaging groove,
It is not fixed to the base such as a floor base (sometimes fixed, but not entirely attached)
Therefore, it is easy to remove. Especially if you remove a part of the floorboard, if you remove it from the floorboard at that position,
It can be removed only by releasing the connection of the connection tongue and the like. Therefore, the work of relining the floor board can be performed very easily. Further, since the floor board material is reinforced by the frame body, it is possible to secure a sufficient strength even with a considerably thin board.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the frame body 1 is basically composed of a square bottom plate 2 when viewed from above and peripheral walls 3, 3, ... Standing on the four sides of the bottom plate 2. The bottom plate 2
As shown in FIG. 1, FIG. 3, FIG. 4, FIG. 7 and FIG. 8, a plurality of reinforcing ridges 5, 5, ... Also serving as a pedestal on which the floor board 4 is placed are arranged vertically and horizontally. It will be constructed in a grid pattern when viewed from the top, with two sections each rising up into nine sections. Also, the bottom plate 2
Further, the coupling stands 6, 6, ... Which are the same height as the above-mentioned reinforcing ridges 5, 5 ,. As shown in FIG. 1, in particular, these connecting bases 6, 6, ... Are located at four locations in contact with the center of each side of the frame 1 among the square sections formed by the reinforcing ridges 5, 5 ,. It will be launched inside. Further, screw holes 7 are drilled in the coupling bases 6, 6 ,.

Further, one or more water-permeable holes 8 penetrating through the front and back are formed in the bottom plate 2 of each section constituted by the reinforcing ridges 5, 5, ....

In addition, in the bottom plate 2, partition ridges 9 and 9 parallel to the peripheral walls 3 and 3 are raised in the compartments formed at the four corners, and the interior of the leg compartment thus constructed. A leg hole 10 is formed in the center of the bottom plate 2. The partition ridges 9 and 9 are formed at the same height as the reinforcing ridges 5, 5 ...
On the other hand, as shown in FIG. 6, FIG. 7 and FIG.
Is a plane square having the same size as the shape of the leg section, and has a thickness corresponding to the height of the section projections 9 and 9 and the reinforcing projections 5, 5, ..., From the lower center of the base 11a to the leg 11a.
Prepare the leg member 11 in which b is hung. The leg 11b
Has a size such that it can be fitted into the leg hole 10. The leg member 11 is made of synthetic rubber having elasticity.

The peripheral walls 3, 3, ... Are provided in FIGS.
Further, as shown in FIG. 8, in the middle of the upper portion of the inner surface thereof, one diagonally downward locking brim 12 is extended at the center in the left-right direction.

The peripheral walls 3, 3, ...
As shown in FIGS. 7 and 9, for each peripheral wall 3 on each side, a coupling tongue piece 13 protruding outward and a coupling hole 14 penetrating inward are provided.
Are arranged in symmetrical positions. The connecting tongue pieces 13, 13
Is formed with a locking projection 15 that hangs at its tip, and the coupling holes 14, 14 are formed with a horizontal locking bar 16 inside which the locking projection 15 is locked.

Further, on the peripheral walls 3, 3, ..., As shown in FIGS. 1 to 3, 7 and 9, a floating prevention piece 17 and an engaging groove 18 are formed. The floating preventing pieces 17 are formed so as to project below the coupling hole 14 in the peripheral wall 3 on each side. The floating prevention piece 17 is basically configured as a tongue-shaped body, and edge walls are raised on both sides of the tongue-shaped body, and a screw hole 19 is formed near the center. The lower surface of the floating prevention side 17 is made to coincide with the lower surface of the bottom plate 1. Further, the engaging groove 18
Is formed below the protruding position of the coupling tongue piece 13. A downward groove is formed from the peripheral wall 3 toward the bottom portion 3.

The frame 1 and each of the constituent elements of the frame 1 are integrally formed of plastic whose main material is polypropylene.

Since this embodiment has the above-mentioned structure, when the floor board members 4, 4 ...
The floor frame members 4, 4 ... Are covered with the connecting frames, and the floor plate members 4, 4, ... Are connected to the connecting tongue piece 13, the connecting hole 14, and the floating preventing piece of the frame body 1. 17 and the engaging groove 18 are fitted into each other, and the locking projection 15 of the coupling tongue piece 13 is engaged with the locking lateral bar 16 of the coupling hole 14 so that they are coupled to each other on the floor substrate. To form a floor.

By the way, in this embodiment, since the floor board material connecting frame is constructed as described above, the target floor board material 4 used is as follows. That is, as shown in FIG. 5, the floor plate 4 is made of wood, but is square when viewed from the top, and the upper edges of the four side walls are the thickness of the peripheral walls 3, 3, ... Of the frame 1. It has an overhang 4a extended outwardly by an amount, and the lower part thereof is the exterior portion 4b.

Prior to the work of tensioning the floor board members 4, 4 ... to the floor base, first, it is necessary to set a connecting frame on the lower outer periphery of the floor board members 4, 4 ,. The leg members 11 are set in the leg holes 10, 10, ... Of the bodies 1, 1. That is, as shown in FIGS. 7 and 9, the leg 11a is fitted into the leg section while the base 11a is fitted into the leg compartment.
That is, b is inserted into the leg hole 10 and hung down.

As described above, the frame bodies 1, 1, ... Are set on the floor plate members 4, 4, ... After setting the leg members 11, 11 ,. Then, the floor board material 4 is on the lower side,
That is, the outer sheathed portion 4b on the peripheral side is inserted into the peripheral walls 3, 3 ... Of the frame body 1. At this time, the locking flanges 12 of the peripheral walls 3, 3 ,.
12 ... is molded of plastic whose main material is polypropylene, and has some elasticity, so that the peripheral wall 3,
It can be elastically deformed in the 3 ... direction and can be inserted smoothly. The floor plate 4 may be inserted until the lower surface of the floor plate 4 comes into contact with the upper ends of the reinforcing ridges 5, 5 ..., the partition ridges 9, 9 ,. The lower ends of the locking collars 12, 12 ... Are brought into pressure contact with the peripheral portion 4b on the peripheral side, and the floor plate material 4 is fixed to the frame 1 to a considerable extent.

Thereafter, the frame 1 having the exterior portion 4b of the floor board 4 inserted therein is turned upside down, and as shown in FIG. 8, the screws 20 are inserted from the screw holes 7 of the respective coupling tables 6, 6 ... Insert and screw into the floorboard 4. In this way, the exterior portion 4b of the floor board member 4 is firmly fixed in the frame body 1. In this way, the base 11a is restrained from above by the floor plate member 4 so that the leg member 1
.. are also fixed to the frame body 1.

In the floor board material connecting frame, since the bottom plate 2 of the frame body 1 is provided with the reinforcing ridges 5, 5, ..., The floor board material itself has sufficient strength, and the floor board material to be loaded therein. 4 results in being sufficiently reinforced. Therefore, the strength of the floor board material 4 is not so required.

After that, the exterior portion 4b is processed as described above.
The flooring can be performed by arranging the floor plate materials 4, 4 ... Having the frame body 1 mounted on them on the floor base while abutting any of the adjacent sides. At this time, the connecting tongue pieces 13 and the connecting holes 14 are symmetrically arranged on the four peripheral walls 3, 3, ... Of the frame body 1, and the engaging groove 18 and the floating preventing piece 17 are also so arranged. Since they are symmetrically arranged in correspondence with the above, the adjacent floor board members 4 and 4 which are exteriorly mounted can be joined by contacting any sides with each other. Therefore, when the grain has a prominent surname in the direction like the grain, it is possible to obtain various floor patterns by changing the direction of each floor board member 4 as desired.

The connecting tongue piece 13 has a locking projection 15 at the tip thereof, and the connecting hole 14 has a locking cross bar 16 inside thereof. When inserted, the former locking projection 15 is inserted while being elastically deformed and locked to the latter lateral locking bar 16, so that as shown in FIG. The frame bodies 1 and 1 can be connected to each other only by pressing them so as to abut. Further, it becomes difficult to bend the joining positions of the frame bodies 1 and 1 in the descending direction.

As shown in FIG. 9, the anti-floating member 17 also engages with the engaging groove 18 at the same time when the connecting tongue 13 and the connecting hole 14 are connected to each other, so that the floating preventing member 17 is prevented. Since the piece 17 is supposed to abut on the upper surface of the engaging groove 18, even if an attempt is made to pull up the corresponding joining position of the frame bodies 1 and 1, this cannot be easily done. The above-mentioned floating prevention piece 1
As for 7, 17, ..., If necessary, the rubber member 21 is arranged on the lower surface side (or not), then the screw 22 is fitted through the screw hole 19 on the upper side, and screwed into the floor base. You can also strengthen the fixation by.

Then, the floor plate materials 4, 4 ...
By arranging on the floor base while abutting the mutual sides while facing in a desired direction, the floor tensioning work can be easily performed. Also, after the installation is completed, the floor board materials 4, 4
Are the floating prevention pieces 17, the engagement grooves 18, and the coupling tongue pieces 1 of the frame body 1 which are respectively mounted on the outer peripheral portions 4b on the peripheral side.
3 and the connection holes 14 are connected, the floor plate members 4, 4
Even if an attempt is made to pull it up at the joint portion, it is not easily bent, and therefore cannot be levitated.

At a position adjacent to a corner or a pillar of a room, the floor plate 4 cannot be used as it is as a square when seen from a plane, but it can be freely cut even when the frame 1 is exteriorly mounted. It is possible to have a desired shape. Floor board material 4
The frame 1 and the frame 1 are connected by the screws 20, 20 ... Through the screw holes 7 of the connecting bases 6, 6 at a plurality of places, and the connection cannot be easily released even if some of the portions are cut off. Is.

When the floor is damaged due to long-term use and needs to be replaced, the floor board members 4, 4, ... 14 and the anti-floating piece 17 are connected by the engagement hole 18, and the floor base is only connected by the screw 22 fitted in the screw hole 19 of the anti-floating piece 17, and the whole is attached. Since it is not, it is easy to remove from the floor base. In particular, if a part of the floor plate material 4 is removed, the floor plate materials 4 adjacent to the floor plate material 4 can be easily removed in sequence. Therefore, the work of replacing the floor board members 4, 4, ... Can be performed extremely easily.

10 to 12 show a second embodiment of the present invention. The only difference from the first embodiment is the portion of the means for connecting the adjacent frame bodies 1, 1. The same reference numerals as those in the first embodiment indicate the same components and the same configurations.

Only the parts different from the first embodiment will be described. Coupling tongues 33 are formed so as to project from the central portions of the peripheral walls 3 and 3 on two adjacent sides of the frame body 1, and the coupling holes 34 corresponding to the coupling tongues 33 are formed on the peripheral walls 3 and 3 on the other two adjacent sides. Respectively. A locking projection 35 is formed at the tip of the coupling tongue 33 similarly to that of the first embodiment, and a locking lateral bar 36 similar to that of the first embodiment is formed inside the coupling hole 34.

Below the connecting holes 34, 34, as in the case of the first embodiment, the anti-floating pieces 37 are provided so as to project from the peripheral walls 3 and 3, respectively, and at the lower part of the connecting tongue 33. Are the engaging grooves 3 that engage with the floating prevention pieces 37, respectively.
Make up 8. Edge walls are erected on both sides of the floating prevention piece 37, and a screw hole 39 is formed in the central portion.

The above-mentioned second embodiment is exactly the same as the first embodiment except for the portion described as the above-mentioned different portion, is used almost in the same manner, and has the same effect. The difference is that the connection tongue piece 33, the connection hole 34, the floating prevention piece 37, and the engagement groove 38 are formed at the center of each side.
Therefore, there is only a restriction such that the sides of the adjacent frame bodies 1 and 1 that can be coupled to each other are the side having the coupling tongue 33 and the side having the coupling hole 34.

[0046]

According to the present invention, the work of stretching and removing the floor plate material is extremely easy, and as a result, the work of relining the floor plate material can be carried out very easily. It is also one that can reinforce floor boards. Most importantly, even if an attempt is made to pull up the adjacent mutual connection of the installed floorboards, it does not easily float in the form of bending upward.

[Brief description of drawings]

FIG. 1 is a plan view of a floor board material coupling frame according to a first embodiment.

FIG. 2 is a front view of the floor board material coupling frame of the first embodiment.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a perspective view of the floor board material of the first embodiment.

FIG. 6 is a perspective view of a leg member of the first embodiment.

FIG. 7 is a cross-sectional view of the floorboard material coupling frame in which the floorboard material and the leg members are set at the same position as in FIG. 3 in the first embodiment.

FIG. 8 is a cross-sectional view of the floorboard material coupling frame in which the floorboard material and the leg members are set at the same position as in FIG. 4 in the first embodiment.

FIG. 9 is an enlarged cross-sectional partial view showing a state in which the floor plate members and the leg members are connected to each other and adjacent floor plate member connecting frames in the first embodiment.

FIG. 10 is a plan view of a floor board material coupling frame according to a second embodiment.

FIG. 11 is a front view of the floor board material coupling frame of the second embodiment.

12 is a cross-sectional view taken along the line CC of FIG.

[Explanation of symbols]

 1 frame body 2 bottom plate 3 peripheral wall 4 floor board material 4a overhang 4b exterior part 5 reinforcing projection 6 coupling stand 7 screw hole 8 water-permeable hole 9 partitioning projection 10 leg hole 11 leg member 11a base 11b leg 12 locking collar 13 Coupling tongue 14 Coupling hole 15 Locking protrusion 16 Locking lateral bar 17 Lifting prevention piece 18 Engaging groove 19 Screw hole 20 Screw 21 Rubber member 22 Screw 33 Coupling tongue 34 Coupling hole 35 Locking protrusion 36 Locking horizontal bar 37 Floating prevention piece 38 Engagement groove 39 Screw hole

Claims (4)

[Claims] 1. A frame is constructed in the shape of a box consisting of a quadrilateral bottom plate and a peripheral wall rising from each side thereof, and the peripheral wall of the frame has a connecting tongue piece, a connecting hole, a floating preventing piece and an engaging member. A joint groove is formed, and the coupling hole is a hole into which a coupling tongue piece of a peripheral wall of another frame installed adjacently can be inserted, and the coupling tongue piece inserted therein is lowered downward. The engaging groove is a groove capable of engaging with the anti-floating piece of the peripheral wall of the other frame installed adjacent to the engaging groove. A floor board material connecting frame having a downward groove for preventing the lifted prevention piece from rising upward. 2. The floor board material connecting frame according to claim 1, wherein a plurality of reinforcing ridges, which double as a pedestal on which the floor board material is placed, are vertically and horizontally raised on the bottom plate. 3. The bottom plate is interspersed with a plurality of coupling bases raised to the same height as the reinforcing ridges, and each coupling base is provided with a screw hole penetrating through the front and back. Floor board connection frame. 4. The floor board material connecting frame according to claim 1, 2 or 3, wherein the floating preventing piece is formed in a plate shape in which edge walls are erected on both sides and a screw hole is formed near the center.