JPH08189074A - Grating - Google Patents

Abstract

PURPOSE: To improve strength by overlapping two pieces of thin-walled long members of substantially inverted U-shape cross section, providing plural cross- direction fit-in grooves in the longitudinal direction of the upper edge to form a cross bar, and combining main bars with the fit-in grooves from the longitudinal direction. CONSTITUTION: Both ends of vertically inverted main bars 1 are fitted in the locking grooves 31 of a pair of opposedly disposed jigs 30 and held in the parallel state. A connecting rod 3a is pressed downward from above into the recessed grooves 8 of the main bars 1 aligned in the orthogonal direction so as to fit the main bars 1 into cutout grooves 6a. A connecting rod is then fitted into the connecting rod 3a, and the connecting rod 3a and the other connecting rod is overlapped to fit the main bars 1 into the cutout grooves 6b, so that the connecting rod 3a and the other connecting rod form a cross bar 10. The cross-over parts of the main bars 1 and cross bar 10 are welded to form a grated frame, and side bars are jointed to both side edges. Since the connecting rods are doubled, strength can be improved, and cracking, cutting, and the like at fit-in groove parts can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grating used by being attached to a side groove or the like.

[0002]

2. Description of the Related Art In a grating a, as shown in FIG. 9, an appropriate number of long cross bars c are orthogonally arranged on a plurality of short main bars b arranged in parallel at predetermined intervals to form a grid frame d. There is a structure in which side bars e are arranged on both side edges along the longitudinal direction of the lattice frame d.

Such a conventional grating a is shown in FIG.
It is manufactured by the method shown in. First, as shown in FIG. 10 (a), each main bar b is provided with a connecting hole x and a cross bar c.
A plurality is formed corresponding to the number of. Here, the connection hole x is
The width of the cross bar c is greater than or equal to the vertical width of the cross bar c, and the vertical width thereof is less than that. Further, the stopper edges f are alternately provided above and below the center.

Further, as shown in FIG. 10B, a plurality of fitting grooves y are formed in the upper edge of the cross bar c at predetermined intervals corresponding to the number of main bars b.

Next, the main bars b are aligned at predetermined intervals by an appropriate jig, and as shown in FIG. 10 (c), the cross bars c are inserted sideways into the connecting holes x in a skewered shape. The fitting groove y of the cross bar c and the connecting hole x of the main bar b are opposed to each other, and then the cross bar c is rotated upward, and the side edge of the cross bar c abuts against the stopper edge f. The upper edge of each connecting hole x is fitted into.

Then, the crossbar c and the main bar b are welded to each other at the position of the connecting hole x to form a lattice frame d in which a plurality of main bars b and an appropriate number of crossbars c are orthogonal to each other. It

Next, as shown in FIG. 9, a grating a is manufactured by joining side bars e to both side edges along the longitudinal direction of the lattice frame d by welding.

[0008]

In the above-mentioned conventional grating a, it is necessary to form a complicated connecting hole x at each predetermined position of each main bar b constituting the lattice frame d. In addition, by inserting the crossbar c into the connecting hole x of each main bar b and rotating it upward, the upper end edge of the connecting hole x of each main bar b is simultaneously fitted into each fitting groove y of the crossbar c. The assembly was troublesome because it had to be done. Further, since the cross bar c is made of a square bar, there are drawbacks such as high production cost and heavy weight of the grating a.

Therefore, as shown in FIG. 12, the main bar 40 is orthogonal to the upper edge of the cross bar 41 made of a thin long material formed in a U-shaped cross section such as a U shape, a U shape, and a truncated circular shape. Forming a plurality of fitting insertion grooves 42 at predetermined intervals along the longitudinal direction, and inserting the main bars 40 into the respective fitting insertion grooves 42 from the vertical direction and combining them in a lattice shape. It has been proposed to construct a lattice frame by welding and joining the intersecting portions of the bar 40 and the crossbar 41.

With this structure, it is not necessary to form a connecting hole having a complicated shape in each main bar 40 as in the prior art, and it is easy to assemble the main bar 40 and the cross bar 41 in a grid pattern. There is an advantage that can be done.

By the way, such a configuration will be described later.
It has been found that when a large load is applied to the grating 40 and the whole is curved, the crossbar 41 is easily broken along the fitting insertion groove 42 and the strength is not sufficient. Therefore, as a reinforcing means thereof, as shown by a chain line in FIG. 12, a round bar 43 is provided parallel to the crossbar 41 on the lower surface of the grating.
It was arranged to reinforce by welding and fixing. However, with such means, the round bar 4
There was a big problem that the welding work of No. 3 became troublesome and the mass productivity was impaired. SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned conventional problems.

[0012]

SUMMARY OF THE INVENTION According to the present invention, a cross bar is formed into a U-shaped, U-shaped, or oval-shaped cross-section with a substantially U-shaped cross section, and a connecting rod made of a thin long member is formed inside and outside. Then, a plurality of transverse insertion grooves are provided at the upper edge thereof along the longitudinal direction at predetermined intervals, and a main bar is inserted into each insertion groove of the crossbar from the vertical direction to form a grid pattern. In addition, the above-mentioned lattice frame is assembled by welding and joining the intersecting portions of each main bar and the cross bar.

[0013]

The required number of main bars are turned upside down and aligned at a predetermined interval by an appropriate jig, and then the crossbar is turned downward and pushed down from above to insert the main bars into the respective fitting grooves. The bars can be fitted simultaneously. As a result, the main bar and the cross bar are combined in a grid pattern, and the necessary parts can be welded together to facilitate the assembly work. Here, since the crossbar is formed by two-piece polymerization of a connecting rod made of a thin long member formed in a substantially U-shaped cross section inside and outside, the strength is remarkably improved and a round bar etc. Does not require reinforcement. It is considered that this is because the elastic action of each connecting piece is maintained and the total thickness thereof is increased. The strength can also be improved when the total thickness of the two pieces is compared with a crossbar composed of a single connecting piece having the same thickness.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. Here, the grating 20 of the present invention is assembled in a lattice shape by a plurality of short main bars 1 formed in a T-shaped cross section and an appropriate number of long cross bars 10. The cross bar 10 is a connecting rod 3 made of a thin long member formed in a U-shaped cross section so as to have a U shape.
a and 3b are formed by polymerizing two pieces inside and outside. The connecting rods 3a and 3b may be sequentially polymerized when the main bar 1 is connected, or may be previously polymerized and then connected to the main bar 1. In addition, this connecting rod 3
The a and 3b are formed by means such as bending a strip-shaped thin plate.

The connecting rods 3a and 3b are different in width dimension, but have the same basic shape, and both left and right end edges 4 thereof.
a and 4b, a brim-shaped connecting portion 5a whose bottom edge is horizontally extended,
5b are provided respectively. Further, on the upper edge thereof, a plurality of cut grooves 6a, 6 in which the main bar 1 is fitted orthogonally are formed.
b is formed at predetermined intervals. Notch grooves 6a, 6b
The width of the main bar 1 is approximately the same as the thickness of the main bar 1, and the connecting rod 3
The connecting portions 5a and 5b are formed so as to extend to the vicinity of the lower end edges of a and 3b, and are vertically overlapped.

Then, the connecting rods 3a and 3b are overlapped with each other to form the crossbar 10, and the fitting grooves 11 are formed by aligning the cut grooves 6a and 6b.

The lower edge of the main bar 1 is fitted to the fitting groove 11 of the cross bar 10 when the cross bar 1 is fitted.
A concave groove 8 is formed corresponding to the position where the connecting portion 5a and the connecting portion 5b are accommodated so as to correspond to the position where the connecting portion 5 and 0 intersect.

The main bar 1 and the cross bar 10 are assembled in the following procedure. First, as shown in FIG. 4, the engaging groove 3 of the jigs 30, 30 (one side is omitted) provided on both sides so as to be opposed to each other so as to be positioned with respect to each other.
Both ends of the main bar 1 which is turned upside down are fitted into the respective units 1, and a plurality of main bars 1 are held by the jigs 30 and 30 and arranged in parallel.

Next, the connecting rods 3a are directed downward at the positions corresponding to the respective recessed grooves 8 of the main bar 1 aligned in the orthogonal direction and pushed down from above so that the main bars 1 are simultaneously fitted into the cut grooves 6a. . Similarly, the connecting rod 3b is fitted into the connecting rod 3a from above, the connecting rods 3a and 3b are overlapped, and the main bar 1 is fitted into the cut groove 6b. Then, in the fitted state, the crossbar 10 is constituted by the connecting rods 3a and 3b, and is assembled in a cross shape with the main bar 1 group.

The brim-shaped connecting portion 5 of the crossbar 10
By joining the intersections of a and 5b and the main bar 1 by spot welding, the main bar 1 and the cross bar 1
0 is fixed and the lattice frame 21 is configured. Here, since the main bar 1 and the cross bar 10 are joined by spot welding only to hold the general shape of the lattice frame 21, it is not necessary to weld all the intersecting parts, and several parts are required. It is enough to give it.

As shown in FIG. 5, the side bars 22 are joined to both side edges of the lattice frame 21 constructed as described above after the jigs 30, 30 are removed. Here, the jig 30,
Even if 30 is removed, each main bar 1 is held in an upright state by being fitted in the fitting groove 11 of the cross bar 10, and in this state, the side bar 22 is attached to the end of each main bar 1. By abutting and joining the abutting portions by gas welding or the like, the side bars 22 are joined to both side edges of the lattice frame 21 to complete the grating 20. The grating 20 is used in a state of being turned upside down.

In the crossbar 10, the brim-shaped connecting portions 5a and 5b formed on the lower end edges of the left and right side end edges 3 and 3, respectively.
Is provided so that spot welding can be easily performed from above, and if the side surfaces of the intersecting portions of the main bar 1 and the crossbar 10 are joined by gas welding or the like, the connecting portions 5a and 5b are It does not necessarily have to be a brim.

Further, the concave groove 8 formed at the lower edge of the main bar 1 for accommodating the connecting portions 5a and 5b of the crossbar 10 has the lower edge of the grating 20 flush with and stably supported by the receiving frame. Therefore, it is not necessary to form the concave groove 8 depending on the supporting mode.

FIG. 6 shows a structure of a crossbar 10 formed by superposing connecting rods 3a and 3b each having a U-shaped cross section and formed of a thin long member having a U-shaped cross section. The connecting rods 3a, 3b are provided with brim-shaped connecting portions 5a, 5b on both left and right end edges 4a, 4b of which lower end edges extend obliquely downward. Then, the connecting rods 3a and 3b are polymerized,
The cut grooves 6a and 6b are aligned with each other so that the fitting groove 1
Yields 1.

Further, the main bar 1 fitted in the fitting groove 11
On both sides of the concave groove 8, inclined surfaces 13, 13 are formed corresponding to the collar-shaped connecting portions 5a, 5b. When the upper edge of the crossbar 10 is curved as described above, it is possible to obtain an effect that dust and the like attached to the upper edge are easily washed away by the drainage flowing from the upper portion of the grating 20 into the side groove. Also, the same guiding action can be obtained by the brim-shaped connecting portions 5a and 5b extending obliquely downward. Although not shown,
In addition to the above, the cross bar 10 may be a thin long member having a substantially U-shaped cross section, which exhibits a V shape, a rhombus shape, or the like.

FIG. 7 shows a third embodiment of a crossbar 10 formed in a cross-sectional shape slightly different from that of FIG. 6, in which the connecting rods 3a, 3b made of a thin long member have a substantially circular cross-section U having a cutout shape. This is polymerized by using what is formed into a shape.

FIG. 8 shows a crossbar 10 with a collar-shaped connecting portion 5a,
A fourth embodiment of a crossbar 10 formed by superimposing connecting rods 3a and 3b that do not form 5b is shown. The upper end of a thin long member formed in a U-shaped cross section to have a U-shape, The cut grooves 6a and 6b are formed at predetermined intervals along the longitudinal direction, and the lower edges of the cut grooves 6a and 6b are connected to the connecting portion 5.
a and 5b. Further, the concave groove 8 of the main bar 1 for accommodating the connecting portions 5a and 5b is also deeply formed corresponding to the vertical width of the connecting portions 5a and 5b. The fitting groove 11 is formed by the cut grooves 6a and 6b.

In each of the above embodiments, the main bar 1 has a T-shaped cross section, but the present invention can also be applied to a main bar having a rectangular or inverted L-shaped cross section.

In the above structure, since the crossbar 10 is constructed by stacking the two connecting rods 3a and 3b on the inside and the outside, the thickness of the crossbar 10 is not impaired by the connecting rods 3a and 3b. Can be increased, and thus the strength is dramatically improved.

Here, FIG. 11 is a graph showing the result of the compression test, and (a) relates to the configuration shown in FIG. (B) relates to a configuration in which a cross bar 41 consisting of a single connecting rod shown in FIG. 12 is used, and a round bar 43 is joined and reinforced in order to reinforce the configuration. (C) relates to the configuration of FIG. 12 in which the round bar 43 is not used. (D) uses the crossbar 41 which is composed of a single connecting rod having the same thickness as the total thickness of the connecting rods 3a and 3b in FIG. As shown in each of these experiments, the invention of
22,000N (Newton), B) 21,500N, Ha)
14,000N, 2) 18,000N, crossbar 1 each
0 broke.

From this, it is understood that the structure of the present invention has the highest strength. On the other hand, the configuration of FIG. 12 is slightly inferior in strength to the present invention, and since the round bar 43 has to be joined, the assembly is troublesome, and therefore the present invention is obviously superior. It is understood that
When the single connecting rod 3a of (c) is used, the strength is of course low. When a single connecting rod 3a having the same thickness as that of the present invention is formed, the elasticity is reduced, and therefore, when a large load is applied, the plastic deformation does not return to the original state and the crushing occurs. It bends easily and the strength as in the present invention cannot be obtained. In addition, since the wall thickness is large, a large load is required for bending and the molding becomes troublesome.

[0032]

As described above, according to the present invention, the connecting rods 3a and 3b, which are the connecting rods 3a and 3b, which are made of a thin long member having a substantially U-shaped cross section.
Since the crossbar 10 is formed by stacking two pieces inside and outside, high strength can be obtained, and the grating 20
Even if a large load is applied to the upper part, cracks and cuts do not occur along the fitting groove 11, and the highly reliable grating 20 can be configured, and at the same time, a reinforcing material such as a round bar. It is possible to avoid the complexity of processing such as the configuration of joining the parts, and to further improve the ease of assembling the grating 20 using the crossbar 10 including the fitting groove 11 and other excellent effects. is there.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention in a separated state.

FIG. 2 is a side sectional view of the above-mentioned separated state.

FIG. 3 is a side sectional view of the assembling state of the above.

FIG. 4 is a perspective view showing an assembling process of the above.

FIG. 5 is a bottom view of a lattice frame 21 constructed by assembling the main bar 1 and the cross bar 10 above.

FIG. 6 is a side sectional view showing an assembled state of the second embodiment of the present invention.

FIG. 7 is a side sectional view of an assembled state of the third embodiment of the present invention.

FIG. 8 is a side sectional view showing an assembled state of a fourth embodiment of the present invention.

FIG. 9 is a plan view of a conventional grating a.

FIG. 10 is a side view of a configuration of a main part of a conventional grating a and a perspective view showing an assembling method.

FIG. 11 is a graph showing the results of compression tests of various configurations.

FIG. 12 is a vertical cross-sectional side view showing a main part of a prior art grating 40.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 main bar 3a, 3b connecting rod 5a, 5b connecting part 6a, 6b cutting groove 8 concave groove 10 crossbar 11 fitting insertion groove 20 grating 21 lattice frame

Claims (1)

[Claims] 1. A grating having a lattice frame composed of a plurality of main bars arranged in parallel at predetermined intervals and a cross bar extending orthogonally to each main bar, wherein the cross bars are U-shaped and U-shaped. , A connecting rod made of a thin-walled long material formed into a generally U-shaped cross section such as a truncated circle is superposed on the inside and outside, and a plurality of transverse fitting grooves are provided along the longitudinal direction at its upper edge at predetermined intervals. Each main bar is inserted into each fitting groove of the cross bar from the vertical direction and combined in a lattice shape, and the intersections of each main bar and the cross bar are welded and joined together. A grating having the lattice frame assembled therein.