CA1182976A - Floor grating - Google Patents
Floor gratingInfo
- Publication number
- CA1182976A CA1182976A CA000389626A CA389626A CA1182976A CA 1182976 A CA1182976 A CA 1182976A CA 000389626 A CA000389626 A CA 000389626A CA 389626 A CA389626 A CA 389626A CA 1182976 A CA1182976 A CA 1182976A
- Authority
- CA
- Canada
- Prior art keywords
- bars
- slots
- longitudinal bars
- longitudinal
- transverse
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Sewage (AREA)
Abstract
ABSTRACT
The invention discloses a method of forming gratings suitable for use as walkways etc. The method includes the steps of forming transverse bearer bars from strips of flat plate by punching a series of transverse slots across the cental axis of each plate, then folding the plates to form U-sections with the slots located in the apices of the U-sections. Longitudinal bars, which are lengths of flat bar, are then inserted as tight press-fits into the slots, and the undersides of the longitudinal bars are deformed laterally between the legs of each U-section to prevent their removal from the slots. A strong lightweight grating results.
The invention discloses a method of forming gratings suitable for use as walkways etc. The method includes the steps of forming transverse bearer bars from strips of flat plate by punching a series of transverse slots across the cental axis of each plate, then folding the plates to form U-sections with the slots located in the apices of the U-sections. Longitudinal bars, which are lengths of flat bar, are then inserted as tight press-fits into the slots, and the undersides of the longitudinal bars are deformed laterally between the legs of each U-section to prevent their removal from the slots. A strong lightweight grating results.
Description
- 2 -FIELD OF THE ~NVENTION
THIS invention relates to a method for fornling f'loor gratings which are suitable for supportinq substantial loads ofF the grounds and to gratings formed by the method. In particular~ the invention relates to gratings of the type having two sets of parallel bars extending at right angles S to one another to form a load supporting grid arrangement. Such gratings are commonly used in eleva-ted walkways etc.
In this specification, the two sets of bars will be referred to as longitudinal and transverse bars respectively, but this is not to be taken in any way as 'limîting the direction in which either set may extend in an assembled grating.
BACKGROUND TO THE INVENTION
It has already been proposed to use inverted U-shaped members for the transverse bars (see United States Patent No. 1,620,846 to A.E. Wells), with slots being cut in the apices of these members to receive portions of the longitudinal bars. In United States Patent No. 1,620,846, the preferred shape of the longitudinal bars is a square section. According to that patent, once a series of transverse bars have been arranged in parallel with their slots aligned, the longitudinal bars are dropped loosely into the slots to form a grid. Tlle 510ts are made deep enough to receive the full height of the 10ngitudinal bars.
Once in position in the slots, the longitudinal bars are deformed outwardly in those regions lying between the legs of the U-shaped transverse bars to prevent their removal from the slots. The transverse bars are also deformed above the 'longitudinal bars to provide further insurance against withdrawal from the slots.
There are a number of problems associated with the manufacture of a grating 25 of the type disc'losed in USP 1,620,846. In this patent, the inverted .- ~ .
THIS invention relates to a method for fornling f'loor gratings which are suitable for supportinq substantial loads ofF the grounds and to gratings formed by the method. In particular~ the invention relates to gratings of the type having two sets of parallel bars extending at right angles S to one another to form a load supporting grid arrangement. Such gratings are commonly used in eleva-ted walkways etc.
In this specification, the two sets of bars will be referred to as longitudinal and transverse bars respectively, but this is not to be taken in any way as 'limîting the direction in which either set may extend in an assembled grating.
BACKGROUND TO THE INVENTION
It has already been proposed to use inverted U-shaped members for the transverse bars (see United States Patent No. 1,620,846 to A.E. Wells), with slots being cut in the apices of these members to receive portions of the longitudinal bars. In United States Patent No. 1,620,846, the preferred shape of the longitudinal bars is a square section. According to that patent, once a series of transverse bars have been arranged in parallel with their slots aligned, the longitudinal bars are dropped loosely into the slots to form a grid. Tlle 510ts are made deep enough to receive the full height of the 10ngitudinal bars.
Once in position in the slots, the longitudinal bars are deformed outwardly in those regions lying between the legs of the U-shaped transverse bars to prevent their removal from the slots. The transverse bars are also deformed above the 'longitudinal bars to provide further insurance against withdrawal from the slots.
There are a number of problems associated with the manufacture of a grating 25 of the type disc'losed in USP 1,620,846. In this patent, the inverted .- ~ .
- 3 --U-shaped melllbers are formed by forcing the legs of an angle section member toward one another. In view of the substantial strength o-f most standard angle sections available, this operation is not easily achieved.
The diFficulty is increased in that standard angle sections have a finite radius in the fillet of the section which provides some resistance to bending the legs of the section towards one another.
Another problem is encountered in the provision o-f the slots in the apices of the transverse members. It is suggested in USP 1,620,~6 that this be achieved by a lateral punching operation, or by cutting. It will be appreciated that the fillet of the angle section will provide resistance to this operation as well. The very nature of the angle section renders the punching operation at the apex a difficult one.
Deformation of the longitudinal bars is achieved by means of a pressing operation. The bed plate of the press used is shaped to deform the transverse bars in the region of the edges of the slots to cause these edges to overlap the longitudinal bars which have been received in the slots. Such deformation has the effect of reducing the compressive strength ~f the upper edges of the transverse bars. Furthermore, the fact that the whole depth of the longitudinal bars is received within the slots formed in the transverse bars means that the uppermost edges of the steel of the transverse bars are unable to take any compressive loading at all, since there is no continuity of material above the level of the longitudinal bars.
A further disadvantage of the grating described in US-PS 19~20,846 lies in the protection of the grating against corrosion once it has been fabricated. Sharp bends etc. should be avoided if galvanising or painting operations are contemplated,to ensure that a uniform coating is achieved. The deformation employed in the grating shown in the US
specification will give rise to sharp edges at the sides of the slots, and consequently to difficulty in applying the necessary coating to these critical areas of the steel to protect it.
Nevertheless, the use of U-shaped transverse members has been shown 7~
-to have cextain advantages as regards weight savings. It is accordingly an object of the present inven-tion to pro-vide a method of manufacture for a grating employiny such members, which method does not suffer from the disad-vantayes set ou-t above in respect of the kno~n gratings.
SUMMARY OF THE INVENTION
~` The invention provides a method of Eorming a floor grating having a plurality of longitudinal bars including the s-teps of punching slots in flat plates, folding the flat plates to produce transverse bars ; having an inverted U-shape wlth the punched slots forming slots in the apices of the transverse bars, securing longitudinal bars in the slots in the apices ii of the transverse bars by deforming them in those regions lying within the U~shapes, without cutting the material of the longitudinal bars, so that the depth of the longi-tudinal bars is substantially the same in those regions within the U-shapes as in those regions lying outside the U-shapes.
Preferably, the longitudinal bars are press-; fitted into the slots.
The slots may be formed in the apices of thetransverse bars by punching prior to folding the flat ` plate.
The longitudinal bars may be deformed by applying a lateral force to the material of each longitudinal bar in those reg:ions lying within the U-shapes to produce a bulge on one side of the plane of the longitudinal bar.
Conveniently, adjacent longitudinal bars in each U~snape are deformed simultaneously by forcing - 4a -' ~ .
:~ .
between them a pressing head havlng an operative width greater than the clear spacing between the longitudinal bars.
Another aspect of the invention provides a floor grating having a plurallty of -transverse bars and a plurality of longitudinal bars, with the transverse bars being folded from flat ma-terial to produce an . inverted U--shape and the longitudinal bars beincJ secured in slots in the api.ces ~ .
, . , .
~ 20 ' ' ~;
' 30 .~ .
- 4b - !
~' ~' o~ the transverse bars hy deformation, w;thoLJt cutting, of t~los~ r~gions of the longitudinal bars lying within the U-shapes, the deform~tioll being such that the depth o~ the longitudinaI bars is substantially the same in those regions lying wi-thin the U-shapes as in those regions lying outside the U-shapes.
PreferablY, a portion of each 14ngitudinal bar projects above the level of the apices of` the transverse bars.
To ensure a better foot~old for a person using the grating, those T)ortions of the 10ngitudinal bars projecting above the level of the apices of the transverse bars may be notched.
To reduce the likelihood ofparticula~e material jan~ing in the gaps between the transverse bars, it is preferred that the legs of each U-shaped transverse bar are substantially parallel to each other.
BRIEF ~ESCRIPTION OF THE DRAWINGS
The invention will now be ~urther described, by way of example, with 15 reference to the accompany;ng drawing, in which Figure 1 is a perspective view of a grating according to the invention;
Figure 2 is an underneath view of the grating shown in Figure l; and Figure 3 is a side view of the grating shown in Figure 1.
Figure 4 shows a plan view of a plate after a punch;ng operation to ~orm slots across the central axis, and, Figure 5 shows a section of a transverse bar after punching and folding along the central axis9 and a longitudinal bar castellated along its upper edge prior to insertion in a slot in the trans~crse bar.
DESCRIPTION OF A PREFERRED EMBODIMENT
_ __ . _ The sectio~ of finished grating shown in Figure 1 is made up o~ transverse bearer bars 1 and longitudinal bars 2. Each transverse bearer bar hasa U-shaped cross-section, a~ can be most clearly seen in Figures 3 and 5.
The U-shape in fact approximates to a V-shapeg but in practice there will always be some radius at the apex of the section, and the section is accordingly described as U-shape. Furthermore, it is preferred to have a slightly rounded apex, for it will be appreciated that it could be uncomfortable on the feet of a person walking over the grating if the apices of the transYerse bearer bars are too sharply pointed.
73l j It will also be seen in the drawings that the longitudinal bars 2 have castellated upper edges. This serves as an aid in the prevention of slippage on the grating. It will be appreciated that gratings of the type under consideration are often used at substantial elevations, and that slippage of a person walking over the gra-ting could have disasterous consequences.
The transverse bearer bars l are formed in the ~ollowir)g manner:
Strips of flat plate are passed beneath a punch, which is operated to punch a series of spaced transverse slots 5 frorn the plates across their central axes. One such plate is illustrated in Figure 4 after the punch-ing operation.
The plates are then folded to the shape shown in Figure 5 about the central ax1s. The resulting U-section then has a series of spaced slots 5 located along its apex.
The transverse bearer bars l are then arranged in a spaced parall~l relationship with the corresponding slots in each bar directed upwardly and in alignment with one another, ready to receive longitudinal bars 2 to form the grating.
The longitudinal bars 2 are lengths of ~lat bar. The bars 2, prior to their insertion into the slots, are castellated along their upper edges to provide a better foothold for persons using the grating.
.
Each longitudinal bar 2 is then forced as a tight press-fit into one row of aligned slots. It should be noted that,the dimensions of the slots are such that when the plate has been folded to produce the trans-verse bearer bars, the depth of the slots is not sufficient to receivethe full depth of the longitudinal bars. The castellated portion of each longitudinal bar protrudes above the level of the apices of the transverse bars, as can clearly be seen in Figure 3. As the longitudinal bars are forced into the slots in the transverse bars, the tightness of the fit may result in the upper edge of the steel of the transverse bars being subjected to compression, i.e. a "prestressing"
of these upper edges takes place at the region indicated as 3. A slight bowing of the transverse bars may even take place. It will be appreciated that this acts to increase the overall strength of the assembled grating. When compared to the grating disclosed in US patent No. 1,620,846, it will be seen that the continuity of ma-terial at the level of the apices of the transverse bars in the present invention makes for greater strength in compression along the upper edges of the transverse bars than does the lack of continuity of material in the earlier disclosure.
Once all the longitudinal bars have been forced into their slots, the undersides of these bars are deformed to prevent their withdrawal from the slots. Referring to Figure 2, it will be seen that the longitudinal bars are deformed by E~rmin~ a ~idewa~s b-~lge 4. In practice, a single pressing head having an operative thickness greater than the spacing of the longitudinal bars is caused to act between the two adjacent longitudinal bars of a pair in the space between the legs of each U-section to cause the bars to bulge in opposite directions. In ; view of the rapidity and simplicity of the deforming operation, it is desirable to deform the longitudinal bars in the region between the legs of each transverse bearer bar~ so as to provide greater rigidity to the whole structure.
It has been found that gratings manufactured according to the method of the present invention have a weight some 30% less than comparable gratings which exhibit similar strength. This is mainly due to the method of formation of the transverse bearer bars. It has been found that a suitable thickness of plate for use in preparing the transverse ~5 bearPr bars is 3mm for r~st appl;cations. Such plate is not excessive in weight~ and is easily punched and handled.
In practice, it has been found necessary in some applications to -fold the legs of the transverse bars into almost parallel alignment with one another. This c~nfiguration allows lumps of coal etc. to fall freely between the transverse bars without becoming jammed~ It will be appreciated that this would be difficult to achieve if the transverse bearer bars were formed from angle section steel as suggested in US
patent No. 1,620,846, in view of the difficulty in bending the legs of the angle towards one another.
" , 7~i The grating described also allows Eor a better protectlve coating to be applied to the finished grating than does the grating of the U.S. Patent The fact that no complex crimping operations take place along the apices of the transverse bars, with no result:irlg sharp edges, allows for greater uniformity of coating o~, say zinc, in a galvanising process. The tight:ness oE the fit in the slo-ts also acts to lessen -the likelihood of relatlve movement between the two sets oE bars, wi-th less resulting abrasion between bars and des-truction of a coating which has been applied.
A further, readily ascer-tainable advantage of the method of the present inven-tion over the disclosure of -the United States Pa-tent lies ln the punching operation to form the slots in the apices of the transverse bars.
It will be appreciated that it is easier to punch slots from a flat plate than it is to punch or cut the slot laterally from -the apex of a steel angle section.
Furthermore, the present inven-tion is applicable to grating intended for almost any spanO With steel sections, the designer is limited by the angle sec-tions available. ~ith increasing angle size, there will be increasing fabrication difficul-ties. Gra-tings formed according to the present invention can be designed to suit a wide range of spans, by, for example, increasing or decreasing -the length of the legs of the transverse bars, as the case may be.
Having described wha-t is believed to be the bes-t mode by which the invention may be performed, it will be seen -that the invention may be particularly defined as ~, , '.
follows:
A method of forming a fl.oor gra-ting having a plurality of longitudinal bars including the steps of punching slots in flat plates, folding the flat plates to produce transverse bars having an inverted U-shape with the punched slots forming slots in the ap:ices of the transverse bars, securing longi-tudinal bars in the : slots ln the apices of the transverse bars by deforming them in those regions lying within the U shapes, w.ithout cutting the material of the longi-tudinal bars, so -that the depth of the longitudinal bars is substantial.ly the same in those regions within the U-shapes as in those regions lying outside the U-shapes.
The invention further comprises a floor grating having a plurality of transverse bars and a plu~ality of lon~itudinal bars, with the transverse bars being folded from the flat material to produce an inver-ted U-shape and the longitudinal bars being secured in slots in the apices of the transverse bars by deformation, without cutting, -of those reyions of the longitudinal baxs lying within the U-shapes, the defo.rmation being such that the dep-th of the longitudinal bars is substantially the same in those regions lying within the U-shapes as in those regions lyin~ outside the U-shapes.
: The foregoing is a description of a preferred embodiment of the invention which is given here by way of example only. The invention is not to be taken as limited to any of the specific features as described, but compre-hends all such variations thereo$ as come within the scope of the appended claims.
,' _ 9 _ ;
The diFficulty is increased in that standard angle sections have a finite radius in the fillet of the section which provides some resistance to bending the legs of the section towards one another.
Another problem is encountered in the provision o-f the slots in the apices of the transverse members. It is suggested in USP 1,620,~6 that this be achieved by a lateral punching operation, or by cutting. It will be appreciated that the fillet of the angle section will provide resistance to this operation as well. The very nature of the angle section renders the punching operation at the apex a difficult one.
Deformation of the longitudinal bars is achieved by means of a pressing operation. The bed plate of the press used is shaped to deform the transverse bars in the region of the edges of the slots to cause these edges to overlap the longitudinal bars which have been received in the slots. Such deformation has the effect of reducing the compressive strength ~f the upper edges of the transverse bars. Furthermore, the fact that the whole depth of the longitudinal bars is received within the slots formed in the transverse bars means that the uppermost edges of the steel of the transverse bars are unable to take any compressive loading at all, since there is no continuity of material above the level of the longitudinal bars.
A further disadvantage of the grating described in US-PS 19~20,846 lies in the protection of the grating against corrosion once it has been fabricated. Sharp bends etc. should be avoided if galvanising or painting operations are contemplated,to ensure that a uniform coating is achieved. The deformation employed in the grating shown in the US
specification will give rise to sharp edges at the sides of the slots, and consequently to difficulty in applying the necessary coating to these critical areas of the steel to protect it.
Nevertheless, the use of U-shaped transverse members has been shown 7~
-to have cextain advantages as regards weight savings. It is accordingly an object of the present inven-tion to pro-vide a method of manufacture for a grating employiny such members, which method does not suffer from the disad-vantayes set ou-t above in respect of the kno~n gratings.
SUMMARY OF THE INVENTION
~` The invention provides a method of Eorming a floor grating having a plurality of longitudinal bars including the s-teps of punching slots in flat plates, folding the flat plates to produce transverse bars ; having an inverted U-shape wlth the punched slots forming slots in the apices of the transverse bars, securing longitudinal bars in the slots in the apices ii of the transverse bars by deforming them in those regions lying within the U~shapes, without cutting the material of the longitudinal bars, so that the depth of the longi-tudinal bars is substantially the same in those regions within the U-shapes as in those regions lying outside the U-shapes.
Preferably, the longitudinal bars are press-; fitted into the slots.
The slots may be formed in the apices of thetransverse bars by punching prior to folding the flat ` plate.
The longitudinal bars may be deformed by applying a lateral force to the material of each longitudinal bar in those reg:ions lying within the U-shapes to produce a bulge on one side of the plane of the longitudinal bar.
Conveniently, adjacent longitudinal bars in each U~snape are deformed simultaneously by forcing - 4a -' ~ .
:~ .
between them a pressing head havlng an operative width greater than the clear spacing between the longitudinal bars.
Another aspect of the invention provides a floor grating having a plurallty of -transverse bars and a plurality of longitudinal bars, with the transverse bars being folded from flat ma-terial to produce an . inverted U--shape and the longitudinal bars beincJ secured in slots in the api.ces ~ .
, . , .
~ 20 ' ' ~;
' 30 .~ .
- 4b - !
~' ~' o~ the transverse bars hy deformation, w;thoLJt cutting, of t~los~ r~gions of the longitudinal bars lying within the U-shapes, the deform~tioll being such that the depth o~ the longitudinaI bars is substantially the same in those regions lying wi-thin the U-shapes as in those regions lying outside the U-shapes.
PreferablY, a portion of each 14ngitudinal bar projects above the level of the apices of` the transverse bars.
To ensure a better foot~old for a person using the grating, those T)ortions of the 10ngitudinal bars projecting above the level of the apices of the transverse bars may be notched.
To reduce the likelihood ofparticula~e material jan~ing in the gaps between the transverse bars, it is preferred that the legs of each U-shaped transverse bar are substantially parallel to each other.
BRIEF ~ESCRIPTION OF THE DRAWINGS
The invention will now be ~urther described, by way of example, with 15 reference to the accompany;ng drawing, in which Figure 1 is a perspective view of a grating according to the invention;
Figure 2 is an underneath view of the grating shown in Figure l; and Figure 3 is a side view of the grating shown in Figure 1.
Figure 4 shows a plan view of a plate after a punch;ng operation to ~orm slots across the central axis, and, Figure 5 shows a section of a transverse bar after punching and folding along the central axis9 and a longitudinal bar castellated along its upper edge prior to insertion in a slot in the trans~crse bar.
DESCRIPTION OF A PREFERRED EMBODIMENT
_ __ . _ The sectio~ of finished grating shown in Figure 1 is made up o~ transverse bearer bars 1 and longitudinal bars 2. Each transverse bearer bar hasa U-shaped cross-section, a~ can be most clearly seen in Figures 3 and 5.
The U-shape in fact approximates to a V-shapeg but in practice there will always be some radius at the apex of the section, and the section is accordingly described as U-shape. Furthermore, it is preferred to have a slightly rounded apex, for it will be appreciated that it could be uncomfortable on the feet of a person walking over the grating if the apices of the transYerse bearer bars are too sharply pointed.
73l j It will also be seen in the drawings that the longitudinal bars 2 have castellated upper edges. This serves as an aid in the prevention of slippage on the grating. It will be appreciated that gratings of the type under consideration are often used at substantial elevations, and that slippage of a person walking over the gra-ting could have disasterous consequences.
The transverse bearer bars l are formed in the ~ollowir)g manner:
Strips of flat plate are passed beneath a punch, which is operated to punch a series of spaced transverse slots 5 frorn the plates across their central axes. One such plate is illustrated in Figure 4 after the punch-ing operation.
The plates are then folded to the shape shown in Figure 5 about the central ax1s. The resulting U-section then has a series of spaced slots 5 located along its apex.
The transverse bearer bars l are then arranged in a spaced parall~l relationship with the corresponding slots in each bar directed upwardly and in alignment with one another, ready to receive longitudinal bars 2 to form the grating.
The longitudinal bars 2 are lengths of ~lat bar. The bars 2, prior to their insertion into the slots, are castellated along their upper edges to provide a better foothold for persons using the grating.
.
Each longitudinal bar 2 is then forced as a tight press-fit into one row of aligned slots. It should be noted that,the dimensions of the slots are such that when the plate has been folded to produce the trans-verse bearer bars, the depth of the slots is not sufficient to receivethe full depth of the longitudinal bars. The castellated portion of each longitudinal bar protrudes above the level of the apices of the transverse bars, as can clearly be seen in Figure 3. As the longitudinal bars are forced into the slots in the transverse bars, the tightness of the fit may result in the upper edge of the steel of the transverse bars being subjected to compression, i.e. a "prestressing"
of these upper edges takes place at the region indicated as 3. A slight bowing of the transverse bars may even take place. It will be appreciated that this acts to increase the overall strength of the assembled grating. When compared to the grating disclosed in US patent No. 1,620,846, it will be seen that the continuity of ma-terial at the level of the apices of the transverse bars in the present invention makes for greater strength in compression along the upper edges of the transverse bars than does the lack of continuity of material in the earlier disclosure.
Once all the longitudinal bars have been forced into their slots, the undersides of these bars are deformed to prevent their withdrawal from the slots. Referring to Figure 2, it will be seen that the longitudinal bars are deformed by E~rmin~ a ~idewa~s b-~lge 4. In practice, a single pressing head having an operative thickness greater than the spacing of the longitudinal bars is caused to act between the two adjacent longitudinal bars of a pair in the space between the legs of each U-section to cause the bars to bulge in opposite directions. In ; view of the rapidity and simplicity of the deforming operation, it is desirable to deform the longitudinal bars in the region between the legs of each transverse bearer bar~ so as to provide greater rigidity to the whole structure.
It has been found that gratings manufactured according to the method of the present invention have a weight some 30% less than comparable gratings which exhibit similar strength. This is mainly due to the method of formation of the transverse bearer bars. It has been found that a suitable thickness of plate for use in preparing the transverse ~5 bearPr bars is 3mm for r~st appl;cations. Such plate is not excessive in weight~ and is easily punched and handled.
In practice, it has been found necessary in some applications to -fold the legs of the transverse bars into almost parallel alignment with one another. This c~nfiguration allows lumps of coal etc. to fall freely between the transverse bars without becoming jammed~ It will be appreciated that this would be difficult to achieve if the transverse bearer bars were formed from angle section steel as suggested in US
patent No. 1,620,846, in view of the difficulty in bending the legs of the angle towards one another.
" , 7~i The grating described also allows Eor a better protectlve coating to be applied to the finished grating than does the grating of the U.S. Patent The fact that no complex crimping operations take place along the apices of the transverse bars, with no result:irlg sharp edges, allows for greater uniformity of coating o~, say zinc, in a galvanising process. The tight:ness oE the fit in the slo-ts also acts to lessen -the likelihood of relatlve movement between the two sets oE bars, wi-th less resulting abrasion between bars and des-truction of a coating which has been applied.
A further, readily ascer-tainable advantage of the method of the present inven-tion over the disclosure of -the United States Pa-tent lies ln the punching operation to form the slots in the apices of the transverse bars.
It will be appreciated that it is easier to punch slots from a flat plate than it is to punch or cut the slot laterally from -the apex of a steel angle section.
Furthermore, the present inven-tion is applicable to grating intended for almost any spanO With steel sections, the designer is limited by the angle sec-tions available. ~ith increasing angle size, there will be increasing fabrication difficul-ties. Gra-tings formed according to the present invention can be designed to suit a wide range of spans, by, for example, increasing or decreasing -the length of the legs of the transverse bars, as the case may be.
Having described wha-t is believed to be the bes-t mode by which the invention may be performed, it will be seen -that the invention may be particularly defined as ~, , '.
follows:
A method of forming a fl.oor gra-ting having a plurality of longitudinal bars including the steps of punching slots in flat plates, folding the flat plates to produce transverse bars having an inverted U-shape with the punched slots forming slots in the ap:ices of the transverse bars, securing longi-tudinal bars in the : slots ln the apices of the transverse bars by deforming them in those regions lying within the U shapes, w.ithout cutting the material of the longi-tudinal bars, so -that the depth of the longitudinal bars is substantial.ly the same in those regions within the U-shapes as in those regions lying outside the U-shapes.
The invention further comprises a floor grating having a plurality of transverse bars and a plu~ality of lon~itudinal bars, with the transverse bars being folded from the flat material to produce an inver-ted U-shape and the longitudinal bars being secured in slots in the apices of the transverse bars by deformation, without cutting, -of those reyions of the longitudinal baxs lying within the U-shapes, the defo.rmation being such that the dep-th of the longitudinal bars is substantially the same in those regions lying within the U-shapes as in those regions lyin~ outside the U-shapes.
: The foregoing is a description of a preferred embodiment of the invention which is given here by way of example only. The invention is not to be taken as limited to any of the specific features as described, but compre-hends all such variations thereo$ as come within the scope of the appended claims.
,' _ 9 _ ;
Claims (10)
1. A method of forming a floor grating having a plurality of longitudinal bars including the steps of punching slots in flat plates, folding the flat plates to produce transverse bars having an inverted U-shape with the punched slots forming slots in the apices of the traverse bars, securing longitudinal bars in the slots in the apices of the transverse bars by deforming them in those regions lying within the U-shapes, without cutting the material of the longitudinal bars, so that the depth of the longitudinal bars is substantially the same in those regions within the U-shapes as in those regions lying outside the U-shapes.
2. A method according to Claim 1, in which the longitudinal bars are press-fitted into the slots.
3. A method according to Claim 1, in which the longitudinal bars are deformed by applying a lateral force to the material of each longitudinal bar in those regions lying within the U-shapes to produce a bulge on one side of the plane of the longitudinal bar.
4. A method according to Claim 3, in which adjacent longitudinal bars in each U-shape are deformed simul-taneously by forcing between them a pressing head having an operative width greater than the clear spacing between the longitudinal bars.
5. A method according to Claim 1, in which the slots are formed so that a portion of the longitudinal bars projects above the level of the apices of the transverse bars when the longitudinal bars are received in the slots.
6. A floor grating having a plurality of transverse bars and a plurality of longitudinal bars, with the transverse bars being folded from the flat material to produce an inverted U-shape and the longitudinal bars being secured in slots in the apices of the transverse bars by deformation, without cutting, of those regions of the longitudinal bars lying within the U-shapes, the deformation being such that the depth of the longi-tudinal bars is substantially the same in those regions lying within the U shapes as in those regions lying outside the U-shapes.
7. A grating according to Claim 6, in which the longitudinal bars are a press-fit in the slots,
8. A grating according to Claim 6, in which the longitudinal bars each have bulges formed in them on one side of their plane in those regions lying within the U-shapes.
9. A grating according to Claim 8, in which pairs of adjacent longitudinal bars have oppositely directed bulges formed by a single pressing operation.
10. A grating according to Claim 6, in which a portion of each longitudinal bar projects above the level of the apices of the transverse bars.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000389626A CA1182976A (en) | 1981-11-06 | 1981-11-06 | Floor grating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000389626A CA1182976A (en) | 1981-11-06 | 1981-11-06 | Floor grating |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1182976A true CA1182976A (en) | 1985-02-26 |
Family
ID=4121352
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000389626A Expired CA1182976A (en) | 1981-11-06 | 1981-11-06 | Floor grating |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1182976A (en) |
-
1981
- 1981-11-06 CA CA000389626A patent/CA1182976A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4485606A (en) | Truss structures constructed with metal web members | |
| AT4010U1 (en) | SKI, WHICH IS EQUIPPED WITH AN INTERMEDIATE DEVICE FOR WEARING THE HOLDING ELEMENTS OF THE SHOE | |
| WO2006123176A9 (en) | Slab load transfer plate | |
| KR880010998A (en) | Wire conveyor belt | |
| US4475328A (en) | Web member | |
| KR101890275B1 (en) | Truss girder rebar assembly with space coupler and construction method of deep deck using of the same | |
| US4348850A (en) | Web member | |
| KR101933661B1 (en) | Indexing tab for grid runner | |
| CA1182976A (en) | Floor grating | |
| EP0051445B1 (en) | A floor grating | |
| EP0181854A2 (en) | Connector plate for the fabrication of composite beams | |
| US3948013A (en) | Cold forged steel grating | |
| CA1057018A (en) | Metal grating | |
| US5661993A (en) | Punch tool and method for manufacturing truss plates | |
| US9212504B1 (en) | Fence post system, construction, and method | |
| CA2282109C (en) | Apparatus for creating a void under a structural concrete slab | |
| KR102068687B1 (en) | grating | |
| US4541218A (en) | Truss structures constructed with metal web members | |
| US2006929A (en) | Grating and grating bar and method of fabricating gratings | |
| DE6800650U (en) | TOOL FOR CHIPPING MACHINING OF A WORKPIECE AND DEVICE FOR ITS PRODUCTION. | |
| GB2121848A (en) | Wall studs and connectors therefor | |
| CH623395A5 (en) | Grating | |
| US1867702A (en) | Grating | |
| DE29921814U1 (en) | Floor panels | |
| DE10120788A1 (en) | Packaging element has two connecting pieces, extensible section with protuberance and sloping section. |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |