STANCHION OR POST

Abstract: A stanchion or post suitable for use as a supporting post attachable to a scaffolding plate or board (9) on which a workperson can stand, said stancheon or post comprising inner and outer tubes (1, 1 a ),(2, 2 a ) and a clamping means (A, B) so that it can be clamped to the scaffolding plate or board (9) or any other support, which clamping is performed by sliding the inner and outer tubes (1, 1 a ), (2, 2 a ) relative to each other and/or by adjusting the clamping means (A, B) together with the inner and outer tubes (1, 1 a ), (2, 2 a ), or independently.

Description: The present invention relates to a stanchion or post, and more particularly, but not exclusively, to a stanchion or a supporting post suitable for supporting a handrail of scaffolding for supporting workers and working machines in building construction sites, ship building and repair, civil engineering work, etc. In general, in building construction, ship building, assembly and repair or civil engineering work, most of the work is performed at heights considerably higher than ground level by using scaffolding. Handrails are provided on such scaffolding by means of stanchions having tubes or ropes secured thereto, which scaffolding is assembled by arranging walkway plates or boards to the side of the object being constructed or repaired in order to enable the safe movement of workers or operating machinery. As for road works, wires or ropes are stretched horizontally in order to limit the construction site. In order to stretch ropes and wires, and support horizontal tubes and other means to scaffoldings or to limit a construction site, it is necessary to provide a stanchion for supporting such ropes, wires, tubes and other means. To provide scaffolding and construction sites with such stanchions, welding to other steel materials, clamping by using bolts and nuts, binding by ropes or any other methods are applied, which not ony require very troublesome work upon their installation and removal, thus lowering the working efficiency, but also they are very uneconomical because of the requirement of many workers, tools and components. Moreover, depending upon the condition of the construction site many posts or stanchions of different lengths are often required which results in considerable expense by requiring large numbers of components differing in length. Further, when the thickness of the plates or boards used for scaffolding vary, it is inevitable to have to use the stanchions corresponding to the thickness of the plates or boards used. In addition, the fixing of ropes or wires to stanchions by knotting also results in bad economy of operation together with very low operative efficiency. Patent specification US-A-3938619 describes a stanchion for clamping to a support structure of the type comprising: an elongate member; a tubular member slidably mounted on the elongate member; means for releasably fixing the tubular member to the elongate member in any selected one of a plurality of positions; a pair of parallel opposed clamping jaws mounted on the elongate member and tubular member, respectively, one of the jaws comprising a screw-threaded socket into which an adjustable screw-threaded jaw-piece is fitted, such that, with the fixing means holding the tubular member at a desired position on the elongate member, the jaws can be clamped onto the support structure with one of the members extending upwardly from the structure; and a fitting mounted on the upwardly extending member for supporting a rope or handrail. Specifically, the stanchion of US-A-3938619 has support members of circular cross-section, and the fixing means comprises a pin which is passed through selectably aligned holes in the support member. A disadvantage with this known stanchion is that, during adjustment of the overall length of the stanchion, the support members may come completely apart. Also, when lining up the holes for the pin of the fixing means, it is necessary to adjust one support member with respect to the other rotationally in addition to longitudinally. According to the invention, there is provided a stanchion for clamping to a support plate or board, comprising: an elongate member; a tubular member slidably mounted on the elongate member; means for releasably fixing the tubular member to the elongate member in any selected one of a plurality of positions; clamping means including a pair of parallel opposed clamping jaws mounted on the elongate member and tubular member, respectively, a first one of the jaws comprising a screw-threaded socket into which an adjustable screw-threaded bolt having a first jaw-piece is fitted, and the other jaw being disposed parallel with and spaced from the first jaw, such that, with the fixing means holding the tubular member at the desired position on the elongate member, the jaws can be clamped onto the support structure with one of the members extending upwardly from the structure, the bolt being rotatable to move the first jaw towards and away from the other jaw; and a fitting mounted on the tubular member for supporting a rope or handrail at a position located above the clamping means, characterised in that: the elongate member has a rectangular cross-section; the tubular member has a complementary rectangular portion so that the tubular member and the elongate member are prevented from rotating relative to each other; and means are provided to prevent the elongate member and tubular member becoming disengaged when the releasable fixing means is released. Some embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevational view of a stanchion according to the prior art showing the stanchion mounted on a scaffolding plate or board; Figure 2 is an enlarged cross-sectional view of a clamping means of the stanchion of Figure 1; Figure 3 is a side elevational view of a modified stanchion according to the present invention; Figure 4 is a cross-sectional view taken along line A-A of Figure 3; and Figure 5 is a perspective view of an upper portion of an inner tube of Figure 3. Figures 6 and 7 are half cross-sectional views respectively showing elastic materials used in the stanchion of Figure 3. Figures 1 and 2 show a known device, in which the stanchion or post comprises a tubular body 2 which is vertically slidably inserted in an outer tubular body 1. The outer body 1 is provided with a plurality of holes 3 located at equally spaced vertical locations along its height. The inner tubular body 2 is also provided with holes 4 in correspondence with the holes 3 provided in the outer tubular body 1 and at equal spacing. A laterally extending bracket 5 is fixed to the lower end of the inner tubular body 2, and a dish 7 is provided on a bracket 5. The dish 7 contains an elastomeric material 6, such as hard rubber, and the dish 7 and the elastomeric material 6 form the lower part A of a clamping means. The clamping means includes a freely expansible upper part B which is fixed to the outer tube 1 by a bracket 8 and which extends downwardly. The clamping means constituted by the lower part A and upper part B serves to clamp against the scaffolding plate or board 9 from both sides of the plate or board. The upper part B of the clamping means comprises a cylindrical body 10 and a nut 11 fixed within the cylindrical body 10. A bolt 12 is engaged with the cylindrical body 10 through the nut 11 and may be threadably adjusted therein vertically. To the lower end of the bolt 12 is fixed a dish 15 which is fixed by the head portion 13 of the bolt 12 and a nut 14. An elastomeric material 16, such as hard rubber, is contained in the dish 15. A pin 18 is connected to the bracket 8 through a chain 17 and can be inserted through aligned holes 3 and 4. The stanchion is secured to the scaffolding plate or hoard 9 by the following steps: If the thickness of a scaffolding plate or board 9 is considerably large, the inner tube 2 is slidably extended in correspondence with the thickness of the scaffolding plate or board 9 and at the location to align the hole 3 of the outer tube 1 with a hole 4 of the inner tube 2, and the pin 18 is inserted through the aligned holes 3 and 4 to fix the inner tube 2. With this arrangement, it is possible to adjust the length of the stanchion composed of the outer tube 1 and the inner tube 2. Subsequently, the elastomeric material 6 of the lower clamping means A is applied to the lower surface of the scaffolding plate or board 9, and the upper clamping means B is located above the upper surface of the scaffolding plate or board 9. Thereafter, the elastic material 16 is applied to the plate or board 9 by rotating the head 13 of the bolt 12 and lower it. As a result, the scaffolding plate or board 9 is tightly clamped by means of the upper and lower parts A and B of the clamping means to fix the outer and inner tubes 1 and 2 tightly to the scaffolding plate or board 9. If the thickness of a scaffolding plate or board 9 is considerably small, it is possible to mount the stanchion to the scaffolding plate or board 9 simply only by sliding the inner tube 2 upwardly and by adjusting the upper part B of the clamping means. After completion of the mounting of the stanchion to the scaffolding plate or board 9, it is possible to form a handrail by attaching ropes 21 and 22 to fittings 19 and 20 provided on the upper portion of the outer tube 1. Figures 3 to 7 show a stanchion according to an embodiment of the invention which is similar in construction to some extent, to the stanchion of Figure 1. Therefore, like reference numerals designate similar parts, and their detail description is omitted. In the embodiment of Figure 3 an inner tubular body 2 a is slidably inserted through an outer tubular body 1 a . The outer tubular body 1 a is in the shape of a cylinder with its lower end 1 b of a small diameter, while the inside tubular body 2 a is in the shape of a hollow rectangular shape, as shown in Figure 4. As shown in Figure 5, the inside tubular body 2 a has in its upper end a pair of diametrically opposed cut-outs a , forming a pair of tongues 2 b , each extending obliquely outwardly from a peripheral edge of the respective cut-out a and serving as a stop. The inside tubular body 2 a may be formed by shaping a cylindrical tube into a rectangular hexahedron, or a tube in the shape of a rectangular hexahedron may be used for the inside tubular body 2 a . The rectangular hexahedron causes an increased degree of strength and serves to prevent the inside tubular body 2 a from being displaced in circumferential directions. The inside tubular body 2 a is inserted into the outer tubular body 1 a from the upper end thereof and; as the upper end of the inside tubular body 2 a arrives at the lower end of the outer tubular body 1 a , the two tongues 2 b are brought into engagement with the small-diameter portion, thus preventing the inside tubular body 2 a from being removed from the outer tubular body 1 a . With this arrangement, it is unnecessary to provide a special stop, and the inside and outer tubular bodies 2 a , 1 a can be assembled together with ease. One or more mounting members 32 are mounted on a peripheral surface of the outer tubular body 1 a , through which members a handrail such as a rope or tube may be threaded. A hook bolt d is inserted horizontally through the upper portion of the outer tubular body 1 a and is secured at one end by a nut e . The hook bolt d is adapted to receive or support a handrail in the form of a tube. A dish 7 a mounted on the bracket 5 has a central hole, through which a downwardly tapered locking portion 6 b of the elastomeric material 6 a is to be forcibly inserted at that time the diameter of the locking portion 6 b becomes smaller and, upon insertion, then recovers under its own elasticity, thus preventing the elastomeric material 6 a from being removed from the dish 7 a . A dish 15 disposed at the upper part B has an inside taper surface, in which an upwardly outwardly diverging taper surface f (Figure of the elastomeric material 16 a is to be fitted so as to prevent the elastomeric material 16 a from being removed from the dish 15. The outer tubular body 1 a has in its lower portion a pair of holes 3a, while the inside tubular body 2 a has a plurality of holes 4 a spaced at equal distance twice the distance between the two holes 3 a in the outer tubular body 1 a . With these holes 4 a , the inside tubular body 2 a can be varied in the range of vertical adjustment. For instance, if the distance between the adjacent holes 3 a is 60 mm and the distance between the holes 4 a is 120 mm, the inside tubular body 2 a can be longitudinally adjusted within a range from 60 mm to 180 mm. With the stanchion according to the present invention, the following advantageous results can be achieved: (1) The stanchion can be attached to a plate or board as a scaffolding plate or board, irrespective of the thickness of the plate or board. (2) Since the inside tubular body is rectangular it will not move circumferentially relative to the outer tubular body and since it is tightened by means of a bolt and nut, a very simple mounting can be achieved. (3) Since the inside tubular body can be accommodated within the outer tubular body, the stanchion can be longitudinally reduced into a compact size convenient to carry about and easy to keep in storage.

Claims: A stanchion for clamping to a support plate or board, comprising: an elongate member (2a); a tubular member (1a) slidably mounted on the elongate member (2a); means (3a, 4a) for releasably fixing the tubular member (1a) to the elongate member in any selected one of a plurality of positions; clamping means including a pair of parallel opposed clamping jaws (A, B) mounted on the elongate member and tubular member, respectively, a first one of the jaws (B) comprising a screw-threaded socket (11) into which an adjustable screw-threaded bolt having a first jaw-piece (15) is fitted, and the other jaw (A) being disposed parallel with and spaced from the first jaw (B), such that, with the fixing means holding the tubular member at the desired position on the elongate member, the jaws can be clamped onto the support structure with one of the members extending upwardly from the structure, the bolt being rotatable to move the first jaw (B) towards and away from the other jaw (A); and a fitting mounted on the tubular member for supporting a rope or handrail at a position located above the clamping means, characterised in that: the elongate member has a rectangular cross-section; the tubular member has a complementary rectangular portion (1a) so that the tubular member and the elongate member are prevented from rotating relative to each other; and means are provided to prevent the elongate member and tubular member becoming disengaged when the releasable fixing means is released. A stanchion as claimed in claim 1, wherein the disengagement preventing means comprises an outwardly diverging stop at an end of the elongate member within the tubular member. A stanchion as claimed in claim 1 or 2, wherein the clamping jaws have respective snap -fitted clamping pads.

Inventors: ENOKI, TAKAHIRO, MASUDA, AKIRA
Applicants: NISSO SANGYO CO LTD
Application year: 1988
Main classification: E04G21
IPC codes: E04G21