AU722506B2 - A peg assembly for supporting concrete formwork - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT 0* 0 Name of Applicant: Actual Inventor: Address for Service: Invention Title: SUPREMACY POOLS PTY LTD 063 240 700) Warren Leslie SNOW CULLEN

CO.,

Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

A PEG ASSEMBLY FOR SUPPORTING CONCRETE FORMWORK The following statement is a full description of this invention, including the best method of performing it known to us: A PEG ASSEMBLY FOR SUPPORTING CONCRETE FORMWORK This invention relates to a peg assembly which is used for supporting concrete formwork in a simple and safe manner. The invention will be described with reference to concrete formwork used in the manufacture of inground swimming pools but it should be appreciated that the invention need not be limited thereto and could also be used for other types of concrete formwork.

In the manufacture of inground swimming pools, a hole is dug to approximate the shape and size of the swimming pool. The hole is dug to have a substantially flat floor (this may be inclined to provide a shallow and deep end) and a vertical side wall. Reinforcement rods are placed in the hole and concrete is poured over the rods to provide the swimming pool shell. The upper part of the wall requires formwork to shape the edge of the concrete 1 pool. The formwork can be of various types but is usually in the form of a plywood panel having a height of approximately 10 to 30cm and which is supported around the periphery of the pool. The formwork panels need to be held in place by pegs in order to prevent deformation of the formwork panels during the concrete pour.

•A particular problem with formwork in swimming pools is that the 20 supporting pegs need to be hammered into the ground very close to the edge of the pool. Figure 1 illustrates a conventional prior art method of achieving this. In Figure 1, there is illustrated part of a pool excavation showing a bottom wall 10 and a vertical side wall 11. The top of the side wall becomes the coping 12, and a formwork panel 13 sits entirely around the vertical wall 11 but spaced away from wall 11 by a distance of typically 150mm. Panel 13 must be rigidly held in place and therefore must be pegged at regular intervals by wooden pegs 14. The wooden pegs 14 are braced with a bracing strut 15 which is nailed to a secondary peg 16. This arrangement must be repeated at approximately im intervals entirely around the pool and Figure 4 illustrates a rectangular pool where the right-hand side wall and the bottom wall are pegged according to prior art methods while the top wall and the lefthand side wall are pegged according to the peg assembly according to the invention.

A difficulty with existing bracing arrangements is that peg 14 must be nailed to panel 13 and therefore must be very close to side wall 11.

It is found that as wooden peg 14 is hammered into the ground, it often causes collapse of side wall 13 in the area shown as zone 17. Should this occur, the earth will crumble into the pool area and through the reinforcement mesh and this must be cleaned and rebraced prior to the concrete pour.

Another disadvantage with the existing arrangement illustrated in Figure 1 is that it takes a rather long time to hammer both pegs 14 and 16 and attach strut 15 to each of the two pegs every two metres or so around the perimeter of the pool. As the boxing, steeling and concrete pouring is usually *0* done in a single day, it is advantageous to find a method by which the pegs can be attached as quickly as possible.

Another disadvantage with the existing arrangement illustrated in Figure 1 is that rear peg 16 and brace 15 become a tripping hazard and a safety hazard. If peg 16 or brace 15 is tripped over, driven over or otherwise moved by workmen, hose pipe and the like, forward peg 14 will be jolted out of alignment and this can cause misalignment of panel 13 and/or crumbling of zone 17.

S 20o Pegs 14 are currently made of hardwood material in order to ensure that the pegs can be firmly hammered into even quite hard ground.

However, hardwood pegs are extremely difficult to nail and as each peg needs to be nailed to panel 13 and to bracing panel 15 and with the existence of rear peg 16, the entire arrangement is time consuming and quite clumsy.

Clearly, it is highly desirable that peg 14 is made from a softwood material such as pine as this can be much more easily nailed, however a peg made of pine will splinter when being hammered into the ground unless the ground is extremely soft (which is not common).

Another known bracing arrangement consists of a steel right angle bracket having a diagonal strut member. While these brackets find some use, the main disadvantage is that the two arm portions of the bracket are at exactly right angles and there is no adjustment possibility. This means that should the ground level be slightly inclined or even considerably inclined, the other arm member will extend at an angle other than 90 which will make it difficult to attach the formwork panel to the arm member at 90 Should this occur, it is necessary to chock or otherwise adjust the bracket such that the ground underneath the bracket is almost exactly horizontal and this is again a time consuming process.

The present invention is directed to a peg assembly which can replace the fairly clumsy arrangement illustrated in Figure 1 and which may overcome at least some of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

In one form, the invention resides in a peg assembly for supporting concrete formwork relative to the ground, the peg assembly having a rigid metal rod member which has a lower portion which can be hammered into the ground, and a channel member attached to the rod portion, the channel member having an open top end and being substantially U-shaped to define a back wall which is attached to the rod, a pair of spaced apart side walls which are parallel relative to each other, the outer edge of each side wall having a turned in lip, the lips facing each other and being spaced apart define a slot along the front of the channel member, the channel member being able to accept a wooden stake which can be slid into the channel member through the open top end, the turned in lips preventing the wooden stake from falling out through the slot, the slot allowing nails to be hammered into the wooden stake along its length.

In another form, the invention resides in the peg assembly as described above wherein the rod member has an upper end which extends above the channel member and which can be struck with a hammer to drive the rod member into the ground.

In a further form, the invention resides in a peg assembly for supporting concrete formwork relative to the ground, the peg assembly having a rigid rod member which can be hammered into the ground and having means to allow a wooden peg to be held relative to the rod member while still allowing the wooden peg to be nailed substantially along its length.

The peg assembly has a rigid metal rod member which can be formed from steel. The rod can be of various cross-section shapes but it is preferred that the rod is substantially circular. The steel rod can be formed from reinforcement bar. If desired, a lower part of the rod can be profiled to provide better grip in the ground. The lower end of the rod may be poipnted in order to facilitate it being hammered into the ground. The rod should be rigid in the sense that it does not readily bend when being hammered even into quite hard ground. It is found that a steel rod having a diameter of between 14 to 20mm is suitable. The length of the rod can vary but allowing for a good insertion of the rod into the ground, while still having an upper end of :the rod above the channel member, means that lengths of between 30 to 100cm are suitable. Of course, this length can vary. For instance, in very hard ground (where a hole might need to be drilled into the ground), the peg assembly can be quite short as the rod need not extend far into the ground.

The channel member may be made from good strong rigid material such as metal. A roll formed metal channel member is suitable with a wall thickness of between 2 to 5mm. The length of the channel member can vary to suit but for a typical use, a length of between 10 to 40cm may be suitable. The channel member has a back wall which is attached to the rod.

20 The attachment can be by various means such as welding, adhesive, use of fasteners, a combination of the above, and the like. It is possible for the channel member to be adjustably mounted to the rod such that the channel member can be length adjustable. For instance, the rod might be a threaded rod or a rod having threaded portions and the channel member may be provided with a nut and the like which can threadingly engage with the rod. A pin and slot arrangement or the use of separate fasteners is also envisaged to provide a degree of length adjustment to the channel member relative to the rod.

The channel member also has a pair of spaced apart side walls which are parallel to each other. The spacing between the side walls should be such to allow a wooden peg to slide along the channel member. It is envisaged that the wooden peg will have a width of between 20 to 50mm and a depth of between 10 to 30mm. Of course, this can again vary to suit but the channel member should be configured and sized to accept such a wooden peg.

The outer edge of each side wall has a turned in lip which are spaced apart to define a slot along the front of the channel member. An embodiment of this is illustrated in Figure 3. The size of the turned in lips should be sufficient such that a wooden stake passed into the channel member cannot be pulled out through the front of the channel member. It is however preferred that the lips are not so large that the resulting slot is l0 extremely narrow as it may be necessary to nail into the wooden stake along the slot and if the slot is too narrow, the nailing may become quite difficult.

In order to minimise damage to the channel member during S' insertion of the peg assembly into the ground, the rod may extend past the S-top of the channel member and this part of the rod can be struck by a hammer to drive the rod member into the ground.

S:An embodiment of the invention will be described with reference to the following drawings in which Figure 1 is a prior art example of supporting a formwork panel •13 in the manufacture of an inground swimming pool.

Figure 2 shows the same arrangement of Figure 1 but now with a peg assembly according to an embodiment of the invention.

Figure 3 is a front view of the peg assembly of Figure 2.

Figure 4 is a plan view of a rectangular swimming pool where the right-hand and bottom part of the swimming pool is braced using conventional prior art assemblies illustrated in Figure 1 while the top and the left-hand side of the pool is braced according to the peg assembly according to an embodiment of the invention.

Referring again initially to Figure 1, there is illustrated part of a swimming pool excavation which has a bottom wall 10, a side wall 11, and a coping area 12, one wall of which is defined by formwork panel 13. Panel 13 is formed from plywood and is nailed to a hardwood peg 14 which is hammered into the ground. Peg 14 is very close to side wall 11, and is usually approximately 150mm from the side wall, which means that area or zone 17 is susceptible to breaking and collapse during hammering in of peg 14. Peg 14 is braced by strut 15 which is nailed to peg 14 and the rear end of strut 15 is nailed to secondary peg 16 which is also hammered into the ground but now at a safe distance from side wall 11. This arrangement is quite time consuming and presents a safety hazard as brace 15 can easily be tripped over, stood on or knocked which in turn will effect peg 14.

Figures 2 and 3 show the peg assembly according to an embodiment of the invention. In this arrangement, peg assembly 20 is formed from a rigid round steel rod 21 having a diameter of 16mm, and which may be profiled as illustrated in Figure 3. Welded to rod 21 is a channel member 22. Channel member 22 is formed from roll formed metal and has a length of approximately 20mm and a wall thickness of about 2 to 3mm.

Channel member 22 has a back wall 23 which is welded to rod 21. A pair of side walls 24, 25 are provided which are spaced apart and parallel to each other. The free end of each side wall has a turned in lip 26, 27 where the lips S"face each other. Between the lips is defined a slot 28. In use, the rod containing the attached channel member is hammered into the ground close S•to side wall 11, but as the rod is a very small diameter with respect to the hardwood stake 14, very little damage (if any) occurs in zone 17. Typically, the rod is hammered into the ground until the bottom of channel member 22 sits on the ground surface. A softwood (typically pine) stake 30 (see Figure 2) can be slid down channel member 22 until the bottom of the stake sits on the ground. While stake 30 can be lifted out of the channel, it cannot be pulled forwardly through slot 28 due to the turned in lips 26, 27. The formwork panel 13 can be nailed to the softwood stake 30 through slot 28 which means that substantially the entire length of stake 30 is available for nailing.

The procedure can be duplicated at regular intervals (typically 1 to 2m) around the periphery of the pool and it is a fairly simple procedure to simply hammer the peg assemblies into the ground and then simply slide a softwood stake into the channel member and then nail the formwork panel into the softwood stake.

8 The arrangement does away with the requirement for the secondary peg 16 and the bracing member 15 as the steel peg is sufficient rigid to prevent being bent. For the first time, a softwood stake 30 can be used doing away with the hardwood pegs 14 which means that nailing is extremely simple. There is very little likelihood of damage in the zone 17 as the steel bar is of much narrower diameter and generally requires less hammering to hammer it into the ground. As there is no brace 15 and secondary peg 17, a tripping hazard is virtually eliminated. The softwood peg does not require a point, thereby doing away with the need to sharpen the ends of each peg. The channel can be provided with a, or aplurality of, small protrubance(s) to hold the stake 30 more tightly in the channel. These can be formed by making small saw cuts in the channel and deforming the wall between the cuts into the channel.

•Another advantage with the peg assembly is that it can be reused an almost unlimited number of times which is contrary to the hardwood stakes which will wear and splinter over time.

It should be appreciated that various other changes and modifications may be made to the invention described without departing from the spirit and scope of the invention as claimed.

Claims (9)

1. A peg assembly for supporting concrete formwork relative to the ground, the peg assembly having a rigid metal rod member which has a lower portion which can be hammered into the ground, and a channel member attached to the rod portion, the channel member having an open top end and being substantially U-shaped to define a back wall which is attached to the rod, a pair of spaced apart side walls which are parallel relative to each other, the outer edge of each side wall having a turned in lip, the lips facing each other and being spaced apart to define a slot along the front of the channel l0 member, the channel member being able to accept a wooden stake which can be slid into the channel member through the open top end, the turned in lips preventing the wooden stake from falling out through the slot, the slot allowing nails to be hammered into the wooden stake along its length.

2. The assembly of claim 1, wherein the rod member has an upper end which extends above the channel member and which can be struck with a hammer to drive the rod member into the ground.

The assembly of claim 1 or claim 2, wherein the rod member is cylindrical and has a diameter of between 14mm to

4. The assembly of any one of the preceding claims, wherein the rod member has a length of between 30cm to 100cm.

5. The assembly as claimed in any one of the preceding claims, wherein the channel member has a wall thickness of between 2mm to

6. The assembly as claimed in any one of the preceding claims, wherein the channel member has a length of between 10cm to

7. The assembly of any one of the preceding claims, wherein the channel member is adjustably mounted to the rod member such that the channel member can be length adjustable along the rod member.

8. The assembly of any one of the preceding claims, wherein the side walls of the channel member are spaced apart between 20mm to

9. The assembly of any one of the preceding claims, wherein the spacing between the turned in lip and the back wall of the channel member is between 10mm to A peg assembly substantially as hereinbefore described with reference to Figures 2, 3 and 4. DATED this 11 th day of November 1999 SUPREMACY POOLS PTY LTD 063 240 700) By their Patent Attorneys CULLEN CO. e **aa