GB2208623A - Concrete posts - Google Patents

Abstract

There is disclosed an open-topped mould for the production of a wet-cast slotted concrete post (10) comprising a sloping base (31) and ribbed side walls (32,33) movable from positions perpendicular to the base to outwardly angled positions disengaged from the sides of a post cast in the mould, to permit pushing of the post from the mould. <IMAGE>

Description

CONCRETE POSTS This invention concerns wet-cast slotted concrete posts and methods and apparatus for making them.

Slotted concrete posts, as used in fencing structures, may be cast from either relatively dry or relatively wet concrete mixes. The wet-cast posts have an excellent surface finish compared with dry-cast posts but have the disadvantage of a lengthy manufacturing process requiring to remain for up to twenty four hours in the mould after pouring.

Traditionally wet-cast slotted posts have been hand made using moulds having hinged sides to facilitate removal and it has in fact been the difficulty of removal from the mould without spoiling the outer surfaces which has frustrated attempts hitherto in automating production.

The present invention is based upon the discovery that if one face of a slotted concrete post tapers from the root of the post to the top of the post and that if such post is cast in a mould whose sides can be disengaged from intimate contact with the sides of the post it can be pushed axially from the mould without damage to its surfaces thus providing the possibility of automatic production.

According to one aspect of the invention, then, there is provided an open topped mould for the production of a wet-cast slotted concreting post, the mould having a sloping base and ribbed sides which can be moved from planes perpendicular with the plane of said base away from one another to be disengaged from intimate contact with the sides of a post cast in the mould to permit pushing of the post from the mould.

The sides of the mould may be of a springy material enabling flexing between the perpendicular and disengaged positions.

A plurality of said moulds may be provided in side-by-side relationship to form an assembly compressible in a transverse direction to cause the sides of the moulds to assume their vertical positions for pouring and extendible to allow said sides to assume their disengaged positions for ejection of the posts.

A multiplicity of such assemblies may be provided in a rack arrangement wherein each is moved step-by-step around a closed loop path commencing at a pouring station and terminating at an ejection station.

According to another aspect of the invention is a wet-cast slotted concrete post produced in any mould as aforesaid.

The invention will be further apparent from the following description, with reference to the figures of the accompanying drawings, which show, by way of example only, one form of post and moulds for making same, all embodying the invention.

Of the drawings: Figure 1 shows a front view of the concrete post; Figure 2 shows a side view of the post of Figure 1, Figure 3 shows a transverse cross-section through a mould for the production of the post of Figures 1 and 2; Figure 4 shows a cross-section through the mould on the line IV-IV of Figure 3; Figure 5 shows a transverse cross-section through a plurality of moulds in side-by-side relationship and forming an assembly thereof; and Figure 6 shows how a multiplicity of the assemblies of Figure 5 may be included in a rack arrangement for continuous production of the posts.

Referring firstly to Figures 1 and 2, it will be seen that a wet-cast slotted concrete post 10 embodying the invention is of an overall rectangular cross-section which reduces in area from the root 11 to the top 12 of the post, the rear face of the post tapering inwardly from the root to the top by some 3 cm over the 250 cm height of the post. The sides 14 and 15 of the post are provided with vertically extending slots 16 adapted to receive sections of panel fencing and the upper end of the post terminates in a pyramidal cap 17.

The post is manufactured by casting in an open-topped mould.

As can be seen from Figures 3 and 4, the opentopped mould 30 has a sloping base 31 and side walls 32 and 33 profiled to form the slots 16. The side walls 32 and 33 are formed from a springy sheet steel or laminated plastics material to enable them to flex from planes perpendicular with the plane of the base 31 outwardly to the positions indicated in chain-dotted lines wherein they are disengaged from intimate contact with the sides of a post which has been cast in the mould 30.

A post which has been cast in the mould can be slid therefrom by pushing in an axial direction.

As shown in Figure 5 a plurality of the moulds 30 can be arranged in side-by-side relationship to form an assembly 50. Adjacent moulds 30 are separated by a vertical wall 51 and further walls 52 are provided at the opposite sides of the assembly. The upper edges of the walls 32 and 33 are joined with the upper edges of the walls 51 and 52. The walls 51 and 52 are movable laterally over a base member 53. An actuating ram arrangement 54 may be operated to move the walls 52 towards one another to compress the assembly to cause the side walls 32 and 33 of the moulds 30 to take up their perpendicular positions lying against the faces of the walls 51 and 52 and away from one another to extend the assembly and cause the walls 32 and 33 to flex outwardly to become disengaged from intimate contact with the sides of posts which have been cast in the moulds.

As shown in Figure 6 a multiplicity of the assemblies 50 can be arranged in a rack arrangement.

The assemblies 50 may be indexed around a closed loop path commencing at a pouring station 60 and terminating at an ejection station 61.

Means 62 for pouring concrete into the moulds 30 is provided at station 60 and a pusher arrangement 63 for ejecting posts from the moulds 30 is provided at station 61.

It will be understood that the time taken for an assembly to move around the path from station 60 to station 61 will be at least sufficient to allow the concrete to cure to a stage permitting ejection and subsequent mechanical handling of the posts.

Ram arrangements 54 are provided at the stations 60 and 61 for compressing and extending the assemblies 50 which travel in the rack in their compressed condition.

It will be appreciated that it is not intended to limit the invention to the above example only, many variations, such as might readily occur to one skilled in the art, being possible, without departing from the scope thereof.

Claims (9)

1. An open topped mould for the production of a wet-cast slotted concreting post, the mould having a sloping base and ribbed sides which can be moved from planes perpendicular with the plane of said base away from one another to be disengaged from intimate contact with the sides of a post cast in the mould to permit pushing of the post from the mould.

2. A mould according to claim 1 wherein the sides of the mould are of a springy material enabling flexing between the perpendicular and disengaged positions.

3. A mould according to claim 2 wherein the sides of the mould are of a laminated plastics material.

4. A plurality of moulds according to any preceding claim arranged in side-by-side relationship to form an assembly compressible in a transverse direction to cause the sides of the moulds to assume vertical positions for pouring and extendible to allow said sides to assume their disengaged positions for ejection of the posts.

5. A multiplicity of assemblies according to claim 4 provided in a rack arrangement wherein each is moved step-by-step around a closed loop path commencing at a pouring station and terminating at an ejection station.

6. An arrangement according to claim 5 wherein there is a ram arrangement at each of the pouring and ejecting stations for extending and compressing the mould asssemblies respectively.

7. An arrangement according to claim 6 wherein there is a pusher arrangement at the ejection station for ejecting the posts axially from the moulds.

8. A wet-cast slotted concrete post produced in a mould as claimed in claim 1.

9. A method of producing a wet-cast slotted concrete post comprising casting same in a mould as claimed in claim 1.