GB2233276A

GB2233276A - Apparatus and process for forming building blocks

Info

Publication number: GB2233276A
Application number: GB9014372A
Authority: GB
Inventors: Bernard Parfrement
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-06-28
Filing date: 1990-06-28
Publication date: 1991-01-09
Also published as: GB9014372D0; GB8914818D0

Abstract

A die box (2) comprises a pair of removable side die plates (6), a base plate (23), from which projects a spigot (40) for forming a longer slot (140) and a spigot (50) for forming a shorter slot (150) opening from the opposite sides of card extending from one end of the block, and an openable lid (74) opposite the base plate (23), incorporating another spigot (51) for forming another similar shorter slot (151) in the other end of the block. Rams (20) apply pressure to die plates (6) optionally via a pair of spacer plates (21) to effect compression of cementitous material from which the block is to be formed. The block is ejected from the die box by an ejection ram (100) extending slidably through an opening in the base plate (23). The die box is provided with a semi-dry mix, the block is formed and then removed from the die box while holding its shape and allowing it to cure elsewhere. <IMAGE>

Description

APPARATUS AND PROCESS FOR FORMING BUILDING BLOCKS This invention relates to an apparatus and process for forming building blocks for the construction of dry walls and also to the building blocks made therewith.

In UK granted patent GB 1,332,297, the disclosure of which is incorporated herein by reference, there is described a building block for the construction of dry walls, which comprises a substantially rectangular body, one surface of which is provided with a longitudinal slot of enlarged inner cross-section, and the opposite surface of which is provided at each end with a shorter slot also of enlarged inner cross-section, one of the surfaces having a raised longitudinally extending central region and the opposite surface having a recessed longitudinally extending central region, such that two similar blocks can be stacked with the raised region of one located in the recessed region of the other, and when so stacked the mouths of the slots in adjacent surfaces of the two blocks will be in alignment.

In one aspect of the present invention a building block is provided having a similar shape and form to the block disclosed in GB 1,332,297, but which incorporates a number of modifications.

In second and third aspects of the present invention there are provided respectively an apparatus and a process suitable for forming the building blocks of the first aspect of the invention.

Within the scope of this invention is a dry wall built using the blocks so produced, in which the blocks are held together using a joggle system similar to that described in GB 1,332,297.

The apparatus of the invention, which may be bench or floor mounted, comprises in combination the following components: a die box within which the block is to be formed, comprising a pair of opposite end walls, a pair of opposite side walls, preferably provided by removable die plates, and a base from which projects at least one spigot for preforming a said slot in one end of the block, a removable lid for the die box, incorporating at least one further spigot for preforming a said slot in the opposite end of the block, opposing pressure means, e.g. compression rams, for applying pressure to said opposite side walls to effect compression of material from which the block is to be formed.

Preferably there is provided ejection means, such as an ejection ram, operating in a direction parallel to said spigots, for ejecting the block from the die box after it has been formed.

Preferably the spigot which forms the longitudinal slot and a spigot for forming one of the shorter slots project upwardly from the base of the die box, and a spigot for forming the other shorter slot is provided on the lid to the die box. The latter spigot is preferably provided by a spigot element retractably mounted on the lid so as to be advanced into an operative position projecting into the die box, and retracted therefrom, while the lid is in position closing the die box.

Suitably, a clamp mechanism is provided for movement into and out of an operative position in which it clamps the lid in the closed condition, the movement of the clamp mechanism into and away from said operative position effecting the advance and retraction of said spigot element on the lid.

Normally the material used for forming the blocks will be a semi-dry mix, as is known in the art, comprising a cementitious composition and an amount of moisture which is sufficient to activate the cement and to make the mixture cohesive, while allowing a block once formed in the die box, to be removed while holding its shape and allowed to cure elsewhere. Thus, no curing step of the mix within the die box is necessary, which allows the moulding process to be carried out efficiently and with little break in between individual moulding operations.

By way of example only, preferred embodiments of the various aspects of the invention will now be described in detail, with reference to the accompanying drawings, wherein Figure 1 is a plan view of part of an apparatus for making the blocks; Figure 2 is a cross-sectional side view of part of the apparatus of Figure 1; Figures 3(a) and (b) are diagrammatical side views of the lid arrangement of the apparatus of Figure 2, in the part-open and closed conditions, respectively; Figure 4 is a plan view of a base pallet for use in the apparatus; Figure 5 is a perspective view of a preferred building block hereof; and Figures 6(a)-(d) show variations in the relative profiles of the slots of the building blocks and the joggles used in joining them together to form a dry wall.

Referring firstly to Figures 1 and 2, the apparatus 1 comprises a rectangular frame having opposite pairs of plates 12 and 14 respectively, and held together by straps 10 and bolts 13. In these Figures, only the central portion and the left-hand end of the apparatus are shown for ease of reference; (the right-hand end of the apparatus comprises the same components as the lefthand end and any reference to such features should be understood as applying to both the left-hand end and the right-hand end alike).A die box 2 is defined by a number of operative elements, namely a pair of die plates 6; a base plate 23; an openable lid 74 opposite the base plate 23; a wall plate 16 to which is attached a pad 18 which is shaped so as to form the desired bottom surface of the block; pads 24 secured to the die plates 6 which are shaped so as to form (together with the adjacent plate 14) the desired top surface of the block; and spigots 40, 50, 51, a longer spigot 40 and shorter spigot 50 being fast with, and upstanding from, the base plate 23, and another shorter spigot 51 being mounted in the lid 74.

Rams 20, which may be hydraulically or pneumatically driven, provide compressive force for moulding the material in the die box. The rams may be double-acting, but as shown they are single acting, their return action being provided by springs 36.acting on piston rods 35.

Each ram terminates in a piston plate 8 sliding between the side plates 14, and each piston plate bears upon a respective spacer plate 21 which in turn bears upon respective die plates 6. Stops 30 extend into the die box from one of the side plates 14, and, together with the wall plate 16, limit inward movement of the spacer plates 21, and thus also the die plates 6, when acted upon by the rams.

The material to form the block is compressed from both sides, that is both rams apply a compressive force, so that the semi-dry mix material is formed evenly around the whole of the exposed surface of the spigots. When pressure from the rams is released, the springs 36 retract the piston plates 8, thereby releasing the pressure on spacer plates 21 and the die plates 6, thus allowing the newly formed block to be removed. In the preferred embodiment hereof the block is removed from the die box by means of an ejection ram 100 which extends slidably through an opening in the base plate 23.

Figures 3(a) and 3(b) show in more detail the lid arrangement of the die box, in the part-open and closed conditions, respectively. The lid 74 is attached to the upper part of the die box by a hinge 66, while a clamping member 80 is attached to the die box by an adjacent hinge 67. On the top of the lid 74 is mounted a bracket 79 which slidably carries a bolt 72 loaded by a spring 76, the lower end of the bolt terminating in spigot 51 for forming the short slot at the adjacent end of the block.

The spigot 51 extends slidably through an aperture 77 in the lid, the spring 76 urging the spigot upwards so as to lie within the aperture 77 flush with the underside of the plate 74. Upward travel of the spigot is limited by means of a pin 83 which engages with the underside of the bracket 79 when the spigot is in its maximum upward position.

The clamping member 80 carries an adjustment screw 84, which may be raised or lowered as desired. As the clamping member 80 is brought down onto the lid as shown in Figure 3(b), the final part of the motion causes the adjustment screw 84 to engage the bolt 72 and depresses it against the force of the spring 76, thereby advancing the spigot 51 below the lid and into the die box. Upon closure of the lid, the distance by which the spigot 51 is forced to protrude into the die box thus determines the longitudinal extent of the slot which is formed in the end of the block, and can be varied as required by adjustment of screw 84. The clamping member is fastened shut by any suitable means, e.g. a toggle action latch 90, or by hydraulic or pneumatic pressure.

It will be apparent that on raising the clamping member 80 after the moulding cycle, the spigot 51 is retracted from the die box cleanly and at right-angles to the lid 74 prior to raising the lid. This avoids any deformation of the sides of the newly formed slot, which would otherwise occur, owing to the rotational motion of the lid about its hinge.

Prior to each moulding cycle a base pallet 110, consisting of a thin sheet of metal or other suitable material, is inserted into the die box to act as a support for the newly formed block as it is ejected.

Such a pallet will normally take the form shown in Figure 4, the cut-out portions 116 and 118 allowing the pallet to be ejected from the die box by sliding over the spigots 40, 50.

Figure 5 shows a preferred form of building block in accordance with the invention. The block is similar in form and shape to that described in GB 1,332,297, but now the longitudinal slot 140 in the upper surface of the block extends from one end only'part-way, preferably just over half-way, along the block. This modification over the prior art has been found to give the block added strength, which is particularly important in the building of dry walls, where blocks are stacked one upon another.

The shorter upper longitudinal slot also results in easier removal of the blocks from the die box. It also facilitates more accurate locating of successive courses of blocks, since the joggle to be located in a pair of short slots 150/151 of-longitudinally adjacent blocks can be located at the end of the longer slot 140 in the block below, thereby ensuring that adjacent courses are longitudinally displaced by a half-block length in conventional manner.

For building a dry wall using the blocks of the invention, the same geometric form of jointing is used as described in GB 1,332,297, using joggles. Preferably, the joggles will be made of a resilient extruded plastic, e.g. polypropylene. To build a dry wall using the blocks of this invention, a similar procedure as described in GB 1332297 will be used. Obviously, however, since the upper longitudinal slot 140 only extends approximately half-way across the upper surface of the block, the respective joggle can only be inserted into this slot from one end of the block.

In this description the slots of the block are shown as being formed with a rounded profile, which will match with similarly shaped joggles. However, other shaped slots may be utilised, by substituting appropriately profiled spigots, which may or may not have the same profile as the joggles to be used for holding together the blocks.

Figure 6 shows variations in the slot and joggle profiles, any of which, and others not shown, may be used within the scope of the present invention. The system shown in Figure 6(a) is, however, preferred. In Fig. 6 the combined slot is indicated at 200, the joint between adjacent blocks at 205, and the joggle at 210. The space between the joggles and the walls of the slots has been somewhat exaggerated for clarity.

By way of example, the process of the invention may be carried out in the following manner.

(i). Insert the die plates and base pallet into the die box.

(ii). Charge the die box with a pre-determined amount of material to be moulded into a block, which amount is based on, for example, the volume of the die box and the desired density of the resulting block. The material may be poured or injected by hand, hopper fed or introduced by other suitable means.

(iii). Close and fasten the lid of the die box, which may be accomplished by hand or by powered means.

In doing so the end spigot 51 is pressed into the material.

(iv). Activate the compression rams 20, which compress the material to a prescribed density and shape and form the material around the spigots. The pressure used is regulated by the stops, and adjustment screws (not shown) may be included to take account of variations due to wear of the operative elements.

(v). On completion of the moulding cycle, the compression rams and the upper spigot 51 are retracted, and the lid of the die box opened.

(vi). The finished block, supported on the base pallet, is ejected from the die box, either manually or preferably by means of the ejection ram 100. Preferably the finished block is removed still within its protective die plates, which may be subsequently removed and replaced in the die box.

(vii). The finished block is left to harden and dry.

In this description the apparatus has been described in the vertical mode, i.e. the material is fed into the die box and the moulded block removed from above.

However, the same principles are applicable in the horizontal mode for ease of ejection in volume production.

It will be apparent that many other detailed aspects of the apparatus design may be altered within the scope of this invention, for example to provide powered and/or automated action of the various components.

Various forms of die plates may be used, depending on the required finish, size and aesthetic appeal of the finished blocks. Different thicknesses of spacer plates can be used to vary the compression on the block during the moulding step.

Claims

1. An apparatus for forming building blocks comprising: a die box within which the block is to be formed, comprising first and second pairs of opposite end walls defining a generally cuboidal space; a base from which at least one spigot projects adjacent an end wall of said first pair for preforming a slot opening in one end of the block, an openable lid for the die box, incorporating at least one further spigot which in the closed configuration of the lid projects adjacent an end wall of said first pair for preforming a slot opening in the opposite end of the block, and opposing pressure means, for applying pressure to the walls of one of said pairs of opposite side walls to effect compression of material from which the block is to be formed.

2. An apparatus according to claim 1 wherein said opposing pressure means apply pressure to said second pair of end walls.

3. An apparatus according to claim 1 or 2 having ejection means operating in a direction parallel to said spigots, for ejecting the block from the die box after it has been formed.

4. An apparatus according to any preceding claim wherein said second pair of opposite end walls are provided by removable die plates.

5. An apparatus according to claim 4 as appendant on claim 2 including spacer plates which are interposable between the pressure means and the die plates.

6. An apparatus according to claim 5 having a pair of elongate side walls portions of which define at least part of said first pair of end walls; said die plates being mountable between said sidewalls at variable mutual spacings whereby blocks differing in one dimension can be produced.

7. An apparatus according to any one of the preceding claims wherein said opposing pressure means are compression rams.

8. An apparatus according to any one of the preceding claims having two said spigots projecting from said base of the die box adjacent different ones of said first pair of ends walls one being relatively long and the other being relatively short, for forming long and short slots: and the spigot provided on the lid of the die box being relatively short for forming another short slot.

9. An apparatus according to claim 8 wherein said spigot provided on the lid of the die box is a spigot element retractably mounted on the lid so as to be advanced into an operative position projecting into the die box, and retracted therefrom, while the lid is in position closing the die box.

10. An apparatus according to claim 9 having a clamping means for clamping the lid in the closed position; the movement of the clamping means into and away from its clamping configuration effecting the advance and retraction of said spigot element on the lid.

11. An apparatus for forming building blocks substantially as described herein with reference to the accompanying drawings.

12. A process for forming building blocks using the apparatus according to any one of the preceding claims comprising forming a block in the die box with a semi-dry mix comprising a cementitious composition and an amount of moisture which is sufficient to activate the cement and to make the mixture cohesive, removing it and allowing it to cure elsewhere.

13. A process according to claim 12 wherein prior to each molding cycle a base pallet is inserted into the die box to act as a support to the newly formed block.

14. A process according to claim 13 wherein said base pallet is a thin sheet of metal.

15. A process according to claim 13 or 14 comprising: (i) Inserting the die plates and base pallet into the die box, (ii) Charging the die box with a pre-determined amount of material to be moulded into a block, which amount is based on the volume of the die box and the desired density of the resulting block, (iii) Closing and fastening the lid of the die box, thereby pressing the spigot mounted on the lid into the material, (iv) Activating the opposing pressure means which compress the material to a prescribed density and shape and form the material around the spigots, (v) On completion of the moulding cycle, deactivating the pressure means; retracting the spigot in the lid, and opening the lid of the die box, (vi) ejecting the finished block, supported on the base pallet, from the die box, and (vii) leaving the finished block to harden and dry.

16. A process for forming building blocks substantially as described herein with reference to the drawings.

17. A building block produced according to the process of any one of claims 11 to 16 having in the upper surface of the block a slot which extends from one end only part way.

18. A building block according to claim 17 wherein the slot extends halfway.

19. A building block substantially as described herein with reference to the accompanying drawings.