GB2161416A

GB2161416A - New pre-stressed cattle slat production system

Info

Publication number: GB2161416A
Application number: GB08417421A
Authority: GB
Inventors: John Finlay
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-07-07
Filing date: 1984-07-07
Publication date: 1986-01-15
Also published as: GB8417421D0

Abstract

A production system using the extrusion method to produce Pre-Stressed cattle slats with an improved quality finish on the top surface. This is achieved by casting the slat upside down in a specially profiled bed. Self spacing heads can then be added, or cross bridges, to produce gangs without affecting the quality of the top of the slat. Figure 8 illustrates the finished product as single slats. They have a level non slip 12 surface of either chequered or indented pattern. They have rounded edges 13 on the top surface and a fixed spacing 14 between slats. The height of slats can be maintained constant 11 which makes matching of slats in double rows a simple operation. <IMAGE>

Description

SPECIFICATION New pre-stressed cattle slat production system This invention relates to an improved system of manufacturing Pre-Stressed Cattle Slats which facilitates the addition of self spacing heads and the production of Gang Slats.

The present method uses a machine made by Messers Max Roth K.G. West Germany. This machine extrudes eight slats per pass on a flat bed.The slats are cast as shown in the section Figure 1. In service slats require to be spaced out at approximately 40 mm apart to allow the dung to pass through. Because the original German machine produced slats of a constant cross section, the slats produced by it had to be laboriously built into position at the required spacing.

In 1982 John Finlay (Engineering) Ltd., developed a machine to add self spacing heads of concrete moulded into the plain extruded slat. While this machine produced slats which were self spacing in service, the slats suffered from the following problems of quality.

The addition of the head to the freshly extruded slat caused distortion to the slat especially on the top where a level surface is necessary fo the comfort of animals which have to live on the slatted floors.

The shape of the extruded slat made it difficult to place and compact the semi-dry concrete to form the "heads" and consequently heads were liable to break off.

Because the extruded slats varied in height and width 18 depending on the moisture content of the concrete mix used to produce them it was difficult to match the slats on tanks requiring two or more rows and the spacing between slats was not consistent.

The German machine sometimes produced "drag" cracks on the top surface of the extruded slat. Slats with these cracks were "second" quality.

The top surface of the freshly extruded slats were easily damaged by the covers used to insulate them during curing.

To overcome the above problems of quality the present invention proposes to change the method of manufacture as follows. The Roth machine would extrude the slats upside-down unto a specially profiled bed. Self spacing heads would then be added to the freshly extruded slats giving either single or gang slats.

The top surface of the slat is that part which is cast into the profiled bed. It is therefore of consistent quality and is not affected by the addition of the head.

The profiled bed is so shaped as to produced rounded corners on the top of the slat. This will not damage cattle feet. Also a non slip feature is built into the profiled bed by using chequer or indented plating for the floor of the mould.

Because the spacing of the slats is dictated by the profile of the bed consistency should be guaranteed irrespective of the moisture content of the mix used to produce the slats.

The new machine will add a head of constant height consequently when placing double rows of slats they should match for height.

The section of the proposed slat should lend itself for easier passage of the dung and hence cleaner slats.

It will be possible to produce "Gang slats" i.e.

two or four slats joined at each end and at the centre span. This will enable longer slats and consequently less cluttered tank space under the slats since centre support walls will not be necessary in some tanks.

A specific use of the invented system to produce self spacing single slats is described in the following example in which: Figure 2 shows a section through the slats as extruded by the "Roth" machine.

Figure 3 shows a section with the mould in place for forming the self spacing heads.

Figure 4 shows a section of the mould filled with concrete mix using mould vibration to eliminate voids.

Figure 5 shows a section illustrating the first stage compaction of the head using the special tamper head.

Figure 6 shows a section of the second stage filling.

Figure 7 shows a section of the final compaction of the head using the tamper head.

Figure 8 shows a section of the finished slat in its service position.

Figure 9 shows a plan of the finished slats.

Referring to the drawings Figure 2 shows a section through the proposed bed of slats which are cast upside-down 4. The floor part of the mould 1 is made from a chequer or indented plate to produce a non-slip top surface to the slat. The profiled part 3 provides the fixed spacing between the slats. The bottom corners 2 are radiused to produce rounded edges on the top of the slats.

Figure 3 shows a section of the mould placed over the freshly extruded slats to add the heads.

The mould can be placed at any position along the length of the extruded slats depending on the length of slat required. The mould produces heads which are approximately 200 mm long. When the slats have cured these heads are then cut mid-way 5 to produce 100 mm long heads at each end of every slat. Figure 9.

In Figure 4 we see concrete of the same mix as the slat filled into the mould using mould vibration to eliminate voids.

Figure 5 shows the first stage compaction of the concrete to form the heads. The special two stage tamper head has the side members extended 6 so that only the concrete on either side of the slat is compacted 7. This compaction is achieved by using vibration and pressure from the tamper head.

The concrete bonds to the freshly extruded slat to form a homogeneous mass.

Figure 6 shows a section of the second stage filling 9. The tamper head is raised clear of the mould 8 to allow filling.

Figure 7 shows a section of the second stage compaction of the head. The side members of the tamper head 10 are raised to produce a flat tamper. The level to which the tamper compacts the concrete is fixed 11 and thus the heads are always the same height. After compaction of the head the mould and then the tamper head are removed vertically.

Figure 8 shows a section through the slats in service. The top will have a non slip chequered or indented surface 12. The edges will be rounded 13.

The spacings between the slats will be consistant 14.

A specific use of the invented system to produce Gang Slats is described in the following example in which: Figure 2 again shows a section through the slats as extruded by the "Roth" machine.

Figure 10 shows a section of the extruded slat with the cross reinforcement in position.

Figure 71 shows a section with the mould in position for forming the cross "bridges" of the gangs.

Figure 12 shows a section with the mould filled with concrete mix.

Figure 13 shows a section of the first stage compaction.

Figure 14 shows a section of the second stage filling.

Figure 15 shows a section of the second stage compaction.

Figure 16 shows a section of the finished gang slat in service.

Figure 17 shows a plan of the finished gang sl:t.

Referring to the drawings.

Figure 2 shows a section through the proposed bed of slats as in the previous example. The cross reinforcement 15 is then placed. Pairs of bars are placed at the positions where the cross bridges are to be formed. Figure 10.

Figure 11 shows the gang mould be placed in position over the reinforcement to form the cross bridges. The mould is placed depending on the length of gang required. The bridge produced are 200 mm long 16 and alternate bridges are cut midway to produce gangs with 100 mm bridges at either end and 200 mm bridges in the centre. Figure 17.

Figure 12 shows a section of the mould filled with concrete using mould vibration to eliminate voids.

Figure 13 shows the first stage compaction of the concrete to form the bridge. The two stage tamper head has its side members extended 6 so that only the concrete on either side of the slats is compacted 7. The extended side tampers also push the cross reinforcement to the required level within the heads 17. Tamper vibration and pressure are used to perform these functions. The concrete of the bridge bonds with the freshly extruded slat to form a homogeneous mass.

Figure 14 shows a section of the second stage filling operation. The tamper head 8 is lifted clear to allow filling 9.

Figure 15 shows a section of the second stage compaction. The tamper side members are raised 10 to produce a flat surface on the tamper. Compaction using vibration and pressure on the tamper is then carried out to the fixed level 11. The mould and then the tamper are then removed vertically.

Figure 16 shows a section through the gang slat in service. We have the non slip top surface 12 which can be either of chequered or indented pattern, the rounded edges 13 and the fixed spacing between slats 14.

Claims

1. A new prestressed cattle slat production system where the slats are extruded upside down on a specially profiled bed. This facilitates the addition of self spacing heads or cross bridges to form gangs without affecting the quality of the top surface of the slat.

2. A new prestressed cattle slat production system as claimed in Claim 1 wherein the floor of the profiled bed is chequered or indented to produce a non slip top surface to the slat.

3. A new prestressed cattle slat production system as claimed in claim 1 and 2 wherein the corners of the profiled bed are radiused to produce rounded top edges on the top of the cattle slats.

4. A new prestressed cattle slat production system as claimed in claims 1,2 and 3 wherein the profiled bed produces a fixed spacing between slats after the addition of the spacing heads or cross bridges.