GB2063718A

GB2063718A - Sanding blocks of clay for making hand-moulded bricks

Info

Publication number: GB2063718A
Application number: GB8035269A
Authority: GB
Original assignee: Mattijssen Bv Maschf
Current assignee: Mattijssen Bv Maschf
Priority date: 1979-11-01
Filing date: 1980-11-03
Publication date: 1981-06-10
Also published as: BE880051A; NL7908028A; DE3041378A1

Abstract

Blocks of clay are sanded in the manufacture of hand-moulded bricks, by moving the blocks on a conveyor belt (1), (20), a portion of which periodically exhibits a sloping part (at rollers (6), (11) or (24) where the blocks are tipped in a direction opposite to the direction of movement of the belt. in the embodiment of Fig. 4, the blocks are tipped by reverse movement of the belt (20). <IMAGE>

Description

SPECI FICATION Method and apparatus for sanding blocks of clay or like material, for making handmoulded bricks This invention relates to a method of sanding blocks of clay or like material for the manufacture of hand-moulded bricks, in which such blocks are moved on a conveyor belt, sand is supplied to said conveyor belt, and means are provided for tipping the blocks.

In such a method, which is known for example from our Dutch patent application 75,14081, the tipping of the blocks is effected by a plurality of successive abutment members disposed above the conveyor belt for pivoting movement about axes parallel or substantially parallel to the upper run of the conveyor belt, the end of each abutment member away from said axis having the shape of a hook. Such a method, however, by no means satisfies the requirement of being productive of properly sanded blocks independently of the consistency of the blocks, their composition, moisture content, etc. Moreover, the residence time of the blocks on the conveyor belt is not the same for successive blocks.

It is an object of the present invention to remedy the disadvantages mentioned.

According to the invention, therefore, the method is characterized in that at least a portion of the belt is periodically moved in such a manner that in a sloping portion of the track the blocks of clay are tipped oppositely to the direction of movement of the belt.

The blocks may be tipped in a steeply sloping belt track portion, in which the belt moves upwardly. The steeply sloping portion of the track may be obtained by periodically effecting a difference in height in a normally horizontally extending track. As a consequence, each block is tipped during the passage of this portion in a direction opposite to the direction of movement of the conveyor belt.

Another solution is formed in the inclusion in the belt track of at least one portion sloping steeply downwardly, and moving the conveyor belt periodically in a direction opposite to the direction of transport. Naturally, the two methods may be fully or partially combined.

Yet another solution is formed by incorporating in the belt track one or more portions sloping steeply downwardly, which are moved in a direction opposite to the direction of movement of the belt.

The invention further relates to an apparatus for sanding blocks of clay or like material for the production of hand-moulded bricks, comprising at least one conveyor belt, means for tipping a block during its movement on the conveyor belt, and means for supplying sand to the block supply side. According to the invention this apparatus is characterized in that the means for tipping the clay block consist of means locally acting on the upper run of the conveyor belt for moving a portion thereof periodically out of its track.

Such means may take the form of rollers movable up and down and arranged on opposite sides above the upper run of the conveyor belt, and guide rollers disposed in front of and behind said rollers below the upper run of the conveyor belt, as viewed in the vertical direction.

By making the length of stroke of the reciprocating rollers in the vertical direction adjustable, the "sag" periodically formed in the belt by these rollers may be made deeper or less deep, whereby the tipping of the block in such "sag" may be influenced.

The tipping movement may be influenced further by making at least the guide roller disposed on the downstream end adjustable in horizontal direction.

Furthermore, below the lower run of the conveyor belt, at least one roller may be disposed which corresponds in diameter to said two rollers disposed on opposite sides of the upper run of the conveyor belt, which roller together with the rollers last-mentioned is periodically movable upwardly and downwardly. It is thus achieved that no slack is formed in the conveyor belt.

The rollers referred to may all be journalled on the end of an arm or bridge member rotatable by means of a piston-and-cylinder assembly or the like, the other end of which arm of bridge member is pivoted to, for example, the frame of the conveyor belt.

In a further elaboration of the invention, in order to limit the dimensions of the clay block, which swells during the tipping, the transverse spacing between the rollers disposed on opposite sides above the upper run of the conveyor may be adjustable. These rollers have at the same time the function of orientating the block of clay.

Naturally, the conveyor belt may have more than one portion which is movable out of the plane of the upper run of the conveyor belt, between which portions retainining means, such as a roller with a vertically arranged shaft, may be arranged above the conveyor belt. The result is that the block of clay which has passed the first "sag", is rotated through 90 , whereby it is ensured that during its passage of the second "sag" the end faces of the block are sanded.

A second sand supply device may be provided above the conveyor belt for the second reciprocating portion, as viewed in the downstream direction. It is thus ensured that sufficient sand is supplied in a regular manner to the second "sag" as viewed in the downstream direction.

In a further elaboration of the invention, the rollers on upstream and downstream side may be arranged so as to be spaced different transverse distances from each other. Thus the downstream rollers may be spaced apart a distance corresponding in essence to the long side of the mould into which the thus sanded blocks must be thrown.

Instead of a conveyor belt having more than one portion movable out of the plane of the upper run of the belt, use may be made of at least two conveyor belts arranged one after the other, or disposed at an angle relative to each other, each of said conveyor belts having a portion that is movable out of the plane of the upper run of the conveyor belt, with a roller with a vertical axis being disposed above one of the conveyor belts between the two portions movable upwardly and downwardly, and a second sand supply device being provided above the second conveyor, as viewed in the downstream direction.

In order that a correct amount of sand may be supplied, the device or devices for supplying sand may be adjustable. It is thus ensured that during the tipping of the block of clay in the "sag" the block falls into a correct sand bed, and is thus sanded in the correct manner. This is necessary because when there is an excess of sand, too much sand adheres to the block, owing to which too deep a "grain" is formed, and also a great loss of sand will occur. On the other hand, too little sand must not be supplied, as this will result in no substantial "grain" or no "grain" being formed at all.

In a further elaboration of the invention, the velocity of the conveyor belts is adjustable, so that the number of tippings of the clay block in the "sag" per unit of time may be adjusted.

The formation of "grain" during the sanding may be further influenced by providing the conveyor belt or belts with a profiled surface.

Another solution for tipping the blocks is obtained when the means acting locally on the upper run of the conveyor belt consist of rollers engaging with the belt, namely, rollers disposed on opposite sides above the belt and guide rollers disposed in front of, and behind, said rollers below the belt, secured to a chain conveyor movable in a direction opposite to the direction of movement of the belt.

An entirely different solution is achieved when, starting from an apparatus comprising at least one conveyor belt, means for tipping the clay block during its passage of the path of transport, and means for supplying sand to the block supply side, the arrangement is made such that the upper run of the conveyor belt has a stepped configuration, the belt is arranged to be periodically moved in a direction opposite to the direction of transport, and a sand supply device is provided over each step of the upper run of the conveyor beit.

The invention accordingly provides a method and apparatus for sanding blocks of clay with which good results are obtained independently of the consistency etc. of the blocks of clay. In addition, the apparatus requires a low structural height, so that it presents no problems with regard to its incorporation in existing apparatus for mixing clay, separating portions thereof, sanding the blocks of clay, and subsequently throwing the sanded blocks of clay into the moulds. Furthermore, it can be readily adapted to blocks of different dimensions.

Some embodiments of the apparatus for sanding blocks of clay according to the present invention will now be described with reference to the accompanying drawings, in which Figure 1 is a plan view; Figure 2 a side-elevational view of a first embodiment; Figure 3 a plan view of a second embodiment; Figure 4 a side-elevational view of a third embodiment; and Figure 5 a side-elevational view of yet another embodiment of the apparatus according to the present invention.

Referring to Figs. 1 and 2, there is shown an apparatus for sanding blocks of clay, comprising a conveyor 1 mounted on a frame 2.

A conveyor belt 5 runs in the direction indicated by arrows over a roller 3, driven by a pulley 17, and a reversing roller 4. Furthermore, a plurality of guide rollers 6, 7, 8 and 9 are provided on the conveyor. Guide roller 6 is adjustable in a horizontal direction by means not shown. Arranged above the upper run of the conveyor belt, in spaced relationship to each other, are two felt-covered rollers 10 and 11, which are mounted on a bridge member 1 2. This bridge member, which is rotatable about a shaft 1 3 also mounts a roller 14 which extends below the lower run of the conveyor belt.

Bridge member 1 2 is engaged by the piston rod of a piston-and-cylinder assembly 1 9 controlled by means not shown, and by means of which the bridge member, and hence the rollers can be periodically moved upwardly and downwardly, during which movement no slack is forked in the conveyor belt. As appears from Fig. 2, the frame of the conveyor is provided with guide slots 1 5 for guiding the shafts of the rollers. It will be clear that the size of the stroke of the piston-andcylinder assembly may be adjustable, whereby the "depth" of the "sag" formed by rollers 11 from time to time may be adjusted: a change of this depth may be necessary, for example, when the size of the clay blocks is changed. The adjustability of guide rollers 6 may also provide for adjustment of the slope, i.e. the angle with the horizontal of the downward portion of the "sag", whereby the tipping moment of the clay block may be af fected.

In fact, this tipping movement cannot occur until after a correct sand bed has again been formed. This sand bed is produced by means of an adjustable vibratory chute 1 6 arranged on the upstream side above the conveyor belt (for the sake of clarity chute 1 6 is not shown in Fig. 1). The chute is adjustable with regard to both the dosage per unit of time and the dosage time, so that any sand bed suited to the material to be processed can be produced.

It is further observed that the felt-covered rollers 10 and 11 are adjustable relative to each other in the transverse direction by means not shown. By virtue of this arrangement, the swelling of the clay blocks which occurs during the tipping is limited. These rollers also serve to orientate the clay blocks, so that during further transportation over the conveyor belt, i.e. after rollers 10, 11 and 14 have been moved upwardly, these are in the proper position on the belt.

The apparatus described hereinbefore only provides for sanding-and during the tipping the formation of a "grain" or folds-on four circumferential surfaces of the block of clay.

For sanding the two other surfaces, two of the apparatuses shown in Figs. 1 and 2 are placed one behind the other, as indicated in plan view in Fig. 3. It is clear that the apparatuses may be disposed at an angle to each other, or even one below the other.

The apparatus shown in part in the righthand portion of Fig. 3 corresponds in essence to that shown in Fig. 1. Th apparatus shown in the left-hand portion of Fig. 3 (above which the sand supply device has been omitted) differs in essence on two points only relative to that shown in the right-hand portion of Fig.

3 (indeed, similar parts are designated by the same reference numerals). In the first place, there is provided above the conveyor belt, in the path of movement of the block of clay, a roller 1 8 disposed with its axis in the vertical direction, which roller serves for rotating the supplied, partially sanded block of clay through 90 . When, as stated above, the apparatuses are disposed at an angle to each other (in this case an angle of 90 ) roller 1 8 may be omitted. It is clear, however, that other means may be applied for rotating the block of clay through 90 .

Furthermore, the felt-covered rollers 10 and 11 of the apparatus are spaced a larger distance apart than the corresponding rollers of the upstream apparatus. This larger spacing may be in accordance with the longitudinal dimension of the mould.

It will be clear that, instead of two separate belts, a single belt may be used. In connection with the exchangeability, or replacement, the use of separate belts is, however, preferred. It is also possible to arrange more than two belts one behind the other, so that the number of blocks to be sanded per unit of time may be increased.

As stated before, the number of tipping movements, and hence the degree of sanding and grain formation of the blocks of clay in the "sag" per unit of time can be changed by changing the velocity of the belt.

Another manner of affecting the grain formation is formed by using a conveyor belt having a profiled surface.

It is observed that a large number of modifications and changes are possible without departing from the scope of the invention. Thus, for example, instead of rollers 11, guide roller 6 may be moved periodically up and down for forming the "sag" contemplated.

In the embodiment shown in Fig. 4, unlike the embodiments described hereinbefore, a "sag" is not used, but the conveyor has two fixed, steeply sloping belt track portions. For this purpose the apparatus is provided with a conveyor belt 20 trained over reversing rollers 21 and 22. One of these rollers is driven by means not shown. As is further apparent from Fig. 4, there are provided a plurality of guide rollers 23. Disposed directly downstream of the guide rollers, in spaced relationship to each other, are two rollers 24 (comparable to rollers 10 and 11 in the embodiments described hereinbefore), in such a manner that each time a steeply sloping belt track portion is produced. In operation, as soon as a block of clay has passed a guide roller 23 and fallen between rollers 24, the direction of movement of the conveyor belt 20 is reversed.As a result the block of clay will be tipped. In order to ensure that the block of clay falls into a sand bed, a vibratory chute 25 for supplying sand is arranged downstream of rollers 24. As there must also be a sand bed at the supply end of the conveyor belt, under a block supply belt 28, there is here provided a similar vibratory chute 26.

As appears further from Fig. 4, a roller 27, comparable to roller 1 8 in Fig. 3, is provided downstream of the first steep portion above the conveyor belt for rotating a block of clay through approximately 90 . It is thus ensured that the end faces of the block are also sanded. Here again, modifications may be made without departing from the scope of the inventive idea. Moreover, the various embodiments may be fully or partially combined.

In the embodiment shown diagrammatically in Fig. 5, use is made of a plurality of "sags" which move along the upper run. For this purpose the latter is provided with a conveyor belt 29 trained over reversing rollers 30 and 31. Each "sag" is formed by two spaced, feltcovered rollers 32 and a guide roller 33, 34, respectively disposed in front of, and behind the same. These rollers are secured to two chains 35 mounted on opposite sides of the belt and arranged to be driven in a direction (see the arrow designated by 36) opposite to the direction of movement (see arrow 37) of the belt. The chains may be moved periodically or in synchronism with the hand-moulding plant of which the apparatus forms part.

In this embodiment, too, of course, all sorts of adjustment facilities are provided in order that the apparatus may be adapted to prevailing conditions.

Claims

1. A method of sanding blocks of clay or like material for the manufacture of handmoulded bricks, in which such blocks are moved on at least one conveyor belt, sand is supplied to said conveyor belt, and means are provided for tipping the blocks, using a difference in height in the transportation track, characterized in that at least a portion of the belt is periodically moved in such a manner that in a sloping portion of the track the blocks of clay are tipped oppositely to the direction of movement of the belt.

2. A method as claimed in claim 1, characterized in that the blocks are tipped in a steeply sloping belt track portion, in which the belt moves upwardly.

3. A method as claimed in claim 2, characterized in that the steeply sloping portion of the track is obtained by periodically effecting a difference in height in a belt track portion normally extending horizontally.

4. A method as claimed in claim 1 or 2, characterized by the inclusion in the belt track of at least one portion sloping steeply downwardly, and moving the conveyor belt periodically in a direction opposite to the direction of transport.

5. A method as claimed in claim 1 or 2, characterized by incorporating in the belt track one or more portions sloping steeply downwardly, which are moved in a direction opposite to the direction of movement of the belt.

6. Apparatus for sanding blocks of clay or like material for the production of handmoulded bricks, comprising at least one conveyor belt, means for tipping a block during its traversal of the transportation track, and means for supplying sand to the block supply side, characterized in that the means for tipping the clay block consist of means locally acting on the upper run of the conveyor belt for moving a portion thereof periodically out of its track.

7. Apparatus as claimed in claim 6, characterized in that said means consist of rollers movable up and down and arranged on opposite sides above the upper run of the conveyor belt, and guide rollers disposed in front of and behind said rollers below the upper run of the conveyor belt, as viewed in the vertical direction.

8. Apparatus as claimed in claim 7, characterized in that the length of stroke of the reciprocating rollers in the vertical direction is adjustable.

9. Apparatus as claimed in claim 7 or 8, characterized in that at least the guide roller disposed on the downstream end is adjustable in horizontal direction.

10. Apparatus according to claim 7, 8 or 9, characterized in that below the lower run of the conveyor belt, at least one roller is disposed which corresponds in diameter to said two rollers disposed on opposite sides above the upper run of the conveyor belt, which roller together with the rollers last mentioned is periodically movable upwardly and downwardly.

11. Apparatus according to claim 9, characterized in that the rollers above the upper run and the roller below the lower run are journalled on the end of an arm or bridge member rotatable by means of a piston-andcylinder assembly or the like, the other end of which arm of bridge member is pivoted to, for example, the frame of the conveyor belt.

1 2. Apparatus as claimed in any of claims 7-11, characterized in that the transverse spacing between the rollers disposed on opposite sides above the upper run of the conveyor is adjustable.

1 3. Apparatus according to any of claims 6-12, characterized in that the conveyor belt has more than one portion which is movable out of the plane of the upper run of the conveyor belt, between which portions retaining means, such as a roller with a vertically arranged shaft, is arranged above the conveyor belt.

14. Apparatus according to claim 13, characterized in that a second sand supply device is provided above the conveyor belt for the second reciprocating portion, as viewed in the downstream direction.

1 5. Apparatus according to claim 1 3 or 14, characterized in that the rollers on the upstream and downstream side are arranged so as to be spaced different transverse distances from each other.

16. Apparatus according to any one of claims 6-11, characterized by at least two conveyor belts arranged one after the other, each of said conveyor belts having a portion that is movable out of the plane of the upper run of the conveyor belt, with a roller with a vertical axis being disposed above one of the conveyor belts between said two portions movable upwardly and downwardly, and a second sand supply device is prcvided above the second conveyor, as viewed in the downstream direction.

1 7. Apparatus according to any one of claims 6-16, characterized in that the device or devices for supplying sand are adjustable.

1 8. Apparatus according to any one of claims 6-17 characterized in that the velocity of the conveyor belts is adjustable.

1 9. Apparatus according to any of claims 6-18, characterized in that the conveyor belt or belts is or are provided with a profiled surface.

20. Apparatus according to claim 6, characterized in that the means acting locally on the upper run of the conveyor belt consist of rollers engaging with the belt, namely, rollers disposed on opposite sides above the belt and guide rollers disposed in front of, and behind, said rollers below the belt, secured to a chain conveyor movable in a direction opposite to the direction of movement of the belt.

21. Apparatus for carrying out the method of claim 4, comprising at least one conveyor belt, means for tipping the clay block during its passage of the path of transport, and means for supplying sand to the block supply side, characterized in that the upper run of the conveyor belt has a stepped configuration, the belt is arranged to be periodically moved in a direction opposite to the direction of transport, and a sand supply device is provided over each step of the upper run of the conveyor belt.

22. A method of sanding blocks of clay or like material for the manufacture of handmoulded bricks, substantially as hereinbefore described.

23. An apparatus for sanding blocks of clay or like material for the production of hand-moulded bricks, substantially as hereinbefore described with reference to Figs. 1 and 2, Fig. 3, Fig. 4, or Fig. 5 of the accompanying drawings.

24. Hand-moulded bricks whenever manufactured from blocks of clay sanded by a method or in an apparatus according to any preceding Claim.

25. The features herein described, or their equivalents, in any novel selection.