In previously known manufacturing methods, such paint process- ing has usually been effected by the fact that the paint in question is sprayed into the different channels in fog form, e. g. by means of a conventional spray gun. However, this proc- essing technique does not provide a satisfying result inasmuch as the paint coating on the internal surfaces of the channels becomes irregular and at times non-existent. Furthermore, spraying of the paint is a time-consuming and troublesome work, and, what is more, it is environmentally loading for the opera- tor as well as for the surroundings. In addition, spraying fre- quently entails a waste of the paint. A particular drawback of spraying as an application method is that not only the surfaces of the through channels are coated with paint, but also large parts of the top and bottom sides of the masonry blocks. This makes the subsequent bricklaying work more difficult and dete- riorates the quality of the prospective brickwork inasmuch as the mortar does not adequately affix to the areas of the top and bottom sides of the blocks, respectively, which have been coated with paint.

Objects and Features of the Invention The present invention aims at obviating the above- mentioned drawbacks of previously known paint or liquid coating technique and at providing on one hand an improved method, and on the other hand an appropriate apparatus for application of paint or liquid onto surfaces within internal cavities in masonry blocks or other hollow objects. Thus, a primary object of the invention is to provide an apparatus in which all of the

internal cavities in the processing object are completely coated with liquid, while guaranteeing a regular coating. An additional object is to provide an apparatus in which the coat- ing work may be effected in a fast, convenient and environ- mental-friendly way. Yet another object of the invention is to provide an apparatus in which it is guaranteed that at least parts of the exterior of the object, e. g. the edge portions of the top and bottom sides of a masonry block, are with certainty not soiled with liquid. Another object of the invention is to provide an apparatus that utilizes the liquid or the paint in an optimum way, so far that every form of wastage is avoided.

Thus, the liquid should be able to circulate within a closed cycle and only be consumed by being applied to exactly the sur- faces, which are desired to be coated.

According to the invention, at least the primary object is attained by the features defined in the characteriz- ing clause of claim 1. Preferred embodiments of the apparatus according to the invention are furthermore defined in the dependent claims 2-7.

In a second aspect, the invention also relates to a liquid application method. The features of this method are seen in claim 8.

Brief Description of the Appended Drawings In the drawings: Fig 1 is a perspective view of an apparatus according to the invention, Fig 2 is an exploded view in perspective showing various components of the apparatus separated from each other, and Fig 3 is an enlarged planar view, illustrating the hole pattern of in a masonry block, which may advanta- geously be processed in the apparatus according to the invention.

Detailed Description of a Preferred Embodiment of the Invention In the various drawing figures, 1 generally desig- nates a masonry hole block, which is to be processed in the apparatus. This block is of a parallelepipedic basic shape and

has a top side 3 and a bottom side 4 in addition to four side surfaces 2. As may be seen in fig 3, channels 5 extend through the block, more precisely through-going from the top side 3 to the bottom side 4. Each such channel 5 is delimited by an internal surface designated 6. The purpose of the invention is to apply liquid, particularly reflecting paint, onto these sur- faces. The end surfaces of the partition walls and outer walls that define the channels 5 are designated 7. These end surfaces 7 should neither be soiled with paint on the top side nor the bottom side of the block.

In fig 2, the many channels or internal cavities have not been shown in detail, but only schematically indicated by means of an edge portion, designated 7.

Reference is now made to fig 1, in which it may be seen that first and second vessels 8,9 are included in the apparatus, as well as a trough 10, on top of which the block 1 is applicable. Of these vessels, vessel 8 constitutes a main vessel, while vessel 9 forms a secondary vessel, which is not absolutely necessary according to the invention. In the example the trough 10 is carried by a stand 11, more precisely on a frame 12, serving as an intermediate part, which is located approximately halfway between the upper and lower parts of the stand. The upper part of the stand consists of a second frame 13, that carries a pressing device, which in its entirety is designated 14.

As may be seen in fig 2, a rectangular, endless sup- port collar or support part 15, which is united to the upper edges of the trough 10, is included in the vessel 10. On the top side of the support part 15, an endless seal 16 is applied having the same rectangular basic shape as the support collar.

Said seal 16 consists of a material of an elastic, liquid- proofing character, such as rubber or the like. Although the support part 15 and the seal 16 have only been indicated as rectangular frames in fig 2, the same are in practice in the form of hole plates having the same hole pattern as the block in fig 3. Although the components 10,15, 16 are shown spaced- apart in fig 2, the same are in practice united to each other while forming a single integrated unit. In the bottom of the trough 10, there is a hole, which is indicated at 17 in fig 2.

In the illustrated, preferred example, this hole serves not only as an evacuation hole for liquid that is to run out of the trough 10, but also as an intake hole for liquid that is to be pressed up into the trough.

The pressing device 14 includes a stamp 18 in the form of a frame having a rectangular basic shape. Via a cross piece 19, this stamp is carried by a piston type cylinder mechanism 20, which in turn is fixedly mounted on a cross piece 21 in the upper frame 13 of the stand 11. More precisely, the cylinder of the mechanism is attached to the frame cross piece 21, while the piston rod of the mechanism is attached to the cross piece 19. By means of the piston type cylinder mechanism 20, the stamp 18 may move vertically between an upper position in which the block 1 may be inserted between the stamp and the trough, and a lower position in which the stamp keeps the block pressed and fixed against the trough.

On the bottom side of the stamp 18, a support part 22 is attached on the bottom side of which a second, endless seal 23 is arranged, which may be pressed against the edge portion 7 of the block 1. Like the details 15,16, the support part 22 and the seal 23 have the form of hole plates having the same hole pattern as the block according to fig 3.

In the apparatus, two pipes 24,25 are furthermore included, one of which, viz. the conduit 24, forms a feeder for supply of liquid from the main vessel 8 to the trough 10. The second conduit 25 constitutes an evacuation conduit via which excess liquid from the trough 10 may run back down into the main vessel 8. In the illustrated, preferred example, at which a secondary vessel 9 is included in the apparatus, the vessel 9 divides the feeder 24 into two branch conduits 26,27, the first-mentioned one of which extends between the vessels 8 and 9, while the last-mentioned branch conduit 27 extends between the vessel 9 and the trough 10. As clearly may be seen in fig 1, the vessel 9 serving as an intermediate storing vessel is placed on a considerable level above the trough 10. However, the first vessel or main vessel 8 is placed on floor level, i. e. below the vessel 10.

In the first branch conduit 26, a pump 28 is arranged by means of which liquid may be pumped up from the vessel 8 to

the vessel 9. In the second branch conduit 27, a valve 29 is arranged, preferably in the form of a cut-off valve, which per- mits flows of liquid to the trough in an open state, but shuts off said flow in a closed position. In the evacuation conduit 25, another cut-off valve 30 is arranged, which in an open po- sition permits that the excess liquid from the trough runs back down into the main vessel 8, but makes return flow of the liq- uid impossible in a closed position.

Function and Advantages of the Apparatus According to the Invention When a block 1 is to be processed in the apparatus, both of the valves 29,30 are suitably initially closed, in addition to which the stamp 18 of the pressing device is kept in an upper position. In this state, the block 1 may be in- serted between the stamp and the trough 10, and then the block is fixedly pressed against the trough by supply of compressed fluid, preferably compressed air, to the cylinder of the mecha-. nism 20. The clamping of the block is carried out in such a way that the end surfaces 7 on the bottom side of the block are pressed so that the hole pattern in the block corresponds to the hole pattern of the seal 16, so that liquid may ascend into the channels 5. In an analogous way, the seal 23 is pressed with the hole pattern fit against the top side of the block.

This means that the channels in the block are upwardly open (whereby the air in the channels may unresistingly be evacuated when the liquid ascends in the channels).

It should be pointed out that a certain quantity of liquid is always stored in the upper vessel 9 after being pumped up from main vessel 8 (something that advantageously, though not necessarily, is carried out in batches or intermit- tently).

In the next step, the valve 29 is opened at the same time as the valve 30 is still kept closed. By the level differ- ence between the vessel 9 and the block 1, liquid from the ves- sel 9 may be pressed up through the hole 17 in the trough by means of gravity and ascend up in the channels 5 in the block 1. When the liquid has ascended up to the top side of the block, which may be stated ocularly, the valve 29 is closed.

After the desired dwell time (e. g. some second or seconds) for the liquid in the channels, the valve 30 is opened, which re- sults in the liquid running back to the main vessel 8 via the evacuation conduit 25.

When the channels in the block have been emptied, the valve 30 is closed again, and the stamp 18 is lifted up a dis- tance by means of the mechanism 20, so that the block freely may be removed from the trough. After this, the apparatus is ready for a new processing cycle, which is carried out in the same way.

The process method that is carried out in the appara- tus thus includes the steps of bringing the liquid to ascend upwards in the internal cavities of the process object from a bottom side towards a top side in order for the liquid to stick on the delimiting surfaces of the internal cavities, and excess liquid in the channels being allowed to run out in the direc- tion downwards through the cavities. Therefore, by the inven- tion, it is guaranteed that the liquid is completely brought into contact with the entire delimiting surface in the individ- ual internal cavity, which ensures an even and reliable liquid or paint coating on the surfaces. Furthermore, the process may be carried out in a fast and convenient way without environ- mental detriment for the operator. By the existence of the described seals, it is furthermore guaranteed that the top and bottom sides of the block or of the object are not soiled with paint or liquid. Therefore, if the block is used for bricklay- ing purposes, it is guaranteed that mortar in a reliable way adheres to said surfaces.

Feasible Modifications of the Invention The invention is not solely restricted to the example described above and illustrated in the drawings. Thus, it is feasible to spare the particular intermediate storing vessel, more precisely by directly connecting the main vessel to the trough, a pump in the feeder pumping up paint or liquid with a certain pressure into the internal cavity, the pumping being interrupted when the liquid has reached the top side of the object. It should also be mentioned that the two vessels may be either open or closed. Although the described embodiment of the

apparatus according to the invention is intended for applica- tion of paint on internal surfaces in the process object, the apparatus may also be utilized for other, similar purposes. For instance, it is feasible to in the described way use other liq- uids, such as detergents, etching solutions, oil or the like, for providing a complete finish of arbitrary type.