DEVICE FOR THE CONVEYANCE OF PASTY MATERIAL

Abstract: A device for the conveyance of pasty material is described, which is in particular suitable for the printing of materials, comprising at least one stock container (3) for the pasty material, a pump (1) provided with a pump feed and pump discharge, and distribution means, wherein the stock container (3) is provided with an outflow aperture (5) which can be connected directly to the pump feed and which in the operating position for the removal of pasty material from said stock container forms essentially the lowest level of the stock container. Said outflow aperture (15) can be provided near the bottom (6) of the container, or can be disposed in a removable, preferably sloping cover (8) of the stock container, said cover being provided with an air suction opening (10). The outflow aperture (5) of the stock container (3) can also be disposed in a removable bottom part (30) of the stock container, said part being provided with coupling elements (31, 35) for connecting the pump feed to the stock container (3).

Description: The invention relates to a device for the conveyance of pasty material, comprising at least one stock container for the pasty material, in addition to at least one pump provided with a pump feed and pump discharge, and distribution means for the pasty material, in particular suitable for the printing of materials. Such a device is generally known per se. This known device can be operated in a simple manner, and the stock container can be changed quickly. Moreover, no special requirements need be set for the stock containers, while no valves are required in the suction line. The disadvange of this known device is, however, that a fairly long suction line is present between the stock container and the pump. A fairly high paste loss therefore occurs through pasty material remaining behind in the container and in the suction line. The suction line must also always be cleaned internally and externally after use of a stock container. A device in which the disadvantages inherent in the use of a suction line are eliminated has now been found. The invention therefore relates to a device for the conveyance of pasty material of the above-mentioned type, which is characterized in that the stock container is provided with an outflow aperture which can be connected directly to the pump feed, and which in the operating position for the removal of pasty material from the stock container forms essentially the lowest level of the stock container. In the device according to the invention there is therefore no suction line at all between a stock container and the pump. The outflow aperture of the stock container is prefarably provided near the bottom of the container. The bottom of the stock container is expediently provided with a recess near the outflow aperture of the container. The bottom of the stock container can also particularly advantageously run sloping in the direction of the outflow aperture. Such a positioning of the outflow aperture and shaping of the bottom of the stock container leads to less loss of the pasty material, due to the fact that the pasty material can be drawn virtually completely out of the container. The absence of a suction line also means that no suction of air from such a line takes place, which means that less rejection will take place during the printing of materials with the pasty material. Since, in addition, only the pump has to be cleaned after use of a container, this results in a shorter washing time with less water consumption than is the case in the known devices with a suction line. The stock containers to be used therefore have a bottom which is of a particular shape. This can, however, be a problem because the connection of the outflow aperture to the pump feed is more complicated, since this aperture is now situated near the bottom of the container. In order to eliminate such a problem, the outflow aperture of the stock container can be disposed in a removable, preferably sloping cover of the stock container which is provided with an air suction aperture. Such a cover can be fixed on the stock container by means of, for example, a strap clamp closure which is known per se. Such a solution has the additional advantage that the stock containers need not be of any particular shape, and the usually used containers are suitable, while the washing equipment for washing the stock containers after their use do no require any adaptations either. The device is expediently provided with tilting means for tilting the stock container. The pump is also preferably provided with coupling elements for connecting the pump feed to a container with cleansing fluid. The coupling elements are expediently also provided with a shut-off element which may or may not be controlled automatically, preferably a three-way valve which can be connected to a feed of pasty material or a feed of cleansing fluid, on the one hand, and to the pump feed, on the other. More particularly, the coupling elements are detachably connected to a preferably sloping cover of the stock container provided with an outflow aperture, said outflow aperture being connected directly to the pump feed. The outflow aperture of the stock container can according to an expedient embodiment of the invention be disposed in a removable bottom part of the stock container, said part being provided with coupling elements for connecting the pump to the stock container. The removable bottom part is then preferably provided with a shut-off element, which may or may not be controlled automatically, in particular a shut-off valve. In order to quarantee a good fixing, the removable bottom part is also provided with locking means which can mate with means for opening the shut-off element, said means being detachably connected to a pump feed. The invention will be explained in greater detail with reference to the appended drawing, in which: Fig.1 shows a known device for the conveyance of pasty material; Fig. 2 shows a device according to the invention with a container of the usual shape; Figs. 3 to 5 show containers of adapted shape which are usable according to the invention; Fig. 6 shows the same device as that shown in Fig. 2, but provided with tilting means; Fig. 7 shows a container of the usual shape provided with a cover according to the invention; Figs. 8 and 9 show means for cleaning the pump; Fig. 10 shows means for cleaning a cover according to Fig. 7; Fig. 11 shows a container of the type shown in Fig. 7, provided with a suitable tilting platform; Fig. 12 shows a container provided with a removable bottom part; and Fig. 13 shows an expedient pump connection for a container of the type shown in Fig. 12. Fig. 1 shows a known device for the conveyance of pasty material comprising a pump 1, which is provided with a suction line 2 which is connected to the pump feed, and through which the pasty material is drawn out of container 3 and conveyed. Via line 4, which is connected to the pump discharge, the pasty material is pumped to distribution means which are particularly suitable for the printing of materials. The fairly long suction line does, however, result in additional paste loss, while the line itself has to be cleaned internally and externally after use. Figs. 2 to 6 show a number of preferred embodiments of suitable stock containers according to the invention. What is essential according to the invention is that the pump feed is directly connected to the stock container. Of course, containers of a different shape can also be used near the outflow aperture, provided that, of course, the outflow aperture in the operating state for the removal of pasty material from the stock container essentially constitutes the lowest level of the stock container. In the embodiment shown in Fig. 2 the shape of the stock container 3 is essentially that of the known container. The outflow aperture 5 is near the bottom of the container. In order to make the outflow of pasty material out of the container take place as completely as possible, the container according to Fig. 2 can be provided with tilting means 7, as can be seen in, for example, Fig. 6. Figs. 3, 4 and 5 show embodiments in which the bottom 6 of the stock container is modified in such a way that the pasty material present in the container can be removed virtually completely. The use of the stock containers according to the invention also means that no loss of pumping capacity occurs, through the fact that there are no suction lines at all. On other hand, it is possible to provide the stock container 3 with a removable cover which is provided with an outflow aperture. This variant is shown in Fig. 7. The cover 8 is removably disposed on container 3; and it is preferably sloping. Although the known stock containers are of a conical shape, containers of a different shape can, of course, also be used. The cover 8 is provided with outflow aperture 5 and air suction aperture 10. The cover can be fixed on the container by means of a clamp strap closure 9, which is known per se. The cover with the container is therefore directly connected to the suction side of the pump; in the operating state for the removal of pasty material from the stock container, this container rests on the fixed support 11. In order to clean the pump after use, the pump is also provided with coupling elements 13 (see Fig. 8), so that the pump can be coupled to flushing head 12. The pump can be cleaned with cleansing fluid 19 via suction line 14 and possibly additional air injection 15. The coupling elements are preferably also provided with a shut-off element, which may or may not be automatically controlled, such as three-way shut-off valve 17 (see Fig. 9), which can be connected at one side to the feed 16 of pasty material or a feed 14 of cleansing fluid. Additional air injection can take place if necessary via 15. Fig. 10 shows a variant which is particularly suitable for cleaning the device according to the invention where a cover of the type shown in Fig. 7 is used. The cover 8 can remain connected to the pump here, if the stock container of the pasty material is empty, and can be connected directly to the flushing head 18 by means of, for example, clamp strap 9. The pump can then be cleaned with cleansing fluid via suction line 14, together with the cover of the stock container connected thereto. If desired, the operation can be controlled automatically, possibly with air injection via 15. Fig. 11 shows an embodiment of a stock container according to Fig. 7, in which the stock container is provided with a tilting platform 22, 23. The stock container 3 can be placed in position on part 8 thereof, and can be fixed on the platform by means of side arms 24 and elastic closure 20. When the contents have been removed from the stock container, it can be cleaned by pumping back any polluted fluid from the collection system 19 via delivery line 14, or cleansing fluid via connection 27, possibly with air injection via 15. The cleansing fluid flows out of pump connection 25 and via grilles 26 to the collectionsystem 19 for polluted fluid. Fig. 12 shows a special variant of a stock container, in which the outflow aperture of the container is disposed in a removable bottom part 30, which is provided with coupling element 31, 35. The pressure piece 35, as shown at "A" is adequate for containers with a strong enough bottom and base 36. If the container does not have a sturdy base, the pressure piece can be combined with a raised bottom part 37, as shown in "B" in Fig. 12. Nut 38 is used to fix the bottom part completely in the stock container. Fig. 13 shows a pump connection which is suitable for the bottom part shown in Fig. 12. The stock container is locked by part 31 in the bayonet nut 40, while the thrust cam 34 will open the shut-off valve 32 through the pump feed cam 41. The bottom part, comprising valve housing 31, shut-off valve 32, valve springs 33 and thrust cam 34, is preferably made entirely of plastic.

Claims: Device for the conveyance of pasty material, comprising at least one stock container for the pasty material, in addition to at least one pump provided with a pump feed and pump discharge, and distribution means for the pasty material, in particular suitable for the printing of materials, characterized in that the stock container (3) is provided with an outflow aperture (5) which can be connected directly to the pump feed, and which in the operating position for the removal of pasty material from the stock container (3) forms essentially the lowest level of the stock container. Device according to Claim 1, characterized in that the outflow aperture (5) of the stock container (3) is provided near the bottom (6) of the container. Device according to Claim 1 or 2, characterized in that the bottom (6) of the stock container (3) is provided with a recess near the outflow aperture (5) of the container (3). Device according to Claims 1 - 3, characterized in that the bottom (6) of the stock container (3) runs sloping in the direction of the outflow aperture (5). Device according to Claim 1, characterized in that the outflow aperture (5) of the stock container (3) is disposed in a removable, preferably sloping cover (8) of the stock container (3) which is provided with an air suction aperture (10). Device according to Claims 1 - 5, characterized in that the device is also provided with tilting means (7, 22, 23) for tilting the stock container (3). Device according to Claims 1 - 6, characterized in that the pump (1) is also provided with coupling elements (13) to connect the pump feed to a container with cleansing fluid (19). Device according to Claim 7, characterized in that the coupling elements (13) are also provided with a shut-off element which may or may not be controlled automatically, preferably a three-way valve (17) which can be connected to a feed (16) of pasty material or a feed (14) of cleansing fluid, on the one hand, and to the pump feed, on the other. Device according to Claims 1 - 8, characterized in that the coupling elements (13) are detachably connected to a preferably sloping cover (8) of the stock container (3) provided with an outflow aperture (5), said outflow aperture being connected directly to the pump feed. Device according to Claim 1, characterized in that the outflow aperture (5) of the stock container (3) is disposed in a removable bottom part (30) of the stock container (3), said part being provided with coupling elements (31, 35) for connecting the pump feed to the stock container (3). Device according to Claim 10, characterized in that the removable bottom part (30) is provided with a shut-off element, which may or may not be controlled automatically, in particular a shut-off valve (32). Device according to Claim 10 or 11, characterized in that the bottom part is provided with locking means (40, 31) which can mate with means (41) for opening the shut-off element, said means being detachably connected to a pump feed.

Inventors: TOONEN, CORNELIS ANTHONIUS, VAN MONDFRANS, GERARDUS HENDRIKUS
Applicants: STORK BRABANT B.V.
Application year: 1989
Main classification: B41F31
IPC codes: B41F35, B41F31