Dry ice container for dry ice cleaning devices

Technical Field

[0001] The technical solution relates to dry ice container for dry ice cleaning

devices, particularly for so-called two-hose devices for dry ice blasting. Dry ice means solid CO2, and the two-hose device means a device which comprises a pair of lines which enters the mixing node, which is realized by Venturi tube integrated in the body of the blast gun, while one line supplies compressed air and the second line supplies dry ice pellets using negative pressure.

Background Art

[0002] There are known dry ice containers for dry ice cleaning devices comprising a container, in which dry ice is drawn out by negative pressure to the blast gun. In said containers, air is drawn through the entire volume of the container, so is through the entire volume of dry ice present in the container, what results in degradation of dry ice pellets by humidity contained in atmospheric air. The pellets tend to form lumps, which hinder correct function of the entire cleaning device. This drawback is solved such that a device is provided for crushing of dry ice, or for reducing the size of the pellets, placed at the bottom of the container, so the pellets could pass through the openings at the bottom of the container to the outlet port and to be drawn out by negative pressure to the blast gun. Container of this type is disclosed in e.g. EP 2832499 A1.

[0003] Problem of providing substantially homogenous, or continuous flow of drawn out dry ice pellets is also being solved in EP 1 769 886 A1. The device comprises a container for dry ice, into which a hose for drawing out the pellets is inserted at its bottom, whereas this hose can make reciprocal motion and against this hose, a pipe for supplying atmospheric air discharges in sloped bottom part of the container. The pipe for supplying atmospheric air supports drawing out the pellets and its discharge in the bottom part of the container before the suction hose of the pellets ensures that the entire volume of pellets present in the container is not exposed to the flow of air. Motion of the hose for sucking out the pellets then provides for the movement of pellets near the hose suction tip, thus preventing choking of the suction channel. The hose for sucking out the pellets moves in the direction of the axis of the container and against stop-end plate at discharge of the pipe for supplying the pressurized air. Such arrangement allows to reduce size of the pellets. Described solution is in certain scope able to provide problem free transport of the pellets to the blast gun.

However, this device is characterized by relatively complex construction and relatively small section for the flow of pellets, what can, despite the measures proposed in this solution, lead to the blocking of the flow of pellets. Further, due to the fact that atmospheric air is supplied to the pellets, the chance of generation of lumps or clusters is still present, even despite the short distance of travel of air through the pellets.

[0004] The object of this solution is to provide a container, which would be

characterized in simpler construction and efficient operation, while generation of clusters of pellets would be reduced to minimum, or even fully prevented.

Disclosure of Invention

[0005] Said object is attained by dry ice container for dry ice cleaning devices according to this invention, which comprises a container (1) for dry ice closed by a lid (2) on the upper side, and provided by an opening (3) for drawing out dry ice pellets on the lower side, where the container (1) has the bottom (4) sloped towards the opening (3) for drawing out the pellets, at which linear-movable member (5) is arranged, and supply of auxiliary air is discharged above the bottom (4) of the container (1), characterized in that the linear-movable member (5) is arranged in a chamber (6) at the bottom (4) of the container (1) transversely to the axis of the container (1), where the member (5) has the shape of a gutter in which groups of separated openings (5a, 5b, 5c) are provided, to which at least one pellets plowing element (5d) is placed in the member, each group of openings (5a, 5b, 5c) pertains to one opening (3) for drawing out the pellets, where the openings (3) for drawing out the pellets are connected through a collector (7) to an outlet (8) of the pellets, the member (5) is connected to the piston of pneumatic cylinder (10), and the supply of auxiliary air above the bottom (4) of the container (1) is formed by a tubular body (1 1) transversely extending through the container (1) in the direction of the member (5), where the body (1 1 ) is outside the container (1 ) at one end connected to a source of auxiliary air, inside the container (1 ) it is provided at least by one opening (12) of the outlet of auxiliary air arranged against the bottom (4) of the container (1 ), and on the other end outside the container (1 ) it is provided by an opening (13) for the outlet of residual auxiliary air.

[0006] It is preferred, if the source of auxiliary air is the outlet of dump operating air from the pneumatic cylinder (10).

Brief Description of Drawings

[0007] This invention is better explained on accompanying drawings, where

[0008] Fig. 1 shows overall outside view of the container according to this

invention with schematic connection of the blast gun;

[0009] Fig. 2 shows the view of the lower part of the container of fig. 1 in partial section;

[0010] Fig. 3 shows overall view of the linear-movable member; and

[001 1 ] Fig. 4 shows the lower part of the container according to this invention in side sectional view.

[0012] Arrows or arrows with associated lines shown in drawings represent

respective directions and flows of the air, or air with pellets in the entire device and the container.

Mode(s) for Carrying Out the Invention

[0013] The device comprising the container 1_ according to this invention is

schematically shown in Fig. 1. The device is composed of pair of lines leading to the mixing node, which is realized by Venturi tube integrated in the body of blast gun 5. The first line A (positive pressure) represents the inlet system of gaseous medium. The second line B (negative pressure) serves for transport of the pellets to the mixing chamber in the blast gun 1J5.

[0014] Dry ice container for dry ice cleaning devices according to this invention, according to Figs. 2 to 4 comprises the container 1_ for dry ice closed by the lid 2 on the upper side, and provided by the opening 3 for drawing out dry ice pellets on the lower side. The container 1_ has the bottom 4 sloped towards the opening 3 for drawing out the pellets. Linear-movable member 5 is arranged transversely to the axis of the container 1_, in the chamber 6 at the bottom 4 of the container 1_. The member 5 is in the form of a gutter, in which groups of separated openings 5a, 5b, 5c are provided. To each group of the openings 5a, 5b, 5c, the pellets plowing element (5d) is placed in the member 5. Each group of openings 5a, 5b, 5c pertains to one opening 3 for drawing out the pellets, the number of which is in this example two. The openings 3 for drawing out the pellets are connected through the collector 7 to the outlet 8 of the pellets. The member 5 is connected to the piston of pneumatic cylinder 10. The supply of auxiliary air at the bottom 4 of the container 1_ is formed by tubular body 12 transversely extending through the container in the direction of the member 5. The body 12 is outside the container 1_ at one end connected to the source of auxiliary air. The body VI is inside the container 1_ provided by at least one opening 3 of the outlet of auxiliary air, which is arranged against the bottom 4 of the container 1_. The body 12 is on the other end outside the container 1_ provided by the opening 14 for outlet of residual auxiliary air.

Pellets are inserted into the container 1_. The pellets are supplied to opened chamber 6 by the gravity and sloping of the bottom 4 of the container 1_. Movable gutter, i.e. the member 5 performs linear

reciprocation motion through the pellets, while pellets plowing element 5d creates above the openings 3 for drawing out the pellets, which are continuously consecutively opened by the openings 5a, 5b, 5c and closed by solid areas between these openings 5a, 5b, 5c, the air gaps that are subsequently filled with incoming pellets. The pellets are passing to suction openings 3 through the member 5 by the openings 5a, 5b, 5c during their transition over the suction openings 3. In this example of embodiment, the number of the openings 5a, 5b, 5c is three. The outer openings 5a, 5c provide for the flow of the pellets to the opening 3 at the end positions of the member 5 and the middle opening 5b provides for the flow of the pellets also during the motion of the member 5 (not only at the end positions), thus ensuring continuity of the flow of the pellets to respective opening 3. The number, shape and spacing of the openings 5a, 5b, 5c, can be adjusted according to the needs, and so can be the number and shape of the plowing elements 5d. In this example of embodiment, the plowing elements 5d are in the form of walls, each of them pertaining to one group of openings 5a, 5b, 5c. Moving member 5 is plowing the pellets, i.e. preventing formation of clusters of pellets, in front of the openings 3, while by continuous consecutive opening and closing of the openings 3 for drawing out the pellets, is preventing their blockage by the pellets drawn in from above and regulates amount of passing pellets.

[0016] The flow of pellets is supported by supply of the auxiliary air to the pellets in the lower part of the container 1_, i.e. in the area of the bottom 4, where the pellets shortly after enter the opened chamber 6. Preferably, working air dumped from the pneumatic cylinder ^O that serves to drive the member 5, is supplied to the tubular body 12. Part of the volume of passing air supplies feeding system of the device through the opening 13 of the outlet of auxiliary air, the most preferably in the shape of longitudinal groove, aperture. This system supplies the container 1_ with sufficient volume of treated air, the system takes from this source adequate amount and the redundant part is dumped through the opening 14 for the outlet of residual auxiliary air. As was mentioned above, the pneumatic system, i.e. pneumatic cylinder 1C) is preferably used as the source of auxiliary air, because this air is passing through purification and humidity separation before its use, thus its adverse effect on quality of the pellets decreases.

[0017] Above described example of embodiment represents only one particular construction embodiment of the container according to this invention, while this example is introduced only as an illustrative example to explain the principle of the technical solution and it is not in any way limiting also for other constructional variants within the scope of the claims.