Abstract
The invention relates to a device for dispensing dry ice snow, comprising a storage container (10) for receiving dry ice snow and vibrating means (102) and/or scraping means (103). An insert plate (105) with through-openings (106) is provided. The insert plate is located in the interior of the storage container (10), divides the storage container (10) into two regions, and can be set vibrating by means of the vibrating means (102) and/or scraped by means of the scraping means (103).
Claims
1. A device for dispensing dry ice snow as a material to be conveyed, the device comprising: a storage container for receiving dry ice, a compressed aft gun for dispensing dry ice, a conveying line connecting the storage container to the compressed air gun, and a vibrating means, wherein an insert plate with through-openings is located inside the storage container, the insert plate is arranged within and divides the storage container into two regions such that the dry ice snow lies on a flat surface of the insert plate and can fall through the through-openings of the insert plate, and wherein the insert plate can be vibrated by the vibrating means, the insert plate supports an impact member which engages with a movable impact device of the vibrating means, the vibrating means is a pneumatic cylinder, and the impact device also forms an intake fitting for the conveying line which connects the storage container with the compressed air gun for supplying the dry ice snow.
2. The device as claimed in claim 1, wherein the device comprises an extraction device (115) by which sublimated CO.sub.2 gas and particles can be extracted.
3. The device as claimed in claim 1, wherein the insert plate comprises the impact member formed on a bottom surface thereof.
Description
(1) The invention will be explained in greater detail hereinafter in exemplary embodiments on the basis of the drawings, in which:
(2) FIG. 1 shows a schematic illustration of a device for cleaning using dry ice pellets from the prior art;
(3) FIG. 2 shows a schematic illustration of the storage container of a device according to the invention for cleaning using dry ice pellets;
(4) FIG. 3a shows a schematic illustration of a storage container of a device according to the invention with an insert plate with through-openings;
(5) FIG. 3b shows a schematic illustration of a storage container of a device according to the invention with a second variant for an insert plate;
(6) FIG. 3c shows a schematic illustration of a storage container of a device according to the invention with a third variant for an insert plate;
(7) FIG. 4 shows a schematic illustration of the storage container of a device according to the invention for cleaning using dry ice pellets with an inner container;
(8) FIG. 5 shows a schematic illustration of a storage container of a device according to the invention with an insert plate with through-openings in an inner container;
(9) FIG. 6 shows a schematic illustration of a storage container of a device according to the invention with an insert plate with through-openings provided with a bearing ring;
(10) FIG. 7 shows a schematic illustration of a storage container of a device according to the invention with an insert plate with through-openings and a vibrating means acting from above;
(11) FIG. 8 shows a schematic illustration of a storage container of a device according to the invention with an insert plate with through-openings and a vibrating means acting from above;
(12) FIG. 9 shows a schematic illustration of a storage container of a device according to the invention for cleaning using dry ice with an inner container that can be vibrated, wherein the vibrating means acts from above;
(13) FIG. 10 shows a schematic illustration of a storage container of the device according to the invention with a scraping means;
(14) FIG. 11 shows a schematic illustration of different variants of through-openings;
(15) FIG. 12 shows a schematic illustration of a device according to the invention for cleaning using dry ice snow with an extraction device with two arrangement variants a) and b);
(16) FIG. 13a shows a schematic illustration of a storage container of a further device according to the invention for cleaning using dry ice pellets and dry ice snow;
(17) FIG. 13b shows a schematic illustration of a storage container of a further device according to the invention for cleaning using dry ice snow;
(18) FIG. 14a shows a schematic illustration of a storage container of a further device according to the invention for cleaning using dry ice pellets and blasting means;
(19) FIG. 14b shows a schematic illustration of a storage container of a further device according to the invention for cleaning using dry ice snow and blasting means.
(20) The structure of a device 1 according to the invention for cleaning using dry ice is illustrated schematically in FIG. 1 and is also known from the prior art, for example from EP 1 769 88. The device 1 comprises a compressed air device 101, a storage container 10 for receiving dry ice T and a pneumatic cylinder 14 driven by the compressed air device 101. The dry ice T is located in the storage container 10 and is guided into a compressed air gun 31 by means of the compressed air device 101, said compressed air gun generating a negative pressure at an intake fitting 11. The dry ice T thus reaches an area to be cleaned at high speed (blasting).
(21) FIGS. 2 to 10 each show a detail of a device as shown in FIG. 1, but modified in accordance with the invention, in each case showing a storage container 10 provided with a vibrating means 102, scraping means 103 or a selecting element in a respective variant for conveying dry ice.
(22) FIG. 2 shows the storage container 10 and, as a selecting element 104 for conveying pellets, a mixing element 15 with an air feed pipe 16, through which air is sucked up and in which ambient moisture can condense. Less ambient moisture therefore precipitates inside the container 10 and on the dry ice. The vibrating means 102 in this case comprises the pneumatic cylinder 14 connected to an intake fitting 11 that moves up and down along the longitudinal direction L. At the end of the upward movement, the intake fitting 11 contacts a contact face 13. Dry ice pellets located between the intake fitting 11 and the contact face 13 are comminuted due to the movement to and fro of the intake fitting 11 and are extracted through the intake fitting 11. A mandrel 118 ensures that no pellets become wedged in the intake fitting 11 and keeps free the outlet opening.
(23) In the variant illustrated in FIG. 3a, an insert plate 105a with through-openings 106 is located as a selecting element 124 in the storage container 10. The insert plate 105a is provided with an impact member 107. The vibrating means 102 in this case comprises the pneumatic cylinder 14 connected to the intake fitting 11 that moves up and down along the longitudinal direction L. The insert plate 105a is vibrated as a result of the contact of the intake fitting 11 against the impact member 107. Dry ice snow located on the plate 105a is thus sieved through the through-openings 106 (not shown explicitly in the figure) and is extracted through the intake fitting 11. The impact member 107 may have an additional mandrel (not illustrated in the figure).
(24) In the variant illustrated in FIG. 3b, an insert plate 105b with an impact member 107b, which additionally has a mandrel 118 reaching into the intake fitting 11, is located as a selecting element 124b in the storage container 10. The mandrel 118 is used to guide the to-and-fro movement, since the insert plate 105b has a smaller diameter than the inner opening of the storage container 10 in the cylindrical region. In the rest position, the insert plate 105b sits in the conical region of the storage container 10 and thus divides the container into two regions.
(25) In the variant illustrated in FIG. 3c, an insert plate 105c, which has a greater thickness and therefore is solid and impact resistant, is located as a selecting element 124c in the storage container 10. An impact member is not necessary. The mandrel 118 reaching into the intake fitting 11 is fastened directly to the insert plate 105c. The insert plate 105c may have through-openings. In the present example, the diameter of the insert plate 105c is smaller than the inner diameter of the storage container 10 in the cylindrical region. The insert plate 105c has no through-openings, since the dry ice snow can slide past the insert plate 105c and into the intake fitting 11.
(26) FIG. 4 shows a storage container of a device according to the invention, wherein a mixing element 15, connected to an inner container 109, for conveying dry ice pellets is provided as a selecting element 134. If the selecting element 134 is swapped, the rest of the pellets remaining in the inner container 109 are simultaneously removed from the device.
(27) FIG. 5 shows a storage container of a device according to the invention, wherein an insert plate 105, connected to an inner container 109, for conveying dry ice snow is provided as a selecting element 144. If the selecting element 144 is swapped, the rest of the snow remaining in the inner container 109 is simultaneously removed from the device.
(28) The inner container 109 is movable relative to the container 10. In particular, it is attached such that it has play relative to the storage container 10 so that the entire inner container 109 can be vibrated.
(29) The vibrating means 102 in this case comprises the pneumatic cylinder 14 connected to the intake fitting 11 that moves up and down along the longitudinal direction L. The insert plate 105 is vibrated together with the inner container 109 due to the contact of the intake fitting 11 against the impact member 107. Dry ice snow located on the plate 105 is thus sieved through the through-openings 106 (not shown explicitly in the figure) and is extracted through the intake fitting 11.
(30) In one embodiment of the invention, the storage container 10 may receive 2 L of dry ice, corresponding to 1 kg of dry ice snow or 1.5 kg of dry ice pellets. To this end, the storage container approximately has an inner diameter of 150 mm and a height of 160 mm.
(31) To convey dry ice snow, an inner container 109 with an insert plate 105 is preferably fitted in the storage container 10. The inner container 109 comprises a cylindrical part 117 and a conical part 110, which are manufactured from polyethylene. The wall thickness of the inner container 109 is approximately 10 mm and the height of the conical part 110 is approximately 40 mm. The insert plate 105 is installed between the cylindrical part 117 and the conical part 110. The insert plate 105 is preferably a square woven mesh made of stainless steel with a mesh width of 3 mm.
(32) If the pneumatic cylinder 14 is operated at a frequency of 1-20 Hz and ensures an axial movement amplitude of the inner container 109 of approximately 1-20 mm, the dry ice snow is thus conveyed at a rate of approximately 5-10 kg/h.
(33) Instead of the inner container with an insert plate, a mixing element 15 as shown in FIG. 2 may be arranged as an alternative selecting element 104 in the storage container 10, or else a mixing element 15 attached in an inner container 109, as shown in FIG. 4. The device 1 can then be used to convey pellets.
(34) By inserting a suitable selecting element, the device can thus be used both to clean sensitive areas (selecting element formed of an inner container with insert plate for conveying dry ice snow) and to clean highly soiled or less sensitive areas (selecting element formed of a mixing element for conveying dry ice pellets).
(35) As a selecting element 154, FIG. 6 also shows a storage container 10 with an insert plate 105, which is supported by springs in this instance. The insert plate 105 is additionally provided with a bearing element, in this case a bearing ring 108. In particular, the bearing ring is not connected to the insert plate 105 and presses the upwardly moved plate 105 back downwards as a result of its gravitational effect. Since the ring is not connected to the plate, or at least is not rigidly connected to the plate, it is catapulted vertically upwardly as the plate 105 moves upwards. The fact that the ring 108 falls back onto the plate 105 ensures that said plate is again moved downward. As it falls back, the ring 108 impacts against the insert plate 105 and the jolt produced thereby allows dry ice arranged on the plate 105 to fall through the through-openings 106. At the same time, dry ice snow located between the ring 108 and plate 105 is pressed through the through-openings.
(36) The bearing element 108 is preferably a ring made of metal or plastic, with a wall thickness between 5 and 20 mm, preferably approximately 10 mm, and a height between 40 and 60 mm, preferably approximately 50 mm.
(37) The dry ice thus conveyed is extracted through the intake fitting 11.
(38) In the variant illustrated in FIG. 7, the vibrating means 102 comprises a pneumatic cylinder 14. This is connected to an impact device that is effective from above, in the present example a hammer 114, which is movable up and down along the longitudinal direction L. The selecting element 164 in the present case is an insert plate 105 with through-openings 106. The insert plate 105 is vibrated as a result of the impact of the hammer 114 against the plate 105. Dry ice located on the plate is thus sieved through the plate 105 and is extracted through an intake fitting 11. Depending on the type and size of the through-openings and depending on the vibration frequency, dry ice snow or dry ice pellets can thus be conveyed selectively.
(39) In the variant illustrated in FIG. 8, the vibrating means 102 comprises an ultrasound device 17. This is connected to an impact device that is effective from above and that moves a connecting rod up and down along the longitudinaldirection L. The selecting element 174 is an insert plate 105 with through-openings 106. The connecting rod is coupled directly to the insert plate 105, so that the insert plate 105 is vibrated in the event of movement of the rod. Dry ice snow located on the plate is thus sieved through the plate 105 and extracted through an intake fitting 11.
(40) In the variant illustrated in FIG. 9, an inner container 109 that is movable relative to the container 10 is located as a selecting element 184 inside the storage container 10. In particular, the inner container 109 is attached such that it has play relative to the storage container 10 so that the entire inner container can be vibrated. The inner container 109 comprises a cylindrical upper part 117 and a conical lower part 110, which has as at least one outlet opening 116. The vibrating means 102 comprises a pneumatic cylinder 14 and is connected to an impact device, in the present example to a hammer 114, which acts from above on the inner container 109, in particular on the conical part 110. The hammer 114 is moved up and down along the longitudinal axis L by the pneumatic cylinder 14. The inner container 109 is vibrated as a result of the impact of the hammer 114 thereon, and dry ice located in the inner container 109 is conveyed through an outlet 116 in the conical part 110. The dry ice thus conveyed is extracted through an intake fitting 11.
(41) In the variant illustrated in FIG. 10, an insert plate 105, preferably fastened in a sprung manner, with through-openings 106 is located as a selecting element 194 in the storage container. The device additionally comprises a scraping means 103, which in this case is connected to a drive 111 via a drive rod 112. The drive 111 thus drives a rasping tool 113 by means of the drive rod 112, for example in the manner of a passe-vite. The rasping tool 113 is in contact with an insert plate 105 having through-openings 106 and strips this insert plate 105. Dry ice located in the storage container 10 is conveyed through the insert plate 105 by means of the rasping tool 113 and is extracted through an intake fitting 11.
(42) Different variants of through-openings are shown in FIG. 11. Image a) shows a square woven mesh, in which the gaps between a structure arranged in a grid-like manner form net-like through-openings 106a. The square woven mesh preferably has an open sieve area of 50-70%. For example, a square woven mesh having a mesh width of 3 mm, a wire diameter of 1 mm, a mesh number of 6.4 and an open screen area of 56% can be used.
(43) In image b), square, rectangular, oval or honeycomb-shaped recesses in a plate form through-openings 106b1, 106b2, 106b3, 106b4.
(44) In image c), circular recesses in a plate form circular through-openings 106c. A perforated plate is formed by the recesses.
(45) As shown in image d) the recesses 106d can also be arranged as annular segments.
(46) The recesses can be cut out, for example using a laser or water jet, or can be punched out.
(47) FIG. 12 shows a device 1 according to the invention for cleaning using dry ice snow with an extraction device 115. In this case, the dry ice snow is blasted by means of the device 1 onto the surface, for example of a vehicle. At the same time, sublimated gas and detached dirt particles are extracted by means of the extraction device 115.
(48) In an arrangement variant a), the device 1 and extraction device 115 are arranged such that the interior of the vehicle is cleaned. The device 1 and extraction device 115 are attached to opposite windows, which allows a flow of air, dry ice, particles and gas through the interior of the vehicle.
(49) In the arrangement variant b), the device 1 and extraction device 115 are arranged such that the engine chamber of the vehicle is cleaned. The dry ice is in this case blasted into the engine chamber with the engine lid open. Air, dry ice, particles and gas are extracted from beneath the engine chamber by a means of the extraction device 115.
(50) FIG. 13a shows a detail of a device as shown in FIG. 1, but modified, and shows a storage container 10 provided with a vibrating means 102 and selecting element 224 in a variant for conveying dry ice snow and dry ice pellets.
(51) In the shown example, the selecting element 224 is a ball 205 freely movable in the storage container 110. The ball is moved by the intake fitting 11, which is movable to and fro, and rolls back in the direction of the intake fitting 11 due to the conical shape of the storage container 10.
(52) The ball 205 may loosen up pellets and provides a contact face for the intake fitting, which can be moved against the ball 205 in such a way that dry ice pellets are comminuted between the contact face and the intake end of the intake fitting 11.
(53) On the other hand, the moving ball 205 may counteract clumping of dry ice snow and may also be used to a certain degree for the portioning of dry ice snow that may travel past the ball 205 and reach the intake fitting.
(54) For example for freshly produced dry ice snow and/or freshly produced dry ice pellets, the use of the ball 205 as a selecting element 224 may be sufficient to be able to convey both pellets and snow.
(55) Dry ice snow can be conveyed particularly effectively if, as shown in FIG. 13b, the storage container 10 is equipped with a ball 205 and with an insert plate 105d having through-openings.
(56) The insert plate 105d ensures that the ball 205 remains in the vicinity of the intake fitting and loosens the dry ice snow next conveyed in. At the same time, further dry ice snow is allowed to slide down. Dry ice snow that has been reliably loosened is thus conveyed.
(57) The insert plate 105d can be connected fixedly to the storage container 10, loosely on a protrusion, as shown in the figure, or may rest on the inner face of the storage container 10 in the conical region.
(58) The cleaning effect can be further improved if a blasting agent, such as glass, sand, plastic, corundum, steel, silicon carbide or calcium carbonate, is added to the dry ice; this is true both for cleaning using dry ice pellets and for cleaning using dry ice snow. To this end, the blasting agent can be mixed with the dry ice and conveyed together therewith. The blasting agent tends to trickle through the dry ice however. A greater proportion of blasting agent is therefore conveyed initially over the course of the blasting process and then decreases later.
(59) It has therefore proven to be advantageous if the blasting agent is only added to the dry ice during the course of the blasting process.
(60) FIG. 14a shows a schematic illustration of a storage container 10 of a further device according to the invention for cleaning using dry ice pellets and blasting agent, this device being analogous to the device shown in FIG. 2.
(61) FIG. 14a shows the storage container 10 and a mixing element 15 as a selecting element 104 for conveying pellets. Air and blasting agent 120 are sucked up through the pipe 16. The blasting agent 120 reaches the storage container 10 through openings 119 in the pipe 26 and mixes above the intake fitting 11 with the pellets. The mixture is then extracted together through the intake fitting 11.
(62) FIG. 14b shows a schematic illustration of a storage container 10 of a further device according to the invention for cleaning using dry ice snow and blasting agent, this device being analogous to the device shown in FIG. 3a.
(63) In the variant illustrated in FIG. 14b, an insert plate 105a with through-openings 106 is located as a selecting element 124 in the storage container 10. The insert plate 105a is provided with a pipe 16. Air and blasting agent 120 are sucked up through the pipe 16. The blasting agent 120 reaches the storage container 10 through openings 119 in the pipe 16 and mixes above the intake fitting 11 with the dry ice snow, which slips through the openings 106 in the insert plate 105a when the intake fitting 11 moving to and fro impacts against the pipe 16 connected to the plate 105a.
(64) The mixture is then extracted together through the intake fitting 11.
