Device for grinding and feeding of solid particles of dry ice for devices for mixing solid particles of dry ice with flow of gaseous medium Technical Field

[0001] The invention relates to devices for grinding a feeding of solid particles of dry ice, CO2 in solid state, granulate, for devices for mixing of solid particles of dry ice with the flow of gaseous medium.

Background Art

[0002] Document DE 102009027974 A1 describes a grinder, which comprises rotative rollers statically positioned against each other, wherein between them an element comprising convex milling surfaces on its sides adjacent to the rollers is placed. Grinding element is movable relative to rollers and by its shifting the distance of its milling surfaces from the rotative rollers is adjusted, thereby adjusting the size of a milling gap.

[0003] Document DE 102006000510 describes a device, which allows changing from milling mode to a mode with opened gap for granulate, without milling. This mode change is carried out by movable partition wall placed over the milling roller.

[0004] In fact, known devices comprise at least one driven rotatively mounted feeding/milling roller, whose rotation allows feeding and milling of dry ice granulate from a container to a mixing device. In these devices, granulate is fed/milled by rotation of the roller against a surface, or an inner wall of the milling device.

[0005] Disadvantage of the mentioned method of milling, i.e. milling between the roller and a surface, or a wall of the device, is low efficiency, rotation of particles of granulate before the milling gap, and also possible problems when a partition wall, or an element with milling surfaces is shifting under the load of mass of granulate stored in the container.

[0006] Aim of this invention is to eliminate disadvantages of known devices for grinding and feeding of solid particles of dry ice for devices for mixing solid particles of dry ice with the flow of gaseous medium.

Disclosure of Invention [0007] Mentioned aim is achieved by the device for grinding and feeding of solid particles of dry ice according to this invention comprising rotative roller, characterized in that, against the rotative roller, a rotative roller

eccentrically positioned on rotatively arranged supporting body is placed and provided with means for kinetic coupling with a power source.

[0008] It is advantageous when convex, cylindrical or sloping surface is provided on the rotatively arranged supporting body, adjacent to the eccentrically positioned rotative roller.

[0009] Proposed solution allows continuous and fast changing of device working mode - milling, or free passage of granulate. Milling is then realized by a pair of rotating rollers, what provides for effective way of milling - effective intake of granulate and elimination of rotation of particles of granulate before the milling gap. Convex, cylindrical, or sloping surface provided adjacent to the eccentrically positioned rotative roller favors easy passage of granulate from the container and between rollers.

[0010] Together with the milling of granulate between the two rotative rollers, the effect of feeding of granulate to a mixing device occurs.

Brief Description of Drawings

[0011] Technical solution is explained more in detail on attached drawings,

where:

[0012] Fig. 1 shows perspective bottom view of device rollers according to this invention in the position when milling granulate;

[0013] Fig. 2 shows top view of device rollers from Fig. 1 without one end plate of the rotatively arranged supporting body;

[0014] Fig. 3 shows sectional view of device according to the invention, with

rollers in the position when milling granulate;

[0015] Fig. 4 shows sectional view of device according to this invention, with

rollers in the position when granulate is passing freely;

[0016] Fig. 5 shows a view of means for kinetic coupling of the eccentrically

positioned rotative roller with driven roller during the milling of granulate;

[0017] Fig. 6 shows means for kinetic coupling of the eccentrically positioned rotative roller with driven roller during free passage of granulate.

Mode(s) for Carrying Out the Invention [0018] Device for grinding and feeding of solid particles of dry ice according to this technical solution, according to figures 1 to 6, comprises rotative roller 1_, against which, a rotative roller 3 eccentrically positioned on rotatively arranged supporting body 2 is placed and provided with means 4 for kinetic coupling with the power source 7, in this example electric motor.

[0019] The eccentric placement of the rotative roller 3 means its eccentric

position in relation to axis of rotation of rotatively arranged supporting body 2.

[0020] In this example, the surface 2JM created on the rotatively arranged

supporting body 2, adjacent to the eccentrically positioned rotative roller 3 is cylindrical. This surface 211 is created on the rotatively arranged supporting body 2 such that, during the milling of granulate it appears on the side of granulate being led to the rollers 1_, 3, thereby favoring the access of granulate to a gap between the rollers 1_ and 3.

[0021] The device as shown in Fig 3 and 4 comprises a housing 5 of the milling and feeding part, in which chambers for housing the rotative roller 1_ and for housing the rotatively arranged supporting body 2 with eccentrically positioned rotative roller 3, are provided.

[0022] On one side, as can be seen in Fig. 5 and 6, the housing 5 of the milling and feeding part is provided by a housing cap 6 of the housing 5 of the milling and feeding part. The housing cap 6 is provided by shaft supports of rotative roller 1_, of rotatively arranged supporting body 2 and of power source 7.

[0023] On the other side, the housing 5 of the milling and feeding part comprises shaft supports of rotative roller 1_, of rotatively arranged supporting body 2, and also means for coupling the shifter 9 of position of the rotatively arranged supporting body 2, so called "positioner". This position shifter 9 can advantageously be pneumatic.

[0024] The housing 5 of the milling and feeding part is, in this example, also

provided by a flange P2 for its coupling to a mixing device (not shown) and a flange PI for coupling a container of granulate (not shown).

[0025] Next follows detailed description of the embodiment of rotatively arranged supporting body 2, mounting of rotative rollers 1_, 3, and mounting of rotatively arranged supporting body 2, and also the embodiment of means

4 for kinetic coupling of the rotative rollers 1_ and 3.

[0026] Rotative supporting body 2 comprises end plates 22, 23, wherein between them the eccentrically positioned rotative roller 3 is mounted and

cylindrical surface 211 is arranged, which in this case forms integral part of cylindrical body 2j with longitudinal planar surface placed between end plates 22, 23. At least one of the end plates 22, 23 is removable. The eccentrically positioned rotative roller 3 is then placed in a cavity formed in longitudinally planar surface on the cylindrical body 2 The longitudinal planar surface 212 of the cylidrical body 2j is then made such that, it is not projecting over the outer circumference of the eccentrically positioned rotative roller 3, or at utmost is aligned with the outer circumference of the eccentrically positioned rotative roller 3.

[0027] End plates 22, 23 comprise support of the shaft 3j of the eccentrically

positioned rotative roller 3, substantially on their circumferential (edge) part, and at least one of the end plates 22, 23 can also comprise stopping element 24 corresponding with arcuate stopping groove 8 in the housing cap 6. The arcuate stopping groove 8 can also be provided in the housing

5 of the milling and feeding part.

[0028] Means 4 for kinetic coupling of the eccentrically positioned rotative roller 3 comprise gears in this embodiment, namely gear 72 of the power source 7, gear Ϊ2 of the rotative roller 1_ and gear 32 of the eccentrically

positioned rotative roller 3. Gears are mounted on shafts of corresponding parts, i.e. the shaft 71_ of the power source 7, the shaft Y_ of the rotative roller 1_, and the shaft 31_ of the eccentrically positioned rotative roller 3.

[0029] Device for grinding and feeding of solid particles of dry ice according to this invention is working as will be described further with reference to Fig. 3 and 4. In figures 3 and 4, the arrow A represents the inlet/passage of unground granulate, the arrow B the outlet of ground granulate and arrows R the direction of rotation of rotative rollers and 3.

[0030] Rotative roller is working usually always all the time of device operation.

Rotative roller \_ is through its gear λΐ driven by the power source 7 through the gear 72 of the power source 7. [0031] During the mode, when milling of granulate is not required, the rotative supporting body 2 is in the position where the eccentrically positioned rotative roller 3 is aside of the passage channel K of granulate and above the longitudinal planar surface 212 of the cylindrical body 21 The gear 32 of the eccentrically positioned rotative roller 3 is in one end position, determined by the position of the shaft 3 at the one end of the arcuate stopping groove 8. The gear 32 of the eccentrically positioned rotative roller 3 is not engaged with the gear 12 of the rotative roller 1_, and thus the eccentrically positioned rotative roller 3 is not driven, and accidentally revolves only due to a movement of granulate passing through the passage channel K of granulate. The rotative roller prevents by its rotation clogging of granulate in the passage channel K of granulate defined in this case by cylindrical surface of the rotative roller 1_, by longitudinal planar surface 212 of the cylindrical body 7 and partially also by cylindrical surface of the eccentrically positioned rotative roller 3. In this mode, the eccentric rotative roller 3 favors passage and feeding of granulate to a mixing device.

[0032] When grinding of granulate is required, the rotative supporting body 2 is rotated by the position shifter 9 to the other end position, determined by the position of the stopping element 24 at the other end of the arcuate stopping groove 8. The passage channel K is thus partially closed, wherein the milling gap is created by a pair of revolving rollers, i.e. by the rotative roller 1_ and the eccentrically positioned rotative roller 3.

[0033] The eccentrically positioned rotative roller 3, which was idle, is now by changing the position of the rotative supporting body 2 engaged along arcuate path, through the gear 32 with the gear 12 of the rotative roller 1_, and thus the eccentrically positioned rotative roller 3 begins to use for its rotation the same power source 7 as the rotative roller 1_.

[0034] The eccentrically positioned rotative roller 3 is thus engaged in the milling mode only. When not in the milling mode, the roller 3 is disengaged and is not revolving, or is revolving only accidentally due to a movement of granulate passing through the passage channel K of granulate. The device shown in figures and described in examples of embodiments represents the best construction embodiments. This particular

embodiment is introduced only as an illustrative example for disclosure of the technical solution. It is obvious that also other construction variants are possible within the idea of this technical solution, e.g. regarding

constructional embodiment of the means 4 for kinetic coupling and their arrangement, embodiment of the power source 7, mounting of the rotative supporting body 2, as well as the embodiment of substantially sloping surface 2V adjacent to the eccentrically positioned rotative roller 3, or embodiment of the cylindrical body 21 with longitudinal planar surface, as well as arrangement and embodiment of the position shifter 9, etc.