Shredding device and a method using such a shredding device

Abstract

The invention relates to a shredding device (1) used for picking apart compressed blocks (2) of loose-fill cellulose thermal insulation material. It comprises a chute (3) with a chute inlet (3a) configured to receive the insulation block (2). Further, it comprises a shredder (4) rotatable around a substantially horizontal axis (A), mounted at an outlet (3b) of the chute (3). The device (1) is characterized in that the rotatable shredder (4) is a cylinder with protruding grating pins (5) arranged on its mantel surface (4), where the pins (5) have a length shorter than the radius of the cylinder and are adapted to grate, pick apart and fluff the insulation from the compressed block format (2) into a fluff material with an even density. Further, the invention relates to a method for picking apart loose-fill cellulose thermal insulation material compressed into a block (2).

Claims

1. A cellulose thermal insulation shredding device adapted to be mounted on a loose-fill insulation apparatus and to pick apart compressed blocks of loose-fill cellulose thermal insulation material comprising a transportation device for blocks of insulation material and a shredder rotatable around a horizontal axis and being mounted in the vicinity of the transportation device, wherein the compressed blocks of loose-fill cellulose thermal insulation material is transported towards the shredder during operation, wherein the rotatable shredder is a cylinder having a mantel surface, wherein protruding pins are arranged on the mantel surface, wherein the pins have a length shorter than the diameter of the cylinder, wherein the pins are arranged in a continuous pattern distributed across the cylinder mantel surface, and wherein the pins, during rotation of the rotatable shredder, grate, pick apart and fluff the insulation from the compressed block format into a fluff material with a density less than the density of the compressed material.

2. A shredding device according to claim 1, comprising a single rotatable cylinder.

3. A shredding device according to claim 1, wherein the pins have a length of between 0.5 and 100 mm.

4. A shredding device according to claim 1, wherein the pins are distributed with a mutual distance of between 5 and 150 mm.

5. A shredding device according to claim 1, comprising a sealing mounted in the chute opening and adapted to enclose a compressed block and to prevent dust from exiting the opening.

6. A loose fill insulation apparatus comprising a shredding device according to claim 1, wherein the loose fill insulation apparatus is a single unit, with the transportation device and the rotatable cylinder mounted on a frame mounted on the loose fill insulation apparatus.

7. A loose fill insulation apparatus according to claim 6, comprising a power transmitting element adapted to rotate the rotatable cylinder.

8. A shredding device according to claim 1, wherein the transportation device comprises a chute.

9. A shredding device according to claim 8, wherein the chute comprises a chute opening configured to receive the block of insulation material.

10. A shredding device according to claim 9, wherein the chute opening has a closure part to prevent dust from exiting the opening.

11. A shredding device according to claim 10, wherein the closure part is a pivotable wall section.

12. A method for picking apart a block made by loose-fill cellulose thermal insulation material and compressed to a density of at least 160 kg/m.sup.3 by using the steps: positioning the insulation block on the transportation device of a shredding device according to claim 1; feeding the insulation block into the shredding device; and milling the insulation block by rotation of the cylinder in the shredder device so that a fluffed loose-fill insulation material is formed, having a substantially even density of less than 35 kg/m.sup.3 which is ready to be distributed.

13. A method according to claim 12, wherein the shredding device comprises a chute with a chute inlet, the method comprising a step sealing the chute opening from dust by closing a closure part after the insulation block has been fed into the chute.

14. A method according to claim 13, wherein the chute opening is automatically opened when the insulation block touches a closure part and is automatically closed after the insulation block has passed the closure part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 discloses a first embodiment of the shredder device mounted on a loose-fill insulation apparatus,

(2) FIG. 2 discloses a second embodiment of the shredder device mounted on a loose-fill insulation apparatus,

(3) FIG. 3a discloses a first embodiment of the shredder cylinder, and

(4) FIG. 3b discloses a second embodiment of the shredder cylinder.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

(5) The invention will now be described in more detail in respect of embodiments and in reference to the accompanying drawings. All examples herein should be seen as part of the general description and therefore possible to combine in any way in general terms. Again, individual features of the various embodiments may be combined or exchanged unless such combination or exchange is clearly contradictory to the overall function of the device.

(6) FIG. 1 discloses a shredding device 1 for picking apart compressed blocks 2 of loose-fill of cellulose thermal insulation material according to the invention. The shredding device 1 comprises a chute 3 with a chute inlet 3a in which the insulation block 2 is inserted. The chute has a substantially rectangular cross section and is adapted to receive the insulation block. The measures of the height and width of the rectangular cross section can be substantially different from each other, for example may the height of the chute be approximately 60% of the width. Other measures are of course possible. Further, the length of the chute 3 is preferably longer than a 600 mm, i.e. longer than the arm of a normal person.

(7) In the vicinity of a chute outlet 3b a shredder cylinder 4 is mounted. The chute outlet 3b is preferably leading into a volume 8 in which the fluffed loose-fill insulation is to be stored before it is injected into structures. The shredder cylinder 4 is rotatable around a substantially horizontal axis A and has several protruding grating or milling pins 5 arranged on its mantel surface 4. Preferably the diameter d of the shredder cylinder 4 is between 110 and 500 mm, preferably between 150 and 400 mm or approximately between 60 and 90% of the height of the chute 3. The pins 5 are adapted to grate, pick apart and fluff the insulation into a required density of preferably less than 35 kg/m.sup.3. Only one single rotatable shredder cylinder 4 is needed to pick apart the compressed insulation into the preferred density. The less dense material has an even density which easily can be injected into the structure to be insulated without the risk of jamming the machine or its external pipes.

(8) The loose-fill insulation apparatus 7 of FIGS. 1 and 2 includes a hopper 8 forming storage for the fluffed insulation and an outlet 9 to which a flexible tube 10 is mounted. Further the insulation apparatus includes a power transmitting element 11, preferably an engine rotating a drive shaft, and a compressor 12. The loose-fill insulation material has reached the hopper 8 through the shredding device 1 which has fluffed it into the required density. The required density is lower than the density of the block 2 of compressed insulation fed through the shredding device 1. Before the material is blown into the structure to be insulated, the material also passes a feeder 15 and a rotatable air lock 16, in the apparatus 7. The compressor 12 creates airflow through the air lock 16, with a pressure enough to blow the loose-fill insulation into the structure.

(9) The rotation of the shredding cylinder is in FIG. 1 performed by the power transmitting element or engine 11 associated with the insulation apparatus.

(10) Preferably, the engine is rotating at a speed of between 1400 and 1800 revs/min. The engine 11 is connected to a central axis of the shredding cylinder, rotating it at the required speed. In the embodiment according to FIG. 2 the shredding device includes a separate power transmitting element 13 attached to the single separate unit. The power transmitting element 13 is connected to and adapter to rotate the shredder cylinder 4. The power transmitting element 11, 13 can for example be driven by electricity, hydraulics or air pressure.

(11) In FIG. 2 the chute inlet 3a is covered by a closure part 6 adapted to prevent dust from exiting the opening. The closure part 6 is a wall pivotable around its upper edge 6a and in its normal position it is closed and seals the chute inlet 3a. It is in an open position only when an insulation block 2 is passing the closure part 6 on its way towards the shredder cylinder 4. Thus, the chute inlet 3a is opened when the block 2 touches the closure part 6 and presses into an open position and closed after the block 2 has passed the closure part 6. He closure part may also be opened automatically by an external opening actuator operated by the operator of the device.

(12) When the insulation block 2 is passing the closure part 6 and the closure part is opened, some dust may pass the block 2 and exit from the inlet 3a. Therefore a second sealing 17 can be placed in the chute 3, preferably between the closure part 6 and the chute outlet 3b. This second sealing 17 encloses the block 2 as long as the closure part 6 is opened. Preferably the second sealing 17 is a brush strip or some other sealing strips providing an appropriate sealing effect with a low friction against the block. The second sealing 17 can also be used as the only dust preventing arrangement. Thus the sealing 17 may be used without the closure part 6. The sealing 17 is then placed somewhere between the chute inlet 3a and outlet 3b, but preferably closer to the inlet 3a than the outlet 3b.

(13) In FIG. 2 the shredding device 1 is constructed as a single separate unit adapted to be mounted on a loose-fill insulation apparatus 7. The chute 3 and the rotatable shredder cylinder 4 are mounted on a frame 14, which is specially adapted to fit different types of insulation apparatuses.

(14) The distance h between the top of the grating pins 5 on the cylinder 4 and the part of the chute 3 on which the blocks 2 of compressed insulation material are transported, is adjustable. Preferably the distance is adjustable between 0 and 30 mm.

(15) The chute 3 can be mounted at an angle relative to the ground so that the insulation block 2 is transported towards the cylinder by gravity force alone. However, the block 2 can also be automatically transported on a transporting device, for example an endless band, to the shredder cylinder 4. If the block is automatically transported into the shredder cylinder 4, the chute 3 can have any angle relative the ground. This facilitates for the operator of the device, since the insulation blocks do not have to be lifted so far from the ground level.

(16) In a first embodiment of the shredder cylinder, show in FIG. 3a, the grating pins 5 are separate pointed parts with a length L attached to the mantel surface 4 of the shredder cylinder. They can be attached with separate fastening devices such as for example screws and rivets or they can be welded or glued to the surface 4.

(17) The mantel surface 4 of the shredder cylinder can also be covered by a layer of rubber or a rubberlike like material. The rubber layer can for example be vulcanized on the surface 4. A rubber surface increases the friction between the block 2 and the cylinder 4 and further improves the grating process. Further, the grating pins 5 can easily be attached to such a surface and it is also easy to replace lost or broken pins 5.

(18) The length L of the pins 5 is shorter than the diameter d of the shredder cylinder 4 on which the pins are attached or integrated with. Preferably the ratio between pin length and cylinder diameter L/d is between 0.001 and 0.9, or between 0.01 and 0.5, or between 0.05 and 0.15. When the length of the pins 5 is short relative to the cylinder diameter, the insulation material is milled rather than beaten into a less dens material.

(19) The grating pins 5 can in a second embodiment be made from the same part as the shredding cylinder 4. For example can the shredder cylinder 4 consist of a base cylinder 4a, which can be either hollow or solid, around which a sheet of metal 4b is wrapped creating the cylinder mantel surface 4.

(20) In FIG. 3b, this embodiment of the shredder cylinder, the pins and the making there of is disclosed. In the metal sheet 4b v-shaped patterns 5 are punched in a substantially continuous pattern spread over the whole sheet with a distance of 5 mm to 150 mm from each otherpreferably a horizontal distance varying between 5 and 100 mm, more preferably between 5 and 20 mm, and a vertical distance of approximately 5 to 150 mm, more preferably between 20 and 100 or a minimum vertical distance of 20 mm. The grating pins are created by folding each v-shaped pattern around its top edge so that a triangular pin is formed, preferably, with a top to bottom length L of between 0.5 and 100 mm. The number of pins 5 is preferably approximately one pin per cm.sup.2.