The present invention relates to a granulator mill housing for a granulator, comprising a rotor space in which a rotor fitted with knives is rotatably mounted, and a number of seats against which fixed knives may he clamped by means of screws and guide bars.
The present invention also relates to a method of mounting a knife against a seat in a granulator mill housing, the knife and a guide bar supporting the knife being screwed in position against the seat.
Granulator mill housings for granulators for use within the plastics industry are previously known in the art. Such granulator mill housings display as a rule a plurality of fixed knives for cooperation with corresponding knives on a rotor accommodated in the granulator mill housing. The fixed knives are generally screwed in position against seats in the granulator mill housing with the aid of screws and guide bars so that the knives are fixedly clamped between the guide bars and the seats of the granulator mill housing.
Granulators are manufactured in a plurality of different sizes, in which event—as regards larger granulators—both the guide bars and the knives will have considerable dimensions and as a result substantial weight, often together of the order of magnitude of between 20 and 30 kg. If a knife is difficult to access, for example on the underside of the granulator mill housing, it is almost impossible to mount such a knife in position for a single person. The reason for this is that it would entail that this person must handle two separate parts of considerable weight and manoeuvre them to the correct position so that the screws may be mounted in place.
It is desirable to design the granulator mill housing disclosed by way of introduction so that the drawbacks inherent in the prior art are obviated. In particular, it is desirable to design the granulator mill housing so that its knives and guide bars may simply and conveniently be mounted and dismounted by a single person.
It is also desirable to design the method disclosed by way of introduction so that the drawbacks inherent in the prior art technology are obviated. In particular, it is desirable to design the method so that the knives and guide bars may be mounted simply and conveniently by a single person.
A granulator mill housing according to an aspect of the present invention is characterised in that one of the seats is disposed at the underside of the granulator mill housing, that, in the area of this seat, there is provided a stand on which a guide bar may be laid in a preparatory position with its side intended for cooperation with a knife turned to face substantially upwards, and that the guide bar and knife resting thereon are together pivotal to a mounting position with the knife in abutment against the seat.
A method according to an aspect of the present invention is characterised in that the guide bar is placed on a stand in the region of the seat and is turned with its side intended for cooperation with the knife facing upwards, possibly with a knife already resting thereon, that, where applicable, the knife is placed on the surface of the guide bar intended for cooperation with the knife and that the guide bar and the knife, together and resting on the stand, are pivoted to a mounting position with the knife in abutment against the seat, and that the screws are mounted in position.
The present invention will now be described in greater detail hereinbelow, with reference to the accompanying Drawings. In the accompanying Drawings:
To the extent directional- and positional disclosures are used in the following description, these refer to directions and positions in the normal position of use of the granulator mill housing.
The granulator mill housing according to the present invention is principally intended for large granulators, where the distance between two end walls I included in the granulator mill housing may amount to more than 1 m. The end walls 1 have bearing housings 2 for journaling a rotor 4 in a rotor space 3 interiorly in the granulator mill housing.
It will be apparent from
The granulator mill housing has, in the illustrated embodiment, three fixed knives 7 which are fixedly clamped against corresponding seats 8 in the granulator mill housing with the aid of guide bars 9.
The continued description hereinbelow will be restricted to the knife placed on the underside of the granulator mill housing and its associated guide bar.
In the area of the knife placed at the underside of the granulator mill housing, there is provided a stand 10 in the form of a shelf or a plate which has a substantially horizontally aligned upper surface. The stand extends out from the wall of the granulator mill housing and is fixed thereto so that a free space is formed on the upper side of the stand.
The guide bar 9 has an elongate main portion 11 which has a surface 13 intended for cooperation with the knife 7. The guide bar further displays a wall portion 12 which, in the mounted position of the guide bar, forms a part of that defining wall which surrounds the rotor space 3. The free edge of the wall portion 12 facing away from the main portion 11 of the guide bar is, in the mounted position, located substantially straight beneath the rotational shaft 6 of the rotor 4.
As is best apparent from
As is apparent from
It will be apparent from the figures that, on the upper side of the stand 10, there is provided at least one, but preferably two upwardly directed pins 20. These pins 20 fit into the two centrally located apertures in the major portion 11 of the guide bar and thereby prevent relative slipping between the guide bar and the stand 10 when the guide bar is laid on the upper side of the stand.
As was mentioned above, the guide bar may simply be lifted in and placed on the stand 10 as shown in the right-hand half of
On dismounting of a knife, the screws 18 are first backed off, whereafter the knife and the guide bar are pivoted from the mounting position to the preparatory position, their weight still being taken up by the stand 10. In the final phase of this pivoting, the pins 20 will he accommodated in the two centrally located apertures in the main portion 11 of the guide bar so that slipping is prevented. At the same time, the bead 14 will be accommodated in the recess 16 and abut against its upper defining wall. This implies that the guide bar and the knife 7 rest in a stable position on the upper side of the stand 10. From this position, the knife can then be lifted down simply, as also applies to the guide bar 9.
For adjustment of the knife 7 in the radial direction, i.e. the distance between the edge of the knife and the edges of the knives 5 disposed on the rotor 4, there are provided set screws 22 at the seat 8 (
In the rear edge 22 of the knife, there are provided adjustment screws 23 which are adjusted in connection with grinding of the knife and which are placed for cooperation with the end surfaces of the set screws 21. The adjustment screws thus serve the purpose of compensating for such dimensional changes as occur on regrinding of a knife.
When a guide bar and a fixed knife resting thereon are pivoted from the preparatory position to the mounting position, there may be a certain risk that the adjustment screws 23 and the set screws 21 catch in one another so that the pivoting is obstructed or the knife 7 comes out of position. In order to avoid this risk, there are small heels provided on the surface 13 of the guide bar intended for cooperation with the knife, the heels preventing the knife 7 from sliding down before time against the set screws 21.
Number | Date | Country | Kind |
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0801650-3 | Jul 2008 | SE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/SE09/00342 | 6/30/2009 | WO | 00 | 12/8/2010 |