FR2698562A1 - Rotating shaver cutter assembly for comminuting machine - comprises shaft driven rotor carrying crown wheel with cutting box enclosed by casing with shaving inlet finished product outlet - Google Patents

Abstract

The rotor (1) which is driven by a shaft (2) carries a crown wheel with webs parallel to the axis. A cutting box (4) has two cutters which are also parallel to the axis surrounds the rotor. A casing (5) which encloses the cutter box has an inlet for the supply of shavings as well as an outlet for the finished cut product. Sealing parts close the chinks of the slot between the rotor and the cutter box. The sealing parts comprise segments assembled in a ring which are fixed to the rotor. ADVANTAGE - Allows rapid and easy replacement of seals.

Description

 The invention relates to a rotary chopper for shavings.

Known chip choppers of the type comprising a rotor driven by a shaft supporting a ring of fins parallel to the axis, a knife box with knives also parallel to the axis, which box surrounds the rotor, a housing closing the knife box and comprising an inlet for feeding the chips as well as an outlet for the finished chopped product, and sealing members which close the interstices of the slot between the rotor and the knife box
Such annular knife choppers have an annular slot between the outside diameter of the rotor and the inside diameter of the knife ring in the axial end region. This must be sealed so that the chips pass only in the radial direction through the knife box and do not exit laterally in the axial direction through the interstices of the slot. For this reason, sealing members are used. These consist of sheet metal rings and are embedded in corresponding recesses of the lateral flanges of the rotor and are fixed there by screws, so that their inner circumferential surfaces are adjacent to the inner circumferential surfaces of the knife box. The fact of being adjacent of course causes some wear of the sealing members, since the knife ring is usually fixed while the rotor is in rotation. Thus, the sealing members are wearing parts, which must be replaced from time to time.

 Their replacement is problematic, in that the sealing members mounted in a ring on the rotor are difficult to access and can absolutely not be disassembled in this position.

To replace the sealing elements, the complete rotor must therefore be removed. After replacing the sealing elements, the rotor must be reassembled, which takes considerable time.

 The invention consists in solving the problem of the design of a rotary chopper of the type mentioned above so that the replacement of the sealing members is easier and faster.

 This problem is solved by the following distinctive characteristics: the sealing members consist of segments assembled in a ring and, preferably, these segments assembled in a ring are fixed to the rotor.

The invention is explained in detail using the attached plates in which
Fig. 1 is a view, in reduction, of the face of a chopper, that is to say of the face on which the cover of the casing is located with the entry of the shavings
fig.2 is an axial section of the same chopper seen from the side on an enlarged scale
fig.3 is an enlargement of a detail of fig.2, and
Fig.4 shows some sealing segments which, when fitted, constitute a sealing element.

 As can be seen in detail, the rotary chopper is equipped with a rotor 1 which is driven by a shaft 2. The rotor 1 carries a ring of fins parallel to the axis. A knife box with knives 4 also arranged parallel to the axis, surrounds the rotor.

The rotor 1 and the knife box themselves are arranged in a casing 5, both being contained in the latter. The casing 5 has an inlet for the supply of chips as well as an outlet for the finished chopped product.

 In fig. 3, the shape and arrangement of the rotor, the knife box with the knives 4 and the sealing members 7 are even better recognized.

As can be seen, the rotor 1 has a multitude of fins of which only one fin 1.1 can be distinguished here. The fins are welded to the front walls 1.2.

and 1.3 which are perpendicular to the axis. The front wall shown on the left 1.3 only consists of a ring, so that there is a central annular opening 1.4.

for loading chopping chips. On the casing 5 of which only a part is seen, there is a hinged door 5.1. It also has a central opening 5.2. A hopper for loading chips which is not visible in this drawing is mounted on this door.

 The sealing members 7 are of particular importance in this context. They are composed of a plurality of sealing segments, the assembly of which each time forms a ring. The periphery of the annular sealing members 7 thus obtained is adjacent to the inner circumference of a knife-holding ring 4.1.

It is in this area that the sealing takes place and naturally also some wear. Fig. 4 shows how a sealing element 7 is composed of several sealing segments.

 Thanks to the inventive design of the sealing members, the replacement of the worn members by new members no longer presents any difficulty, since for this it suffices to open the door of the casing. The central opening of the front wall of the rotor which is located at this point is large enough to allow the fitter to introduce and replace the segments mounted on the rotor. Thus, disassembly of the rotor requiring a lot of time and work is no longer necessary.

Claims (2)

1.-Rotary chopper for shavings, comprising a rotor (1) which is driven by a shaft (2) and which comprises a ring of fins parallel to the axis, a knife box (4) which comprises knives also parallel at the axis which surrounds the rotor (1), a casing (5) enclosing the knife box and comprising an inlet for feeding the chips as well as an outlet for the finished chopped product, sealing members (7 ) which close the interstices of the slot between the rotor (1) and the knife box, characteristic  in that the sealing members (7) consist of segments assembled in a ring 2. Rotary chopper according to claim 1, characterized  by fixing to the rotor (1) the segments assembled in a ring.