GB2098503A

GB2098503A - Stripper device for shredding machines

Info

Publication number: GB2098503A
Application number: GB8209523A
Authority: GB
Original assignee: Feinwerktechnik Schleicher and Co
Current assignee: Feinwerktechnik Schleicher and Co
Priority date: 1981-03-31
Filing date: 1982-03-31
Publication date: 1982-11-24
Also published as: FR2502979A1; BR8201813A; DE3112666A1; NL8201357A; DE3112666C2; GB2098503B; CH655865A5; BE892673A; JPS57174153A; NL192089C; LU84049A1; NL192089B; JPS613533B2

Abstract

This invention relates to stripper devices 10 engaging in the gap between bladed discs 7,8 of a shredding machine each bladed disc 7, 8 having a separate stripper device 10 fastened on the housing in non- rotatory and positionally secured manner. The surface of each stripper bears close to a spacing disc 9 on the outer periphery thereof along a sector portion which may be about 70 DEG . The stripper device 10 may have a square-section excision 12 traversed by a square-section shaft 11 which is fastened to the housing. <IMAGE>

Description

SPECIFICATION Stripper device for shredding machines The present invention relates to stripper devices within the ripping mechanism of a shredding machine for text and data carriers, which comprises two parallel cutting shafts assuming a mutual spacing, on which are corotatorily installed bladed discs having a mutual axial spacing, between which are situated spacing discs of lesser diameter, stripper projections engaging in the gap between the bladed discs.

Hereinafter such stripper devices will be referred to as "of the kind described".

It is an object of the invention to provide a stripper device of the kind described which is smaller than those previously drawn, but with a similar driving performance.

Accordingly, in a stripper device of the kind described the invention consists in that a separate stripper device, which is mounted on the housing in non-rotatory and positionally secured manner and the surface of which bears close to the spacing disc on the outer periphery of the spacing disc along a sector portion, is allocated to each bladed disc at least at the trailing extremity of the ripping mechanism.

Thus stripper devices according to the invention are no longer attached to the spacing discs but engage the spacing discs radially from the outside and their surface bears close to the spacing disc on the outer periphery of the spacing discs over at least a particular sector portion. Very acute peeler edges may thereby be obtained, which accomplish an extremely satisfactory removal of the material, which runs towards the output end of the ripping mechanism in the gap between the bladed discs. The peeler edge may to this end be constructed with an acute angle of less than 30 degrees, thereby resulting in an excellent material lifting property.

It is possible to install the stripper device on the housing of the ripping mechanism in an economical manner. Provision is made for this purpose for the stripper device to have a squaresection excision which is traversed by a squaresection spindle which is secured to the housing.

This results in a fastening of the stripper devices which can transmit great forces and bending moments, the stripper devices themselves being manufacturable from an inexpensive material of small dimension.

A resultant advantage is a particularly economical production of stripper devices of this nature, which may be made by inexpensive stamping operations.

In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings illustrating only one embodiment, by way of example only and in which: Figure 1 shows a vertical cross-section through a ripping mechanism comprising stripper devices in accordance with the invention, and Figure 2 shows a plan view and partial crosssection of the ripping mechanism according to Figure 1.

Referring now to the drawings, one embodiment of a ripping mechanism comprising two cutting shafts 1, 2 is shown in Figure 1.

Bladed discs 7, 8 are attached in manner known per se on each cutting shaft 1, 2 in co-rotatory and positionally secured manner. In the present case, each cutting shaft has a turning groove 3, 4 wherein engage co-ordinated punched-out lugs 5, 6 of the bladed disc 7, 8 in question. The mutual spacing of the bladed discs 7, 8 in Figure 2 is obtained by means of interposed spacing discs 9.

To this end, the stripper devices bear on the outer periphery of the spacing disc along a sector portion of approximately 45-90 degrees (approximately 70 degrees in the present example). This results in low friction between the spacing disc and the stripper devices since areas of small size only are exposed to frictional contact. The motor performance may also be reduced substantially on this score, as related to an identical cutting performance, so that a more economical production is possible.

To this end, the stripper device 10 is mounted on a square-section spindle 11 , the stripper device 10 comprising a square-section excision 12 which is traversed by the square-section spindle 11 identically formed in outline. The square-section spindle 11 is non-rotatorily installed on the housing by means of two securing bores 1 3. By virtue of the arrangement of the square-section spindle 11 comprising the securing bores 13, which passes through a corresponding excision 1 2 of the stripper projection 10, a highly stressable mounting of the stripper device 10 is obtained.

Another advantage is that a peeler edge 14 is formed, which displays an extremely satisfactory stripping action. This peeler edge 14 is present on all stripper projections, four stripper devices 10 being present in the present embodiment, each stripper device 10 comprising two peeler edges 14. If the ripping mechanism runs in reverse as a matter of fact, the other peeler edges 14 act to strip off the material running in reverse.

The forming of two peeler edges for each stripper device is however required only if use is made of a ripping mechanism provided with a reversing gear.

In the embodiment of Figures 1 and 2, the material which is to be shredded is fed in between the bladed discs 7, 8 in the direction of the arrow 1 5, is fragmented by the intermeshing bladed discs 7,8 of the two cutting shafts 1 and 2, and leaves the ripping mechanism at the output extremity 1 8 in the direction of the arrow 1 6.

The stripper devices 10 may be made as inexpensive stampings, and the peeler edges 14 may be punched out very sharply by application of a punching tool without another and special subsequent machining operation being required.

Claims

1. A stripper device of the kind described,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Stripper device for shredding machines The present invention relates to stripper devices within the ripping mechanism of a shredding machine for text and data carriers, which comprises two parallel cutting shafts assuming a mutual spacing, on which are corotatorily installed bladed discs having a mutual axial spacing, between which are situated spacing discs of lesser diameter, stripper projections engaging in the gap between the bladed discs. Hereinafter such stripper devices will be referred to as "of the kind described". It is an object of the invention to provide a stripper device of the kind described which is smaller than those previously drawn, but with a similar driving performance. Accordingly, in a stripper device of the kind described the invention consists in that a separate stripper device, which is mounted on the housing in non-rotatory and positionally secured manner and the surface of which bears close to the spacing disc on the outer periphery of the spacing disc along a sector portion, is allocated to each bladed disc at least at the trailing extremity of the ripping mechanism. Thus stripper devices according to the invention are no longer attached to the spacing discs but engage the spacing discs radially from the outside and their surface bears close to the spacing disc on the outer periphery of the spacing discs over at least a particular sector portion. Very acute peeler edges may thereby be obtained, which accomplish an extremely satisfactory removal of the material, which runs towards the output end of the ripping mechanism in the gap between the bladed discs. The peeler edge may to this end be constructed with an acute angle of less than 30 degrees, thereby resulting in an excellent material lifting property. It is possible to install the stripper device on the housing of the ripping mechanism in an economical manner. Provision is made for this purpose for the stripper device to have a squaresection excision which is traversed by a squaresection spindle which is secured to the housing. This results in a fastening of the stripper devices which can transmit great forces and bending moments, the stripper devices themselves being manufacturable from an inexpensive material of small dimension. A resultant advantage is a particularly economical production of stripper devices of this nature, which may be made by inexpensive stamping operations. In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings illustrating only one embodiment, by way of example only and in which: Figure 1 shows a vertical cross-section through a ripping mechanism comprising stripper devices in accordance with the invention, and Figure 2 shows a plan view and partial crosssection of the ripping mechanism according to Figure 1. Referring now to the drawings, one embodiment of a ripping mechanism comprising two cutting shafts 1, 2 is shown in Figure 1. Bladed discs 7, 8 are attached in manner known per se on each cutting shaft 1, 2 in co-rotatory and positionally secured manner. In the present case, each cutting shaft has a turning groove 3, 4 wherein engage co-ordinated punched-out lugs 5, 6 of the bladed disc 7, 8 in question. The mutual spacing of the bladed discs 7, 8 in Figure 2 is obtained by means of interposed spacing discs 9. To this end, the stripper devices bear on the outer periphery of the spacing disc along a sector portion of approximately 45-90 degrees (approximately 70 degrees in the present example). This results in low friction between the spacing disc and the stripper devices since areas of small size only are exposed to frictional contact. The motor performance may also be reduced substantially on this score, as related to an identical cutting performance, so that a more economical production is possible. To this end, the stripper device 10 is mounted on a square-section spindle 11 , the stripper device 10 comprising a square-section excision 12 which is traversed by the square-section spindle 11 identically formed in outline. The square-section spindle 11 is non-rotatorily installed on the housing by means of two securing bores 1 3. By virtue of the arrangement of the square-section spindle 11 comprising the securing bores 13, which passes through a corresponding excision 1 2 of the stripper projection 10, a highly stressable mounting of the stripper device 10 is obtained. Another advantage is that a peeler edge 14 is formed, which displays an extremely satisfactory stripping action. This peeler edge 14 is present on all stripper projections, four stripper devices 10 being present in the present embodiment, each stripper device 10 comprising two peeler edges 14. If the ripping mechanism runs in reverse as a matter of fact, the other peeler edges 14 act to strip off the material running in reverse. The forming of two peeler edges for each stripper device is however required only if use is made of a ripping mechanism provided with a reversing gear. In the embodiment of Figures 1 and 2, the material which is to be shredded is fed in between the bladed discs 7, 8 in the direction of the arrow 1 5, is fragmented by the intermeshing bladed discs 7,8 of the two cutting shafts 1 and 2, and leaves the ripping mechanism at the output extremity 1 8 in the direction of the arrow 1 6. The stripper devices 10 may be made as inexpensive stampings, and the peeler edges 14 may be punched out very sharply by application of a punching tool without another and special subsequent machining operation being required. Claims

1. A stripper device of the kind described, wherein a separate stripper device, which is mounted on the housing in non-rotatory and positionally secured manner and the surface of which bears close to the spacing disc on the outer periphery of the spacing disc along a sector portion, is allocated to each bladed disc at least at the trailing extremity of the ripping mechanism.

2. A stripper device as claimed in claim 1, which has a square-section excision traversed by a square-section shaft which is fastened to the housing.

3. A stripper device as claimed in claim 1 or 2, which terminates in a peeler edge at its surface close to the spacing disc.

4. A stripper device as claimed in claim 3, wherein the apex angle of the peeler edge is less than 30 degrees.

5. A stripper device as claimed in any of claims 1 to 4, which consists of a stamping.

6. A stripper device substantially as hereinbefore described with reference to the accompanying drawings.

7. A ripping mechanism which includes a stripper device as claimed in any of the preceding claims.

8. A shredding machine incorporating a ripping mechanism as claimed in claim 7.