EP0778087A1 - Small-sized document shredder - Google Patents

Abstract

The shredder consists of a casing in lower and upper parts, containing endface bearing plates and scraper elements. The bearing plate (3) for the shredding rolls (4, 5) on the drive side also serves as the one-piece bottom (3a) of a bowl-shaped transmission casing (3, 3a, 3b) which can be closed by a cap (3c). The whole shredding unit, including the scraper battens, a mounted in the lower part (2) of the casing in the region of the endface bearing plates (3, 8) on vibration damping elements (9).

Description

The invention relates to a small document shredder according to the preamble of claim 1.

Such small devices are known, for example, from DE 40 08 654 A1 and have two-part injection molded parts Plastic housing, into which the mostly web-shaped wiper elements together with the cutting roller bearings are also integrated during spraying. From all this, however, the ease of installation results in the disadvantage that the known devices run very uneasily and are loud because all drive and working noises are transmitted as vibrations to the housing, which also acts as a reinforcing soundboard.

The object of the present invention is therefore also to create an extremely easy-to-assemble small document shredder with extremely low structure-borne noise emission and great smoothness.

The object is achieved in a device according to the preamble of claim 1 by the structural features specified there in the characterizing part of the claim. The sub-claims contain advantageous refinements and developments of the inventive concept, which are also shown in detail in the drawings and are described in more detail below.

Fig. 1

in weitestgehend schematischer Darstellung die Ansicht auf das Unterteil eines geöffneten Aktenvernichtergehäuses und

Fig. 2

in gegenüber Fig. 1 vergrößerten Maßstab eine Querschnittsdarstellung gemäß der dortigen Linie A-A.

Show it:

Fig. 1

in a largely schematic representation, the view of the lower part of an open document shredder housing and

Fig. 2

on a larger scale than in FIG. 1, a cross-sectional view along the line AA there.

The shredder shown in the form of a small device consists in its basic structure of a shell-like, the cutting rollers 4, 4a and 5, 5a together with their front bearing plates 3 and 8, the associated wipers 6 and 7 and the clippings outlet gap "SA" containing the lower housing part 2 and an upper housing part 1 which can be placed thereon and provided with the cutting material feed gap "MZ".

The key to achieving the object set with the invention in such a device is that the drive-side bearing plate 3 for the cutting rollers 4, 5 at the same time the one-piece bottom 3a of a likewise shell-like gear housing 3, 3a, 3b which can be closed by a cover 3c forms and the entire cutting unit (gear housing 3, Cutting rollers 4, 5 and scrapers 6, 7) are mounted in the area of its front bearing plates 3 and 8 in the lower housing part 2 via vibration-damping elements 9. These two measures give the entire cutting unit a high degree of intrinsic stability and manufacturing accuracy, and due to the vibration-damping "acoustic" decoupling from the housing, there is practically no structure-borne noise radiation and thus extremely quiet and quiet operation.

In a further embodiment of this new basic design it is also provided that the cutting rollers 4, 4a and 5, 5a and their comb-like wiper strips 6, 7 are non-positively and / or positively connected by plugging into corresponding recesses with the two end bearing plates 3 and 8; This results in an extremely easy-to-assemble and service-friendly production method, which also enables the prefabrication of individual assemblies for later completion.

In terms of function, it is also important for the new cutting unit that the stripper strips 6, 7 consist of a plain bearing plastic and lie closely on the cutting roller core 4a and 5a and are supported on the cutting rollers 4, 5 and the free ends 4b and 5b of the contact area of the wipers 4 and 5 are nose-shaped on the roller core 4a and 5a. This gives the scraper combs their necessary stability. In order to prevent paper from getting into the gap between the cutting unit and the upper housing part 1 during material feed or especially when the roller is returning, it is further provided that the surfaces 6a and 7a of the wiper strips 6 and 7 are arranged across their entire length with mutually spaced transverse webs 11 have and the upper housing part 1 has corresponding recesses 12 which engage without touching each other (acoustic decoupling).

Another essential feature of the cutting unit design can be seen in the fact that the undersides 6b and 7b of the wiper strips 6 and 7 each have a longitudinal web 6c and 7c which engages in a corresponding recess 13a in the bottom housing longitudinal member 13, the latter in the open bottom region 2c of the Lower housing part 2 are located and have guide surfaces 13b which run obliquely downward from the cutting rollers 4, 5. On the one hand, this configuration prevents a build-up of dust and cut material particles in the housing area and also, since the small devices generally do not have a "bag full" shutdown, prevents the material to be cut from entering the cutting unit from below when the material container "SB" is full; This effect is also supported by a baffle-like gradation 13c of the underside of the longitudinal beams 13 and the projecting corner designs or edges "K" of the wiper strips 6 and 7 in the area of the clippings exit gap "SA". These longitudinal edges "K" of the stripper strips 6 and 7 are also based on the cutting roller center axis "M" deeper "a _1" as the dimension "a" up to the Abstreiferoberfläche 6a and 7a. Ultimately, the functional completion of the entire device also includes the on / off switch 14 together with its switching lug 14a protruding into the material feed gap "MZ" for automatic cutting unit start-up during material feed.

Reference list

1

Upper part of the housing

2nd

Lower part of the housing

2a

vertical partition

2 B

Bearing and guide bar (for item 9)

2c

open floor area

3rd

gearbox-side bearing plate

3a

Bottom of the gearbox

3b

Side part of the gearbox

3c

cover

3d

Snap lock

4th

Cutting roller

4a

Roll core

4b

pointed nose

5

Cutting roller

5a

Roll core

5b

pointed nose

6

Wiper strip

6a

surface

6b

bottom

6c

Longitudinal web

7

Wiper strip

7a

surface

7b

bottom

7c

Longitudinal web

8th

end bearing plate

9

elastic damping element

10th

Drive motor

11

Crossbar

12th

Recess

13

Housing side member

13a

Recess

13b

Guide surface

13c

gradation

14

On / off switch

14a

Switch flag

15

"Snap in" element

a

distance

a ₁

distance

K

protruding edge

M

Central axis

MZ

Material feed gap

SAT

Cuttings exit

SB

Clippings container

Claims (10)

Small document shredder, consisting of a shell-like housing lower part which contains the cutting rollers together with their front-side bearing plates and wiper elements and a housing upper part which can be placed thereon and is provided with the material feed gap,
characterized,
that the drive-side bearing plate (3) for the cutting rollers (4, 5) also forms the one-piece bottom (3a) of a likewise shell-like gear housing (3, 3a, 3b) which can be closed by a cover (3c) and the entire cutting mechanism (gear housing) 3, cutting rollers 4, 5 and wipers 6, 7) in the area of its end bearing plates (3 and 8) via vibration-damping elements (9) in the lower housing part (2). Small document shredder according to claim 1,
characterized,
that the cutting rollers (4, 5) and their comb-like wiper strips (6, 7) are non-positively and / or positively connected by plugging into corresponding recesses with the two end bearing plates (3 and 8). Small document shredder according to claims 1 and 2,
characterized,
that the scraper strips (6, 7) consist of a plain bearing plastic and lie closely on the cutting roller core (4a and 5a) and are supported on the cutting rollers (4, 5). Small document shredder according to claim 3,
characterized,
that the free ends (4b and 5b) of the contact area of the wipers (4 and 5) on the roller core (4a and 5a) are nose-shaped. Small document shredder according to claims 1 to 4,
characterized,
that the surfaces (6a and 7a) of the wiper strips (6 and 7) have transverse webs (11) arranged along their entire length with mutual spacing from one another and the upper housing part (1) has corresponding recesses (12) which do not touch one another (acoustic Uncoupling), interlock. Small document shredder according to one or more of the preceding claims,
characterized,
that the undersides (6b and 7b) of the scraper strips (6 and 7) each have a longitudinal web (6c and 7c) which engages in a corresponding recess (13a) in the bottom housing side member (13). Small document shredder according to claim 6,
characterized,
that the longitudinal frame members (13) lie in the open bottom region (2c) of the lower housing part (2) and have guide surfaces (13b) which run obliquely downwards from the cutting rollers (4, 5). Small document shredder according to claims 6 and 7,
marked by
a baffle-like gradation (13c) of the underside of the side members (13) and an additional projecting corner formation of the edges (K) of the underside of the scraper bars (6b and 7b) in the area of the clippings outlet gap (SA). Small document shredder according to claim 8,
characterized,
that the longitudinal edges (K) with respect to the cutting roller center axes (M) are lower (a ₁ ) than the dimension (a) from the centers (M) to the stripper surface (6a and 7a). Small document shredder according to one or more of the preceding claims,
marked by
Assignment of an on / off switch (14) to the upper housing part (1) with a switching lug (14a) protruding into the cut material feed gap (SZ) and so-called "snap-in" elements (15) for connecting the upper and lower housing parts (1 and 2 ).

Images