Impact Comminutor

Abstract

An impact comminuter for bulky refuse comprises a housing for a toothed iller which rotates about a horizontal axis and propels material against an impact surface provided on a breaker plate which is yieldably mounted in the housing at a level above the impeller axis. The breaker plate has a serrated portion which is adjacent to the impeller and whose teeth define gaps for the teeth of the impeller. The front flanks of teeth on the serrated portion are either flush with the impact surface or are located downstream of such surface, as considered in the direction of rotation of the impeller. The front flanks and/or the lands of teeth on the serrated portion can be provided with serrations.

Description

BACKGROUND OF THE INVENTION

The present invention relates to impact comminutors in general, and more particularly to improvements in comminutors which can be utilized to break up bulky pieces of refuse, especially pieces of damaged furniture, mattresses or the like.

It is already known to employ an impact comminutor for crushing of garbage. Such comminutors, also called hammer crushers, normally comprise a toothed impeller or rotor which rotates in a housing and propels material against one or more breaker plates. A comminutor with yieldable breaker plates can be used for crushing of minerals as well as for crushing of bulky refuse which often contains hard-to-break parts, such as hinges, metallic posts or other hardware normally found in pieces of furniture, crates or like bulky goods. When the material is admitted into a relatively large chamber defined by the housing of the comminutor, it moves into the range of teeth or ribs on the revolving impeller and such teeth effect rapid comminution of material into small particles.

A drawback of presently known impact comminutors is that they are not suited for comminution of relatively soft and/or tough materials, such as rubber, fibers to be found in mattresses, or the like. Such materials must be broken up by tearing, not by impact, and the presently known comminutors are not provided with any effective means for tearing up fibers, rubber or the like. Attempts to convert conventional comminutors for treatment of elastic or fibrous materials include the provision of teeth on the impact surface or surfaces of one or more breaker plates. It was found that such proposals are unsatisfactory, especially when the teeth or like projections are provided on the impact surface of the foremost breaker plate. The teeth interfere with proper operation of the comminutor. Similar problems arise if the teeth or other types of projections are provided on the internal surface of the housing in the region ahead of the foremost breaker plate. This is due to the fact that a bulky piece is likely to prop itself against a projection in the housing or on the breaker plate and then extends across the path of material travel to block the progress of material toward and beyond the breaker plate or plates. Removal or shifting of such bulky pieces when the apparatus is in us is extremely dangerous and time consuming.

An object of the invention is to provide an impact comminutor which is sufficiently versatile to be capable of comminuting all kinds of goods, including those which consist of wood, ceramic, sheet metal, elastic material and/or fibers.

Another object of the invention is to provide an impact comminutor which is capable of effecting rapid and uniform comminution of elastic and/or fibrous materials, such as mattresses, fragments of tents or the like.

A further object of the invention is to provide the impact comminutor with teeth or analogous comminuting projections which are distributed and designed in such a way that they do not promote clogging of the apparatus and that they insure rapid, uniform and effective comminution of pieces of furniture, bedding or the like.

THe improved impact comminutor comprises a housing defining an internal chamber and having an inlet and an outlet, a rotary impeller mounted in the chamber of the housing in the path of material which is admitted through the inlet, and breaker means provided in the housing and including a first portion having an impact surface against which the bulk of admitted material is propelled by the impeller and a serrated second portion having a front surface which is located between the impeller and the impact surface. In accordance with a feature of the invention, the front surface of the serrated portion is at most flush with the adjoining part of the impact surface but can be placed behind such impact surface, i.e., downstream of the impact surface, as considered in the direction of rotation of the impeller.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved impact comminutor itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a sectional view of an impact comminutor which embodies the invention and includes a breaker means having two breaker FIG. 2 is an enlarged fragmentary sectional view of the serrated portion on the front breaker plate; and

FIG. 3 is a similar fragmentary sectional view of the serrated portion on the rear breaker plate.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates an impact comminutor which comprises a housing 1 defining an internal chamber which accommodates a driven drum-shaped impeller or rotor 2 rotating in a clockwise direction about a horizontal axis. The impeller 2 is provided with axially parallel rows of teeth 3. The drawing shows two rows of teeth 3; however, the impeller 2 may provided with a single row or with three or more rows of such teeth. An inlet 4 serves for admission of bulky pieces of refuse like materials, for example, pieces of furniture, mattresses, frames of beds or the like. The outlet of the housing is shown at 4a .

The chamber of the housing 1 further accommodates several breaker devices, also called breaker plates. These include a front breaker plate 6 and a rear breaker plate 12. The front breaker plate 6 includes an upper or outer portion 6a having an impact surface 6b which is located in the path of travel of material which enters the housing 1 through the inlet 4 and is propelled against the breaker portion 6a by teeth 3. In accordance with a feature of the invention, the breaker plate 6 further comprises a serrated second portion or rack 7 which is separately secured to the portion 6a by bolts 7a or analogous fasteners and is located between the impact surface 6b and the periphery of the impeller 2. The teeth 8 of the rack 7 form a row extending in the axial direction of the impeller 2 and defining between themselves gaps or clearances 8a for the teeth 3. The front flanks 9 of the teeth 8 together from a front surface of the rack 7 and such front surface is at most flush with the adjoining part of the impact surface 6b , as considered in the direction of rotation of the impeller 2. Thus, the flanks 9 are either flush with the substantially radially extending inner part of the impact surface 6b or are offset in a direction to the right, i.e., downstream as seen in the direction of travel of the teeth 3. The first portion 6a of the breaker plate 6 is pivotally secured to the housing, as at 6c, and is connected with an adjusting spindle 10 which extends beyond the top wall of the housing 1 and serves as a means for changing the position of the breaker plate 6 with reference to the impeller 2. Material which is admitted by way of the inlet 4 can be furnished by a suitable conveyor, for example, by a vibrating chute or the like, not shown. The housing 1 includes a downwardly inclined wall 5 which guides admitted material into the range of teeth 3 on the impeller 2.

The second or rear breaker plate 12 comprises a first portion 12a having an impact surface 12b and mounted on a horizontal pivot 12c, and a serrated second portion 7' which is secured to the portion 12a by fasteners 7a 'and has teeth 11 whose front flanks 9'are positioned with reference to the impact surface 12b in the same way as described in connection with the flanks 8 of teeth 7. It will be noted that the teeth 11 have serrated top lands 11A which face the peripheral surface of the impeller 2. The teeth 11 also form a row and define between themselves gaps for the teeth 3. The serrated portions 7, 7' extend through an angle of in the circumferential direction of the impeller 2, at least 15 degrees.

If desired, the front flanks 9 and 9' can be serrated, as indicated at 9A in FIG. 2, to further enhance the comminuting action of the apparatus. The serrations on the top lands 11A of teeth 11 serve a similar purpose.

FIG. 1 further shows a second adjusting spindle 10' which can be manipulated from the exterior of the housing 1 to change the position of the breaker plate 12 with reference to the impeller. Adjustments in the position of the breaker plate 6 and/or 12 with reference to the impeller 2 will be carried out, when necessary, in order to influence the comminuting action. If desired, the breaker plates 6, 12 can be interchanged, and it is equally within the purview of the present invention to provide the breaker plate 6 with the serrated portion 7' and/or to provide the breaker plate 12 with the serrated portion 7. Furthermore, the apparatus can be provided with a single breaker plate 6 or 12; two or even more breaker plates are normally desirable to effect more intensive breaking action before the fragments reach the outlet 4a .

The operation of the improved impact comminutor will be readily understood. The impeller 2 is driven by an electric motor or the like (not shown) and the aforementioned chute delivers material to the inlet 4 so that such material descends along the sloping wall 5 and moves into the range of teeth 3. Such teeth propel the material against the front breaker plate 6 where the material undergoes an intensive comminuting action on impact against the surface 6b and against the front surface 9 of the serrated portion 7. The mounting of the breaker plate 6 is such that it can yield (by pivoting about the axis of the member 6c ) if the pressure against its portion 6a and/or 7 exceeds a predetermined value. The fragments which develop on impact against the surface 6 and 9 are further comminuted by teeth 3 and are caused to move beyond the breaker plate 6 to be propelled against the surfaces 12b, 9' of the second breaker plate 12.

In the illustrated apparatus the inlet 4 and the breaker plate 6 and 12 are located at a level above a horizontal plane which includes the axis of the impeller 2. The configuration of teeth 8, 11 on the serrated portions 7, 7'is preferably such that these teeth do not have any horizontal facets, flanks or surfaces which could serve as supports or abutments for fragments of comminuted material.

It was found that the improved apparatus is capable of breaking up bulky pieces as well as of comminuting bodies which consist (entirely or in part) of soft and/or tough materials for example, rubber, fibers or the like. It was further found that such soft or tough materials cannot clog the apparatus and that they are subjected to a very intensive and uniform comminuting action.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of the above-described contribution to the art.

Claims

What is claimed as new and described to be protected by Letters Patent is set forth in the appended claims:

1. In an impact comminutor, particularly for crushing of bulky refuse or like material, a combination comprising a housing having an inlet; an impeller having beating means, said impeller being rotatable about an axis and being mounted in said housing in the path of material which is admitted by way of said inlet into said housing; and at least one breaker means provided in said housing, said breaker means including a first portion having a plane impact surface directed toward said axis and against which the admitted material is impelled by said impeller and a second serrated portion between said impeller and said impact surface, said second portion being provided with teeth which are spaced in the direction of said axis and which extends substantially in the direction of rotation of said beating means, said teeth having front surfaces which are at most flush with the adjoining part of said impact surface as considered in the direction of rotation of said impeller.

2. A combination as defined in claim 1, wherein said teeth defining between themselves gaps and wherein said beating means are teeth which pass through said gaps in response to rotation of said impeller.

3. A combination as defined in claim 2, wherein each of said teeth has a face facing said impeller and including with the front surface of the respective tooth an angle of less than 90.degree..

4. A combination as defined in claim 2, wherein the teeth of said serrated portion have serrated lands facing said impeller.

5. A combination as defined in claim 1, wherein said serrated portion extends along an angle of at least 15.degree., as considered in the direction of rotation of said impeller.

6. A combination as defined in claim 1, further comprising second breaker means located past said first-mentioned breaker means, as considered in the direction of rotation of said impeller.

7. A combination as defined in claim 6, wherein the teeth of said second breaker means are longer in the direction of rotation of said impeller than those of said first breaker means.

8. A combination as defined in claim 14, further comprising means for adjusting the position of said breaker means with reference to said impeller.

9. A combination as defined in claim 1, wherein said impeller is rotatable about a substantially horizontal axis and wherein said breaker means is located at a level above a horizontal plane which includes said horizontal axis.

10. A combination as defined in claim 1, further comprising fastener means separably securing said serrated portion to said first portion.