Trimming and/or fin cutting tools with interchangeable cutting edges

The present disclosure relates to a trimming and/or fin cutting tool for removing ridges, burrs and casting seams of the kind having interchangeable cutting edges, preferably made of hard metal, in which one or more cutting lines of the tool is or are formed by a number of cutting plates (1) detachably mounted on the vertical side (3) of a tool body (2). The tool enables the rational use of the detachable cutting plates and is characterized mainly in that the cutting plates are reversible and are attached to the tool body (2) in a plane directed in the working direction of the tool, the cutting plates having spaces between them to form gaps (6) for the passage of chips. Preferably, the cutting plates along the or each cutting line are attached to the tool body (2) in rows at different heights relative to a base, the separate effective cutting edges of the cutting plates (1) along a common cutting line being arranged to overlap each other.

The present invention relates to a method of providing trimming and/or fin 
cutting tools with interchangeable cutting edges, preferably made of hard 
metal. 
In the field of casting, the cleaning of cast products is an increasingly 
accentuated problem. Formerly it was, and it still is, a normal practice 
to chisel and/or machine away ridges, burrs, and so-called casting seams 
on cast products. By "casting seams" are meant those material 
accumulations on the products which occur when a casting melt flows out of 
the mould during a casting process and penetrates into joints at the 
surface of separation of the like. Removal of ridges, burrs, and similar 
casting seams by the above-mentioned methods results in the formations of 
dust and considerable noise. These environmental disadvantages, together 
with increasing demands on the appearance of the finished cast goods, as 
well as rising wages in the workshops has resulted in more rational 
cleaning processes being sought. As an essential part of this search a 
large number of cleaning machines have been developed and many attempts 
have also been made to use machines to smooth off the ridges and burrs, on 
cast products. 
In fin cutting or other treatments where material is removed in a machine 
such as a hydraulic, pneumatic or mechanical press, the most 
heavily-loaded parts of the tool, that is to say the edges, are generally 
made of a harder and stronger material which is hard-soldered to a holder 
or the like means attached to the tool. Therefore, every tool is thus 
adapted to its particular purpose. As the tool is used the edge is worn 
away and has to be sharpened. After being sharpened a number of times, the 
tool is unusable and requires expensive repairwork if the tool is to be 
fit for use again. 
An object of the present invention is to eliminate said disadvantages and 
to create a system which makes it possible to rationalise the use of 
detachable cutting plates made of hard metal in trimming and/or fin 
cutting tools, in which system each separate cutting line of the tool is 
formed by a number of cutting plates detachably mounted on a tool body. 
The invention is characterised mainly in that the cutting plates are 
reversible, and are attached to the tool body in a plane directed in the 
working direction, the cutting plates having spaces between them to form 
gaps for the passage of chips. The invention makes it possible to turn or 
replace the cutting plates individually when local damage occurs on a 
composite cutting edge. 
In accordance with the invention, the cutting plates along the or each 
cutting line are attached to the tool body in rows at different heights 
relative to a base, the separate effective cutting edges of the cutting 
plates along a common cutting line being arranged to overlap each other. 
Preferably, each individual cutting plate is attached to the tool body in a 
plane such that the cutting angle relative to the horizontal plane is at 
least 12.degree..

In the fin cutting tool illustrated in FIG. 1 a number of cutting plates 1 
are fitted securely in a tool body 2 so that, as a whole, they enclose a 
rectangular area and provide four composite cutting lines. Each such 
cutting line is formed by the co-action of the cutting edges of the plates 
1 acting along the said line. Each cutting plate 1 is of triangular shape 
and is attached to the tool body in a plane directed in the working 
direction and with one apex 1a foremost. Each cutting plate 1 is, in a 
conventional manner, shaped with so-called relief angles, which means that 
one triangular base plane is larger than its other triangular plane 
because the side surfaces 1b of the plate are formed with so-called 
reliefs between the said base planes. As will be seen clearly from FIG. 2 
the cutting plates 1 are arranged in this embodiment in two rows at 
different heights relative to the working material. This means that the 
separate effective cutting edges 4 along a common cutting line are 
preferably arranged to overlap each other. Thus, the total length of a 
common cutting line comprises an appropriate number of overlapping cutting 
plates 1 and it will be appreciated that it is possible to readily adapt 
the tool to a great extent in dependence upon the particular requirements. 
By varying the relative height locations of the two rows of cutting 
plates, it is possible to vary the gaps between the individual cutting 
plates 1 and, thereby, the total length of a cutting line can also be 
varied. The overlap a (FIG. 2) which the plates 1 take up relative to each 
other provides great flexibility for a common cutting line, and this also 
affords better cutting conditions when carrying out a fin cutting 
operation. Such a result depends partly on the fact that the total force 
during the introduction of the fin cutting operation is distributed over a 
smaller number of contact points, and partly on the fact that each 
separate cutting edge has a marked inclination relative to the working 
material which is to be cut. 
Referring to FIG. 3, the cutting plates 1 are preferably attached with 
counter-sunk screws 5 in the usual way, but in certain cases it may also 
be expedient to provide in the tool body 2 fixed shoulders, stops or the 
like against which the cutting plates 1 are supported. 
This facilitates the mounting of the cutting plates 1 and it also means 
that the fixing screws for the cutting plates 1 are subjected to less 
stress when cutting operations are being carried out. 
The transition into the corner between two cutting lines which meet each 
other can be formed in a number of different ways without losing the 
adaptability to different products which is characteristic of the 
invention. 
In the embodiment described above, the individual cutting plates 1 are of 
the same size and same triangular shape and are attached to the tool body 
with their planes directed in the working direction of the tool. However, 
it will be appreciated that within the scope of the invention different 
sizes and/or shapes of cutting plates may be used in any desired 
combination, to suit particular requirements. Thus, the cutting plates 1 
may equally-well be made four-sided, preferably with a rectangular or 
square base shape, possibly in different sizes, since this affords many 
installation possibilities and increases the number of reversible cutting 
edges available. Between the cutting plates 1, it is also necessary that 
gaps 6 be provided for the free passage of swarf chips while cutting is 
being carried out. In this instance, with the embodiment described above, 
care must be taken to ensure that each actual cutting line is located 
nearest the tool body 2. 
Due to the use of detachable reversible cutting plates 1, a significantly 
increased working life is achieved for the trimming and fin cutting tools. 
At the same time it is also possible to achieve significant savings due to 
the fact that, in the manufacture of a tool in accordance with the 
invention, it is possible to a large extent to use modular units and 
fixings. This means that the shapes and dimensions of the cutting plates 1 
can be chosen to suit a specific modular system, for example, determined 
by the number and spacing of fixing holes in the tool body 2 for the 
cutting plates 1, or to suit cassette-type cutting units which, when fixed 
to a tool, form together a total cutting edge. In this instance a 
longitudinal cutting line may have a configuration like that shown in FIG. 
2, in which every second cutting plate 1 occupies a raised position 
between two lower plates. Within the scope of the invention, however, 
other configurations may also be chosen for the cutting plates 1, and it 
is also possible to choose other shapes for the detachable cutting plates 
1. 
The invention is therefore not limited to the embodiment shown by way of 
example, but can be modified to provide alternative versions within the 
scope of the following patent claims.