[0001] The present invention generally relates to the cutters with cutting inserts for working
wood or similar and it refers, more particularly, to a cutter for working wood comprising
a monoblock portion.
[0002] Nowadays, cutters with cutting inserts, also called knives, are known; said knives
are shaped according to the need and are singularly placed and fixed inside related
slots formed peripherally in the body of the cutter with desired angles.
[0003] The cutter comprises a main body able to be rotated and a series of knives mounted
on the periphery of the cutter body and having a substantially radial arrangement.
[0004] Since the knives, when they work the wood, are subjected to a tilting moment in the
opposite direction with respect to the advancement, due to the resistances they encounter
in cutting the piece being worked and due to the centrifugal force deriving from the
rotation of the cutter, each of said knives is blocked in the cutter's body so as
to counteract said forces and to ensure a precise and permanent arrangement of the
structure; usually, each knife is removably coupled with the cutter's body at a relative
slot, by means of one or more locking elements or blocks and of at least one screw,
which locks the knife on a wall of said slot with pressure.
[0005] In view of the fact that the knives must be periodically replaced, it is important
that the milling tools allow a quick and easy assembly and disassembly of the knives,
even on the machine, while still ensuring an accurate and stable locking on the main
body of said machine, also by considering the high cutting speeds and the subsequent
high centrifugal forces which are generated.
[0006] Another drawback of the known milling tools is the complexity and bulkiness of the
cutter body, as well as the difficulty in throwing away the wooden chips removed from
the knives during processing, with the consequent frequent cleaning operations of
the tool, which are necessary especially when said tool works at high speeds and/or
with relevant cutting depth. The object of the present invention is therefore to overcome
the above mentioned drawbacks and, in particular, to provide a cutter for working
wood, which allows performing different cutting, engraving and/or shaving operations.
[0007] Another object of the present invention is to provide a cutter for working wood,
which has a reduced number of components, with respect to the prior art, and which
therefore has a considerable construction economy, as well as greater precision in
the processing, with respect to the known structures and techniques.
[0008] Another object of the present invention is to provide a cutter for working wood,
which allows the operator to replace the knives more comfortably and quickly, even
when the tool is still mounted on the machine, with respect to the known cutters.
[0009] A further object of the present invention is to provide a cutter for working wood,
which has a smaller bulk and greater precision, by performing the same processing,
with respect to the known cutters.
[0010] The above mentioned and other objects, according to the present invention, are achieved
by making a cutter for working wood, according to the alleged claim 1; other detailed
technical features of the cutter according to the present invention are present in
the dependent claims.
[0011] Further characteristics and advantages of the cutter for working wood, which is the
object of the present invention, will become more clear from the following description,
which refers to a preferred but not limitative embodiment of the wood cutter and which
refers to the attached drawings, in which:
- figure 1 shows a perspective view of a known milling tool for working wood;
- figure 2 shows a perspective view of a cutter for working wood, according to the present
invention;
- figure 3 shows an enlarged detail of the cutter shown in figure 2;
- figures 4, 5 show respective side views of the cutter shown in figure 2;
- figure 6 shows a cross-section of the cutter of figure 2;
- figures 7A, 7B show a schematic enlargement of the detail indicated with J in figure
4, respectively in a rest position and in a position for extracting the cutting insert
of the cutter, according to the invention;
- figures 8A, 8B and 8C show respective side views of a first embodiment of the cutting
insert used in the wood cutter, according to the present invention;
- figures 9A, 9B show two perspective views of the cutting insert shown in the previous
figures;
- figures 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H and 10I show a series of cross-sectional
views of further embodiments of the cutting insert used in the wood cutter, according
to the present invention.
[0012] With particular reference to the figure 1, a known cutter 10 has at least two bodies
10A, 10B, preferably made of steel or aluminum alloy and preferably having a substantially
cylindrical shape; the bodies 10A, 10B have a series of slots or peripheral seats
11, where respective removable tools consisting of cutting inserts or knives 12 are
housed and locked.
[0013] As can be directly seen from the alleged figure 1, the bodies 10A, 10B of a known
cutter 10 have as many peripheral slots 11 as there are knives 12 to be used and each
knife 12 is singularly fixed in a respective slot 11.
[0014] The number of knives 12 depends on the number and quality of the operations to be
performed (cutting, engraving, shaving, etc.) and each knife 12 is removable from
its seat by acting axially and from above, by means of a special key which acts on
a respective screw locking 13; therefore, the greater are the number of knives 12
used, the greater are the complications regarding accessibility to the locking screws
13 for replacing the worn knives 12 with other new sharpened knives.
[0015] In order to overcome this drawback, the cutter according to the present invention
comprises a single body 20, which is substantially cylindrical, and one or more cutting
inserts or knives 22 which are inserted in respective seats 21 formed radially in
the body 20 in correspondence with an edge identified by at least two offset horizontal
planes of the body 20; advantageously, the edge is identified by a horizontal plane
24 of the cutting body 20 projecting or retracting with respect to a further horizontal
plane 25 of said cutting body 20 (as shown in detail in the alleged figures 2, 3,
4, 5 and 6).
[0016] Moreover, each knife 22 has a substantially cylindrical portion 35, which is inserted
in the seat 21, and an elongated shaped portion 26 which is configured to perform
different wood working operations, so that a single cutting insert or knife 22 is
used to make incisions, cuts, shavings, etc. Figures 8A, 8B, 8C, 9A and 9B show a
first embodiment of a shaped cutting insert or knife 22, which is configured to perform
cutting, engraving and shaving operations in wood, while figures 10A, 10B, 10C, 10D,
10E, 10F, 10G, 10H and 10I show different embodiments of the cutting insert 22 and
the relative mutual positioning of said cutting insert 22 with respect to the cutter's
body 20.
[0017] Moreover, the knife 22 has an appendix or central wedge 27, formed between the cylindrical
portion 35 and the elongated shaped portion 26, on which a block 28 abuts during the
knife 22 replacement operation.
[0018] The replacement operation takes place by inserting a special key 29 inside a double-threaded
grain 30, placed inside the block 28, which allows to move the block 28 and push the
knife 22 out of the seat 21, thanks to the stop of the block 28 on the wedge 27 of
the knife 22 (as shown in detail in the attached figures 7A and 7B, where, in particular,
F1 indicates the direction of rotation of the key 29, which in turn causes the vertical
movement of the knife 22, thus releasing said knife 22 from the housing 20 of the
cutter's body 20).
[0019] It has thus been found that the solution object of the present invention allows to
achieve the aforementioned objects and, in particular, allows to use a single cutter
body and a single insert to perform wood processing (smoothing, incisions, cuts, etc.),
also allowing the cutter to work at high peripheral speeds required by the new machinery
with an increase in productivity and a good finish; the cutting insert is interchangeable
and has a radial fixing, so as to obtain further advantages in terms of accessibility
for the operator during maintenance operations and/or replacement of the cutting inserts.
[0020] Further advantages resulting from the use of a wood cutter according to the present
invention are constituted by the fact that less tolerances are detected during the
manufacture of the cutter, with respect to the prior art, so that the cutters have
more assembled bodies where the relative cutting inserts are housed.
[0021] The technical features of the wood cutter according to the present invention are
therefore clear from the above description, as well as the related advantages.
[0022] In particular, said advantages relate to the following technical aspects:
- cutter with a single body;
- accessory (cutting insert) of a substantially cylindrical shape;
- radial installation of the cutting insert.
[0023] Finally, it is clear that numerous variations can be made to the wood cutter of the
present invention, without departing from the novelty principles inherent in the inventive
idea of the appended claims, just as it is clear that, in the practical embodiment
of the invention, materials, shapes and dimensions of the technical details may be
any according to requirements and said details may be replaced with other technically
equivalent ones.
1. A wood cutter, characterized in that it comprises a single body (20) of substantially cylindrical shape and one or more
cutting inserts or knives (22), which are inserted in respective seats (21) formed
radially in said body (20) in correspondence with a corner identified by at least
two staggered horizontal planes which are obtained on said body (20).
2. The cutter according to claim 1, characterized in that said corner is identified by a first horizontal plane (24) of said body (20) of the
cutter, which is projecting or re-entering with respect to a second horizontal plane
(25) of said body (20).
3. The cutter according to at least one of the previous claims, characterized in that each knife (22) has a substantially cylindrical portion (25), which is inserted in
one of said seats (21), and an elongated portion (26), which is adapted to make different
working on wood, such as incisions, cuts, shaves, etc.
4. The cutter according to claim 3, characterized in that each knife (22) has a central end or wedge (27), which is obtained between said substantially
cylindrical portion (25) and said elongated portion (26), on which abut a dowel (28)
during a knife replacement operation (22).
5. The cutter according to claim 4, characterized in that a double threaded grain (30) is placed inside said dowel (28) and in that a suitable key (29) is inserted inside said grain (30) so as to move said dowel (28)
and thus to push said knife (22) out of said seat (21), by advancing said dowel (28)
which therefore abuts on said wedge (27) of the knife (22).