EP0487948A2 - Method and device for placing surface channels in panels of soft material and use of the device - Google Patents

Abstract

A method and a device serve for placing surface channels (82) of at least approximately rectangular cross-section in panels of soft material, in particular mineral-fibre insulating mats (80) or panels of a styrene polymer. A motor-driven cutting tool (10) with oscillating cutting knife (20) is used. The cutting knife (20) has sections which are angled with respect to one another and are provided at least partly with a cutting edge. The cutting edge runs around over at least three or two sections, which together form a U or L. The cutting knife (20) is taken through the panels in an approximately straight line (83). …<IMAGE>…

Description

The invention relates to a method for introducing surface channels with an at least approximately rectangular cross section in sheet material made of soft material, in particular mineral fiber insulation mats or sheets made of a styrene polymer, in which a motorized cutting tool with an oscillating cutting knife is used.

The invention further relates to a device for introducing surface channels with an at least approximately rectangular cross section in sheet material made of soft material, in particular mineral fiber insulation mats or sheets made of a styrene polymer, with a motor-driven cutting tool, in which a cutting knife about an axis with an angular amplitude in Range between about 0.5 ° and 7 ° and a frequency in the range of about 10,000 to 25,000 min ⁻¹ is oscillating and the cutting knife has angled sections that are at least partially provided with a cutting edge.

Finally, the invention relates to a use of the above-mentioned device.

From the DE prospectus "FEIN Elektro-Fugenschneider" (1989) it is known to use a cutting tool for cutting open joints filled with soft material in buildings, in which a cutting knife with a frequency of approximately 20,000 rpm by 2 ° angle swings back and forth. The knife has a rectangular or triangular top view blade with a pointed tip.

In practice, such electric floor cutters have sometimes been used to cut surface channels in sheet material made of a soft material, especially in aluminum-clad fiberglass insulation mats. Surface channels of this type are provided there in order to create space for lines, for example water, gas or electrical lines.

For this purpose it is known to make two parallel cuts through the surface of the plate material with the above-described electric floor saw and then between the Remove the material that has remained in both parallel cuts, for example using a conventional pocket knife or a screwdriver.

This known procedure is very time-consuming, because a total of three operations are required, namely two cutting operations and a process of separating material, the latter operation in particular being complex because the material to be removed on the underside still has to be detached from the surrounding material, since there - on the sole of the canal to be trained - no material was cut. It is also obvious that such a manual procedure can only be used very inaccurately, because it is hardly possible, particularly under the rough conditions at a construction site, to make two cuts that are exactly parallel and of the same depth, and then using a screwdriver or another relatively simple tool to remove the remaining material to an exactly the same and constant depth.

On the other hand, renovation and expansion work, in particular also modernization work on old buildings, is increasingly being carried out, in which glass fiber insulation mats are used to fill wooden structures, for insulation and the like. With all these "small" construction projects in the course of modernizations or when creating new living space in attics, basements or the like, the problem mentioned, to introduce surface ducts in fiberglass insulation mats, is becoming ever greater.

From DE-OS 37 19 073 a cutting tool of the type already explained is also known, in which an oscillating cutting knife is also used. In this well-known Cutting tool, the cutting knife has a 90 ° bent blade, the two legs of which are each provided with a cutting edge. This known cutting knife is provided for the sole purpose of cutting through elastic adhesive beads on vehicle windows. This special tool is neither intended nor suitable for other areas of application. In particular, this tool is unsuitable for introducing surface channels into soft material plate material because the outer leg of the blade extends parallel to the lower surface of the power tool and the oscillating shaft forms an acute angle with the cutting edges, so that cutting into surfaces of plate material is impossible is.

The invention is based on the object of developing a method and a device of the type mentioned at the outset, or of specifying a use with which it is possible to introduce surface channels into plate material made of soft material in a short time and in a simple and reproducible manner.

According to the method mentioned in the introduction, this object is achieved on the one hand in that a U-shaped cutting knife, the cutting edge of which rotates around the sections forming the U, is guided in a straight line through the plate material.

According to the method mentioned in the introduction, this object is achieved in that, in a first step, an L-shaped cutting knife, the cutting edge of which rotates around the sections forming the L, is guided essentially in a straight line through the plate material, and in a second step Cutting knife with a straight section is guided parallel to the guidance of the first step through the plate material such that a continuous strip of plate material can be removed from the plate material.

In the latter case, in order to introduce wide surface channels, the first and second steps are preferably carried out several times in succession, in parallel and next to one another.

According to the device mentioned at the outset, the object on which the invention is based is achieved, on the one hand, by the cutting edge rotating over at least three sections which form a U with one another.

According to the device mentioned at the outset, the object on which the invention is based is achieved in that the cutting edge rotates over at least two sections which form an L with one another.

Finally, the object on which the invention is based is still achieved by the use of a device of the type mentioned at the outset for introducing surface channels with an at least approximately rectangular cross section in sheet material made of soft material, in particular mineral fiber insulating mats.

The object underlying the invention is completely achieved in this way.

The U-shaped knife of the one embodiment according to the invention with a total of at least three cutting edges namely causes a complete surface channel to be cut out in a single operation, the cutting line leading from surface to surface.

This ensures that the channel cut out is of constant width and depth over its entire length, so that, depending on the number and size of the lines to be laid, the desired channel can be produced in a single operation when a suitable knife is selected. This needs just attach the tool once and be guided over any length along the desired course of the channel.

The L-shaped knife of the other embodiment according to the invention with a total of two cutting edges causes two sides of the surface channel to be cut out in a first operation, while the third side is subsequently cut out in a second operation. This has the advantage that surface channels of any width can be produced by performing the two work steps as often as desired next to one another and in parallel. The L-shaped knife is then used to cut out a further strip of material on the underside on one side of the channel which has already been cut out, which strip is cut in the longitudinal direction in a further second operation and can be removed or dropped out.

In both cases, the cut-out material residue can only be removed from the cut channel, but does not need to be separated out, so that in practice no operation is required at all, because the cut-out material migrates out of the cut-out channel by itself or with an inclined work surface falls out.

Compared to the previous procedure, this results in a drastic time saving, on the one hand because only one or two work steps are required, and on the other hand because the channel introduced has a target dimension over its entire length that is sufficient for all lines reliably record.

In a preferred embodiment of the device according to the invention, at least one of the sections forming the free ends of the U is followed by a further section which is angled by approximately 90 °.

If the angled section extends outwards from the clamping side, this measure has the advantage that the further section can serve as a support on the surface of the plate material, so that when the surface channel is cut, the knife cannot sink into the plate material in an uncontrolled manner becomes.

In a particularly preferred embodiment, the angled section is provided at the outer, free end of the section forming the U, extends towards the clamping side and is supported on one of the sections on the clamping side. Since the outer part of the cutting edge is thus additionally supported, the mechanical stability of the cutting edge is considerably improved in this way.

Furthermore, a possible risk of breakage due to wear of the cutting edge in the region of the bent section is avoided.

The support can be achieved in a simple manner in that the angled section is welded to one of the sections on the clamping side, which can be achieved, for example, by spot welding.

In further preferred configurations of the device according to the invention, the cutting knife comprises a blade holder for inserting an exchangeable blade.

This measure has the advantage that with one and the same blade holder, surface channels of different widths, depths or other contours can be cut in close succession, with only minimal changeover times being required.

It is particularly preferred in this embodiment if the blade is U-shaped and can be locked with its free ends in slots in the blade holder.

Then, in particular, several parallel slots can be provided in the blade holder for introducing channels of different widths and / or latching means can be provided for introducing channels of different depths, which allow the free ends to be locked in the slots at different heights. This applies in particular when the latching means are designed as tongues in the slots which engage in counter-slots in the free ends.

All of these measures have the advantage that surface channels of different widths and / or different depths can be cut in a few simple steps. In the latter exemplary embodiments, surface channels of different depths can even be produced with one and the same blade.

In the exemplary embodiments in which an L-shaped cutting knife is used, it is particularly preferred if, as an alternative to the L-shaped cutting knife, a non-angled cutting knife can be inserted into the cutting tool.

This measure has the advantage that the strips of material that have already been loosened on one or both sides on the second or third side can be cut out with a straight, non-angled cutting knife.

In embodiments of the invention, the cutting edge is not straight at its cutting edge, but rather is serrated or wavy.

This measure has the advantage that the invention can be used with particular advantage even with such material made of soft material which is relatively coarse in structure. A typical example of such a material are the styrene polymers, as are commercially available, for example, under the registered trademark STYROPOR. In the case of such materials, when using cutting blades with a straight cutting edge, the spheres of material from which the structure of the material is composed may jump out uncut when cutting. This has the disadvantage that an unclean cut edge arises, but on the other hand also pollutes the area in the area of the cut more than necessary. It has now been shown that in such cases, in particular when the cutting knife with a straight cutting edge is somewhat blunted, an effective remedy can be created by using serrated or wavy cutting edges. The distance between the individual prongs or waves is preferably so large that it is larger than the diameter of the beads in the case of a styrene polymer.

In these exemplary embodiments of the invention with a serrated or wavy cutting edge, it is particularly preferred if the cutting knife is provided with a smooth cutting edge on one side in a cutting direction and with a serrated or wavy cutting edge on the other side in the opposite cutting direction.

This measure has the advantage that one and the same tool can be used for two different materials. If the tool with the clamped cutting knife is to be used in a fibrous material, it only needs to be guided through the material with the smooth cutting edge in one cutting direction, while with another, rather coarse material, the tool in the opposite cutting direction with the serrated or wavy edge is passed through the material. This is a great advantage, particularly when it comes to interior fittings, if, on the one hand, mineral fiber mats and, on the other hand, styrene polymer sheets are used, one after the other, in succession, both of which are known to be used for thermal insulation. The craftsman then does not need to change the cutting knife, but rather can process both materials with an unchanged tool, only the tool having to be guided through the material once in one direction and the other in the other direction.

In further embodiments of the invention, the cutting edge runs in an arc shape, preferably along a convex arc. This measure also has the advantage that a better cut is produced in numerous applications, be it with straight or serrated or wavy cutting edges along the arc shape.

Further exemplary embodiments of the invention are distinguished by cutting knives in which at least one of the sections provided with a cutting edge is tapered.

This embodiment of the knives also has advantages in terms of cut quality in numerous applications.

Finally, exemplary embodiments of the invention are preferred in which the axis is perpendicular to a first one Clamping section of the cutting knife adjacent and provided with the cutting edge extends.

This known measure has the advantage that the motor-driven cutting tool can be guided with its longitudinal axis perpendicular to the surface of the material, which is ergonomically advantageous in numerous applications and ensures good access to the material.

Further advantages result from the description and the attached drawing.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the combination specified in each case, but also in another combination or on their own without departing from the scope of the present invention.

Fig. 1

eine perspektivische Ansicht eines vorderen Teils eines Ausführungsbeispiels einer erfindungsgemäßen Vorrichtung;

Fig. 2 und 3

das beim Ausführungsbeispiel der Fig. 1 verwendete Schneidmesser, in Seitenansicht und in Draufsicht;

Fig. 4 und 5

Ansichten, ähnlich den Fig. 2 und 3, jedoch für ein etwas abgewandeltes Ausführungsbeispiel eines Schneidmessers;

Fig. 6

in vergrößertem Maßstab und in perspektivischer Ansicht ein weiteres Ausführungsbeispiel eines Schneidmessers, wie es im Rahmen der vorliegenden Erfindung verwendet werden kann;

Fig. 7

in ebenfalls perspektivischer Ansicht eine Prinzipskizze zur Erläuterung eines Schneidvorganges, wie er im Rahmen der vorliegenden Erfindung durchgeführt werden kann;

Fig. 8

eine Seitenansicht, ähnlich den Fig. 3 und 5, eines weiteren Ausführungsbeispiels eines Schneidmessers, wie es im Rahmen der vorliegenden Erfindung verwendet werden kann;

Fig. 9

eine Variante des Ausführungsbeispiels der Fig. 8;

Fig. 10

eine Seitenansicht des in Fig. 8 dargestellten Schneidmessers, jedoch um 90° gedreht;

Fig. 11

eine weitere Darstellung, ähnlich den Fig. 8 und 9 eines Schneidmessers, wie es ebenfalls im Rahmen der vorliegenden Erfindung verwendet werden kann;

Fig. 12

eine Seitenansicht des in Fig. 11 dargestellten Schneidmessers, jedoch um 90° gedreht;

Fig. 13

eine Variante des in Fig. 12 dargestellten Ausführungsbeispiels;

Fig. 14

eine weitere Variante des in Fig. 12 dargestellten Ausführungsbeispiels;

Fig. 15

eine Seitenansicht einer Variante des in Fig. 9 gezeigten Ausführungsbeispiels;

Fig. 16

eine Seitenansicht des Ausführungsbeispiels gemäß Fig. 15, jedoch nach Drehung um 90°;

Fig. 17

eine Seitenansicht einer weiteren Variante des Ausführungsbeispiels gemäß Fig. 2;

Fig. 18

eine Seitenansicht des Ausführungsbeispiels gemäß Fig. 17, jedoch nach Drehung um 90°;

Fig. 19

eine Seitenansicht einer weiteren Variante des Ausführungsbeispiels gemäß Fig. 15;

Fig. 20

eine Seitenansicht des Ausführungsbeispiels gemäß Fig. 19, jedoch nach Drehung um 90°;

Fig. 21

eine Seitenansicht einer weiteren Variante des Ausführungsbeispiels gemäß Fig. 17 und

Fig. 22

eine Seitenansicht des Ausführungsbeispiels gemäß Fig. 21, jedoch nach Drehung um 90°.

Embodiments of the invention are shown in the drawing and are explained in more detail in the following description. Show it:

Fig. 1

a perspective view of a front part of an embodiment of a device according to the invention;

2 and 3

the cutting knife used in the embodiment of Figure 1, in side view and in plan view.

4 and 5

Views, similar to Figures 2 and 3, but for a slightly modified embodiment of a cutting knife.

Fig. 6

on an enlarged scale and in perspective view, another embodiment of a cutting knife, as can be used in the context of the present invention;

Fig. 7

likewise in a perspective view, a schematic diagram for explaining a cutting process as can be carried out in the context of the present invention;

Fig. 8

a side view, similar to Figures 3 and 5, of another embodiment of a cutting knife, as it can be used in the present invention;

Fig. 9

a variant of the embodiment of Fig. 8;

Fig. 10

a side view of the cutting knife shown in Figure 8, but rotated by 90 °.

Fig. 11

a further representation, similar to Figures 8 and 9 of a cutting knife, as it can also be used in the context of the present invention;

Fig. 12

a side view of the cutting knife shown in Figure 11, but rotated by 90 °.

Fig. 13

a variant of the embodiment shown in Fig. 12;

Fig. 14

another variant of the embodiment shown in Fig. 12;

Fig. 15

a side view of a variant of the embodiment shown in Fig. 9;

Fig. 16

a side view of the embodiment of FIG 15, but after rotation by 90 °.

Fig. 17

a side view of another variant of the embodiment of FIG. 2;

Fig. 18

a side view of the embodiment of FIG 17, but after rotation by 90 °.

Fig. 19

a side view of another variant of the embodiment of FIG. 15;

Fig. 20

a side view of the embodiment of FIG 19, but after rotation by 90 °.

Fig. 21

a side view of another variant of the embodiment of FIG. 17 and

Fig. 22

a side view of the embodiment of FIG. 21, but after rotation by 90 °.

In Fig. 1, 10 denotes an electric tool with a housing 11, which is only indicated schematically and broken off. A front drive flange 12 is connected to the housing 11, which preferably contains an electric drive motor, which flange e.g. can contain an angular gear. The drive flange 12 is also provided with a protective bracket 13.

An axis 14 extends at right angles to the longitudinal axis of the housing 11 and is at the same time the axis of a drive spindle 15 in the drive flange 12. A double arrow 16 indicates that the drive spindle 15 moves in an oscillating manner, ie rotates back and forth by a small angular amount. The angular amount is approximately between 0.5 ° and 7 °, the oscillation frequency between 10,000 and 25,000 rpm.

A cutting knife 20 is inserted into the drive spindle 15, the further details of which are shown in FIGS. 2 and 3. The cutting knife 20 comprises a first, flat section 21, which is followed by a second, inclined section 22. This is followed by a third, flat section 23, from which a fourth section 24 extends vertically downward.

The fourth section 24 merges via a fifth section 25 bent by 180 ° into a sixth section 26 running vertically upwards. The upper free leg of the sixth section 26 merges again into a seventh section 27 which runs flat and is directed towards the third section 23.

A cutting edge 29 is fitted continuously in the fourth, fifth and sixth sections 24, 25, 26, which together form a U-shaped structure.

The first, flat section 21 merges to the right in FIGS. 2 and 3 into a circular extension 30 which is provided with a central driving profile 31, for example a polygon, which forms a torsionally rigid driving connection for the drive spindle 15.

4 and 5 show a slightly modified exemplary embodiment of a cutting knife 20a, in which the first to third sections 21a to 23a are combined to form a common inclined section which runs at an angle 35 of, for example, 15 ° with respect to a horizontal plane.

The cutting knife 20a also has a U-shaped shape, but does not have a flat section at the left free end of the U in the illustration in FIGS. 4 and 5, as is present in the embodiment of FIGS. 2 and 3 with 27 .

In the embodiment of FIGS. 4 and 5, a cutting edge 29a goes around the three sections of the U.

6 shows a further exemplary embodiment of a cutting knife 40.

The cutting knife 40 has a blade holder 41 which can be brought into a rotationally fixed driving connection with the drive spindle 15, for example with the aid of a circular section, as can be seen at 30, 31 in FIG. 3. For the sake of clarity, however, this is not shown again in FIG. 6.

The blade holder 41 has a first, inclined section 42 and a second, flat section 43. Slits 45a, 45b, 46a, 46b are made in the flat section 43, the total number of which is a multiple of 2. The slots 45a, 45b, 46a, 46b are arranged in pairs in a folding symmetry to one another.

It can thus be seen that the slots 45a, 45b, 46a, 46b each represent a U-shaped opening in the second, flat section 43 in plan view, the slots 45a, 45b on the left in FIG. 6 being arranged symmetrically with respect to the two right slots 46a, 46b are.

Each of the slots 45a, 45b, 46a, 46b has a continuous longitudinal wall 50 and 52 and, on the opposite side, a tongue 51 and 53 directed against the longitudinal wall 50, 52. In the case of the slots 45a on the left in FIG. 6 and 45b the tongues 51a, 51b are directed to the right, over the tongues 53a, 53b of the two slots 46a, 46b located on the right in FIG. 6 are directed opposite to the left.

The cutting knife 40 further comprises a separate, U-shaped blade 60. The blade 60 has a first, vertical section 61, a second, flat section 62 adjoining it below, and a third, in turn adjoining and vertically running section 63. The three sections 61, 62, 63 mentioned are in turn provided with a continuous cutting edge 64a or at the opposite end 64b.

The free ends of the vertical sections 61 and 64 are provided with horizontally extending slots 70 and 71, respectively. The width of the slots 70, 71 is equal to or slightly larger than the width of the tongues 51 and 53, respectively, while the total width of the vertical sections 61, 63 is equal to or slightly smaller than the total width of the U-shaped slots 45 and 46 is.

Because of this, it is possible to insert the blade 60 with the free ends of the vertical sections 61, 63 from below into an associated pair of U-shaped slots in the second, flat section 43 of the blade holder 41. The arrangement is preferably such that the vertical sections 61, 63 of the blade 60 are moved slightly towards one another with the fingers of the user, that is to say are pressed together, as indicated by a double arrow 75 in FIG. 6. In this position, the free ends of the vertical sections 61, 63 can be guided past the tongues 51, 53 of the slots 45, 46 until a desired depth of cut T is achieved by inserting said free ends into the slots 45, 46. If one releases the pressure exerted on the free ends (arrows 75) again, the free ends move apart again due to the elasticity of the blade 60 and the tongues 51, 53 can drop into the respective slot 70 or 71. The free ends of the vertical Sections 61, 63 of the blade 60 then rest elastically and possibly with a certain pretension on the incisions opposite the longitudinal walls 50, 52 on both sides of the tongues 51, 53 and are locked there.

In the embodiment shown in Fig. 6, the blade 60 has a width B, so that the slots 45a, 46a are to be used, which are also spaced apart by the dimension B.

If blades of greater width are to be used, the slots 45b, 46b, spaced further apart, are provided for this purpose. In a corresponding manner, the cutting depth T can be varied by changing the slot 70, 71 in engagement in each case. For this purpose, one and the same blade 60 can be used, while different blades usually have to be used for different widths B.

Regardless of which of the described cutting knives 20, 20a or 40 or which of the mentioned blades 60 is used, the manner of use is the same.

7 shows a section of an extremely schematically indicated sheet material made of soft material, namely a glass fiber or rock wool insulation mat 80. The mat 80 is provided on a flat surface with an aluminum liner 81, as is usually used as a vapor barrier in such insulation mats becomes.

FIG. 7 shows, as an example, the case in which a cutting knife 20 is used, as has already been shown and explained in FIGS. 1 to 3.

The cutting knife 20 is connected to the drive spindle 15 of the power tool 10 and the drive is then switched on. The cutting knife 20 then oscillates with the values mentioned at the beginning. The cutting knife 20 can now either be brought laterally to the mat 80 to insert a channel 82 or can be dipped at any location into the surface 84 of the mat 80 in order to cut out a surface channel 82 from the material of the mat 80.

In the example shown in Fig. 7, the cutting knife 20 is guided so that the third and seventh, each flat section 23 and 27 of the cutting knife 20 is guided along the surface 84 of the mat 80 so that it serves as a vertical stop and an undefined sinking of the cutting knife 20 into the mat 80 is prevented. The oscillating cutting knife 20 is now guided in a straight line along the surface 84, as indicated by an arrow 83 in FIG. 7. It goes without saying that "straight" means that a predetermined course of the channel to be formed is followed, which of course can also be curved at least in places. The term "rectilinear" is therefore only intended to illustrate that the channel 82 to be formed is an elongated structure.

In Fig. 8, 90 denotes another embodiment of a cutting knife. The special feature of this cutting knife is that a first straight section 91, which is used to fasten the cutting knife 90 to the power tool 10 of FIG. 1, passes straight into a second section 92 of the cutting knife, that is to say it is not angled or bent. The second section 92 is followed by a third, curved section 93, which in turn merges into a fourth, straight section 94 which runs parallel to the second section 92. The side view of FIG. 10, which is rotated by 90 ° with respect to the view of FIG. 8, shows the resulting shape of a U.

The second, the third and the fourth section 92, 93, 94 are provided with a cutting edge which runs over all three sections 92, 93, 94. The cutting edge 95 is serrated.

The serrated design of the cutting edge 95 is particularly advantageous for coarsely structured materials, e.g. Styrene polymers as are generally known under the registered trademark "STYROPOR". Such materials consist of material balls with a diameter of 1 or more mm. If such materials are cut with straight or already blunted knives, the material balls are not cut but rather jump out of the material elastically when cutting. This leads to unclean cut edges and contamination in the area around the work place. It has now been found that such materials can advantageously be cut with serrated or corrugated cutting edges, in particular when the distance between the serrations or waves is at least as large as the diameter of the beads.

From Fig. 8 it can also be seen that the cutting edge 95 is bent in the longitudinal direction. In the solid representation, the arc is convex, but it goes without saying that a concave arc can also be used for certain applications, as indicated in FIG. 8 by the dot-dash line at 95a.

Another variant of a cutting knife 90 ', as shown in FIG. 9, is finally provided with a straight cutting edge 95b. 9 corresponds completely to the cutting knife 90 of FIG. 8. Accordingly, the side view of FIG. 10 rotated by 90 ° is the same in all cases.

In FIG. 9 it is also indicated with 95b 'that the cutting knife 90' can be provided with different cutting edges on the right and left side in FIG. 9. While the right side in FIG. 9 is provided with a straight but serrated cutting edge 95b, the left side in FIG. 9 is also provided with a straight but smooth cutting edge 95b '. This is to indicate that the cutting knives, regardless of their other shape in the two possible cutting directions right / left can be provided with different cutting edges 95b and 95b ', so that one and the same cutting knife 90' can be used for cutting two different materials can and only the cutting direction, ie the direction in which the tool is guided must be changed.

In Fig. 10, 96 denotes an axis about which the cutting blades 90 and 90 'execute the oscillating movement.

Looking at the illustration in FIG. 1, it can be seen that, in the electromotive cutting tool 10 that is preferably used, the oscillating drive axis 14 is at an angle of 90 ° to the longitudinal axis of the housing 11. Therefore, if one of the cutting knives 90, 90 'shown in Figs. 8-10 is used with this cutting tool 10, the cutting edges 95 and 95b are aligned with the longitudinal sections 92 and 94 in extension of the longitudinal axis of the cutting tool 10 while they are being cut in the previously described embodiments with the longitudinal axis of the cutting tool 10 included an angle of 90 °.

However, it goes without saying that this differentiation is only to be understood as an example. Of course, the cutting knives 90, 90 'of FIGS. 8 to 10, like the cutting knives to be described below, can also be designed in an angled or cranked arrangement, similar to FIGS. 1 to 7 his and the same applies vice versa for the previously described exemplary embodiments of FIGS. 1 to 7, which can also be designed in a non-angled or non-angled embodiment.

The use of the cutting knives 90, 90 'according to FIGS. 8 to 10 is otherwise identical to that of the previously described cutting knives of FIGS. 1 to 7.

In contrast, FIGS. 11 to 14 show further exemplary embodiments of cutting knives, the shape of which in side view is not U-shaped but L-shaped or even straight.

11 shows a cutting knife 100 with a first, straight fastening section 101, to which in turn a second, likewise straight section 102 is directly connected. In this respect, the arrangement corresponds to the sections 91, 92 of the cutting knife 90 according to FIG. 8.

The second, straight section 102 of the cutting knife 100 is now provided with a cutting edge 103 which is corrugated in the exemplary embodiment shown. Here, too, the considerations apply, which have already been made above with regard to FIGS. 8 to 10 with regard to wavy or serrated cutters, and it is also understood here that the design of the cutting edges is only to be understood as an example, because all of them are described in the context of the present invention Cutting knives with continuous, serrated or wavy cutting edges, whether straight or curved.

In a first variant of the cutting knife 100 shown in FIG. 11, as shown in FIG. 12, a cutting knife 100 ′ is only provided with the second straight section 102. In a further variant according to FIG. 13, a cutting knife 100 '' Provide a third, also straight section 104 at the lower free end of the second straight section 102 with an angle of 90 °. In a third variant according to FIG. 14, a cutting knife 100 '''is provided at the lower end of the second straight section 102 with a likewise angled third section 104a, which, however, adjoins the second straight section 102 at an obtuse angle.

At 105 in FIG. 12 it is again indicated that the cutting knives 100 of FIGS. 11 to 14 oscillate about an axis which runs at 90 ° to the cutting edge 103 of the second straight section 102, similarly to the way in FIG. 10 above with reference to FIG Axis 96 has been described.

The cutting knives 100 of FIGS. 11 to 14 are used in different ways compared to what was described above for FIGS. 1 to 10.

In order to cut a surface channel into a plate material with the cutting knives of FIGS. 11 to 14, two operations are required.

First, an angled cutting knife 100 '' or 100 '''is used to make a first longitudinal cut through the plate material. As a result, the surface channel is already cut out on two of three sides. The third side of the surface channel is then cut out in a further work step, either in which an angled cutting knife 100 '' or 100 '''is passed through the plate material in the opposite direction, so that essentially the cutting edge 103 on the second straight section 102 cuts out the third side of the surface channel. Alternatively, the second can also be used 12, a straight cutting knife 100 'can be used to cut out the third side of the surface channel.

If surface channels that are wider than the width of the third, angled section 104 are desired, the two work steps can then be repeated one or more times. The angled cutting knife 100 ″ is then guided through the surface channel that has already been introduced, in which the second, straight section 102 slides on one of the side walls of the surface channel and the third, angled section 104 laterally carries out a further horizontal cut. The material strip which has already been loosened on one side in this way is then in turn separated by a second cut using the cutting knife 100 ″ or 100 ′.

15 to 22 show further exemplary embodiments of the invention in which additional support of the free leg of the U-shaped cutting edge is provided.

The cutting knife generally designated by the number 110a in FIGS. 19 and 20 essentially corresponds to the cutting knife according to FIGS. 9 and 10, but an additional support of the outer free leg of the U-forming section is provided on the clamping-side section. The cutting knife 110a has a first flat section 112a, on which a circular extension with a driving profile 120a in the form of a polygon is provided. The driving profile 120a is used for connection to the drive spindle 15 of the power tool 10, by means of which the cutting knife 110a can be moved in an oscillating manner about the axis 118a. The first flat section 112a merges into the U-shaped cutting edge 119a, which is formed from a part of the first section 112a, from a curved section 113a and a third flat section 114a, which is parallel to the first section 112a. The third flat section 114a continues with a section 115a angled at an angle of approximately 90 ° in the direction of the first flat section 112a. The fourth angled section 115a is followed by another fifth section 116a angled at an angle of approximately 90 °, which runs parallel to the first flat section 112a. The fifth section 116a lies on the first flat section 112a and is connected to it by a spot weld 117a. The U-shaped cutting edge 119a is thus closed off at the upper end via the fourth and fifth sections 115a, 116a and is supported on the first section 112a.

This results in a significantly improved stability of the cutting edge 119a and a considerably reduced risk of breakage.

The cutting edge 119a is serrated as in the previously mentioned exemplary embodiment according to FIGS. 9 and 10.

The total in Figs. 15 and 16 with the point. The embodiment designated 110 differs from the previously described embodiment according to FIGS. 19 and 20 only in that the cutting edge 119 is straight and has no serrations. The cutting edge 119 tapers towards both ends of the cutting knife 110, so that a cut in both directions is possible.

17 and 18 show a modification of the exemplary embodiment according to FIGS. 2 and 3.

The cutting knife 140 comprises a first, flat section 142, which is followed by a second, inclined section 143. This is followed by a third, vertical section 144 which merges into a fourth section 145 which is bent by 180 °. At the end of the curved section 145 is included another section 146 perpendicular to the first section 142 and running parallel to the third section 144.

The U-shaped cutting edge 151 is formed by the two legs of the third section 144 and the fifth section 146, as well as by the bent section 145 lying between them. The fifth section 146 at its end remote from the bent section 145 merges at right angles into a sixth angled section 147, which is followed by a further inclined section 148. This inclined section 148 abuts the second inclined section 143 and is connected to it by a spot weld 119. In this way, the U-shaped cutting edge 151 is also supported on the clamping side via the angled section 147 and the inclined section 148, so that greater stability is achieved and the risk of breakage is reduced. The cutting edge 151 is formed on both sides on the sections 144, 145, 146, so that the cutting knife 140 can be used in both cutting directions.

The exemplary embodiment denoted overall by the number 140a in FIGS. 21 and 22 differs from the exemplary embodiment described with reference to FIGS. 17 and 18 only in that the cutting edge 151a is designed in a serrated manner. Although the cutting edge 151a is only formed on one side of the cutting knife 140a in the exemplary embodiment shown, it is also readily conceivable to design it on both sides in order to enable cutting on both sides.

It follows from the above description of numerous possible exemplary embodiments of the invention that there is a wide range of variation which can be used to implement the invention in practice. In particular, further shapes for the cutting knives or the cutting edges are conceivable in order to adapt the invention to special applications, materials, channel shapes and the like. It also goes without saying that in some embodiments of the cutting knives, in particular in the serrated or corrugated straight cutting knives, a separate use with certain materials is also advantageous, even if surface channels do not have to be cut out in every case.

Claims (23)

Method for introducing surface channels (82) with an at least approximately rectangular cross-section into sheet material made of soft material, in particular mineral fiber insulation mats (80) or sheets made of a styrene polymer, in which a motor-driven cutting tool (10) with an oscillating cutting knife (20; 40 ; 90; 110; 110a; 140; 140a) is used, characterized in that a U-shaped cutting knife (20; 40; 90; 110; 110a; 140; 140a), the cutting edge (29; 64; 95; 119; 119a; 151; 151a) around the sections forming the U (24, 25, 26; 61, 62, 63; 92, 93, 94; 112, 113, 114; 112a, 113a, 114a; 144, 145, 146; 144a , 145a, 146a), is guided essentially in a straight line (83) through the plate material. Method for introducing surface channels (82) with an at least approximately rectangular cross-section into sheet material made of soft material, in particular mineral fiber insulation mats (80) or sheets made of a styrene polymer, in which a motorized cutting tool with an oscillating cutting knife (100) is used characterized in that, in a first step, an L-shaped cutting knife (100), the cutting edge (103) of which rotates around the sections (102, 104) forming the L, is guided essentially in a straight line through the plate material, and in a second step a Cutting knife (100) with a straight section (102) is guided parallel to the guidance of the first step through the plate material in such a way that a continuous strip of plate material can be removed from the plate material. A method according to claim 2, characterized in that for the introduction of wide surface channels, the first and the second step are carried out several times in succession, in parallel and side by side. Device for introducing surface channels (82) with an at least approximately rectangular cross section into sheet material made of soft material, in particular mineral fiber insulation mats (80) or sheets made of a styrene polymer, with a motor-driven cutting tool (10), in which a cutting knife (20; 40; 90; 110; 110a; 140; 140a) about an axis (14; 96; 118; 118a; 150; 150a) with an angular amplitude in the range between 0.5 ° and 7 ° and a frequency in the range of approximately 10,000 to 25,000 rpm is moved oscillating and the cutting knife (20; 40; 90; 110; 110a, 140, 140a) angled sections (21 - 27; 42, 43, 61 - 63; 92, 93, 94; 112-116 ; 112a-116a; 142-148; 142a-148a), which are at least partially provided with a cutting edge (29; 64; 93; 119, 119a, 151; 151a), characterized in that the cutting edge (29; 64; 95; 119; 119a; 151; 151a) over at least three sections (24 - 26; 61 - 63; 92, 93, 94; 112-114; 112a-114a; 144-146 ; 144a-146a) that form a U with each other. Apparatus according to claim 4, characterized in that at least one of the sections (24, 26; 61, 63; 114; 114a; 146; 146a) forming the free ends of the U has a further section (23, 27; 43; 115; 115a; 147; 147a). Apparatus according to claim 5, characterized in that the angled section (23, 27; 43) extends outwards, away from the clamping side. Apparatus according to claim 5, characterized in that the angled section (115, 115a; 147, 147a) is provided at the outer, free end of the U-forming section (114, 114a, 146, 146a), extends in the direction of the clamping side and is supported on one of the sections (112, 112a, 143, 143a) on the clamping side. Apparatus according to claim 7, characterized in that the angled section (115, 115a, 147, 147a) is welded to one of the sections (112, 112a, 143, 143a) on the clamping side. Device according to one of claims 4 to 8, characterized in that the cutting knife (40) comprises a blade holder (41) for inserting an exchangeable blade (60). Apparatus according to claim 9, characterized in that the blade (60) is U-shaped and can be locked with its free ends in slots (45, 46) in the blade holder (41). Apparatus according to claim 10, characterized in that a plurality of parallel slots (45a, 45b, 46a, 46b) are provided in the blade holder (41) for introducing channels (82) of different widths (B). Apparatus according to claim 10 or 11, characterized in that latching means are provided for introducing channels (82) of different depths, which allow the free ends to be locked in the slots (45, 46) at different heights. Device according to Claim 12, characterized in that the latching means are designed as tongues (51, 53) in the slots (45, 46) which engage in counter slots (70, 71) in the free ends. Device for introducing surface channels (82) with an at least approximately rectangular cross-section in sheet material made of soft material, in particular mineral fiber insulation mats (80) or sheets made of a styrene polymer, with a motor-driven cutting tool, in which a cutting knife (100) about an axis (105) is moved in an oscillating manner with an angular amplitude in the range between 0.5 ° and 7 ° and a frequency in the range of approximately 10,000 to 25,000 rpm and the cutting knife (100) has sections (102, 104) which are angled to one another and which have at least are partially provided with a cutting edge (103), characterized in that the cutting edge (103) runs over at least two sections (102, 104) which together form an L. Device according to claim 14, characterized in that, as an alternative to the L-shaped cutting knife (100), a non-angled cutting knife (100 ') can be inserted into the cutting tool. Device according to one or more of claims 4 to 15, characterized in that the cutting edge (95, 114a, 151a) is serrated. Device according to one or more of claims 4 to 16, characterized in that the cutting edge (103) is corrugated. Apparatus according to claim 16 or 17, characterized in that the cutting knife (90 ') on one side in one Cutting direction with a smooth cutting edge (95b ') and on the other side in the opposite cutting direction with a serrated or corrugated cutting edge (95b). Device according to one or more of claims 4 to 18, characterized in that the cutting edge (95) extends in an arc. Device according to claim 19, characterized in that the cutting edge (95) runs along a convex arc. Device according to one or more of claims 4 to 20, characterized in that at least one of the sections (102) provided with a cutting edge (103a) is tapered. Device according to one or more of claims 4 to 21, characterized in that the axis (105) extends at right angles to a first section (102) adjacent to a clamping section (101) of the cutting knife (100) and provided with the cutting edge (103) . Use of the device according to one or more of claims 4 to 22 for introducing surface channels (82) with at least approximately rectangular cross-section in sheet material made of soft material, in particular mineral fiber insulation mats (80) or sheets made of a styrene polymer.

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