GB1565687A - Cutting machine - Google Patents

Description

(54) CUTTING MACHINE (71) We, HELMUT MEYER AND PETER NEUGEBAUER, both citizens of the Federal Republic of Germany, of 2083 Halstenbek, Bahnhofstr. loe, Federal Republic of Germany, and 2 Norderstedt, Hans-Salb-Strasse 26, Federal Republic of Germany, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in any by the following statement: The invention relates to a machine for cutting surfaces with a rotary cutter holder with a cutting sector projecting from the base of the machine.

A known machine is used as a handoperated device and is particularly suitable for cutting recesses into a surface, a base surface of the machine being located in front of the blade holder and sliding on the area to be machined. A base portion located behind the blade holder is guided on the already machined surface, whereby it runs on a plane which differs by one step from a plane located in front of the cutterholder. This step generally corresponds to the portion of the cutter holder projecting from the base.

This machine can substantially work with a given depth of cut. In view of the predetermined step, different depths of cut cannot be set. Furthermore, in general, the supporting plate of the base surface located behind the cutter holder in the feed direction is guided relatively narrowly in the milled slot, so that divergences from the linear feed direction are either not possible or are only possible to a limited extent. However, in many cases, it is necessary to be able to adapt the depth of cut to particular requirements. In addition, and particularly when carrying out repair work, a feed direction is required which differs from the straight line in order to be able to cut, for example, annular surfaces to a given depth.

According to the invention there is provided a machine for cutting surfaces with a rotary cutter which has a cutting sector projecting from the base of the machine, wherein the base comprises a supporting plate comprising two side plates extending parallel to the direction of movement of the machine when cutting and disposed one beyond each of the two ends of the cutter holder to form the outer lateral parts of said supporting plate.

Along its complete supporting plate this machine is guided on the unmachined surface area, so that it is not cramped by the cut already made. It is possible in this way to be able to cut curves of random shapes in the unmachined surface. In addition, the depth of cut is not fixed, because with regard to the supporting plate, the cutter holder can be adjusted in such a way that it projects from the said plate by the amount which is most advantageous for the particular application.

Further details of the invention can be gathered from the following detailed description of a preferred embodiment and the accompanying drawings, in which: Fig. 1 is a perspective view of a machine according to the invention, Fig. 2 is a side view of the machine, Fig. 3 is a view from below the machine.

The machine substantially comprises a casing 1, a cutter holder 2 and a supporting plate 3. The cutter holder 2 is constructed as a cutter block with inter changeable cutters, whose shaft 4 is mounted in the casing. At right angles to the feed direction it runs in a plane which is parallel to the plane in which the machine feed takes place. Casing 1 together with supporting plate 3 rests on a surface 5 to be machined and from which a recess 6 is to be cut. This recess is in the form of a slot, whose width is equal to the width of the cutter holder 2.

The supporting plate 3 comprises three different partial plates (Fig. 3), whereof a central plate 7 is arranged in front of the cutter holder 2 in the direct feed direction, whilst the two side plates 8, 9 are located on either side of the recess 6 to be made, in the same plane as central plate 7.

The cutter holder is fixed in casing 1 on a height adjustment means 10, which is substantially constructed as two perpendicularly directed guide raiIs in which a slide 11 slides in a continuously adjustable vertical direction. Shaft 4 of the cutter holder 2 is mounted in said slide 11. A belt pulley 12, connected with a drive 14 via a driving belt 13 can be fixed at one end of the shaft 4 for the purpose of driving the cutter holder 2. Drive 14 is an electric motor which is fixed to the rear part 15 of the machine, when viewed in the feed direction.

Cutter holder 2 projects from the plane of supporting plate 3 by a lower section 16, the height of sector 16 corresponding to the depth of cut by which cutter holder 2 works into surface 5. This depth of cut can be changed when slide 11 is displaced and fixed in the direction of surface 5 or opposite thereto, within the height adjustment means 10. In addition, it is also possible to modify the plane of supporting plate 3 relative to the cutter holder 2. For this purpose, the side plates 8, 9 can be moved upwards or downwards relative to casing 1. The attachment of the side plates 8, 9 guides them along a chamfer on casing 1 in the direction of the upper edge 18 thereof and they are fixed to casing 1 with an adjustment means 19, which serves for the parallel displacement of chamfer 17 relative to the corresponding limitation of casing 1.Such means comprises a plate 20 fixed to the chamfer 17 and which has a bore 21 which co-operates with corresponding holes 22 in casing 1. Depending on the desired setting of side plates 8, 9, bore 21 is connected with one of the holes 22 by means of a corresponding pin.

Central plate 7 is provided with mounting supports 23, which can for example be provided at each of the four corners of a central plate 7 in a rectangular arrangement. The mounting supports 23 permit the fitting of spacer plates below the central plate 7 by means of locking devices which are not shown in detail. It is also possible to vary the shape and depth of recess 6 by means of these spacer plates. Thus, it is for example possible to fix the mounting supports 23 beneath central plate 7, a spacer plate in the form of a sloping plane. By means of this sloping plane, it is possible to guide the machine over surface 5 in such a way that on one side recess 6 is cut deeper into surface 5 and on the other is cut less deep into surface 5. In accordance with the sloping plane fixed beneath central plate 7, the two side plates 8, 9 must be fixed to the machine at differing heights.Mounting supports 23 can be in the form of holes in which are fixed corresponding toggles.

Cutter holder 2 can rotate both in a clockwise and in a counter-clockwise direction. If the machine is used for cutting a surface area 5, whose top surface is covered with a hard layer, for example of plastics, it is recommended that the cutter holder 2 be moved in a clockwise direction. In this rotation direction, the individual cutters 24 strike the hard layer of the surface 5 from below, so that the latter breaks before one of the cutters 24 strikes the hard layer. Thus, the cutters 24 only act on the soft layers located beneath the hard layer, so that they remain sharp for a longer period than would be the case if it were necessary to cut the hard layer. The profitability of the machine is increased due to the resulting longer service life.

A sighting mechanism 25 is provided on the upper edge 18 of casing 1 which enables the operator to see surface 5. As a result of this sighting mechanism, it is easier for the operator to guide the machine in a given direction of surface 5. A corresponding guide mark on surface 5 can be seen through the sighting mechanism 25, so that the machine can be guided along this mark.

A handle 29 is also located on upper edge which facilitates the guidance of the machine. The handle is appropriately connected with a switch which is used for switching on drive 14.

In order to produce a recess 6, the height of cutter holder 2 is adjusted by means of the height adjustment means in such a way that the sector 16 of cutter holder 2 projecting from supporting surface 3 corresponds to the desired depth of recess 6. In the case that recess 6 is to be made deeper on one longitudinal edge 27 than on the other longitudinal edge 28, a corresponding spacer is additionally fixed to central plate 7 and side plates 8, 9 are adjusted to a corresponding height with the aid of adjusting attachment 19. The machine can then be placed on any random point of the surface 5 to be machined. Following the switching on of drive 14, cutter holder 2 starts moving and works into the surface 5 until the entire supporting plate 3 rests on the unmachined surface 5. The machine can now be moved in the feed direction, whereby cutter holder 2 works into surface 5 in the manner desired by the operator.

In the case that a predetermined feed direction must be maintained, the operator can observe through the sighting mechanism 25 to ensure that the machine moves along a corresponding path. The steering of the machine presents no difficulties for the operator, because the guidance of the machine only takes place on the unmachined surface 5, so that the steering of the machine is not determined by the edges of an already produced recess.

By means of this machine, it is also possible to produce different profiles for the recess 6. To this end, the cutter holder 2 is arranged in accordance with this profile. If the recess 6 to be produced is deeper in its central area than at the edges, in the central area of cutter holder 2 cutters 24 can project further therefrom than at the ends of cutter holder 2.

With a view to guiding the machine on a supporting plate 3 which runs uniformly over its entire surface area on a plane which acts on surface 5, at the start of use the machine can be placed on a random point of surface 5.

Thus, the start of use is not dependent on it being in the area of one edge of the surface.

Cutter holder 2 still works into surface 5 when the machine is placed on a random point of said surface.

The cutting depth can also be adjusted by some means other than the above-indicated height adjustment means. It is, for example, possible to provide gratings which do not normally, however, permit a continuous adjustment of the depth of cut. The influencing of supporting plate 3 by adjusting side plates 8, 9 or fitting spacer plates on the central plate 7 can also be replaced by other possibilities of adjusting supporting plate 3 relative to cutter holder 2. In this connection, both side plates 8, 9 and central plate 7 may be attached to casing 1 via a continuous adjusting mechanism.

WHAT WE CLAIM IS: 1. A machine for cutting surfaces with a rotary cutter which has a cutting sector projecting from the base of the machine, wherein the base comprises a supporting plate comprising two side plates extending parallel to the direction of movement of the machine when cutting and disposed one beyond each of the two ends of the cutter holder to form the outer lateral parts of said supporting plate.

2. A machine according to claim 1, wherein the supporting plate includes an additional plate which extends in a direction substantially perpendicular to the direction of movement of the machine.

3. A machine according to claim 2, wherein the cutter holder projects beyond the supporting plate by the depth of cut.

4. A machine according to claim 3, wherein relative to the supporting plate, the depth of the cutter holder is adjustable.

5. A machine according to any of claims 1 to 4, wherein at least one spacer plate is attachable to the supporting plate for adjusting the depth of cut.

6. A machine according to any of claims 1 to 5, wherein the cutter holder is constructed as a block, whose surface is provided with cutters.

7. A machine according to any of claims 1 to 6, having interchangeable cutters.

8. A machine according to any of claims 1 to 7, having a sighting mechanism for observing a cutting path.

9. A machine according to claim 8, wherein the sighting mechanism is in the form of a slot which passes through the machine and whose centre is located above the cutting path.

10. A machine according to claim 2 wherein the side plates are independently adjustable in relation to a casing of the machine.

11. A machine according to claim 10, wherein each plate is provided with a lug which is pierced to receive a pin detachably engageable with any one of a row of holes in the machine casing for securing the plate thereto.

12. A machine for cutting surfaces constructed and arranged substantially as hereinbefore described and shown in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (12)

**WARNING** start of CLMS field may overlap end of DESC **. recess 6. To this end, the cutter holder 2 is arranged in accordance with this profile. If the recess 6 to be produced is deeper in its central area than at the edges, in the central area of cutter holder 2 cutters 24 can project further therefrom than at the ends of cutter holder 2. With a view to guiding the machine on a supporting plate 3 which runs uniformly over its entire surface area on a plane which acts on surface 5, at the start of use the machine can be placed on a random point of surface 5. Thus, the start of use is not dependent on it being in the area of one edge of the surface. Cutter holder 2 still works into surface 5 when the machine is placed on a random point of said surface. The cutting depth can also be adjusted by some means other than the above-indicated height adjustment means. It is, for example, possible to provide gratings which do not normally, however, permit a continuous adjustment of the depth of cut. The influencing of supporting plate 3 by adjusting side plates 8, 9 or fitting spacer plates on the central plate 7 can also be replaced by other possibilities of adjusting supporting plate 3 relative to cutter holder 2. In this connection, both side plates 8, 9 and central plate 7 may be attached to casing 1 via a continuous adjusting mechanism. WHAT WE CLAIM IS:

1. A machine for cutting surfaces with a rotary cutter which has a cutting sector projecting from the base of the machine, wherein the base comprises a supporting plate comprising two side plates extending parallel to the direction of movement of the machine when cutting and disposed one beyond each of the two ends of the cutter holder to form the outer lateral parts of said supporting plate.

2. A machine according to claim 1, wherein the supporting plate includes an additional plate which extends in a direction substantially perpendicular to the direction of movement of the machine.

3. A machine according to claim 2, wherein the cutter holder projects beyond the supporting plate by the depth of cut.

4. A machine according to claim 3, wherein relative to the supporting plate, the depth of the cutter holder is adjustable.

5. A machine according to any of claims 1 to 4, wherein at least one spacer plate is attachable to the supporting plate for adjusting the depth of cut.

6. A machine according to any of claims 1 to 5, wherein the cutter holder is constructed as a block, whose surface is provided with cutters.

7. A machine according to any of claims 1 to 6, having interchangeable cutters.

8. A machine according to any of claims 1 to 7, having a sighting mechanism for observing a cutting path.

9. A machine according to claim 8, wherein the sighting mechanism is in the form of a slot which passes through the machine and whose centre is located above the cutting path.

10. A machine according to claim 2 wherein the side plates are independently adjustable in relation to a casing of the machine.

11. A machine according to claim 10, wherein each plate is provided with a lug which is pierced to receive a pin detachably engageable with any one of a row of holes in the machine casing for securing the plate thereto.

12. A machine for cutting surfaces constructed and arranged substantially as hereinbefore described and shown in the accompanying drawings.