SHEET METAL CUTTING AND FORMING APPARATUS

Abstract: An apparatus for cutting and shaping sheet metal, having an input side (1) from where a metal sheet (2) is fed into the apparatus, and an output side (3) from where the cut and shaped metal sheet is received from the apparatus. The apparatus comprises a sheet metal cutting device (4) for cutting the metal sheet into two parts, a first part (5) and a second part (6), and a shaping device (7) for shaping the flanges (8) produced in the sheet as it is cut, said shaping device (7) being disposed after the cutting device (4), on its output side (3).

Description: Sheet metal cutting and forming apparatus The present invention relates to a sheet metal cutting and shaping apparatus as defined in the preamble of claim 1. In the treatment of sheet metal, various cutting and shaping apparatus are generally used in which the machining components may consist of e.g. discoid or bar-like machining tools. These apparatus have been designed to form grooves or patterns of desired shape in sheet metal by bending and stretching. The purpose of the shaping may be e.g. to stiffen the sheet or to produce a suitable shape for a joint between two parts made of sheet material. Especially thin sheets are used as insulation sheeting to protect insulating ma- terial against external stresses. For example, insulated pipes are provided with pre-machined sheet metal casings, which are manufactured as prefabricated parts of given lengths. These sheet metal tubes are provided with suitably shaped grooves needed for an overlapping joint to be made between tube ends. The grooves at the ends of the prefabricated tube are so shaped that the groove at one end has e.g. a concave shape designed to remain inside another tube while the groove at the other end has e.g. a convex shape designed to remain on the outside. In connection with the installation of piping, the sheet metal tubes have to be cut to lengths corresponding to the pipe sections to be insulated and a joint grooving has to be prepared in the region of the cut. The cutting is performed using e.g. a cutting wheel or some other tool applicable for cutting. The joint grooving is prepared using a tool designed for grooving. Normally, the waste piece left over remains unused. The object of the invention is to disclose a sheet metal cutting and shaping apparatus that allows simultaneous mechanical cutting and shaping of insulating casing sheets, especially casing sheet metal used to form a casing on pipes. The apparatus of the invention shapes the flanges created in conjunction with cutting and thus forms joint grooves on both pieces produced via the cutting operation. In this text, 'flange' refers to an area at the edge of a sheet, typically having a width of 1-15 cm from the edge . As for the features characteristic of the present invention, reference is made to the claims. The invention is based on an apparatus comprising a sheet metal cutting device and a sheet metal shaping device. The apparatus comprises an input side, from where the sheet metal is fed into the apparatus, and an output side, from where the cut and shaped sheet metal is received from the apparatus. The cutting and shaping devices are so disposed with respect to each other that, when a metal sheet is fed in at the input side, it will first encounter the cutting device, which cuts it, whereupon the flanges produced in cutting the sheet metal parts are passed to the shaping device, which shapes them in a desired manner. According to the invention, the shaping device is connected to the rest of the apparatus via a push-pull coupling, allowing the shaping device to be easily re- moved and attached to the apparatus, or to be replaced with another similar shaping device, thus making it easy to cut and shape different kinds of sheet metal and sheet metal tubes using an apparatus according to the invention. According to an embodiment of the invention, the shaping device comprises a pair of motorized wheels for each flange produced, said wheels being placed with their circumferences against each other, one of which wheels has a convex circumference while the other one has a concave circumference so that, when the flange of a part cut off from a metal sheet is passed between the wheels, it is shaped into a desired form. A cutting device according to an embodiment of the invention consists of a motorized plunger and a counterpart inside which the plunger partially fits, this plunger being disposed above that area of the metal sheet where a cut is to be made while the counterpart is correspondingly placed below the aforesaid area of the metal sheet. The plunger is so motorized that it moves in a reciprocating manner, knocking pieces off the metal sheet into the counterpart while the metal sheet is simultaneously advancing, a cut of a width corresponding to the plunger width being thus made in the metal sheet, which is thus cut into two parts. In the following, the invention will be described in detail by the aid of a few examples of its embodiments with reference to the attached drawings, which illustrate an embodiment of the apparatus of the invention. Fig. 1 represents an embodiment of the apparatus of the invention as seen from a direction transverse to the direction of advance of the metal sheet, Fig. 2 represents the shaping device of the apparatus illustrated in Fig. 1 as seen in the direction of advance of the metal sheet, Fig. 3 represents the cutting device of the apparatus illustrated in Fig. 1 as seen from the direction of advance of the metal sheet. In the embodiment of the apparatus illustrated in the drawings, the apparatus comprises a cutting device 4 and a shaping device 7, of which the cutting device 4 is disposed on the input side 1 while the shaping device 7 is placed on the output side 3 of the apparatus. The sheet metal 2 is supplied from the input side 1 of the apparatus, so it will encounter the cutting device 4, which makes in the metal sheet 2 a cut dividing the sheet into a first part 5 and a second part 6. After being thus divided into two parts, the metal sheet encounters the shaping device 7, which comprises a first wheel 9 and a second wheel 10, the flange 8 of the part being directed into the gap between these wheels. At least one of the wheels is motorized. The circumferences of the wheels have been so shaped that they will shape the flange 8 into the desired form. According to the present embodiment of the invention, a moving force is transmitted to the metal sheet 2 via the wheels 9 and/or 10 of the shaping device 7. According to the invention, the circumferences of the wheels may have e.g. a convex, concave, v-shaped or any other form, depending on the shape to be given to the flange 8. However, the circumference of one of the wheels has a form designed to fit the circumference of the other one, e.g. so that one of the wheels has a v-shaped circumference while the other one has a Λ-shaped circumference. The moving force can also be transmitted to the sheet 2 e.g. using power gears, or by any known method. According to an embodiment of the invention, the shaping device 7 is coupled to the rest of the apparatus by means of a push-pull coupling 12, making it possible to use shaping devices 7 of different types and sizes when sheet metal tubes 2 or sheets 2 of different types and sizes are to be cut and shaped. The push-pull coupling 12 may consist of any known push- pull coupling, e.g. a sleeve joint or a cotter joint. However, the push-pull coupling is of a design allowing the wheels of the shaping device 7 to be easily and quickly replaced with a wheel pair of a different type or size. According to an embodiment of the invention, the first wheel 9 and the second wheel 10 of the shaping device 7 differ from each other in respect of diametric size; according to another preferred embodiment of the invention, the first wheel 9 and the second wheel 10 of the shaping device 7 are adjusted to rotate at different speeds, so that when a straight sheet is being shaped, it will be possible, by varying the rotational speed or the size of the wheels, to form from the straight sheet 2 sheets and/or tubes having different curvatures. According to the invention, the shaping device 7 has a pair of wheels for each flange 8 produced as the sheet is being cut. In the embodiment of the invention illustrated in the drawings, the cutting device consists of a cylinder and a plunger with a cutter 11, the plunger being motorized and arranged to knock pieces off the moving metal sheet 2 against the cylinder and thus to produce in the metal sheet 2 a cut that divides it into two parts 5, 6. According to the invention, the cutting device 4 may be any known type of cutting device. For example, the cutting device 4 may consist of a cutting wheel, a circular cutter, an abrasive water jet device or a laser or flame cutting device. According to an embodiment of the invention, the cutting device 4 comprises a cutting wheel disposed between the first wheels 9 of the first and sec- ond wheel pairs, in which case the actual cutting takes place almost at the same point as the shaping. The apparatus of the invention may additionally comprise e.g. jigs serving to force the metal sheet 2 being shaped into a desired curvature. Accord- ing to the invention, the motorization of the cutting device 4 and shaping device 7 may be implemented in any manner; for example, the apparatus may only comprise a single motor, e.g. an electric motor, from which power is transmitted via a mechanical or hydrau- lie transmission to all devices needed. On the other hand, each device or part of the apparatus may be provided with a separate motor.

Claims: CLAIMS 1. Apparatus for cutting and shaping sheet metal, said apparatus having an input side (1) , from where a metal sheet (2) is fed into the apparatus, and an output side (3) , from where the cut and shaped metal sheet is received from the apparatus, characteri zed in that the apparatus comprises a sheet metal cutting device (4) for cutting the metal sheet into two parts, a first part (5) and a second part (6) , and a shaping device (7) for shaping the flanges (8) produced in the sheet as it is cut, said shaping device (7) being disposed after the cutting device (4) , on its output side (3) . 2. Sheet metal cutting and shaping apparatus as defined in claim 1, characteri zed in that the shaping device (7) is connected to the rest of the apparatus via a push-pull coupling. 3. Sheet metal cutting and shaping apparatus as defined in claim 1 or 2 , characteri zed in that the shaping device (7) comprises a pair of motorized wheels; a first wheel (9) and a second wheel (10) , said wheels being mounted with their circumferences against each other, and that the circumference of the first wheel is of a convex form while the cir- cumference of the second wheel has a corresponding concave form, and that the cutting device has been arranged to direct the flange (8) produced in the cutting operation into the gap between the wheels, and a corresponding pair of wheels for the flange (8) of the second part (6) . 4. Sheet metal cutting and shaping apparatus as defined in any one of claims 1 - 3, charac teri zed in that the rotational speeds of the first (9) and second (10) wheels of the shaping device (7) can be adjusted. 5. Sheet metal cutting and shaping apparatus as defined in any one of claims 1 - 4, charac - teri zed in that the cutting device (4) comprises one or more motorized cutters (11) arranged to cut out a strip from the sheet metal (2) between the first part (5) and the second part (6) .

Inventors: HYTTINEN MATTI KALEVI, HYTTINEN, MATTI, KALEVI
Applicants: HYTTINEN MATTI KALEVI, HYTTINEN, MATTI, KALEVI
Application year: 2001
Main classification: B21D35
IPC codes: B21D19, B23D27, B23D31