METHOD AND APPARATUS FOR CREATING A FOLD LINE ON CORRUGATED SHEET TRANSVERSELY OF THE CORRUGATIONS

Abstract: The invention relates to a method and an apparatus for creating fold lines in corrugated sheet transversely of the corrugations for enabling in a subsequent step bending of the sheet to a desired angle. According to the method the sheet (4) is fixed between two locking means (5, 6) arranged on a die (2) in an edging press or similar and by means of a pressbar (1) a fold line in the form of indents in the crests of the corrugations is created.

Description: METHOD AND APPARATUS FOR CREATING A FOLD LINE ON CORRUGATED SHEET TRANSVERSELY OF THE CORRUGATIONS TECHNICAL FIELD The present invention relates to a method and apparatus for creating fold lines when bending corrugated sheet transversely of the corrugations. The invention is intended preferably for application in the building construction field for roofing purposes and in the construction of industrial buildings and storage locations, tool sheds, etc., in such cases as those where the walls of said building structures are also covered with corrugated sheet. The inventive method can also be used advantageously in other fields, for instance in the provision of corrugated sheet surrounds for loading pallets. BACKGROUND ART Since corrugated sheet cannot be bent transversely of its corrugations without great difficulty, it is endeavored to avoid such constructions, by placing joints at angled locations, where the sheets are placed at an angle to one an- other, and then covering the joints with an angled strip bent from flat sheet. Alternatively, one sheet can be allowed to project over the joint location, when possible. Consequently, there is a need to be able to bend corrugated sheet easily, for instance so that corrugated sheet can be placed over an arris or roof ridge, thereby eliminating the need for separate ridge plates. When constructing sheds or similar, simple storage facilities, an advantage would be gained if one and the same corrugated sheet could be extended from the roof of a building down onto a side wall thereof. In the Swedish patent 459481 an apparatus for creating a fold line transversely of the corrugations is shown which fold line in a later step will enable the bending of the sheet to a desired angle over e.g. the edge of a workbench. In the known apparatus the sheet is kept tightened against the die in an edging press or the like by means of a tongued pressfoot, whereby the tongues are brought into pressure engagement with the valley bottoms of the sheet, whereafter a bar forming part of the press or the device during its movement towards the die is caused to form a fold line in the form of recesses in the crest of the corrugations of the sheet. The object of the tongued pressfoot is to keep the sheet locked against the die preventing undesirable deformation of the sheet appearing as an increase in the dimensions of the sheet at the fold line. This apparatus requires in order to enable pressing of fold lines in sheets having different types of corrugations that the apparatus is provided with a number of pressfeet having different positions of the tongues, alternatively that the tongues are arranged adjustable on the pressfoot. Changing the pressfoot and adjusting the tongues of the pressfoot respectively is time consuming and requires in the latter case a certain ability by the operator. These apparatuses are preferably suited for stationary use as the force re- quired to keep the sheet pressed against the die often exceeds the force required to create the fold line. This leads to the necessity that a frame or the like comprised in the apparatus which carries the total press forces has to be given much larger dimensions than if it only had to carry the force required to press the fold line. When the apparatuses are designed to make fold lines in standard sizes of corrugated sheet they will be given such a weight that they will be difficult to handle when they have to be used at a working site. A further disadvantage with the portable apparatuses which are often hand operated is that the operator also has to create the force for tightening of the sheet against the die in addition to the force required to make the fold line. BRIEF DESCRIPTION OF THE INVENTION The object of the present invention is to eliminate said disadvantages by providing on one hand a method for simplifying the making of a fold line on a corrugated sheet transversely of its corrugations and on the other hand a more easy to handle and additionally less force requiring apparatus for carrying out the method. This is achieved by means of the method and the apparatus the characteristics of which appear from the following claims. DESCRIPTION OF THE DRAWINGS The invention will be described more in detail with reference to the enclosed drawing on which figure 1 shows the principal for making a fold line ' and the required apparatus in a side view, figure 2 shows figure 1 including further details, figure 3 shows a complete apparatus in a front view and figure 4 shows a plain view of the section A-A in figure 3. PREFERRED EMBODIMENT The principal according to the invention for making a fold line appears from figure 1. In a side view a die 2 included in an edging press is here shown on which a corrugated sheet 4 is placed. In order to make a fold line 3 in this sheet 4 a pressbar 1 also included in the edging press provided with a rounded edge is moved towards the die under great force, by means of hydraulic pistons or by suitable equivalent means. The fold line or weakening obtains the form of an indent 3 in the crests of the corrugations in the sheet 4. The depth of the indent can be varied and therewith adapted to the angle to which the sheet shall be bent in a second stage, by adjusting the length of stroke of the pressbar. In order to prevent that the sheet in the area of the indent expands sideways the sheet is firmly fixed between two locking members 5, 6. In figure 2 the sheet according to figure 1 is shown locked by means of such locking members of which only the member 5 is shown in the figure. The locking means extends on both sides of the fold line and at its central part a recess 7 is arranged in order to let the pressbar pass in its movement against the die. Figure 3 shows in a front view a complete apparatus including a frame 12 the lower bar of which is constituted by the die 2 and at the upper bar 13 of which hydraulic pistons 11 are arranged to press " by means of their piston- rods 14 the pressbar 1 against a sheet 4 positioned on the die which sheet is fixed between the locking means 5, 6. In figure 4 a section A-A through the apparatus according to figure 3 is shown in a plane view with the corrugated sheet 4 fixed on the die 2 between the locking members 5, 6. As is shown in figures 3 and 4 the locking means are provided with two planes perpendicular to each other one of which 8 is arranged vertically and is intended to bear against the side of the sheet and is provided with a recess 7 which al- lows the pressbar to pass in its movement. The locking means is in view of fixing the sheet intended to be displaced along the upper surface of the die whereby its second plane 9 bears against the die and could be locked against the die by means of screws 10. A sheet provided with one or several fold lines can be transported and handled as untreated sheet and be bent to a desired angle in the second stage with the aid of simple means over the edge of a workbench or some like support.

Claims: CLAIMS 1. Method for creating a fold line on a corrugated sheet transversely of the corrugations in order to enable in a subsequent step the bending of the sheet to a desired angle, characterised in that the corrugated sheet is placed on a flat die (2) or another flat support in an edging press or similar apparatus in which the sheet (4) is held in position by means of fixing the same between locking means (5, 6) arranged at the die (2) on each side of the sheet whereafter a pressbar (1) forming part of the edging press or the apparatus during its movement towards the die is caused to create a fold line in the form of indents (3) in the crest of the corrugations of the sheet (4). 2. Apparatus for pressing fold lines in corrugated sheet (4) transversely of the corrugations, characterized in that it comprises a flat die or similar (2), a movable pressbar (1) which is located in a plane perpendicular to the die (2) , means in the form of at least one hydraulic piston (11), screw, eccentric mechanism' or the like effective in moving the pressbar (1) towards and away from the die (2), locking means (5, 6) between which the sheet (4) is fixed against the die (2), the arrangement being such that in pressing a fold line in a sheet (4), the pressbar (1) is caused to carry out a reciprocating movement or a working stroke towards the die (2) and therewith press a fold line in the form of an indent in the crests of the sheet (4). 3. Apparatus according to claim 2, characterised in that at least one of the locking means (5, 6) is arranged adjustable at the die (2) to enable the fixing of sheets (4) having different widths.

Inventors: BAUMBACH THORKILD, BAUMBACH, THORKILD
Applicants: BAUMBACH THORKILD, BAUMBACH, THORKILD
Application year: 1998
Main classification: B21D11
IPC codes: B21D11, B21D13