EP0215814A1

EP0215814A1 - Process for producing permanently curved pipe member sections for use in a slideway means

Info

Publication number: EP0215814A1
Application number: EP19860901148
Authority: EP
Inventors: Hans Husevag
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-02-18
Filing date: 1986-02-12
Publication date: 1987-04-01
Also published as: NO156676C; AU5397686A; NO850623L; WO1986004827A1; NO156676B

Abstract

Procédé de production d'une section de tube ayant un contour incurvé en permanence, à partir d'une section de tube droit divisé suivant la longueur, par exemple un tube de plastique extrudé. La section de tube ayant un pourtour incurvé peut être utilisée dans un toboggan ou autre agencement de guidage similaire. Dans la section de tube on effectue un fractionnement par segment de la section de tube sur une partie substantielle du contour arqué du tube dans le but de former une série de volets à bords parallèles (14, 15; 14a) et/ou des bandes (20) et, derrière, une ou plusieurs portions de tube arquées non fractionnées (13; 13a; 18, 19). La section de tube arquée est ensuite pliée autour de la (des) portion(s) de tube arquées non fractionnées (13; 13a; 18, 19) tandis que les volets de bord et les bandes se chevauchent les uns les autres respectivement. Finalement, les volets de bord et les bandes sont joints respectivement en étant reliés en permanence mutuellement pour former une section de tube rigide ayant un contour courbe spécifique.A method of producing a section of tubing having a permanently curved outline from a section of straight tubing divided along the length, for example an extruded plastic tubing. The tube section having a curved periphery can be used in a slide or other similar guide arrangement. In the tube section, a segmentation of the tube section is carried out over a substantial part of the arcuate contour of the tube in order to form a series of flaps with parallel edges (14, 15; 14a) and / or strips ( 20) and, behind, one or more portions of arcuate tube not divided (13; 13a; 18, 19). The arcuate tube section is then folded around the portion (s) of unfractionated arcuate tube (13; 13a; 18, 19) while the edge flaps and the bands overlap each other respectively. Finally, the edge flaps and the strips are joined respectively by being permanently connected to each other to form a rigid tube section having a specific curved outline.

Description

PROCESS FOR PRODUCING PERMANENTLY CURVED PIPE MEMBER SECTIONS FOR USE IN A SLIDEWAY MEANS.

This invention relates to a process for the production of permanently curved pipe member sections for use in a slideway means.

In hitherto known solutions for the production of members for a slideway or similar guide arrangement, it has been customary to fabricate the members by die casting when concerned with members of plastic material and by rolling, pressing and similar working when concerned with members of metal plate. In the production of complicated shapes such as arcuate pipe members having a curved contour in the vertical plane or in the horizontal plane or curved contours which curve partially in the vertical plane and partially in the horizontal plane, one has been dependent on complicated and expensive production tools. In addition, especially with members having low wall thicknesses, problems of deficient rigidity and strength are found in the portions of the members which have been specially stretched during the fashioning of the curved contour. With the present invention, the aim is a solution where the members can be fashioned in a relatively simple manner and with simple equipment into different curved contours of interest without thereby weakening particularly exposed portions of the arcuate pipe member.

Accordingly, the present invention resides in a process for producing a permanently curved pipe member section for use in a slideway or similar guide arrangement, characterised by segmentally splitting up a rectilinear and longitudinally divided pipe member section in a transverse direction and over a substantial portion of its arcuate contour from one or two opposite edge sides of the pipe member section and/or between edge portions in the central portion of the pipe member section to form a series of transverse edge flaps or strips and leave behind a pipe portion or a pair of opposite pipe portions unsplit in the transverse direction of between 5° and 45°, bending the resulting pipe member section in a longitudinal direction about the unsplit pipe portion or portions to establish a permanently curved contour while swinging together said edge flaps or strips one over the other into a gradually increasing, mutually overlapping engagement determined by the degree of curvature of said pipe member section, and fastening said edge flaps or strips into permanent engagement with each other.

By effecting, according to the invention, a splitting up of a longitudinally divided pipe section, segmentally in the transverse direction, on portions adapted for this along the arc of the pipe of the pipe member section and leaving behind other portions of the arc of the pipe unsplifup, there is the possibility of effecting a bending of the pipe member section around the unsplit pipe arc portion or portions while the split-up pipe arc portion or portions can be swung one over the other into a gradually overlapping engagement. By securing, thereafter, the overlapping arcuate pipe portions to each other in a permanent engagement, there is established, simultaneously, a specific curved contour of the pipe member section. In this way, there is achieved, at the same time, an extra bracing of the pipe member section by means of the mutually overlapping flap-like means, e.g., flaps or strips, without weakening the unsplit pipe portion(s).

In order to facilitate the swinging together of such edge flaps or strips into an overlapping or mutually displaced engagement, to get minimal deformation where there are only small displacements between the flaps and the strips,respectively,and to be able to allow the overlapping or mutually displaced portions to fit as tightly as possible to each other in the overlapped or mutually displaced condition, it is necessary that the splitting or saw tool which is employed be placed at a pointed angle on the wall of the pipe on splitting up so that the slot which is formed lies in a plane which crosses the wall and/or original axial direction of the pipe member section at an angle of between 15º and 45º, for example about 20º.

In order that the invention can be more clearly understood,convenient embodiments thereof will now be described, by way of example, with reference to the accompanying drawings in which:

Fig. 1 is a schematic view of a slideway constructed of permanently curved pipe member sections,

Fig. 2 is a cross-section of a divided pipe profile of a pipe member section according to a first embodiment, Fig. 3 is a scrap representation of a pipe member section having the pipe profile according to Fig. 2 and seen from above after a segmental splitting up of the pipe member section in the transverse direction has been effected,

Fig. 4 is a similar representation to Fig. 3 showing the pipemember section after bending to a specific curved contour,

Fig. 5 is a cross-section of walls of the pipe member section where split-up pipe portions are displaced relative to each other to a relatively small extent,

Fig. 6 is a cross-section of walls of the pipe member section where split-up pipe portions overlap each other to a relatively greater extent,

Fig. 7 is a cross-section of a divided pipe profile according to a second embodiment, Fig. 8 is a scrap section of a pipe member section with the pipe profile according to Fig. 7 shown in the bent condition,

Fig. 9 is a cross-section of a divided pipe profile according to a third embodiment, and

Fig. 10 is a scrap representation of a pipe member section with the pipe profile according to Fig. 9 shown in the bent condition.

Referring to Fig. 1, a slideway consists of a straight pipe member section 10a, a pipe member section 10b with successive convex and concave curve contours and a pipe member section 10c with a relatively gentle curve contour.

In Fig. 2, there is shown a pipe profile 10 which is made by the longitudinal division of a circular pipe of, for example, extruded synthetic plastics material. The pipe profile extends over an angular arc of about 225º. In Fig. 3, there is shown a, pipe member section with a pipe profile according to Fig. 2 and in Fig. 2 and 3 there is a segmental splitting up of the pipe member section from two opposite edges of the pipe member section having a first, short incision 11 and a second, elongate incision 12, there being left behind an unsplit intermediate arcuate pipe portion 13. The incision 11 extends over an arcuate angle of about 27º while the incision 12 extends over an arcuate angle of about 162 and the intermediate, unsplit arcuate pipe portion 13 extends over an arcuate angle of about 36°. In Fig. 4, the section is shown after it is bent about or around the arcuate pipe portion 13 with a convex outwardly directed curved contour at the unsplit arcuate pipe portion 13, that is to say the arcuate pipe portion 13 forms the outer curve of the curved contour, while the edge portion of the section, at the outer edge of the incision 12, forms the inner curve of the curved contour. The pipe member section in Fig. 4 is given a curved contour in the centre line plane of the arcuate pipe portion 13.

In Fig. 5, there are shown overlapping arcuate pipe portions, for example, at the middle of the incision 11 and in Fig. 6 there are shown overlapping arcuate pipe portions, for example, at the middle of the incision 12. In both instances, the incisions have been effected along the plane which crosses the longitudinal axis of the pipe member section according to Fig. 2 at an angle of about 20º. There are obtained thereby, along the incisions, obliquely bevelled edge portions which are strongly pointed so that the edge flaps 14 which form between the incisions 11 and the edge flaps 15 which form between the incisions 12 can be readily displaced relative to each other and fit relatively tightly to each other during bending of the pipe member section from the position shown in Fig. 3 to the position shown in Fig. 4. There is achieved, besides, the pointing of all pointed edges along the incisions in the same direction internally in the pipe member section. This is very important when the pipe member section is to be employed, for example, in a slide track, the section then being mounted so that the internally pointed edges point in the fall direction of the slide track or the direction of slide. Finally, the edge flaps 14 and 15 are welded together or jointed together in another suitable way via a joint connection as shown at 16. The joint connection is preferably designed so that there is formed a uniform transition from flap to flap. It will be observed that the bent pipe member section where it is exposed to particularly large loading, for example, in a slide track, is normally formed by the outer curve of the curved contour, that is to say the unsplit arcuate pipe portion 13 of the pipe section. In this unsplit portion 13, the pipe member section extends without joints and without irregularities. In Fig. 7, there is shown a pipe profile 10a which extends over an arcuate angle of about 180°. In this instance, there are designed two corresponding incisions 11a and 12a from each respective edge of the pipe member section and each over an arcuate angle a and b of about 75°, while there is left behind an unsplit arcuate pipe portion 13a along the bottom or the middle of the pipe profile with an arcuate angle c of about 30 .

In Fig. 8, there is shown a pipe member section with the pipe profile according to Fig. 7 after the pipe member section is bent about or around in the vertical plane with a convex downwardly directed curved contour at the unsplit portion 13a. There are illustrated mutually overlapping edge flaps 14a.

In Fig. 9, there is shown a pipe profile 10b which extends over an arcuate angle of about 180°. In this instance, there is designed an incision 17 in the bottom portion or middle portion of the pipe member section over an arcuate angle c of about 170°, while there are left behind, at two opposite edge portions of the pipe member section, an unsplit arcuate pipe portion 18 and 19 respectively, each with an arcuate angle a and b of about 5°. Between the incisions 17 there are formed, as shown in Fig. 10, corresponding strips 20 which mutually overlap each other in a manner which corresponds substantially to the edge flaps as shown in Figs. 4 and 8. In the embodiment in Fig. 10, the pipe member section is bent in the vertical plane with a convex upwardly directed curved contour.

According to the invention it is possible, from one and the same starting material, that is to say a pipe made of, for example, extruded synthetic plastics mate- rial and having a pipe profile of uniform wall thickness, to ensure a bending of the pipe member section in a specific plane by a relatively simple longitudinal division into said pipe member section of desired arcuate pipe profile and by simple segmental splitting up, in the transvere direction, into arcuate pipe regions suitable for this purpose. The said planes can, as desired, extend vertically or horizontally or, if desired, more or less obliquely in the vertical plane and the horizontal plane all according to the disposition of the incisions in the arc of the pipe. The effected incisions can be placed more tightly or further from each other than illustrated in the examples of the accompanying drawings in order to obtain a narrower or less narrow curved contour as required. In cases where the mutually overlapping flaps or strips form undesirably great irregularities internally in the bent pipe member section, it is also appropriate to effect planing of the edge portions in order to reduce the irregularities. Unsplit arcuate pipe portions are kept at from 5° to 45º so that there is obtained a bending of the pipe member section with minimal deformation of the unsplit portions.

Claims

1. Process for producing a permanently curved pipe member section for use in a slideway or similar guide arrangement, characterised by segmentally splitting up a rectilinear and longitudinally divided pipe member section in a transverse direction and over a substantial portion of its arcuate contour from one or two opposite edge sides of the pipe member section and/or between edge portions in the central portion of the pipe member section to form a series of transverse edge flaps (14, 15; 14a) or strips (20) and leave behind a pipe portion or a pair of opposite pipe portions (13; 13a; 18, 19) unsplit in the transverse direction of between 5º and 45º, bending the resulting pipe member section in a longitudinal direction about the unsplit pipe portion or portions to establish a permanently curved contour while swinging together said edge flaps (14, 15; 14a) or strips (20) one over the other into a gradually increasing, mutually overlapping engagement determined by the degree of curvature of said pipe member section, and fastening said edge flaps or strips into permanent engagement with each other.

2. Process according to claim 1, characterised in that the transverse splitting up is effected along a plane which crosses at an angle of between 15° and 45° the wall and/or the original axial direction of the pipe member section.