WO2019103672A1

WO2019103672A1 - Device for a pipe bending tool

Info

Publication number: WO2019103672A1
Application number: PCT/SE2018/000033
Authority: WO
Inventors: Janos Keller
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-11-23
Filing date: 2018-11-23
Publication date: 2019-05-31
Anticipated expiration: 2020-05-23
Also published as: SE1700288A1; EP3713689A4; SE541489C2; EP3713689A1

Abstract

The present invention relates to a tube bending tool (1) comprising support surfaces (2, 2', 2''), between which a tube (3) which shall be bent, is placed for bearing on and pressing against portions of the mantle surface (4, 4') of the tube (3) in providing a bend (5), said tube bending tool (1) has a pressure exerting unit (6) comprising at least one extension (8) displaceable forwards against the tube (3), where a convex bend bearing surface in the form of a shablon (10) is provided to press against the mantle surface of the tube (3). The front portion (9) has two elongated elements (12, 12'), which are cross-laid and provided flexible in their first ends (13, 13') in order to during bending press in a direction against the bending radius center, whereby different radius of the bend (5) on selected places can be done and just before a wanted bending angle has been reached a tension belt (25) fixed in two coupling links (26, 26'), so that this is can be tensioned against the side of the bent tube (3) and makes it possible that a distance between the supporting elements (15, 15') on existing supporting axis (18, 18') is decreased, which means that a spring back in the bent tube (3) disappears so that the same is loosen from the bending tool (1).

Description

DEVICE FOR A PIPE BENDING TOOL

The present invention refers to a tool intended to be used for bending tubes when a user bends the tube in situ where the tube shall be mounted and where it can be seen where it shall be bent, how much and by which radius.

On the marked existing structures of this type are today using big tube-bending machines, which are placed on working tables. The tubes must in this case after that one has taken necessary measures on the actual mounting place be bent according to those. Then it can be necessary with several rounds with the tube in hand away to that place, where it shall be mounted and back to the not movable tube-bending machine on the working table in order to be bent. These rounds must be taken also for small adjustment on the tube, when the same only nearly suits after many previous rounds. It takes a long time and it also happens that it will be a lot of wrong curvatures, which makes that the tube must be thrown away or can start to leak after some time. This costs much money.

One object of the present invention is to eliminate these drawbacks, which exist when using the not movable tube-bending machines mentioned above.

Thanks to the invention a device has now been provided for a tube-bending machine, which in an excellent way fulfills its purposes at the same time as the bending of the tubes can be done very quickly and that it is very easy to manufacture the bending of the tubes. The invention will be described closer below by aid of a preferred embodiment example with reference to the drawings enclosed, in which

Fig. 1 illustrates a schematic view from above of a tube-bending tool according to the present invention in a starting position for bending tubes,

Fig. 2 illustrates a tube-bending tool according to fig. 1 in a position where the bending itself has been started and where it can be seen how a limiting link works in those cases a tube shall be bent in an angle over about 90°,

Fig. 3 illustrates how a tensioning-belt is mounted in the

bending-tool before a desired bending has been reached and which unloads the bending-tool from the spring back tensions from the tube, and

Fig. 4 illustrates a position during the bending when 180° has been reached.

As can be seen from fig. 1 here is illustrated a tube-bending tool 1, which comprises support surfaces 2, 2', 2'' between which a tube 3 can be placed for bending and providing of a bend 5. The tube-bending tool 1 comprises preliminary a pressure exerting unit 6, which is provided with an extension 8, which can be pressured outwards from the same and which is provided in the front portion 9 of the pressure exerting unit 6, which is directed towards the tube 3, where a convexly bent bearing surface or shablon 10 is provided in the end 11 of the extension 8 and which by aid of a supplied force from the pressure exerting unit 6 via a direction forwards moveable extension 8 presses against a mantle surface 4 of the tube 3. The front portion 9 of the pressure exerting unit 6 have two elongated elements 12,12^', the first ends of which 13,13^' is linkably provided around bolts 17,17^' in the pressure exerting unit 6 and the other ends 14,14' of which shows that the tube 3 having support elements 15,15' displaceable along the mantle surface 4, in which the ends 14,14^' are linkably provided around bolts 18, 18^'. The support elements 15,15' are situated on each side of the shablon 10 before the bending in order to press the supported force in a direction towards the opposite mantle surface 4^' of the tube 3. When the shablon 10 is pressed more and more in a direction towards the inner mantle surface 4 the tube 3 is bended in a desired extent towards the support elements 15,15^', so that the bend 5 of the tube 3 reaches a bent angle up to at least about 90°. The pressure exerting unit 6 comprises a pneumatic controlled cylinder containing oil or gas. The elongated elements 12,12^' are cross laid so that during the bending press in a direction, which is directed mainly towards the center of the bending radius of the tube 3, so that different radius of the bending in determined places can be provided also on a position where the tube 3 shall be mounted.

The tube bending-tool 1 comprises a detachable limiting link 19, which limits the distance between the fastening axes 18,18^' of the two support elements 15,15', in which these support elements 15,15^' are suspended, said limiting link 19 can be folded together by aid of a joint 16 in the middle via a screw 20 having a nut 20'. In this way the limiting link now can be folded together, so that those two openings 23,23', which are present in each end 22 22^' will be right in front of each other when the limiting link 19 is folded together. In the beginning of the bending process the link is applicated in a folded together position over one of the fastening axes 18,18^' of the support elements 15,15^' through the two openings 23,23^' in the limiting link 19, which are situated outside each other at the same time as the other end 22^' is supported in, towards the periphery of the other fastening axis 18^' and in the same way is done on the other side of the support elements 15,15^' having a further portion link 21 for forming of a distance between the two support elements 15,15^', so that the start of the bending procedure of the tube 3 requires less force. Then after that the shablone 10 is pressed inwards towards the tube 3 the two portion links 21,21^' loosen when the distance between the two portion links 21, 21^' when the distance between the fastening axes 18,18^' is increasing. When the two portion links 21,21^' have been loosened they are applicated again but this time in an extended position having the two openings 23,23^' in each end 22,22^' over and above the two fastening axes 18,18', in which the support elements 15,15^' are fastened to and thereafter one continues to press the shablon 10 towards the tube 3. Just before one has reached the desired bending angle a stretching belt 25 is applicated into two coupling links 26,26' and these are thread over the head of the two screws 20, which constitute the joint 16 between the portion links 21,21' of the limiting link 19, whereupon the stretching belt 25 is tensioned against the side of the bended tube 3, whereupon the same pulls with it the fastening axes 18,18' in the middle of the limiting link 19 and make so that the distance between the fastening axes 18 18' of the support elements 15,15' decreases, which results in on one side that the return spring in the bent tube 3 disappears so that the same can be loosened from the tube bending tool 1 without tensions and on the other side that the links 26,26' 26^' having a fixed stretching belt 25 also have the possibility to bend in the tube 3 over 180° behind the shablon 10. This shablon 10 has an integrated form in the front edge, which extends along the tube 3 on both sides having the same length as the diameter as that of the tube 3, so that the formation of the shablon 10 is such that the form in the same follows the same diameter as that of the tube 3, except that it extends upwards to about 1 millimeter over half of the diameter and having continued formation of the radius on both over and underside of the shablon 10 and that means that the measure will be about 0,1 mm less than the diameter of the tube 3, which is pressed into the shablon 10 during the start of the bending. The result of this gripping function will be that during bending of the tube 3, the same wants to leave the shablon 10 but is pressed back in to the shablon 10 owing to that the tube 3 tends to grow in height, which makes that there is no room for the tube 3 to leave the shablon 10, which minimizes the deformations.

Claims

1. A tube bending tool comprising support surfaces (2, 2^', 2'^'), between which a tube (3) , which shall be bent, is placed for bearing on and pressing against portions of a mantle surface (4, 4^') of the tube (3) in providing a bend (5) of a tube (3), said tube bending tool (1) has a pressure exerting unit (6) comprising at least one extension (8) displaceable forwards in its front portion (9), which is directed towards the tube (3), where a convex bent bearing surface in the form of a shablon (10) is provided in the end (11) of the extension (8) in order to press against the mantle surface (4) of the tube (3) when said extension (8) delivers a force from the pressure exerting unit (6), said front portion (9) comprises two elongated elements (12,12^'), which are linkable in their first ends (13,13'), the opposite ends (14,14') of said elements (12,12^') comprising displaceable and movable provided support elements (15,15^') on each side of the shablon (10), which is pressed by the supplied force against the opposite or outer mantle surface (4^') of the tube (3) when the shablon (10) presses against an inner mantle surface (4) of the tube (3), so that the tube (3) is bent in a desired extent both between and against the support elements (15,15^'), and the two elongated elements (12,12') are in their first ends (13,13^') cross laid in order to during the bending press in a direction, which is directed mainly against the center of the bending radius of the tube (3) at the same time as different radius of the bend (5) can be provided on determined places, characterized by that the tube bending tool (1) comprises a limiting link (19), which limits the distance between the fastening axes (18,18^') of the support elements (15, 15^'), in which these support elements (15,15^') are fastened, and said limiting link (19) is foldable together by aid of a link (16) in the middle via a screw (20) having a nut (20^'), so that the openings (23,23^'), which are situated in each end (22,22') will be in the middle of each other, when the limiting link (19) is folded together, so that in the beginning of the bending process the same is intended that in a folded together position be placed over one of the fastening axes (18,18^') of the support elements (15,15^') by aid of the two openings (23,23^') in said limiting link (19) situated just outside of each other at the same time as the other link (22^') is leaned against the periphery of the other fastening axis (18'), whereupon the same procedure occurs on the other side of the support elements (15, 15^') having a further portion link (21) for constituting a distance between the two support elements (15,15^'), so that the start of the bending of the tube (3) requires less force when the shablon (10) is pressed in towards the tube (3) and the two portion links (21,21^') are loosened when the distance between the fastening axes (18,18^') increases and when the two fastening axes (18,18^') have been loosened they are again applicated but in a position having the two openings (23,23^') elongated in each ens (22,22^') over the two fastening axes (18,18^'), in which the support elements (15,15^') are fastened into, and thereafter a pressing of the shablon (10) continues against the tube (3) and just before a desired bending angle has been reached a stretching belt (25) is applicated into two coupling links (26, 26^') and these are in turn thread over the heads (27,27') of that screw (20) with nut (20'), which constitutes the lid (16) between the portion links (21,21^') and thereafter the stretching belt (25) can be extended against the side of the tube (3), whereupon the same draws with itself said fastening axes (18, 18^') in the center of the limiting links (19) and makes so that the distance between the fastening axes (18,18') of the support elements (15,15') reduces and this results partly in that a spring back in the bent tube (3) disappears, so that the same will be loosened from the tube bending tool (1) without tensions at the same time said stretching belt (25) having the links (26, 26') also gives the possibility to bend in the tube (3) over 180° behind the shablon (10).

2. A device according to claim 1, characterized in that the shablon (10) has an integrated form in the front, which extends along the tube (3) on both sides having the same length as the diameter of the tube (3), so that the formation of the shablon (10) is such that the form in the same follows the same diameter as the one of the tube (3) without that it extends up to about 1 mm over the half diameter and having the same form of the radius of both the over- and underside of the shablon (10) , which makes that the measure will be about 0,1 mm less than the diameter of the tube 3, which can be pressed into the shablon (10) during the start of the bending, which gives a gripping function which during bending of the tube (3) makes so that the same will leave the shablon (10) but is pressed back into the shablon (10) thanks to that it does not exist place for the tube (3) to leave the shablon (10), which minimize deformations.