Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
DEVICE FOR BENDING PIPES
Document Type and Number:
WIPO Patent Application WO/2016/144168
Kind Code:
A1
Abstract:
The invention relates to a device for bending a pipe with an outer diameter, comprising: -a first lever with first pivot members; -a second lever with second pivot members, wherein the second pivot members are engageable with the first pivot members of the first lever to pivot the first lever relative to the second lever about a pivot axis; -a groove element with a bending groove arranged on the first lever to engage with the pipe at a first side thereof, said bending groove being formed in an arc around the pivot axis with a radius corresponding to the desired bend and a cross section with a radius corresponding to the outer diameter; -a bending element arranged on the second lever for movement along the bending groove to engage with the pipe at a second side thereof in order to bend the pipe, wherein the second side of the pipe is opposite the first side of the pipe; -a retainer arranged on the first lever for retaining the pipe in a retaining position during bending, wherein the retainer is arranged at a distance of and in alignment with the bending groove; wherein the groove element comprises a groove extension extending from the bending groove towards the retainer, said groove extension curving in the same direction as the arc of the bending groove, and wherein the retainer and the groove extension are configured to allow disengagement of the pipe from the retaining position by movement of the pipe in a plane defined by the arc of the bending groove.

Inventors:
HOGERWERF PIETER ARIE (NL)
Application Number:
PCT/NL2016/050158
Publication Date:
September 15, 2016
Filing Date:
March 08, 2016
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
HOGERWERF PIETER ARIE (NL)
International Classes:
B21D7/06; B29C53/08
Domestic Patent References:
WO2008051162A12008-05-02
Foreign References:
DE2139552A11972-05-10
EP0014461A11980-08-20
US6463780B12002-10-15
NL2001715C22009-12-24
NL2001715C22009-12-24
Attorney, Agent or Firm:
RIEMENS, R.H. (2280 GE Rijswijk, NL)
Download PDF:
Claims:
C L A I M S

A device for bending a pipe with an outer diameter, comprising:

a first lever with first pivot members;

a second lever with second pivot members, wherein the second pivot members are engageable with the first pivot members of the first lever to pivot the first lever relative to the second lever about a pivot axis;

a groove element with a bending groove arranged on the first lever to engage with the pipe at a first side thereof, said bending groove being formed in an arc around the pivot axis with a radius corresponding to the desired bend and a cross section with a radius corresponding to the outer diameter;

a bending element arranged on the second lever for movement along the bending groove to engage with the pipe at a second side thereof in order to bend the pipe, wherein the second side of the pipe is opposite the first side of the pipe; a retainer arranged on the first lever for retaining the pipe in a retaining position during bending, wherein the retainer is arranged at a distance of and in alignment with the bending groove,

characterized in that

the groove element comprises a groove extension extending from the bending groove towards the retainer, said groove extension curving in the same direction as the arc of the bending groove,

and in that

the retainer and the groove extension are configured to allow disengagement of the pipe from the retaining position by movement of the pipe in a plane defined by the arc of the bending groove.

The device according to claim 1 , wherein the groove extension comprises a groove bottom and a groove sidewall extending from the groove bottom, and wherein a length of the groove extension is larger at the groove bottom than at the groove sidewall.

The device according to claim 2, wherein a length of the groove extension is maximal at the groove bottom and gradually decreases towards a free end of the groove sidewall.

The device according to claim 1 , wherein the groove extension has a cross section with a radius corresponding to the outer diameter of the pipe.

The device according to claim 1 , wherein a radius of curvature of the groove

extension is equal to the radius of the arc of the bending groove. The device according to claim 1 , wherein the groove extension terminates at the retainer side thereof with rounded edges.

The device according to claim 1 , wherein the retainer is indirectly arranged on the first lever by arranging the retainer on the bending element.

Description:
Title: Device for bending pipes The invention relates to a device for bending a pipe.

Such a device is for instance known from Dutch Patent publication NL2001715 also of the applicant. In this document a device for bending pipe with an outer diameter is disclosed, comprising:

- a first lever with first pivot members;

- a second lever with second pivot members, wherein the second pivot members are engageable with the first pivot members of the first lever to pivot the first lever relative to the second lever about a pivot axis;

- a groove element with a bending groove arranged on the first lever to engage with the pipe at a first side thereof, said bending groove being formed in an arc around the pivot axis with a radius corresponding to the desired bend and a cross section with a radius corresponding to the outer diameter;

- a bending element arranged on the second lever for movement along the bending groove to engage with the pipe at a second side thereof in order to bend the pipe, wherein the second side of the pipe is opposite the first side of the pipe;

- a retainer arranged on the first lever for retaining the pipe in a retaining position during bending, wherein the retainer is arranged at a distance of and in alignment with the bending groove. During use of the mentioned prior art device, the inventors noticed that many pipes were damaged after bending. Damage occurred in the form of a deformation of the pipe and/or in the form of scratches on the pipe. The amount of damage seems to depend amongst others on the type of material of the pipes and the bending stiffness of the pipes. It seems that the larger the bending stiffness, the more damage is caused, probably because the forces required for bending the pipe are much larger in that case.

It is therefore an object of the invention to provide a device for bending a pipe with an outer diameter which causes less damage to the pipes as a result of the bending operation. This object of the invention is achieved by providing a device for bending a pipe with an outer diameter, comprising:

- a first lever with first pivot members; - a second lever with second pivot members, wherein the second pivot members are engageable with the first pivot members of the first lever to pivot the first lever relative to the second lever about a pivot axis;

- a groove element with a bending groove arranged on the first lever to engage with the pipe at a first side thereof, said bending groove being formed in an arc around the pivot axis with a radius corresponding to the desired bend and a cross section with a radius corresponding to the outer diameter;

- a bending element arranged on the second lever for movement along the bending groove to engage with the pipe at a second side thereof in order to bend the pipe, wherein the second side of the pipe is opposite the first side of the pipe; and

- a retainer arranged on the first lever for retaining the pipe in a retaining position during bending, wherein the retainer is arranged at a distance of and in alignment with the bending groove,

wherein the groove element comprises a groove extension extending from the bending groove towards the retainer, said groove extension curving in the same direction as the arc of the bending groove, and wherein the retainer and the groove extension are configured to allow disengagement of the pipe from the retaining position by movement of the pipe in a plane defined by the arc of the bending groove. An advantage of the groove extension and the possibility for the pipe to disengage from (and thus also to engage with) the retainer by movement in the plane defined by the arc of the bending groove is that the risk of damage to the pipe is smaller, because the pipe can simply unroll from the bending groove onto the groove extension without passing sharp edges or experiencing undesired loads.

In an embodiment, the groove extension comprises a groove bottom and a groove sidewall extending from the groove bottom, and wherein a length of the groove extension is larger at the groove bottom than at the groove sidewall. Preferably, a length of the groove extension is maximal at the groove bottom and gradually decreases towards a free end of the groove sidewall.

This has the advantage that the pipe can be supported by the groove bottom of the groove extension, but at the same time there is enough space to insert and remove the pipe from the device.

In an embodiment, the groove extension has a cross section with a radius corresponding to the outer diameter of the pipe. Preferably, a radius of curvature of the groove extension is equal to the radius of the arc of the bending groove. In that case, the groove extension is a real extension of the bending groove.

In an embodiment, the groove extension terminates at the retainer side thereof with rounded edges to further reduce the risk of damages.

In an embodiment, the retainer is indirectly arranged on the first lever by arranging the retainer on the bending element. In an embodiment, the groove element is rotatable about the pivot axis, wherein the device comprises locking means to lock the groove element in at least two distinct angular orientations of the groove element relative to the first lever. The locking means may comprise a locking member arranged on the first lever that is engageable with at least two recesses in the groove element to lock the angular orientation of the groove element relative to the first lever.

In an embodiment, the first lever comprises a fork element with two parallel arms, wherein the groove element is arranged in between the two parallel arms of the first lever, wherein two cylindrical protrusions extend outwards from the arms of the first lever to form the pivot axis, and wherein the second lever comprises a fork element with two parallel arms, wherein the arms of the fork element of the second lever comprise a groove to engage with the protrusions on the arms of the fork element of the first lever for pivotal movement, and wherein the bending element is arranged in between the arms of the fork element of the second lever. Preferably, the cylindrical protrusions are formed by a single axis extending through the fork element, wherein the groove element comprises a through hole to engage with the single axis for rotational movements.

The invention will now be described in a non-limiting way by reference to the accompanying drawings in which like parts are indicated by like reference symbols, and in which:

Figure 1 : depicts a side view of a device for bending a pipe according to an

embodiment of the invention;

Figure 2: depicts a top view of the device of Fig. 1 ;

Figure 3: depicts a cross sectional view of the device of Fig. 2 along line A-A';

Figure 4: depicts a perspective view of the device of Fig. 1 ;

Figure 5: depicts a perspective view of the groove element of the device of Fig. 1 ; Figure 6: depicts a bottom view of the groove element of Fig. 5; and

Figure 7: depicts a side view of the groove element of Fig. 5. Figures 1-4 depict a device 1 for bending a pipe 2 according to an embodiment of the invention. The pipe 2 is only shown in some figures for clarity reasons. The device 1 comprise a first lever 3 and a second lever 5. The first lever 3 is provided with first pivot members 7 and the second lever 5 is provided with second pivot member 9. The first and second pivot members 7, 9 are engageable with each other as shown in Figs. 1-4 to pivot the first lever 3 relative to the second lever 5 about a pivot axis 1 1.

Arranged on the first lever 3 is a groove element 13 with a bending groove 15. The bending groove 15 is formed in an arc around the pivot axis 1 1 with a radius R1 corresponding to the desired bend and a cross section with radius R2 corresponding to an outer diameter D of the pipe 2.

Arranged on the second lever 5 is a bending element 17 for movement along the bending groove 15 by pivoting the second lever 5. In this embodiment, the bending element is a roller, which can rotate about rotation axis 19 to minimize friction between the bending element 17 and the pipe 2. In this embodiment, the roller comprises a groove 17a formed in a circle around the rotation axis 19 with a radius R3 and a cross section with radius R2 corresponding to an outer diameter D of the pipe 2.

The bending element 17 and the groove element 13 cooperate in bending the pipe 2. The bending groove 15 of groove element 13 engages with a first side 2a of the pipe 2. The bending element 17 engages with a second side 2b of the pipe 2, which second side 2b is opposite the first side 2a of the pipe 2. By moving the bending element 17 along the bending groove 15, the pipe 2 is bend.

However, bending a pipe requires engagement at two different positions along the length of the pipe. The bending element 17 and groove element 13 engage at one position. The other position is formed by a retainer 21 arranged indirectly on the first lever by being arranged on the groove element 13. The retainer 21 is configured to retain the pipe 2 in a retaining position during bending, wherein the retainer is arranged at a distance L of and in alignment with the bending groove 15, which alignment can for instance be seen in Fig. 2.

In the embodiment of Figs. 1-4, the groove element 13 is rotatable relative to the first lever 3 about pivot axis 1 1 allowing to make bends of up to 180 degrees in the pipe 2. The direction of this rotation of the groove element 13 is depicted in Fig. 1 by arrow 22. The groove element 13 in this particular embodiment is rotatable between a first position associated with a 90 degrees bend and a second position associated with a 180 degrees bend. In Figs. 1-4, the groove element 13 is shown in the second position.

The groove element 13 can be locked in the first position using a locking member 23 arranged on the first lever 3 that is moveable between a retracted position allowing the groove element to rotate about the pivot axis 1 1 and a locking position in which the locking member 23 engages with a recess 25 for locking the groove element in the second position or engages with a recess 27 for locking the groove element in the first position. Although not shown in the Figs., the locking member may be spring loaded urging the locking member to the locking position, such that the locking member has to be moved manually or by means of an actuator to the retracted position to rotate the groove element to another angular orientation. Spring loading the locking member has the advantage that releasing the locking member automatically urges the locking member to the locking position, so that no separate operation is required to achieve this.

Figs. 5-7 depict the groove element 13 of the device 1 of Figs. 1-4 in more detail. In Fig. 7, a groove bottom of the bending groove 15 is partially depicted using dashed line 15a. An end of the bending groove 15 is depicted using dashed line 15b. The bending groove 15 can alternatively be described as the part of the groove element 13 making full contact with the pipe 2 during bending. Hence, when the pipe 2 is retained by the retainer 21 , the groove bottom 15a makes first contact with the pipe 2 at point 15c.

The groove element 13 further comprises a groove extension 29 extending from the bending groove 15 towards the retainer 21. The groove extension 29 curves in the same direction as the arc of the bending groove 15.

The retainer 21 and groove extension 29 are further configured to allow disengagement of the pipe 2 from the retaining position by movement of the pipe 2 in a plane defined by the arc of the bending groove 13. This is illustrated in Fig. 6 by showing a cross section of the pipe 2 in solid lines to indicate the position of the pipe 2 in the retaining position, and by showing the same cross section of the pipe 2 in dashed lines to indicate a position of the pipe 2 in which the pipe is disengaged from the retainer 21 and has moved in a direction as indicated by arrow 31 , which is in a plane defined by the arc of the bending groove 13.

An advantage of the device according to the invention is that when the pipe 2 is disengaged from the retainer 21 in a direction in a plane defined by the arc of the bending groove 15, the pipe 2 may be supported by the groove extension 29. Due to the groove extension curving in the same direction, the pipe more or less smoothly unrolls from the bending groove 15 onto the groove extension 29 while staying in the plane defined by the arc of the bending groove 15. This reduces the risk of damage to the pipe 2 considerably.

After the pipe 2 has been moved to a position corresponding to the dashed cross section in Fig. 6, the pipe 2 at retainer 21 can be moved in a direction indicated by arrow 33, which direction is perpendicular to direction 31 , i.e. perpendicular to the plane defined by the arc of the bending groove 15, to remove the pipe 2 from the device 1. During this movement, the pipe 2 may still be in contact with the groove extension 29, so that it is preferred that the groove extension terminates at the retainer side thereof with rounded edges, to minimize the risk of damage while taking the pipe 2 out of the device 1.

The groove extension 29 is preferably a real extension of the bending groove 15, so that the groove extension has a cross section with a radius corresponding to the outer diameter of the pipe. Further, the groove extension is preferably formed in an arc around the pivot axis 1 1 with a radius identical to the bending groove 15.

To aid the insertion in and removal of the pipe relative to the device 1 , the groove extension 29 comprises a groove bottom 29a flanked by two groove sidewalls 29b extending from the groove bottom 29a, wherein a length of the groove extension is larger at the groove bottom 29a than at the groove sidewalls 29b. In the embodiment of Fig. 5-7, the length of the groove extension 29 is maximal at the groove bottom 29a and gradually decreases towards a free end 29c of the groove sidewalk

With reference to Fig. 2, the second lever 5 comprises a fork element with two parallel arms 50, 51. Both arms 50, 51 comprise a groove 53, 54 to form the second pivot members. The grooves 53, 54 engage with an axis 55 arranged on the first lever 3, said axis 55 forming the first pivot members.

The first lever also comprises a fork element with two parallel arms 60, 61 which are arranged in between the two arms 50, 51 , such that the axis 55 can engage with the grooves 53, 54 to allow pivotal movement of the second lever relative to the first lever and to be able to remove the second lever from the rest of the device allowing to use the device for bending pipes in small spaces as well. The single axis 55 has the advantage that it can also serve as rotation axis for the groove element 13 at the same time. Alternatively, the first pivot members can be formed by cylindrical protrusions extending from the arms of the fork element of the first lever. The groove and axis or cylindrical protrusions may also be switched, so that the first lever comprises the grooves and the second lever comprises the cylindrical protrusions. The skilled person will understand that other configuration for connecting the first and second lever while allowing pivotal movement are also possible.

The groove element 13 is thus arranged in between the arms 60, 61 of the first lever and the bending element 17 is arranged in between the arms 50, 51 of the second lever.

In the shown embodiment, the fork element of the second lever makes an obtuse angle with the other part of the second lever. This is advantageous when the device is used in small spaces, as the obtuse angle ensures that the device occupies less space or in other words, less space is required to operate the device.

Although the invention has been described by reference to a specific embodiment in Figs. 1 - 7, the skilled person is able to easily envisage modifications and alternatives that still fall within the scope of the invention. This applies to dimensions and ratios, but also to how components are embodied.

For instance, the bending elements is depicted in the Figs, as a rotatable roller to minimize friction, but can easily be embodied as a non-rotating element being in sliding engagement with the pipe during bending.

Further, the groove element may be non-rotatable and thus fixed to the first lever, and the retainer is not necessarily connected to the groove element and can also be fixed directly to the first lever. In the shown embodiment, the first and second lever can easily be disconnected by disengaging the first and second pivot members, but in an alternative embodiment, the first and second pivot members may be configured for permanent engagement.

In an embodiment, the device is at least partially casted using a mould, preferably all components are casted and assembled afterwards. Assembly may comprise welding or glueing.