Patent Application
20210031255
This is a non-provisional application which claims priority to French Application No. 1908654 filed Jul. 30, 2019, the entire contents of which is hereby incorporated by reference.
The present invention relates to the field of tube bending and in particular to adaptations making it possible to optimize the bending operation.
A tube bending machine conventionally comprises a bending roller as well as a crease erasing member.
By means of movable jaws, the tube placed in the bending machine is bent around the bending roller.
The function of the crease erasing member, also called the crease erasing insert, is to avoid, by being in contact with the tube, the creation of creases at the intrados of the bent portion, in particular for difficult bends, that is to say for:
This crease erasing member is a fixed wear part which comes as close as possible to the bending roller, the latter turning during the bending of the tube. The positioning of the crease erasing member relative to the bending roller must be very precise in order to operate efficiently and above all not to cause the said crease erasing member to break, this member being very fragile.
Indeed, the latter is conventionally produced in special materials allowing both the guiding and the sliding of the tube during deformation.
The crease erasing member is mounted on a crease erasing member support, usually attached to the bending head. This crease erasing member support has settings to adjust the position of the crease erasing member relative to the bending roller.
A disadvantage of the bending operation lies in the adjustment of the position of the crease erasing member relative to the roller. Indeed, this adjustment requires know-how and therefore one or more particularly qualified operators. In addition, the time required for this adjustment, which depends on said know-how, can be very long.
In addition, incorrect adjustment can result in premature wear and/or breakage of the crease erasing member, which is a fragile and expensive part.
For these reasons, changing the bending tool can therefore require a particularly long operation that affects the productivity of the bending operation.
When several stacked bending rollers are associated on the same axis of the same bending head, with which therefore several erasing members cooperate, the tool is called multi-heights tool. It is understood that in this configuration, for the same reasons as those mentioned above, the bending tools of the prior art are complex and not very rigid.
Thus, current bending devices are expensive and fragile.
For example, U.S. Pat. No. 7,360,385 discloses a tube bending device of the type comprising at least one bending roller mounted to be rotatably movable with respect to a frame and at least one crease erasing member. The design of this device increases the number of parts, presents problems of size and positioning accuracy.
Considering the above, the applicant conducted research to solve the drawbacks of the bending devices of the prior art.
This research has resulted in the design and production of an innovative bending tool that offers a new relationship between the bending roller and the associated crease erasing member, a configuration that solves the drawbacks aforementioned.
According to the invention, the tube bending device comprises at least one bending roller mounted so as to be rotatably movable relative to a frame and at least one crease erasing member. This device is specific in that it includes a plate designed with:
This feature is particularly advantageous in that the crease erasing member and the bending roller are designed as an assembly, but are free to rotate one with respect to the other, which is particularly innovative. The roller and the crease erasing member form a compact unit.
Such a design eliminates the operation of adjusting the crease erasing member relative to the bending roller since these elements are positioned relative to each other by the plate. The adjustment is made once and the tool change does not disturb said settings since the roller and crease erasing member assembly is changed. Indeed, by providing guide surfaces to implement a pivot connection relative to the roller, the plate allows the positioning of the crease erasing member that it receives relative to the axis of rotation of said roller.
Thus, by systematically associating each roller with a crease erasing member pre-positioned relative to the axis of the roller, the tool change is much faster and the experience or know-how of the qualified operator, which was previously necessary, is no longer essential.
According to another particularly advantageous characteristic of the invention, the device comprises an independent crease erasing interface which is inserted between the plate and the crease erasing member. The presence of an interposed part can serve as a mechanical interface between the plate and the crease erasing member, allowing finer adjustments. This interface therefore has the function of the crease erasing member support known from the prior art but, in accordance with the invention, is designed to form an assembly with the plate (and not the frame) which therefore positions it with respect to the axis of rotation of the roller.
According to another particular characteristic of the invention, said roller comprises an upper flat surface and a lower flat surface from one of which outwardly projects at least one coaxial cylindrical projection, said plate being pre-formed with at least a bore allowing the guiding of the cylindrical surface of said projection.
Understandably, the plate according to the invention can have different shapes. Among these, according to another particular characteristic of the invention, said roller comprises an upper flat surface and a lower flat surface from each of which outwardly projects a coaxial cylindrical projection, said plate being comprised of two half-plates, each of which being pre-formed with a bore allowing the guiding of the cylindrical surface of said projection.
The roller is therefore held between two half-plates which leave it free to rotate and which receive the crease erasing member directly or through a crease erasing interface.
According to another particularly advantageous characteristic, when several rollers are stacked, the two half-plates are common to the stack of rollers and to the crease erasing members. The cylindrical guide projections then are only provided on the lower flat surface of the roller located at the bottom of the stack and on the upper flat surface of the roller located at the top of the stack. The device is then particularly compact and precise. It does not require the presence of an additional central shaft, the length of which would depend on the number of rollers to be stacked.
According to another particularly advantageous characteristic of the invention, the crease erasing member is pivotably connected to the plate about an axis parallel to the axis of rotation of the roller, thus allowing rotation of the crease erasing member on a limited number of degrees, allowing the crease erasing member to adapt to the constraints to which the tube is subjected.
When the device includes an independent crease erasing interface, the latter is pivotably connected about an axis parallel to the axis of rotation of the roller allowing a rotation of the interface, and therefore of the crease erasing member, on a limited number of degrees.
The connection between the plate and the crease erasing interface or between the plate and the crease erasing member can receive positioning adjustment means. It will nevertheless be understood that this adjustment is not equivalent to that known from the prior art since when the device according to the invention is moved, the positioning adjustment does not have to be done again.
According to another particularly advantageous characteristic of the invention, the cylindrical projections do not project beyond the outer surfaces of the half-plates. This compactness of the assemblies formed by the assembly of the bending roller and erasing member elements makes it easier to stack the tools. Thus, the device of the invention adopting such a configuration facilitates the superposition:
By receiving the device or devices according to the invention, the design of the tooling is facilitated. It is the same for its installation.
According to another particular characteristic of the invention, said cylindrical surface of the cylindrical projection is pre-formed with a groove opposite to a corresponding groove pre-formed in the cylindrical surface of the guide bore, a plurality of balls being interposed between the grooves in order to guide in rotation.
The creation of a ball bearing for the purpose of guiding the rotation makes it possible to take better address the constraints of the bending and guarantees good guidance and therefore good positioning of the crease erasing member along the whole bending operation.
The fundamental concepts of the invention having been explained above in their most elementary form, other details and characteristics will become more clearly apparent with the following description and with reference to the accompanying drawings, describing, by way of non-limiting examples, embodiments of a bending device according to the invention.
As illustrated by
The plate 300 is fixed in rotation to the frame B by the key 400.
The rolling surface of the roller 200 is equipped with a jaw 210 opposite which the movable jaw 110 of the bending arm 100 is positioned, the jaws facing each other. The end of the tube to be bent (not shown) fits between these jaws 110 and 210 before bending, which jaws are tightened (arrow F2) and the rotation according to the arrow F1 around the roller 200 starts as illustrated in
As illustrated by
According to an embodiment not shown, said plate is made in a single part equivalent to a single half-plate, guiding the roller at only one of its flat surfaces.
The start of the rotation according to the arrow F1 of the roller 200 is illustrated by the drawing of
According to the illustrated embodiment, the crease erasing interface 600 and therefore the crease erasing member 500 are pivotally mounted (arrow F3) relative to the plate 300 about an axis parallel to the axis of rotation of the roller 200 and according to a limited number of degrees in order to allow an angular movement allowing an adaptation of the crease erasing member 500 to the constraints to which it is subjected during the bending.
In more detail, as illustrated in
To this end, each half-plate 310 and 320 consists of a flat sheet cut so as to be provided with:
The large central hole 311 and 321 serves to receive, guide and retain the roller 200.
The small side hole 312 and 322 is used for receiving, guiding and retaining the crease erasing interface 600.
The notch 313 and 323 is intended to cooperate with the key 400 fixed to the frame (see
As illustrated, the crease erasing interface 600 is inserted between the inner faces of the half-plates 310 and 320 facing each other, and receives the crease erasing member 500. Cylindrical projections 610 projecting from the crease erasing interface cooperate with the holes 312 and 322. The positioning of this crease erasing member 500 relative to roller 200 can therefore be very precise and positioned only once without the movement of the device disturbing it. A connecting spacer 330 is inserted between the two half-plates 310 and 320 to ensure the connection between the latter while allowing the rotation of the crease erasing interface 600 and of the roller 200. This spacer 330 is pre-formed to take up the profile of the notches 313 and 323 and also cooperates to the connection with the key 400.
Said roller 200 comprises an upper flat surface 230 and a lower flat surface 240 from each of which outwardly projects a coaxial cylindrical projection (only the one numbered 231 appears due to the point of view).
These cylindrical projections will cooperate with the cylindrical surfaces of the holes 311 and 321 formed in the half-plates 310 and 320 for the purpose of guiding and retaining the roller 200.
As illustrated in the drawing of
It is thus understood that such a configuration favors the use of the same device in the opposite direction of bending: it is indeed sufficient to turn the device D as illustrated in
According to a non-illustrated embodiment, said cylindrical surface of the cylindrical projection (only 231 appears) is pre-formed with a groove located opposite a corresponding groove pre-formed in the cylindrical surface of the guide bore (311 and 321), a plurality of balls (not shown) being inserted between the grooves in order to guide in rotation.
As illustrated, a plurality of elements are used in common in this stacked configuration.
Thus, two crease erasing members 910 and 920 (one for each roller) are necessary but a single crease erasing interface 930 ensures their fixing and their positioning relative to the roller with which it cooperates. This crease erasing interface 910 is linked to the upper half-plate 810 and to the lower half-plate 820. Likewise, a single connecting spacer 830 is implemented.
It is understood that the bending devices which have been described and shown above have been described and shown for the purpose of disclosure rather than limitation. Of course, various arrangements, modifications and improvements can be made to the above examples, without departing from the scope of the invention. It is thus understood that despite the fact that the illustrated embodiments illustrate the presence of a crease erasing interface, the plate can as well directly receive the crease erasing member without an intermediate part in accordance with the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1908654 | Jul 2019 | FR | national |
