EP1533052A1

EP1533052A1 - Bending machine for tubular elements.

Info

Publication number: EP1533052A1
Application number: EP04102788A
Authority: EP
Inventors: Antonio Maria Pedrazzoli
Original assignee: Pedrazzoli Ibp SpA
Current assignee: Pedrazzoli Ibp SpA
Priority date: 2003-11-19
Filing date: 2004-06-17
Publication date: 2005-05-25
Also published as: ITVI20030233A1

Abstract

A bending machine (1) for tubular elements (T) comprising a base (2) that supports a bending head (5) in which there is a support structure (6) associated with: a bending female die (7), a bending male die (8) opposing the bending female die (7), guide means (10) of the tubular element (T) to be bent and power means (11) to set the bending female die (7) rotating. The guide means (10) belong to a support plate (12) resting on an underlying support counterplate (13) coupled to the support structure (6) through sliding means (14) and associated with shifting means (15) suited to shift it along the shifting direction (Y) defined by the sliding means (14) in order to position the guide means (10) on the right side (D) or on the left side (S) of the female die (7) and of the longitudinal axis (X) of the tubular element (T).

Description

The invention concerns a bending machine particularly suited to be used for bending tubular elements.
It is well known that to bend tubular elements bending machines with bending heads are used, which substantially comprise a support structure with which a female die and a male die opposing each other are associated.
The tubular element to be bent, whose longitudinal axis is kept in stable position by guide means against which it rests, is located between the female die and the male die.
Suitable power means set the female die and the male die rotating to bend the tubular element.
The bending machine generally comprises also a carriage for positioning the tubular element to be bent, which slides on guides obtained in a base.
As far as the bending female die is concerned, it can be carried out with more than one profile, in such a way as to obtain bends with different radiuses, if necessary even bends with variable radius, by shifting the tubular element through the longitudinal movement of the positioning carriage.
The bending machines of the known type described above make it possible to bend the tubular element to the right and to the left and for this purpose they are equipped with two bending heads, one suitable for making the right bend and the other suitable for making the left bend.
Each bending head is therefore provided with a corresponding female die and male die and with a slide with guide means suited to keep the longitudinal axis of the tubular element to be bent in stable position with respect to the corresponding bending head and to the corresponding female die and male die.
In some applications of the invention the two bending heads are positioned one on top of the other, in such a way as to reduce the overall dimensions of the machine in plan view, while in other applications the bending heads are coplanar and positioned side by side.
Both types of application described have the drawback that they are expensive, in fact the bending machine must be constructed with double equipment, that is, with two female dies, two male dies and two slides to support the guide means that keep the longitudinal axis of the tubular element to be bent in stable position.
This invention aims to overcome the above mentioned drawback by carrying out a bending machine that is capable of making right and left bends with a single bending head.
The aim has been achieved through the implementation of a bending machine for tubular elements which, according to the main claim, comprises a base supporting a bending head in which there is a support structure connected to said base, with which the following elements are associated:

a bending female die defining a rotation axis that is orthogonal to the longitudinal axis of said tubular element to be bent;
a bending male die opposing said bending female die and associated with a bending arm that defines the same rotation axis as said bending female die;
guide means of said tubular element to be bent, defining a longitudinal direction parallel to the longitudinal axis of said tubular element and orthogonal to the rotation axis of said bending female die;
power means for setting said bending female die rotating,

The base is provided with longitudinal guides on which a positioning carriage supporting the tubular element to be bent slidingly rests.
In this way the bending machine, with the single bending head with which it is provided, is capable of making right and left bends on the same tubular element being processed and these bends may have variable or fixed radius.
To advantage, the construction of the bending machine object of the invention is less expensive compared to the bending machines of the known type.
Still to advantage, the machine object of the invention is smaller than the equivalent machines already known.
Furthermore, the bending machine object of the invention requires less maintenance than the equivalent machines already known.
The aims and advantages described above will be highlighted in greater detail in the description of a favourite application of the invention illustrated below with reference to the enclosed drawings, in which:

Figure 1 is an axonometric view of the bending machine object of the invention;
Figure 2 is an axonometric view of the bending head of the bending machine object of the invention, in the position in which it makes a right bend on a tubular element;
Figure 3 is a top view of the bending head shown in Figure 2;
Figure 4 is an axonometric view of the bending head of the bending machine object of the invention, in the position in which it makes a left bend on a tubular element;
Figure 5 is a top view of the bending head shown in Figure 4.

An axonometric view of the bending machine object of the invention is shown in Figure 1, where the bending machine is indicated as a whole by 1.
It comprises a base 2 on which there are longitudinal guides 3 on which a positioning carriage 4 slides, said carriage being suited to position a tubular element to be bent T, and it comprises also a bending head indicated as a whole by 5 and positioned at one end of the base.
In the bending head 5 that is represented in different views and different operating phases in the figures from 2 to 5 it is possible to observe a support structure 6 fixed to the base 2 and associated with a bending female die 7 defining a rotation axis Z orthogonal to the longitudinal axis X of the tubular element T to be bent and with a male die 8, opposing the female die 7, associated with a bending arm 9 defining the same rotation axis Z as the bending female die 7.
Axis Z preferably belongs to a vertical plane, while axis X belongs to a horizontal plane.
The support structure 6 is also associated with guide means of the tubular element to be bent T, indicated as a whole by 10, defining a longitudinal direction X' lying on the same horizontal plane on which the longitudinal axis X of the tubular element T lies and therefore orthogonal to the rotation axis Z of the bending female die 7 and to the bending arm 9.
The bending female die 7 is also associated with power means, indicated as a whole by 11, which serve to set it rotating around the above mentioned axis Z, in order to bend the tubular element T.
According to the invention, the guide means 10 belong to a support plate 12 resting on an underlying support counterplate 13 that is coupled to said support structure 6 through sliding means 14 and associated with shifting means 15 suited to shift it along the shifting direction Y defined by said sliding means 14 in order to position said guide means 10 on the right side D or on the left side S of said female die 7 and of said longitudinal axis X of said tubular element T to be bent.
In particular, the guide means 10 comprise two guide slides 16, 17 of the tubular element T positioned side by side and associated with the support plate 12, each one of which defines the longitudinal direction X' parallel and coplanar to the longitudinal axis X of the tubular element T to be bent and is provided with shaped grooves 16a, 17a whose profile can be conjugated to the external profile of the tubular element T to be bent.
The support plate 12 is also provided with actuator means, indicated as a whole by 18, suited to shift the guide means 10 along the longitudinal direction X' and comprising an actuator 18a, preferably but not necessarily of the linear fluid-operated type.
Alternatively, the actuator can also be electric or operated in another way.
As to the sliding means 14 of the support counterplate 13 along direction Y, they are constituted by linear guides 20 interposed between the support counterplate 13 and the support structure 6, while the shifting means of the support counterplate 13 along the linear guides 20 comprise a pinion 21, coupled to the shaft of an electric motor 22 fixed to the support structure 6, which meshes with a rack 23 belonging to the support counterplate 13.
It is obvious that to bend the tubular element T the female die 7 is set rotating by the power means 11 comprising an electric motor 24 fixed to the support structure 6 and a belt 25 forming a closed ring between a first pulley coupled to the motor and not visible in the drawings and a second pulley 26 coupled to the female die 7.
Preferably, but not necessarily, the electric motors 22 and 24 are brushless electric motors and the female die 7 presents several profiles, indicated as a whole by 7a, which can be observed in the figures.
Substantially, therefore, the movements that take place in the bending head 5 are the rotation of the bending female die 7 around the vertical axis Z, as well as the movements of the guide slides 16, 17 of the tubular element T on a horizontal plane along two directions X' and Y orthogonal to each other.
From an operative point of view, when the sliding means are arranged according to the configuration shown in Figures 2 and 3, that is, in position D on the right of the female die 7 and of the tubular element T to be bent, the tubular element T makes contact with the guide slides 17.
The rotation of the bending arm 9 and of the bending female die 7 takes place according to the clockwise direction O shown by the arrow in Figure 3, so that the right bend Cd is made on the tubular element T.
Vice versa, when it is necessary to make a left bend, as shown in Figures 4 and 5, it is necessary to shift the support plate 12 from right to left along the longitudinal direction Y, as indicated by the arrow, through the shifting means 15 until the guide slides 16 reach position S on the left of the bending female die 7 and of the tubular element T to be bent, as shown in Figures 4 and 5.
From this position, the left bend Cs on the tubular element T can be obtained by rotating the bending arm 9 and the bending female die 7 in the anticlockwise direction A indicated by the arrow in Figure 5. The possibility to shift the guide means 10 and therefore the guide slides 16 and 17 in the direction X' parallel to the longitudinal axis X of the tubular element to be bent T allows the tubular element to be guided during the bending process.
Therefore, according to the above description, it is clear that the bending machine object of the invention achieves the goals set. In fact, unlike the equivalent bending machines of the known type, with a single bending head, a single female die and a single slide to support the guide means, moving transversally with respect to the longitudinal axis X of the tubular element T, it is possible to make left and/or right bends on the tubular element in the same processing cycle.
To advantage, it is thus possible to obtain a bending machine that costs less, is smaller and requires less maintenance than the known bending machines.
Obviously, the female dies, the male dies and the guide means can have any shape and profile, according to the profile and size of the tubular element to be bent.
Upon implementation modifications and variants of the bending machine object of the invention may be carried out, which are not described and illustrated in the drawings enclosed hereto. It is evident, however, that any variants or modifications included in the claims expressed here below are to be considered protected by this patent.

Claims

Bending machine (1) for tubular elements (T), comprising a base (2) that supports a bending head (5) in which there is a support structure (6) for the connection to said base (2), said support structure being associated with:

a bending female die (7) defining a rotation axis (Z) orthogonal to the longitudinal axis (X) of said tubular element (T) to be bent;

a bending male die (8) opposing said bending female die (7) and associated with a bending arm (9) that defines the same rotation axis (Z) as the bending female die (7);

guide means (10) of said tubular element (T) to be bent, defining a longitudinal direction (X') parallel to the longitudinal axis (X) of said tubular element (T) and orthogonal to the rotation axis (Z) of said bending female die (7);

power means (11) to set said bending female die (7) rotating,

characterized in that said guide means (10) belong to a support plate (12) resting on an underlying support counterplate (13) coupled to said support structure (6) through sliding means (14) and associated with shifting means (15) suited to shift it along the shifting direction (Y) defined by said sliding means (14) in order to position said guide means (10) on the right side (D) or on the left side (S) of said female die (7) and of said longitudinal axis (X) of said tubular element (T).
Bending machine (1) according to claim 1), characterized in that said guide means (10) comprise two guide slides (16, 17) of said tubular element (T) positioned side by side and associated with said support plate (12), each one of said guide slides (16, 17) being suitable for defining said longitudinal direction (X') parallel to the longitudinal axis (X) of said tubular element (T) to be bent.
Bending machine (1) according to claim 2) characterized in that each one of said guide slides (16, 17) is provided with one or more grooves (16a; 17a) whose profiles can be conjugated to the external profile of said tubular element (T) to be bent.
Bending machine (1) according to claim 2), characterized in that said support plate (12) is provided with actuator means (18) suitable for shifting said guide means (10) along said longitudinal direction (X') parallel to said longitudinal axis (X) of said tubular element (T).
Bending machine (1) according to claim 4), characterized in that said actuator means (18) comprise at least one linear fluid-operated actuator (18a).
Bending machine (1) according to claim 4), characterized in that said actuator means (18) comprise at least one electric actuator.
Bending machine (1) according to claim 1), characterized in that said shifting direction (Y) defined by said sliding means (14) for coupling said support counterplate (13) to said support structure (6) is orthogonal to said longitudinal direction (X') defined by said guide means (10) and to said longitudinal axis (X) defined by said tubular element (T) to be bent.
Bending machine (1) according to claim 1) or 6), characterized in that said sliding means (14) are constituted by linear guides (20) interposed between said support counterplate (13) and said support structure (6).
Bending machine (1) according to claim 1), characterized in that said shifting means (15) of said support counterplate (13) comprise a pinion (21) coupled to the shaft of an electric motor (22) fixed to said support structure (6) and meshing with a rack (23) belonging to said support counterplate (13).
Bending machine (1) according to claim 1), characterized in that said power means (11) to set said bending female die (7) rotating comprise an electric motor (24) fixed to said support structure (6) and a belt (25) forming a closed ring between a first pulley coupled to said motor (24) and a second pulley (26) coupled to said female die (7).
Bending machine (1) according to claim 9) or 10), characterized in that said electric motors (22, 24) are brushless motors.
Bending machine (1) according to claim 1), characterized in that said female die (7) is of the type with more than one profile (7a).
Bending machine (1) according to claim 1), characterized in that it comprises also:

a positioning carriage (4) suited to support said tubular element (T) to be bent in order to place it in front of said bending female die (7);

longitudinal guides (3) carried out on said base (2) and defining a longitudinal sliding direction of said carriage (4) that is parallel to the longitudinal axis (X) of said tubular element (T) to be bent;

power means to make said positioning carriage (4) advance.