EP1331050A1

EP1331050A1 - Expulsion device for bars or segments of bars

Info

Publication number: EP1331050A1
Application number: EP03001425A
Authority: EP
Inventors: Fabro Giorgio Del; Marcello Del Fabro
Original assignee: MEP Macchine Elettroniche Piegatrici SpA
Current assignee: MEP Macchine Elettroniche Piegatrici SpA
Priority date: 2002-01-24
Filing date: 2003-01-22
Publication date: 2003-07-30
Anticipated expiration: 2023-01-22
Also published as: ITUD20020013A1; EP1331050B1; DK1331050T3; ES2316657T3; ATE409533T1; DE60323768D1

Abstract

Expulsion device (10) for bars (11), or segments of bars (11a), advancing on a plane of a bending machine (12) to make stirrups, or other shaped elements for reinforcement purposes. The device (10) comprises thruster means (20) movable in a direction orthogonal to the axis of feed (X) of the bar (11), or segment of bar (11a), between a first position of non-interference wherein they are arranged laterally with respect to the bar (11), or segment of bar (11a), and allow it to advance, and a second expulsion position, wherein they act on the bar (11), or segment of bar (11a), to displace it laterally with respect to the axis of feed (X).

Description

FIELD OF THE INVENTION

The invention concerns an expulsion device for segments of bars, also called off-cuts, left over from the shearing and bending of bars pre-sheared to size, or as terminal parts of a roll.
The invention is applied in particular on machines for the bending and shaping of bars able to form stirrups, or other shaped elements for reinforcement purposes. The invention comprises expulsion means cooperating with a shears and/or the rollers of a drawing assembly which feeds the bars towards a bending assembly located downstream of the shears.

BACKGROUND OF THE INVENTION

There are known bending machines for straight bars able to shape stirrups, or other shaped reinforcement elements; such machines substantially consist of a drawing assembly, for example with rollers, able to feed the bars towards a bending assembly, and a shears, located between the drawing assembly and the bending assembly, able to shear the shaped bars to take them to the size corresponding to the linear development of the segments to be formed.
Since this linear development often does not correspond exactly to the length of the sheared bars, a terminal segment of the bars, or off-cut, remains between the drawing assembly and the shears, preventing the start of a new working cycle. The off-cuts must therefore be discharged from the axis of feed of the bars, either manually or by means of suitable expulsion devices.
Conventional expulsion devices normally consist of at least a pair of ejector rollers which are able to intervene after shearing, so that the off-cut is discharged axially, thus freeing the shears and the drawing assembly.
With this solution, however, there is a risk that the discharged off-cut might interfere with the bending assembly, arranged immediately downstream of the shears, or with other operating assemblies which can be present on the bending machine, compromising the correct functioning thereof and in any case obliging the operator to intervene. Moreover, the conventional solution does not guarantee sufficient safety for the operator, since the off-cuts are discharged in an uncontrolled manner and can hit the operator
Moreover, when the off-cuts are very small, the ejector rollers may not be able to intervene.
Another shortcoming is that when it is necessary to discharge the bar rapidly from the machine, due to any malfunctioning thereof, the ejector rollers are not able to perform this operation quickly and efficiently, thus causing long downtimes and slowing down the functioning of the machine.
The present Applicant has devised and embodied this invention to overcome the shortcomings of the state of the art and to obtain further advantages.

SUMMARY OF THE INVENTION

The invention is set forth and characterized essentially in the main claim, while the dependent claims describe other innovative characteristics of the invention.
Purpose of the invention is to achieve an expulsion device for bars or segments of bars in bending machines, in order to make stirrups or other shaped elements, wherein the bars or segments of bars are discharged in such a fashion that, once discharged, the segments of bars do not interfere with the correct functioning of the machine and do not entail risks for the operator.
Another purpose of the present invention is to achieve an expulsion device able to act even on very small segments of bar.
In accordance with these purposes, the expulsion device according to the invention comprises expulsion means movable in a direction substantially orthogonal to the axis on which the bar advances, and cooperating at least with the shearing assembly arranged upstream of the bending assembly. The expulsion means are able to move between a first position of non-interference, wherein they are arranged laterally with respect to the bar being worked and allow it to advance freely, and a second expulsion position, wherein they act on the bar to displace it laterally and discharge it from the axis of feed.
In a preferential embodiment, the expulsion means are arranged immediately upstream of the shearing assembly of the bending machine, and comprise a thruster element with at least a wall orthogonal to the working plane of the machine and able to be moved transversely, by means of a linear actuator to act laterally on the segments to be discharged.
According to another preferential embodiment, the expulsion device has thruster means shaped like an upside-down U or C.
Thus, by activating the actuator, the wall orthogonal to the working plane is displaced transversely and causes the bar or segment of bar to be discharged to fall.
At the side of the machine, there may be suitable means to collect the segments.
In the case of a thruster element shaped like an upside-down C, the expulsion device, in the position of non-interference, can define a cavity inside which the bars being worked are able to slide axially.
According to a variant, the expulsion device comprises two or more thruster elements which can be activated simultaneously or in any case in coordination, and cooperating respectively with the shears assembly and with one or more pairs of rollers of the drawing assembly. If the length of the segment of bar is such that it remains gripped on the rollers, the activation of the expulsion device is preceded by a step of opening the rollers so as to release the grip on said segments.
The device according to the present invention therefore allows to discharge bars or segments of bars of any length, laterally with respect to the machine, so as to prevent the discharged bars from interfering with the correct functioning of the machine.
Moreover, the lateral action of the expulsion means allows to discharge the bars rapidly from the machine so that, if there are malfunctions or breakages, the downtimes are limited and the functioning of the machine is not slowed down.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the invention will be apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

fig. 1 is a view from above of a bending machine equipped with an expulsion device according to the invention, in a position of non-interference;
fig. 2 shows the machine in fig. 1 with the expulsion device in an expulsion position;
fig. 3 is an axonometric view of fig. 1;
fig. 4 is an axonometric view of fig. 2;
fig. 5 shows a variant of fig. 3;
fig. 6 shows the device in fig. 5 in the expulsion position;
fig. 7 shows a first variant of fig. 5;
fig. 8 shows the device in fig. 7 in the expulsion position;
fig. 9 shows a second variant of fig. 5;
fig. 10 shows the device in fig. 9 in the expulsion position.

DETAILED DESCRIPTION OF PREFERENTIAL FORM OF EMBODIMENT OF THE INVENTION

With reference to figs. 1 and 2, an expulsion device 10 for bars 11, or segments of bars 11a, according to the invention is applied to a bending machine 12.
In this case, the bending machine 12 comprises a bending disk 13 able to bend/shape the bar 11, a shears 14 arranged upstream of the bending disk 13, and able to finish the bent bars 11, eliminating the parts in excess with respect to the linear development of the formed shape, a first drawing assembly 15 with pairs of rollers arranged upstream of the shears 14, and able to make the bar 11 advance towards the bending disk 13, and a second drawing assembly 16 arranged downstream of the bending device and able to make the bar 11 advance to shape the trailing ends.
The bending machine 12 also comprises a lead-in channel 17 arranged upstream of the first drawing assembly 15 and able to facilitate the insertion of the bars 11 into the rollers of the latter.
The expulsion device 10 in this case is arranged between the first drawing assembly 15 and the shears 14 and comprises thruster means 20 movable in a direction substantially orthogonal with respect to a nominal axis of feed X of the bar 11 (figs. 3-10), between a first position of non-interference wherein they allow the bar 11 to advance, and an expulsion position, wherein they act on the bar to displace it laterally with respect to the axis X.
The lateral movement of the thruster means 20 is achieved by respective linear actuators 21, such as for example hydraulic cylinders.
In the form of embodiment shown in figs. 3 to 6, the thruster means 20 are shaped substantially like an upside-down C, and comprise a front wall 20a orthogonal to the plane on which the bars 11 advance, a rear wall 20b parallel to the wall 20a and, connected with the actuator 21, an upper wall 20c which joins together the two upper ends of the walls 20a and 20b.
The lower ends of the walls 20a and 20b, on the contrary, rest slidingly on a base plate 22, 50 as to define a closed cavity 23 inside which the bars 11 slide.
The front wall 20a also functions as a protection element for the operator.
In the embodiment shown in figs. 3 and 4, the segments of bars 11a produced by the action of the shears 14 have a relatively limited length, so that a single thruster means 20 is able to displace them laterally, driven by the actuator 21, due to the thrust determined by the inner flank of the rear wall 20b.
This thrust is produced until the segments 11a are no longer supported by the base plate 22 and fall downwards, possibly onto collection means provided for this purpose. During this step the rollers of the drawing assembly 15 open to allow the segments 11a to be discharged.
In the variant shown in figs. 5 and 6, used in the case of segments 11a of a greater size, several thruster means 20 are provided, in this case three, cooperating respectively with the shears 14 and the pairs of rollers of the drawing assembly 15. In this particular case, the thruster means 20 located on the extreme left in the drawings can replace the channel 17, creating a lead-in for the bars 11 to be inserted into the rollers of the drawing assembly 15.
With the device 10 according to the invention it is also possible to laterally discharge the entire bar 11 inserted, in order to accelerate possible maintenance operations in the event of breakdowns or malfunctions.
It is clear, however, that modifications and/or additions of parts can be made to the expulsion device 10 as described heretofore, without departing from the field and scope of the present invention.
For example according to the variant shown in figs. 7 and 8, the thruster means 20 is without the front wall 20a.
According to the variant shown in figs. 9 and 10, the thruster means 20 is also without the upper wall 20c and has only a wall orthogonal to the plane on which the bar advances, functioning as a thruster element.
It is also clear that, although the present invention has been described with reference to specific examples, a skilled person shall certainly be able to achieve many other equivalent forms of expulsion device for bars, or segments of bars, all of which shall come within the field and scope of the present invention.

Claims

Expulsion device for bars (11), or segments of bars (11a), advancing on a plane of a bending machine (12) able to make stirrups, or other shaped elements for reinforcement purposes, characterized in that it comprises thruster means (20) movable in a direction substantially orthogonal to the axis of feed (X) of said bar (11), or segment of bar (11a), between a first position of non-interference wherein they are arranged laterally with respect to said bar (11), or segment of bar (11a), and allow it to advance, and a second expulsion position, wherein they act on said bar (11), or segment of bar (11a), to displace it laterally with respect to said axis of feed (X).
Device as in claim 1, characterized in that the movement between said position of non-interference and said expulsion position is achieved by at least a linear actuator (21).
Device as in the previous claims, wherein said bending machine (12) comprises at least a bending assembly (13), shearing means (14) arranged upstream of said bending assembly (13) and drawing means (15) arranged upstream of said shearing means (14), characterized in that said thruster means (20) are arranged between said drawing means (15) and said shearing means (14), and comprise at least a wall (20b) substantially orthogonal to the plane on which said bar (11) advances and able to slide transversely with respect to said plane.
Device as in claim 3, characterized in that an upper wall (20c), substantially perpendicular, is associated with said substantially orthogonal wall (20b).
Device as in claim 4, characterized in that said thruster means (20) are substantially shaped like an upside-down U with a front wall (20a), a rear wall (20b) and an upper wall (20c), said walls (20a, 20b, 20c) defining a cavity (23) inside which said bars (11) or segments of bars (11a) are able to slide.
Device as in claim 3, wherein said drawing means comprise a drawing assembly with rollers (15), characterized in that said rollers are able to open to allow said bars (11) or segments of bars (11a) to be discharged by said thruster means (20).
Device as in claim 3, characterized in that it comprises a plurality of said thruster means (20) arranged in cooperation with said drawing means (15), said thruster means (20) being able to be driven in coordination in order to act on said segments of bars (11a).