[0001] This invention concerns a bending method for a double shaping machine, and the relative
double shaping machine with movable winged elements as set forth in the respective
main claims.
[0002] The invention is used preferably, but not only, to shape large dimension round pieces
used for reinforcement purposes in the building trade, but can in any case be used
to bend pipes, bars or other sections in general, of whatever section.
[0003] In the following description, for practical reasons, we shall refer to the specific
use of the invention for round pieces for reinforced concrete and therefore the term
round piece shall be taken to include any section whatsoever which may be used to
make bars and/or brackets for reinforcement purposes.
[0004] The term round piece shall also be taken to include bundles of round pieces placed
one on top of the other and shaped at the same time.
[0005] The state of the art covers shaping machines used to make bars and/or brackets for
reinforced concrete in the building trade. These machines are normally structured
to include a double shaping station, each one including its own bending assembly,
so as to allow two bending operations to be carried out at the same time.
[0006] At least one of the bending stations is movable on guides, which allows the station
to be brought nearer to or distanced from the other according to the distance between
the subsequent bending operations.
[0007] There is normally at least one gripper element between the two bending stations;
the gripper element may be movable with respect to the bending stations and its function
is to guide and retain the round piece which is to be shaped, and also to contrast
the bending action.
[0008] The bending assemblies of this type of shaping machine substantially consist of a
rotary disk with a central contrasting pin and a peripheral bending pin. The round
piece which is to be bent is inserted between the two pins of each bending assembly
and then it is shaped by the disk rotating in a desired direction and at a desired
angle according to the geometry of the piece required.
[0009] This conformation of the bending assembly has proved to be unsatisfactory, however,
as it often causes undesired deformations of the round piece in proximity of the contrasting
pin, since in this zone the round piece is not sufficiently contained laterally.
[0010] In order to overcome this shortcoming, the central contrasting pin has been replaced
by a contrasting element associated with the rotary disk and comprising a hollow which
contains the round piece as it passes through; this element is elongated lengthwise
and is known as a winged element.
[0011] This solution is adopted, for example, in DE 94 06 880 and in EP-A-0 015 354.
[0012] The winged element functions as a contrasting element so that the round piece is
laterally contained for an extended portion and is therefore less subject to deformation
on the horizontal plane in the zone of the winged element and during the bending step.
[0013] Another problem which has been found in shaping machines known to the state of the
art concerns the displacement of the bending pin from one side to the other with respect
to the piece to be shaped, so as to make it possible to perform left- and right-hand
bends to 90° and more on the same bar or on the same bundle of bars.
[0014] Because of the structure of these machines for shaping large dimension round pieces,
it is not possible to temporally lower the rotary disk on which the bending pin is
attached below the working plane so that the bending pin can pass below the piece
which is to be shaped and then pass to the other side thereof.
[0015] Some embodiments have proposed a bending pin of the retractable type, including a
working position where it emerges completely from the rotary disk, and a second transfer
position where it is lowered below the disk and is taken from one side to the other
of the piece to be shaped in relation to the bend to be made.
[0016] This solution however makes it necessary to use rotary disks of a particularly complex
structure, and has proved inefficient against the slightest deformation of the bending
pin.
[0017] In fact, the diameters of the round pieces to be worked (even as much as 50 mm) and
the considerable power of the machines often cause the deformation and/or inclination
of the bending pin which is therefore difficult to move if it is to be lowered into
a retraction seating.
[0018] Moreover, the actuation systems which are required to give high power to the bending
assembly cause further difficulties in the lowering of the bending pin below the working
plane.
[0019] Another proposed embodiment includes two bending pins arranged separated at a distance
on the same rotary disk, one for right-hand bends and the other for left-hand bends,
but with this solution it is not possible to achieve bends of more than about 45°.
[0020] Yet another solution includes grippers outside the relative bending station which
are activated in order to temporally lift the round piece and allow the bending pin
to pass from one side to the other, by means of rotating the rotary disk. However
this solution causes problems because of the excessive distance between the axis of
the bending station and the elements which lift the round piece.
[0021] Yet another solution teaches to use a bending disk bearing a central contrasting
pin associated with a peripheral bending pin and another disk, outside the first,
bearing another pair of contrasting pins.
[0022] This solution is complex and does not solve the problem of allowing the bending pin
to pass efficiently and simply from one side of the bundle to the other.
[0023] DE 94 06 880 describes a shaping machine with two bending stations between which
there is a fixing assembly which is also movable, in which each bending station has
a bending assembly with a rotary disk bearing a contrasting element of the type with
a lengthwise guide and a bending pin arranged on the periphery.
[0024] DE'880 substantially teaches to include command means so as to automatically define
the position of the fixing assembly with respect to the two bending stations in such
a way that the fixing assembly is always located at the centre of the two bending
stations during the bending step.
[0025] This document does not propose any solution to carry out consecutive right- and left-hand
bends even of 90° on the same round piece, using a single bending pin.
[0026] DE'880 only provides an expulsion device to extract the bars from the bending heads;
the expulsion device intervenes at the end of the bending operations.
[0027] A further disadvantage of shaping machines known to the state of the art is that
there is a large accumulation of scale and dirt in the channels through which the
round pieces have to pass and also on the working plane. This is caused by the type
of material which is being worked, which normally consists of bars taken from the
warehouse or store rooms exposed to environmental factors.
[0028] This dirt accumulates particularly in the contrasting elements of the longitudinal
guide type, and can in the long term begin to interfere with the bending operations
and create considerable operational problems which have an effect on the quality of
the final product.
[0029] The present applicants have designed, tested and embodied this invention to overcome
the shortcomings of the state of the art and to provide further advantages.
[0030] This invention is set forth and characterised in the main claim, while the dependent
claims describe variants of the idea of the main invention.
[0031] The purpose of the invention is to provide a shaping machine with contrasting elements
of the longitudinal guide type, or wings, which will allow the bending pin to move
from one side to the other of the round piece to be shaped, using a system which is
structurally simple, rapid and functional, regardless of the diameter of the round
piece to be shaped and/or the type of bending to be performed.
[0032] It is thus possible to achieve a bending method wherein right- and left-hand bends,
even of 90°, are carried out in succession, using a single bending pin mounted on
the periphery of the rotary bending disk.
[0033] A further purpose of the invention is to obtain this movement with a system which
will improve and accelerate the production cycle of the machine, and make it more
versatile without needing substantial changes to be made in the functional parts thereof.
[0034] Another purpose of the invention is to allow the dirt and scale which has accumulated
in the hollow through which the round piece passes to be automatically discharged
from the contrasting winged elements.
[0035] In its general structure, the shaping machine according to the invention is substantially
of the conventional type and includes two movable bending stations, each of which
is equipped with a bending assembly with a rotary bending disk on which a winged contrasting
element and a peripheral bending pin are mounted.
[0036] In an intermediate position between the two bending stations, the machine includes
a gripper element, which is also movable with respect to the two bending stations,
to retain and guide the round piece to be shaped.
[0037] According to the invention, each winged element is associated with at least an actuator
which allows it to be raised with respect to the rotary disk, whenever it is necessary
to displace the bending pin from one side to the other of the round piece to be shaped
so as to perform consecutive bends to the left and right of up to 90° and more.
[0038] This movement of the winged element is activated in the intermediate steps between
one bending cycle and the next and causes the round piece, or bundle of round pieces,
enclosed therein to be lifted by a height at least mating with that of the bending
pin.
[0039] The lifting of the winged element, and therefore of the round piece enclosed therein,
makes it possible to rotate the disk on which the bending pin is mounted and therefore
to make the pin pass under the round piece so as to allow it to be correctly positioned
on the other side from that where the previous bend took place.
[0040] Once the bending pin has been positioned, the actuator is repositioned to take the
winged element back to its seating, which is associated with the rotary disk, so as
to perform a new bending operation on the round piece: this bend is made in the opposite
direction to the previous one.
[0041] According to a first embodiment, the winged element is raised on a plane substantially
perpendicular to the working plane and therefore to the rotary disk, with the winged
element being maintained substantially parallel to that plane.
[0042] According to a variant, the winged element is raised with a rotation movement, which
causes it to be inclined towards the outer part of the bending station; in this embodiment
the winged element is constrained by hinge means to the structure of the machine at
its rear edge.
[0043] In this embodiment, by inclining the winged element, it is possible to discharge
the waste or other dirt from the guide channel of the winged element itself.
[0044] It is also possible to prevent or at least limit the dirt entering the housing hole
of the winged element pin.
[0045] According to another variant, the gripper element placed between the two bending
stations is associated with an actuator which allows the gripper element, and therefore
the round pieces held therein, to be raised or lowered as necessary in a coordinated
manner with the movements of the winged elements.
[0046] The fact that the gripper element is movable gives further support to the round piece
as it is being raised and therefore prevents deformations and flections thereof.
[0047] Therefore the shaping machine considerably reduces the working times of the production
cycle, whatever the geometry of the bending operation or the diameter of the round
pieces.
[0048] In the event that the round pieces as they are raised should bend downwards on the
rotary disk and thus not ensure a sufficient space for transit, the bending pin can
rotate through the widest angle of rotation in such a way that it passes below the
winged element and thus is taken to the correct position with respect to the round
pieces.
[0049] The attached figures are given as a non-restrictive example and show some preferred
embodiments of the invention as follows:
- Fig.1
- shows a view from above of the shaping machine according to the invention;
- Fig.2
- shows a side view of the shaping machine as in Fig.1;
- Fig.3
- shows a detail of the shaping machine in Figs.1, 2 with the winged elements raised;
- Fig.4
- shows a variant of Fig.3.
[0050] The shaping machine 10 for round pieces 16 for reinforced concrete according to the
invention includes two bending stations 10a, 10b arranged in a line and movable on
rails 11 so as to move closer to/further from each other according to the working
cycle.
[0051] Each bending station 10a, 10b comprises a bending assembly 12 consisting of a rotary
disk 13 on the periphery of which there is a bending pin 14 solidly associated.
[0052] In cooperation with the rotary disk 13 and the bending pin 14 there is a winged contrasting
element 15, equipped with a longitudinal hollow through which the round piece 16 passes
lying on a parallel plane to the rotary disk 13.
[0053] In an intermediate position between the bending stations 10a, 10b there is a gripper
element 17 suitable to retain and guide the round pieces 16 during the bending step.
[0054] The gripper element 17 may also be movable with respect to the bending stations 10a
and 10b so as to maintain a desired reciprocal position with respect thereto, during
the bending cycle.
[0055] According to the invention, each winged element 15 is associated with at least a
relative actuator 18.
[0056] According to a variant, there are two or more actuators 18 for each winged element
15.
[0057] The actuator 18 allows the winged element 15 to be raised with respect to the working
plane defined by the rotary disk 13, at least to a point where the lower edge 15a
of the winged element 15, or the round piece 16 placed lower down, is at a greater
height than the top 14a of the bending pin 14.
[0058] The raising of the winged element 15 makes it possible, by rotating the rotary disk
13 in either one direction 24 or the other (Fig. 1), for the bending pin 14 to pass
from one side of the round pieces 16 to the other, so as to bend the round piece 16
in the opposite direction to the previous bending operation.
[0059] Then, when a particular bend has been achieved, for example, to the right, the actuator
18 is activated, the rotary disk 13 is rotated until the bending pin 14 is taken to
the opposite side of the round piece 16, then the actuator 18 carries the winged element
15 back to its working position, the round piece 16 is made to advance lengthwise
as far as the position of the new bend, and then the new bend is achieved with an
opposite direction to that of the previous bend.
[0060] In a first embodiment as shown in Figs. 2, 3, the stationary element 18a of the actuator
18 is solidly associated with the housing structure 19 of the relative bending station
10a, 10b, in a retracted position inside the said structure, while the movable element
18b of the actuator 18 is solid at the lower part with the winged element 15 in an
outer area where it cannot come into contact with the rotary disk 13.
[0061] According to this solution, the winged element 15 is raised on a plane substantially
perpendicular to the plane on which the round pieces 16 lie, the winged element being
maintained substantially parallel to this plane.
[0062] As it is raised/lowered, the winged element 15 is guided by a pin 20 cooperating
with a mating central hole 23 made in the housing structure 19 and communicating with
the central hole on the rotary disk 13.
[0063] According to the variant shown in Fig. 4, the winged element 15 is rotated as it
is raised and is therefore inclined downwards on the side of the relative bending
station 10a or 10b placed in front of the complementary bending station 10b or 10a.
[0064] This embodiment involves no direct intervention on the housing structure 19 of the
bending station 10a, 10b, it occupies no inner spaces inside the housing structure
19, and moreover, it is possible, with this embodiment, to discharge outwards any
scale or other dirt which has accumulated in the guide channel of the winged element
15, preventing this dirt from going onto the working surface of the housing structure
19 and/or penetrating inside the hole 23.
[0065] In this embodiment, the actuator 18 is placed outside the housing structure 19 and
has one of its ends constrained to the said structure; in this case, the actuator
18 is attached in an oscillating manner to the housing structure 19 on a bracket element
21.
[0066] The other end of the actuator 18 is pinned to the rear end 15b of the winged element
15 in an area which does not come into contact with the round pieces 16.
[0067] The winged element 15 is connected to the housing structure 19 in proximity with
its lower rear end 15c by means of a hinge constraint 25, and can oscillate on a vertical
plane substantially corresponding with the plane on which the round pieces 16 lie.
[0068] The winged element 15 is raised or inclined by the action of the movable element
18b of the actuator 18.
[0069] In this case, the lower end of the pin 20 is advantageously reamed so as not to come
into contact with the walls of the hole 23 as the winged element 15 is raised and
rotated.
[0070] According to the embodiment shown in Fig. 2, the gripper element 17 is associated
with its own actuator 22 which allows it to be raised or lowered in conjunction with
the movement of the winged elements 15.
[0071] In this embodiment, when one or both winged elements 15 are raised, the gripper element
17 is also raised, which gives support to the round pieces 16 in the event that there
is a great distance between the stations 10a, 10b and such as to lead to unwanted
flections and deformations of the round pieces 16.
1. Bending method for a double shaping machine to bend metallic sections, either individually
or in bundles, such as round pieces for use in reinforced concrete and suchlike for
making consecutive left-hand and right-hand bends of 90° and more, the shaping machine
comprising two bending stations (10a, 10b) of which at least one is movable lengthwise
with respect to the other, there also being included between the two bending stations
(10a, 10b) a gripper element (17), each of the bending stations (10a, 10b) comprising
a respective bending assembly (12) consisting of a rotary disk (13) including a winged
contrasting element (15) and a bending pin (14) arranged on the periphery, the method
being characterised in that, in order to carry out two consecutive bends, in opposite
directions to each other, on the same round piece (16), the method includes the following
steps:
- the first bend is made on the round piece (16);
- the winged contrasting element (15) is raised, and consequently the round piece
(16) contained therein is also raised, up to a level at least higher than the top
(14a) of the bending pin;
- the rotary disk (13) is rotated in one or another direction (24) so as to carry
the bending pin (14) to the opposite side of the round piece (16) with respect to
the position occupied for the first bend to be made;
- the winged contrasting element (15) is re-positioned in cooperation with the rotary
disk (13);
- the round piece (16) advances to a position corresponding to the next bend to be
made;
- a bend is made in the opposite direction to that of the bend made previously.
2. Bending method as in Claim 1, in which the winged contrasting element (15) is raised
on a plane substantially perpendicular to the plane on which the round pieces (16)
lie.
3. Bending method as in Claim 1, in which the winged contrasting element (15) is oscillated
rotating with respect to the plane on which the round pieces (16) lie, in a direction
facing outwards with respect to the relative bending station (10a, 10b).
4. Method as in any claim hereinbefore, in which, when the winged contrasting elements
(15) are raised, the round piece (16) is raised in a mating manner also in correspondence
with the intermediate gripper element (17) between the two bending stations (10a,
10b).
5. Double shaping machine with winged contrasting elements (15) to bend metallic sections
such as round pieces (16) for use in reinforced concrete in the building trade or
suchlike, the machine comprising two bending stations (10a, 10b) arranged in a line
of which at least one (10b) is movable lengthwise with respect to the other (10a),
there also being included between the two bending stations (10a, 10b) at least a gripper
element (17), each of the bending stations (10a, 10b) comprising a structure (19)
to support a respective bending assembly (12) consisting of a rotary disk (13) including
a winged contrasting element (15) and a bending pin (14) arranged on the periphery,
the winged element (15) comprising a channel for the passage and lateral containment
of the round pieces (16) which are to be shaped, the machine being characterised in
that each winged element (15) is associated with an actuator (18) to raise the winged
element (15) with respect to the bending plane defined by the rotary disk (13) by
a level correlated to the height of the bending pin (14) and to the lower level on
which the round piece (16) lies.
6. Shaping machine as in Claim 5, in which the actuator (18) is associated with the housing
structure (19) of the relative bending station (10a, 10b).
7. Shaping machine as in Claim 5 or 6, in which the actuator (18) is arranged at least
partly inside the structure (19) and has the actuation element (18b) movable on an
axis substantially perpendicular to the plane on which the round piece (16) lies.
8. Shaping machine as in Claim 5 or 6, in which the actuator (18) is arranged at least
partly outside the structure (19) and has the actuation element (18b) movable on an
inclined axis with respect to the plane on which the round piece (16) lies.
9. Shaping machine as in any claim from 5 to 8 inclusive, in which the winged element
(15) includes a lower guide pin (20) cooperating with a mating hole (23) in the rotary
disk (13) and in the housing structure (19).
10. Shaping machine as in any claim hereinbefore, in which the gripper element (17) is
associated with its own lifting actuator (22) which is functionally governed by the
activation of at least one actuator (18) associated with the winged element (15).