EP2127771B1

EP2127771B1 - Folding machine

Info

Publication number: EP2127771B1
Application number: EP08157263A
Authority: EP
Inventors: Inaki Xabier Aizpurua Zendoia
Original assignee: Goiti SCL
Current assignee: Goiti SCL
Priority date: 2008-05-30
Filing date: 2008-05-30
Publication date: 2012-10-17
Anticipated expiration: 2028-05-30
Also published as: EP2127771A1; ES2397551T3

Description

Field of the Art

The object of the present invention is a folding machine of those used for folding and forming metallic sheets.

State of the Art

The applicant is the holder of several patents regarding these types of machines, among which EP 1121996 can be mentioned.
The movement of the blade carrier and of the presser carriage incorporating the movable jaw must be provided in these machines. The most traditional solution to achieve both movements is through hydraulic actuators.
Other solutions using connecting rod and/or eccentric shaft systems instead of hydraulic actuators are also known. The movement of the connecting rods and of the eccentric shafts is carried out through motors or servomotors and epicyclical reduction.
With regard to the movement of the blade carrier, patent US 6,227,028 describes an installation of two opposite folding machines according to an arrangement shown in Figure 11 of said patent. This figure 11 shows how the blade carrier and the presser carriage supporting the movable jaw are driven by means of a motor and connecting rod system.
Patent EP 1609543 describes a solution according to which one of the two blades of the blade carrier has a second folding lip or edge; such that this blade extends upwards and downwards. It further describes that for the drive of the blade carrier, the latter has an eccentric shaft 13 connected at the end opposite to that of the blades and furthermore said blade carrier is connected to a vertical bend arm 12a or 12b. The bend arm 12b is attached at one end to a pivot 17 and at the opposite end to an eccentric shaft 14b; whereas the bend arm 12a is attached at one end to an eccentric shaft 16 and at the opposite end to an eccentric shaft 14a.
According to a solution disclosed in PCT WO2006/043292 , the blade carrier is moved by a kinematic system according to which a closed kinematic chain with five members connected by five kinematic turning pairs is used.
To that end, it uses servomotors and epicyclical reduction instead of traditional hydraulic actuators to control the movements of the blade carrier.
As can be seen in Figure 2, in relation to the front part of the blade carrier, there are respective servomotors 21 and 22 connected to respective pairs of connecting rods 23-25 and 24-26.
At the rear part of the blade carrier there is a servomotor 15 which, through the connecting rods 16 and 17, is connected to a lever 18 which together with elements 18a and 18b forms a structure like a trident.
The use of servomotors and epicyclical reduction in machines for folding and forming metallic sheets is already described in Patent US 6,640,606 .
These already known solutions for obtaining the movement of the blade carrier imply complex kinematic systems as is the case of PCT WO2006/043292 and alignment problems between the blade carrier and the fixed and movable jaws.
With regard to the movement of the presser carriage having the movable jaw, in addition to the traditional solutions using hydraulic actuators, systems by means of a motor and connecting rods are also known, such as that described in Japanese Patent JP9010849 in which the presser carriage 111 is attached to a large connecting rod 127 which at one end is attached to a hinge point 131 and at the opposite end is attached to a motor 125 and connecting rod 129 system.
This solution requires large connecting rods 127. This large size of the connecting rods 127, in addition to involving less robustness and stability, implies transport problems due to a larger volume of the machine and more complex assemblies.

Object of the Invention

The object of the present invention is a folding machine, as defined in the preamble part of claim 1 and known from EP 1 121 996 A2 , having solutions in the movement of the blade carrier and of the presser carriage having the movable jaw.
According to the present invention, the folding machine is characterized by the technical features of the characterizing part of claim 1.
Advantageous embodiments of the folding machine of the invention are the subject-matters of dependent claims 2-4.
According to such embodiments, the horizontal movement of the blade carrier is carried out by respective independent drive mechanisms, each of which is formed by a spindle-nut, rack-pinion or connecting rod-crank mechanism, the drive of which is carried out by means of a servomotor and an epicycloidal reducer.
Thus if there is an alignment error between the blade carrier and the assembly formed by the fixed jaw and the movable jaw, this error can be corrected by actuating either of these two independent mechanisms in an electronic compensation.
If the blade carrier is correctly aligned, then both mechanisms act in a synchronized manner.
The lower movement of the blade carrier is also carried out by means of mechanical transmission members, specifically by means of respective connecting rod-crank or spindle-nut mechanisms driven by a servomotor and an epicycloidal reducer.
With regard to the movement of the presser carriage having the movable jaw, such movement is also carried out by means of mechanical transmission members, specifically by means of several connecting rod-crank mechanisms assembled on respective aligned pins which are driven at their free ends by respective servomotor and epicycloidal reducer assemblies.
The particularity in this case lies in the reduced dimension of the connecting rods which simplifies the transport of the machine as well as its assembly and provides the presser carriage assembly with greater robustness.
The reduced dimension of the connecting rods is achieved by the existence in the machine of a horizontal beam supported by a series of columns; which beam is arranged above the blade carrier, defining a fixed support surface in which the parts to which the lower ends of the connecting rods are hinged are assembled; such that this lower hinge point of the connecting rods moves from the lower area of the machine to the upper part, which allows reducing the longitudinal dimension of the connecting rods.

Description of the Figures

Figure 1 shows a schematic and side elevational view of a folding machine described in EP 1121996 .
Figure 2 shows a schematic perspective view of a folding machine according to the present invention in which the blade carrier (9) is moved horizontally by two independent mechanisms (20); whereas the drive of the presser carriage (1) is provided through short connecting rods (17).
Figure 3 is a perspective view which allows observing the assembly of the connecting rods (17).
Figure 4 is a perspective view showing the mechanisms for the horizontal and vertical drive of the blade carrier (9).
Figure 5 is a perspective view like that of Figure 4 but from an upper perspective.
Figure 6 is a view like that of Figure 2, but with a practical embodiment variant of the two mechanisms (20).
Figures 7 and 8 are respective perspective views in order to be able to observe the drive mechanisms for driving the blade carrier (9) according to the version of the machine shown in Figure 6.
Figures 9, 10 and 11 are views like that of Figure 2 but with practical embodiment variants of the folding machine.
Figure 12 shows a perspective view of the drive mechanisms for driving the blade carrier (9) corresponding to the version of the machine shown in Figure 11.

Detailed Description of the Invention

The object of the present invention is a folding machine, a machine with these features forming the object of European patent EP 1121996 of the same applicant as the present invention having been shown in Figure 1.
In this machine of Figure 1, the presser carriage (1) having the movable jaw (5) pivots with respect to a hinge pin (12), by the thrust of hydraulic actuators formed by hydraulic cylinders (2).
The presser carriage (1) thus pivots by means of the action of the hydraulic cylinders (2), moving the movable jaw (5) closer or further away with respect to the fixed jaw (7).
The hydraulic cylinders (2) are coupled, at the free end of their piston, to a horizontal beam (3) forming part of the fixed structure of the machine.
In addition, the blade carrier (9) incorporating the blades (4 and 6) can move according to a horizontal path on guides (10) by means of the action of a hydraulic actuator formed by a hydraulic cylinder (13).
The blade carrier (9) can also pivot with respect to the pin (11) by the action of hydraulic actuators also formed by hydraulic cylinders (8).
According to the present invention, the folding machine, as shown in Figure 2, moves the presser carriage (1) by means of connecting rod-crank mechanisms, formed by the connecting rods (17) and the cranks (16). These mechanisms can logically be of the connecting rod-eccentric type.
As is observed in Figure 3, according to a non-limiting practical embodiment, there are four connecting rod-crank mechanisms, distributed two by two in respective pins (15). Each of these two pins (15) is moved by a servomotors (18) and epicycloidal reducer (14) assembly.
The connecting rods (17) extend to lower bearings (20) in which they are hinged. Each pair of bearings (20) is assembled on a plate (3") resting on respective integral supports (3') of the horizontal beam (3).
The horizontal beam (3) is supported by a plurality of columns (19) extending from the beam (3) to the base of the machine.
The horizontal beam (3) is thus fixed and when the servomotors (18) act, the pivoting movement of the presser carriage (1) occurs.
Folding machines are already known the presser carriage (1) of which is connected to connecting rod-crank mechanisms, but in the known solutions the connecting rods had to have a large dimension in order to extend from the presser carriage (1) to the base of the machine. In the now proposed solution the connecting rods (17) have a reduced dimension as they only have to extend to the horizontal beam (3), which allows reducing the dimensions of the machine, improving its transport; and offering greater robustness and stability.
With regard to the horizontal movement of the blade carrier (9), the novelty of the present invention is the fact that, instead of carrying it out with a single drive means, it now uses a pair of drive mechanisms (20); such that if there is an alignment error between the blade carrier (9) and the assembly formed by the fixed jaw (7) and the movable jaw (5), this error is corrected by actuating either of these two independent mechanisms (20) with an electronic compensation.
When the blade carrier (9) is correctly aligned, then both mechanisms (20) act in a synchronized manner.
According to the embodiment of the folding machine shown in Figures 2, 3, 4 and 5, the blade carrier (9) has two rear expansions (9') each of which is hinged to a pin (25) assembled between respective plates (26) arranged on a base (27) which, by means of guide-carriages (24) can move on horizontal guides (10).
The end of a spindle (23) is coupled to each pin (25) which spindle is moved by a motor (21) which is directly coupled to a pulley (22). It has been provided that in some cases, if necessary, a reducer can be assembled between each motor (21) and its pulley (22).
Each spindle (23) and motor (21) assembly forms one of the two drive mechanisms (20) for horizontally driving the blade carrier (9).
The blade carrier (9) can pivot with respect to the pins (25) by the action of a mechanism providing the vertical drive of the blade carrier (9) . According to the solution shown in Figures 2, 3, 4 and 5, the vertical drive is provided by means of respective connecting rod-crank mechanism assemblies. Each assembly is formed by a connecting rod (28), hingedly attached at its upper end to the lower part of the blade carrier (9) and at its lower end to cranks (29) moved by a pin (30) driven by a servomotor (32) and epicycloidal reducer (31) assembly.
Figures 6, 7 and 8 show a folding machine like that of Figures 2, 3, 4 and 5 but in which now each of the two drive mechanisms (20) for horizontally driving the blade carrier (9) is formed by a rack-pinion transmission, in which a servomotor (36) moves a pinion (34) engaged to a rack (33) through an epicycloidal reducer (35).
Figure 9 is another possible practical embodiment variant in which the horizontal movement of the blade carrier (9) is again provided by means of two rack (33) and pinion (34) mechanisms (20), but the vertical movement is achieved by means of spindles (37) moved by a motor (39) directly coupled to a pulley (38). A reducer could again be inserted between the spindle (37) and the motor (39) in this case and if necessary.
Figures 10, 11 and 12 show two other possible practical embodiment variants. A folding machine in which both the horizontal movements of the blade carrier (9) and the vertical movements are achieved by means of spindles (23 and 37) is shown in the first of these embodiments. It must be pointed out that the spindles (23 and 37) depicted in the different figures are of the rotating nut type, but can also be of the fixed nut type.
The machine depicted in Figures 11 and 12 has the blade carrier (9) connected to connecting rod (28)-crank (29) mechanisms for its vertical movement.
For the horizontal movement, it maintains the essential feature of using two mechanisms (20), each of which is now formed by a servomotor (43) coupled to an epicycloidal reducer (42) at the outlet of which there is assembled an eccentric (41) connecting with a connecting rod (49). The eccentric (41) could be substituted with a crank.
The different reducers (31, 35 and 42) may or may not be of the epicycloidal type.

Claims

A folding machine comprising a blade carrier (9) which has respective rear expansions (9'), each of which, through a hinge pin (25), is coupled to a respective mechanism (20), the actuation of which gives rise to a horizontal movement of the blade carrier (9); such that this horizontal movement is provided by means of two independent mechanisms (20) acting independently during the alignment of the blade carrier (9) and in a synchronized manner in the work phase of the blade carrier (9); and connecting rods (17) with a reduced longitudinal dimension extend between a presser carriage (1) and a fixed horizontal beam (3) arranged at the upper part of the machine for the drive of said presser carriage (1), characterized in that the connecting rods (17) with a reduced longitudinal dimension are grouped according to two pairs in which cranks (16) or eccentrics are connected in each pair of connecting rods (17), which cranks or eccentrics are assembled in a pin (15) moved by a servomotor (18) and reducer (14) assembly.
A folding machine according to claim 1, characterized in that each of the two drive mechanisms (20) for horizontally driving the blade carrier (9) is formed by a motor (21) and spindle (23) assembly or a rack (33) and pinion (34) assembly or a crank/eccentric (41) and connecting rod (40) assembly.
A folding machine according to claim 1 or 2, characterized in that the pins (15) horizontally aligned with one another are arranged at the upper part of the machine, with their inner end being free and the outer end being connected to the reducer (14).
A folding machine according to any one of claims 1 to 3, characterized in that the horizontal beam (3) is fixed to the upper end of a series of vertical columns (19), secured at their lower end to the base of the machine, said horizontal beam (3) having on its upper plane support parts (3' and 3") on which the bearings of the lower end of the connecting rods (17) are supported.