[0001] This application claims the benefit of priority of prior Greek national application no. GR-20120100138 deposited on March 5, 2012 and assigned a filing date of March 9, 2012, and the entirety of Greek application no. GR-20120100138 is expressly incorporated herein by reference in its entirety and as as to all its parts, for all intents and purposes, as if identically set forth in full herein.

TECHNICAL FIELD

[0002] The present invention relates to a method and system for the production of spacers 2 from wires, rods, or materials of diverse prismatic cross section; as well as meshes of wire, or concrete-reinforcing rods, or tubes, or material of prismatic cross section. Such spacers 2 are placed inside wooden or metallic molds so as to define the location of the reinforcement of the concrete plates. These spacer meshes are produced from initial mesh 1 that may be produced at a mesh welder. The development of such mesh into spacers occurs as follows. The initial mesh is situated along its longitudinal direction in a machine including grippers seated on carriers so as to be freely movable along this longitudinal direction of the product. However, a central gripper is stationary, whereas every second gripper may be moved also perpendicular to the longitudinal direction by the action of a cylinder. With the action of these cylinders, the starting product is deformed, and the carriers of the grippers are subjected to relocation as a result of the pull of the longitudinal wires of the starting product as the final product is formed.

BACKGROUND ART

[0003] The usual practice in production of spacers is their formation at presses with the use of suitable tools. An initial level mesh is introduced into a machine that has disposed both stationary and movable deformation tools, and where the movable deformation tools may be moved by pneumatic or hydraulic cylinders so that by their action the mesh is formed in the desired shape or form. SUMMARY OF INVENTION

TECHNICAL PROBLEM

[0004] This above referred-to methods disadvantageous^ require adjustment or even changing of tools for different diameters of longitudinal wires. Furthermore, the quality of the produced product is disadvantageous ly affected by the elastic recovery of the longitudinal wires that, in turn, is affected negatively as a result of slipping of the wires inside these tools. The result is always a disadvantageous divergence of the dimensions of the produced spacer from the desired form.

SOLUTION TO THE PROBLEM

[0005] Advantageous solutions may be found via systems and methods that locate grippers (3,4,5,6,7) at initial locations, then place material (1) inside the grippers on an axis (XX'). By energizing the grippers to hold the material at their respective locations (BC, DE, FG, HI, JK) and then energizing respective cylinders (23,24) to transpose the respective locations (DE, HI) corresponding to the respective grippers, respectively, perpendicularly relative to the axis (XX'), the product spacer (2) is deformed. This moves respective plate carriers (14,15) parallel with the axis (XX ') via the linking of respective intermediate longitudinal wires (E'F', G'H') of the product (2), and also moves respective carriers (16,17) of respective grippers parallel with the axis (XX ') via the linking of respective intermediate longitudinal wires (CD', IT) of the product (2). A bending of respective end sides (AB, KL) of the material (1) by the action of respective bending mechanisms (81,82) seated on the respective carriers (16,17) of respective grippers, may be made either at the beginning, the duration or the end of deformation. In finishing, such systems and methods open the grippers and deliver the product spacer (2).

[0006] According to the invention, this object is achieved by systems having the features of patent claim 1, and by processes and methods having the features of patent claim 9. Advantageous configurations and further developments of the invention are evident from the dependent claims and from the description in combination with the figures of the drawings. ADVANTAGEOUS EFFECTS OF INVENTION

[0007] The systems and methods may be understood to present many advantages, especially notably in that the formation of spacers now does not depend on the diameter of the longitudinal wires. Furthermore, the adjustments of the mechanism assembly are comparatively simple, that is are only the boundaries of motion of the carriers.

Additionally, the forces of deformation are small because the longitudinal wires are bent freely and are not compressed in the tools. Thus, the instant invention presents

advantageous systems and methods that may produce spacers from level starting mesh, flexibly, with excellent quality and low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Aspects of systems and methods according to the present invention may be understood from the following description and from the attached drawings, wherein systems and methods are presented in an exemplary manner, and where parts which are the same or similar are provided with the same reference numeral labels.

[0009] FIG. 1 A - schematically depicts a spacer of one wire or rod.

[0010] FIG. IB - schematically depicts a common spacer from mesh.

[0011] FIG. 1C - schematically depicts a second common spacer from mesh.

[0012] FIGS. ID - IE - depict spacers of mesh with more than two longitudinal wires.

[0013] FIGS. IF - 1G - depict spacers with variant formation of the apexes.

[0014] FIGS. 1H - II - depict spacers from mesh and having differing length sides.

[0015] FIG. 2A - a schematic side view at the beginning of method operations.

[0016] FIG. 2B - a schematic side view of progress of method operations.

[0017] FIG. 3 - a detailed perspective view of a system for production of spacers.

DESCRIPTION

[0018] In following are presented descriptions of exemplary implementations of systems and methods in the sense of non-limiting examples.

[0019] The spacers 2 are depicted in FIGS. 1A-1I and may be of differing forms. FIG. 1A depicts a spacer 2 comprised of one wire or rod. In contrast, FIG. IB depicts the most common type of spacer 2, that includes a longitudinal mesh with two longitudinal wires. FIG. 1C similarly depicts a spacer 2, but in a version with the transverse wires located between the longitudinal wires rather than below as depicted in FIG. IB. FIGS. ID and IE depict corresponding spacers to those of FIGS. 1B-1C, but including more longitudinals, as indicated. FIGS. IF and 1G present spacers 2 with differing formation of the apexes. Finally, FIGS. 1H and II present spacers with different length sides, as can be seen from side view.

[0020] A method may be understood in an exemplary sense for the production of a spacer 2 with five horizontal sections, for example as in FIGS. IB - 1C. It should be understood that, with the same method, there may be produced spacers with more or fewer horizontal sections.

[0021] Considering FIGS. 1B-1C and FIG. 2B, spacer 2 includes straight sections A'B', B'C, CD', D'E', E'F', F'G', G'FT, HT, IT, J'K' and K'L' of which B'C, D'E', F'G', H'J', and J'K' are horizontal, as depicted. The location O' coincides with the middle of the straight section F'G'. With further reference to FIG. 2 A, the spacer 2 is produced from the starting mesh 1 on which may be identified the locations A, B, C, D, E, F, G, H, I, J, K, L that correspond to locations A, B', C, D', E', F', G', FT, Γ, J', K', L' of the formed spacer 2.

[0022] At the location O of the under- formation mesh 1 there is located a gripper 3 that is fixed and holds the product 1 along length FG. A second gripper 4 holds the under- formation mesh 1 on the straight section DE. The gripper 4 is seated upon guides 9 and with the action of a force originating for example from a cylinder 22 may transpose the section DE perpendicular relative to axis XX'. Carrier 8 of gripper 4 and the guides 9 upon which gripper 4 moves are seated on a plate carrier 14 which is moved on guides 30 along the length of axis XX'. [0023] A third gripper 6 restrains the subject-to-formation mesh 1 on the straight section BC. The gripper 6 is seated on carrier 16 that moves on guides 30 along the length of axis XX'. On this carrier 16 there is seated a bending mechanism 81 that rotates a tool 31 around its axis by the action of a force that originates for example from a cylinder 24.

[0024] Considering the other direction along axis XX' from location O, on the straight section HI acts gripper 5 that is seated on a carrier 11 that is moved on guides 12 perpendicularly relative to axis XX', which carrier 11 is moved by a force exercised, for example, by cylinder 23. Gripper 5, carrier 11, guides 12 and cylinder 23 are seated on plate carrier 15 that is seated on the guides 30 and is moved parallel to axis XX'.

[0025] On the straight section JK acts gripper 7 seated on carrier 17 that in turn moves on guides 30 parallel to axis XX'. On this carrier 17 there is seated a bending mechanism 82 that rotates the tool 32 on its axis by the action of a force originating from a cylinder 25.

[0026] An exemplary method and system operate as follows. The grippers 3, 4, 5, 6, 7 are located at their initial locations that correspond to straight sections FG, DE, HI, BC, JK. The under- formation mesh 1 is placed on axis XX' and inside the grippers. The grippers are energized and squeeze the under-formation product at the referred-to corresponding straight sections. Subsequently there are energized the respective cylinders 22, 23 on the respective carriers 14, 15 correspondingly. The straight section DE is transposed towards the D'E' and the HI towards the HT. During the movement of carriers 8, 11

perpendicularly relative to axis XX' there are moved the carriers 14, 15, 16, 17 parallel with the axis XX', because the carriers are linked via the intermediate longitudinal wires of the product. For example, the intermediate section EF carries the gripper 4, the straight section DE and the carrier 14 on the guides 30 along the length of axis XX'.

Simultaneously via the action of straight section CD the gripper 6, the straight section BC, and the carrier 16 are transferred on guides 30 along the length of axis XX'.

[0027] With the completion of the action of the cylinders 22, 23 the initial product is formed into a spacer 2. The end sides AB and KL are bent with the action of bending mechanisms 81, 82 correspondingly either at the beginning, the duration or the end of the deformation.

[0028] With the retraction of the forces of cylinders 22, 23 the longitudinal wires of the product undergo elastic recovery and the product 2 with the carriers steadies in its final form. This elastic recovery is a combination of the diameter, the mechanical properties of the material and the geometry of the shape. By deforming towards the appropriate size more than desired, with this elastic recovery there is obtained the desired geometry.

Subsequently, the grippers 3, 4, 5, 6, 7 may be opened and the product is then rendered towards a storage.

[0029] Considering FIGS. IF- II, the restraining tools at the gripper may be formed at their interior side with a radius of curvature so as to correspond to the desired radius of curvature of the longitudinal wires of the spacer 2.

[0030] The method was presented in exemplary form for the products of FIGS. 1A-1I. It should be understood that the method may be applied for the simultaneous formation of spacers 2 with either more or fewer apexes. Furthermore, while the method is

advantageously applied for the production of spacers from initial product mesh, it should be understood that it may in this form also deform at least one or more wires or rods, as depicted in FIGS. 1A, IF.

[0031] According to the method, the form of the spacer 2 depends on the tools on the grippers. With different tools a different product may be produced, such as, for example, the products of FIGS. lF-lG. Furthermore, with more particular reference to FIG. II, according to the method, it should be understood that the apexes of the spacer may have either the same or different forms in correspondence with the chosen tools on the grippers. Again with reference to FIGS. 1H-1I, according to the method, the sections on the apexes F'G', D'E', B'C, HT, J'K' may have either equal or different lengths.

[0032] With further reference to FIG. 1H , according to the method the intermediate sections EF and CD may be different or equal length one to the other. With the action of the forces, the carriers are moved and deform the product.

[0033] Accordingly, FIGS. 2A-2B indicate in an exemplary manner methods for production of spacers 2 from mesh, wires or rods or material of prismatic cross section 1, which spacers 2 include inclined sections A'B', CD', E'F', G'FT, IT, K'L' with alternating inclinations and intermediate apexes B'C, D'E', F'G', HT, J'K'. As explained, the starting product 1 is restrained at a location O by gripper 3, and an apex DE beside location O is restrained by a gripper 4 that is seated on guides 9 so as to be movable by the action of a force perpendicular to the longitudinal direction of product XX'. The guides 9, after the gripper 4, are ultimately seated on guides 30 so that they may move along the length of direction XX'. The subsequent apex BC is restrained by a gripper 6 that is seated on carrier 16, and this carrier 16 on guides 30 so as to be movable in the direction XX'. On the gripper 6 there is seated a rotating bending mechanism 81 that bends the last section A'B' of the spacer 2. Advantageously, from the other side of location O there are grippers 5, 7 and carriers 11, 17 with the same functionality and aim, with the starting mesh 1 being positioned inside the grippers 3, 4, 5, 6, 7. The sum of the grippers 3, 4, 5, 6, 7 restrain the subject-to-formation material 1. By the action of cylinders 22, 23 respectively on the carriers of grippers 4, 5 the starting material 1 is deformed into the form of a spacer 2, with the carriers 14, 15, 16, 17 being pulled by the inclined sections CD', E'F', G'FT, I'J'of the product. The rotating bending mechanisms 81, 82 bend the endmost sections A'B', K'L' of the spacer 2 to a desired angle. The conclusion of formation ends the action of formation forces of respective cylinders 22, 23 of carriers 14, 15 and the formed product 2 may undergo elastic recovery and thus assume its final form. At the end, the grippers 3, 4, 5, 6, 7 open to deliver product 2.

[0034] In following to the explanation of the immediately preceding paragraph, and with reference to FIGS. IF - II, it should be understood that optionally, the form of the product at the apexes may be of any form, in conjunction with the form of the restraining tools of the grippers 3, 4, 5, 6, 7. Again in following to the explanation of the immediately preceding paragraph, optionally the product may be made up of identically or differently inclined sides.

[0035] Considering FIG. 2 A and FIG. 3, the central jaw 3 has situated both a stationary tool 41 and also a movable tool 42 that is moved by the air cylinder 40. The gripper 3 has a slot disposed so that it may enter inside the under-production mesh 1 in a manner that may be understood from FIG. 3. [0036] As may be further understood from FIG. 2A and FIG. 3, the grippers 4, 5 also each dispose a respective stationary 41 and a respective movable tool 42 which by the action of respective cylinders 40 hold the under- formation mesh 1. The gripper 4 is seated on respective carrier 8 that is moved by the action of respective air cylinder 22 on guides 9 perpendicular to the under- formation mesh 1. The guides 9 are seated on a plate carrier 14 that in turn is seated on guides 30 so as to be movable parallel to the longitudinal axis XX' of the product. Air cylinder 71 acts on plate carrier 14, functioning to return the plate carrier 14 to its starting position for the start of formation, while during the duration of formation the cylinder 71 does not exert forces on the plate carrier 14.

[0037] Considering FIG. 2 A and FIG. 3 further, the gripper 6 has the same form with the gripper 7 and is located on respective carrier 16 that is seated upon guides 30. The gripper 6 also has disposed a stationary 41 tool and a movable tool 42, and these by action of cylinders 40 restrain the under- formation mesh 1. On gripper 6 is seated a rotating bending mechanism 81, that includes the movable tool, being in this example the cylinder 31 seated on a lever and being movable by air cylinder 24. As shown, the air cylinder 72 acts on carrier 16 so as to transport it to its initial location for the start of deformation, while during the duration of deformation it does not exert forces upon carrier 16. [0038] On the other side of location O and symmetrically relative to the machine axis

XX', there are respective grippers 5, 7 with corresponding functions to those of grippers 4, 6, and there is also a bending mechanism 82 in correspondence to bending mechanism 81.

[0039] As depicted in detail in FIG. 3, the sum of the grippers 3, 4, 5, 6, 7 the carriers 13, 16, 17, 8, 11 and the guides 30 mount on a plate 59 and rotating beam 60. The rotating beam 60 is seated on two respective axes 64 of the respective thrust bearings 61 on the frame 62 of the machine. With the action of air cylinders 63 the mechanism assembly of the grippers may assume two positions, one horizontal for the supply of starting mesh 1 , depicted in FIG. 3, and one rotated, at an apex at which the unloading of the produced spacer 2 occurs.

[0040] The function of this exemplary machine of FIG. 3 may be understood as follows. Initially, the machine is found at a horizontal position and all the grippers 3, 4, 5, 6, 7 at their initial locations after their spacers. The under-formation initial product 1 is advanced inside grippers 3, 4, 5, 6, 7. These grippers 3, 4, 5, 6, 7 squeeze the under-formation product 1 with the action of respective cylinders 40. In following, the respective air cylinders 22, 23 of grippers 4, 5 respectively, are energized. Simultaneously, with the action of cylinders 22, 23 carriers 14, 15, 16, 17 are moved. Simultaneously, respective cylinders 24, 25 of the respective rotatable bending mechanisms 81, 82 are energized for the formation of the external sides. Consideration of FIG. 2B indicates the effect. With the end of formation the air cylinders 22, 23 are deenergized and the carriers are transposed anew because of the elastic recovery.

[0041] Then in progress toward finishing, the gripper system rotates to the unloading position (apex) under the action of cylinders 63. At the unloading position grippers 3, 4, 5, 6, 7 are deenergized and the readied product 2 falls to a collection surface where it is received.

[0042] It should be understood by the above discussion that the system may produce spacers 2 with manual feeding of meshes 1 , or the system may be supplied with meshes 1 from a mesh storage via a suitable supply mechanism. Furthermore, the system may cooperate with a production machine for meshes 1 , these produced meshes then being automatically fed and the synchronization being effected by a central control unit.

[0043] Accordingly, FIGS. 2A-2B and FIG. 3 indicate in an exemplary manner systems for production of spacers 2 from mesh, wires or rods 1, which spacers 2 have inclined sections A'B', CD', E'F', G'FT, IT, K'L' with alternating inclinations. The starting product 1 is restrained at location O by gripper 3 with the action of cylinders 40, and beside location O there is gripper 4 energized by another cylinder 40, that restrains the mesh 1 at a starting location that, after the formation corresponds to the next neighboring apex D'E' of the spacer 2. The gripper 4 is seated on a respective carrier 8 which is ultimately seated on guides 9 so as to be moved by the action of cylinder 22 perpendicular to the longitudinal direction XX' of product. The carrier 8 is seated on guides 30 via plate carrier 14 so as to be able to move along the length of direction XX'. In following, in the same direction there is a jaw 6 that also restrains the starting mesh 1 at a location BC that corresponds to the next apex B'C, with the gripper 6 being energized by cylinders 40 and the gripper 6 being seated on carrier 16 and thus on guides 30 so as to be able to be moved parallel to the direction XX'. On the gripper 6 there is seated a rotating bending mechanism 81 that by action of cylinder 24 bends the end section A'B' of the spacer 2. On the other side of location O there exist the same grippers 5,7 and the same carriers 11, 15, 17 with the same functionality and aim. The cylinders 71, 72, 73, 74 act to transfer, correspondingly, the respective carriers 14, 16, 15, 17 to their respective starting locations, as they do not typically exert any significant force on the carriers during the duration of formation. The entire gripper mechanism assembly is advantageously supported on a rotating beam 60, and this rotating beam in turn is supported upon two bearings 61 in a metallic construction frame 62. This rotating beam 60 rotates by the action of two cylinders 63, taking two positions, one horizontal for supply of the starting mesh 1 and one apex position for the unloading of the formed product 2. The starting mesh 1 is positioned symmetrically in the jaws 3, 4, 5, 6, 7 and these jaws 3, 4, 5, 6, 7 are located at the appropriate positions along axis XX' by the action of cylinders 71, 72, 73, 74. In following, the grippers 3, 4, 5, 6, 7 restrain the subject-to-formation mesh 1, cylinders 22, 23 are energized, and the starting mesh 1 is formed into the spacer 2, with the carriers 14, 15, 16, 17 being pulled by the inclined sections CD', E'F', G'H', IT of the product 2. Simultaneously, the rotating bending mechanisms 81, 82 bend the end sections A'B', K'L' of the spacer 2 to a desired angle. With the conclusion of formation ends the action of the deformation forces of cylinders 22, 23 of plate carriers 14, 15, and the formed product 2 undergoes elastic recovery and takes its final form. To finish, the entire gripper system rotates to an apex location by the action of cylinders 63, and the restraining cylinders 40 of all the grippers are deenergized to deliver the formed spacer 2.

[0044] In following to the explanation of the immediately preceding paragraph, it should be understood that optionally, the feeding of meshes 1 may be made automatically by a machine for the production of mesh, or may be made automatically by a feeder. Systems according to the explanation of the immediately preceding paragraph may optionally but preferably be controlled by an electronic computer so that all the working phases occur automatically. [0045] It should be understood in the context of the preceding discussion that the present invention is not limited in any manner to the described and drawings-depicted

implementations, but may be realized in many forms and dimensions without abandoning the region of protection of the invention. For example, in implementations of the invention the materials that are used and also as well the dimensions of particular elements may be according to the demands of a particular construction. Thus, in closing, it should be noted that the invention is not limited to the abovementioned versions and exemplary working examples. Further developments, modifications and combinations are also within the scope of the patent claims and are placed in the possession of the person skilled in the art from the above disclosure. Accordingly, the techniques and structures described and illustrated herein should be understood to be illustrative and exemplary, and not necessarily limiting upon the scope of the present invention. The scope of the present invention is defined by the appended claims, including known equivalents and

unforeseeable equivalents at the time of filing of this application.

[0046] REFERENCE SIGNS LIST

1 starting (initial) mesh

2 spacer

3,4,5,6,7 grippers (jaws)

8 carrier of gripper 4

9 guides

11 carrier of gripper 5

12 guides

13 carrier of gripper 3

14 plate carrier

15 plate carrier

16 carrier of gripper 6

17 carrier of gripper 7

22 cylinder

23,24,25 cylinders

30 guides 31,32 bending tool

40 air cylinders

41 stationary tool of jaw

42 movable tool of jaw

59 plate

60 rotating beam

61 thrust bearings

62 frame of machine

63 air cylinders

64 axes of thrust bearings 61

71,72,73,74 air cylinders

81, 82 bending mechanisms

A- L locations on mesh

A' - L' locations on spacer 2

XX' longitudinal axis

Ο, Ο' location (central)