Machine for manufacturing flanges of electrical cable reels by nailing pieces of wood

Abstract

 A machine for manufacturing flanges of electrical cable reels by nailing pieces of wood, comprising a main supporting structure (2), which supports a worktable (3) which is designed to support the pieces of wood (4) to be joined by nailing, the machine comprising compaction means (8), which can engage the pieces of wood (4) deposited on the worktable (3), and means (9) for turning the pieces of wood (4), which are arranged on the worktable (3), about an axis which is substantially perpendicular to the worktable and coincides with the axis of the flange (40) to be provided; at least one bar (5b) is arranged above the worktable (3) and supports nailing clamps (6), which face the worktable (3) and can be actuated in order to nail together the pieces of wood (4), compaction means (8) being provided which are arranged and supported externally with respect to the region that lies above the worktable (3) and is occupied by the pieces of wood (4) of the flange (40) that are subjected to nailing and by the nailing clamps (6).

Description

[0001] The present invention relates to a machine for manufacturing flanges of electrical cable reels by nailing pieces of wood.

[0002] As is known, electrical cable reels are generally constituted by a substantially cylindrical wooden core which has, at each end, a flange usually manufactured by superimposing and nailing two layers of pieces of wood so that the pieces of one layer lie substantially at right angles to the pieces of the other layer.

[0003] In order to achieve an adequate strength of the flanges, it is necessary to perform a large number of nailing operations for assembling the wooden pieces; these nailing operations are performed along concentric circles around the axis of the flange with preset distances between the circles and between the nailing points on a same circle.

[0004] Nailing for assembling the pieces of wood which compose reel flanges is performed by using nailing machines, generally constituted by a main supporting structure, which has a substantially horizontal worktable on which the two layers of wooden pieces, which compose the flange and are designed to be nailed, are deposited. Such machines are provided with compaction means and rotation means, which can be operated in order to keep the wooden pieces together during nailing and in order to cause their intermittent rotation about a vertical axis, which coincides with the axis of the flange, between the various nailing operations for assembly that are to be performed.

[0005] Above the worktable, the main supporting structure supports a first substantially horizontal bar, which supports the nailing plungers or hammers, which protrude downwardly from the first bar toward the worktable. A second bar is interposed between the first bar and the worktable, is substantially parallel to the first bar, and supports one or more parallel rows of nailing clamps.

[0006] Each nailing clamp is crossed by a substantially vertical nailing channel, which is open at the top and at the bottom and is connected to a lateral feed duct, through which a nail is introduced in the nailing channel in each instance. The nailing clamps are provided so that the last portion of the nailing channel, which lies closest to the underlying worktable, can widen in order to allow the passage of the head of the nail during the nailing operation.

[0007] For each nailing channel a nailing plunger is provided, which is supported by the overlying first bar, and the first bar can move with respect to the second bar along a vertical direction in order to cause the advancement, during its motion toward the worktable, of the nailing plungers in the corresponding nailing channel of the nailing clamps and produce the expulsion of the nail, which is located in said channel, toward the worktable and in order to move the nailing plungers, during its motion away from the worktable, above the outlet of the feed duct in the corresponding nailing channel in order to allow the descent, into the nailing channel, of a new nail to be used in the subsequent nailing operation.

[0008] The second bar also can move vertically in order to place, by way of its descent toward the worktable, the nailing clamps in contact, by means of their lower end in which the outlet of the nailing channel is provided, with the wooden pieces to be nailed or in order to disengage, with its upward motion, the nailing clamps from the pieces, which during the disengagement from the clamps are turned about a vertical axis, which coincides with the axis of the flange, in order to prepare them for the subsequent nailing operation.

[0009] In semiautomatic machines, the compaction means are constituted simply by presses or clamps which, after being filled with the wooden pieces which constitute the flange, are closed manually and turned about the flange axis, again manually, in order to bring the flange to the various nailing positions.

[0010] In automatic machines, the compaction means comprise a plurality of arms which protrude from a central support, which is arranged above the worktable and is axially aligned with the axis of the flange about which such flange must be turned in order to be placed in the various nailing positions. Such arms are provided, proximate to their end which lies opposite the central support, with grip elements which are actuated pneumatically and can engage the edges of the flange in order to clamp the pieces of wood together, so as to reduce as much as possible the play among the various pieces.

[0011] The rotation of the wooden pieces about the axis of the flange in order to place the flange in the various nailing positions is performed by way of the rotation means, constituted by a rotating element which is arranged on the worktable and can engage a central region of the lower face of the flange.

[0012] In such automatic machines, because the arms that support the grip elements are located above the flange, during the rotation of the flange being nailed, the compaction means can interfere with the nailing clamps, limiting the possibility of rotation of the flange if the grip elements are kept engaged with the pieces of wood and therefore rotate with them.

[0013] For this reason, the grip elements are kept engaged with the wooden pieces of the flange only through a limited arc of rotation. The dimensions of the arms that support the grip elements, in known types of nailing machines, and the position of the nailing clamps are studied so as to allow to keep the grip elements engaged with the flange in performing a number of nailing operations which is limited but is such as to keep the pieces of wood that compose the flange correctly joined. After this limited number of nailing operations, the grip elements are disengaged from the flange so that the compaction means are no longer entrained by the rotation imparted to the flange, which continues to be turned about its own axis until the nailing operation is completed.

[0014] In automatic machines of this kind, the need is felt to increase the number of nailing clamps so as to increase the speed of the nailing operation and therefore increase the productivity of these machines.

[0015] However, this need clashes with the need to keep the compaction means engaged with the flange during the execution of a minimum number of nailing operations which is sufficient to prevent the pieces from moving undesirably when the compaction means must be disengaged from the flange in order to complete the nailing operation. The increase in the number of nailing clamps in fact reduces the rotation arc of the flange through which the compaction means can be kept engaged with the pieces of wood.

[0016] The aim of the present invention is to solve the problem described above by providing a machine for manufacturing flanges of electrical cable reels by nailing pieces of wood, in which the presence of the compaction means does not limit the possibility of rotation of the flange about its own axis during nailing.

[0017] Within this aim, an object of the invention is to provide a machine in which the compaction means can be kept engaged with the flange through an arc of rotation which is greater than the arc allowed by conventional machines or even through the entire rotation of the flange required to complete the nailing operation.

[0018] Another object of the invention is to provide a machine in which it is possible to increase freely the number of nailing clamps in order to increase the productivity of the machine.

[0019] Another object of the invention is to provide a machine which offers the greatest assurances of reliability and safety in use.

[0020] This aim and these and other objects, which will become better apparent hereinafter, are achieved by a machine for manufacturing flanges of electrical cable reels by nailing pieces of wood, comprising:

• a main supporting structure, which supports a worktable which is designed to support the pieces of wood to be joined by nailing;
• compaction means, which can engage the pieces of wood deposited on said worktable;
• means for turning said pieces of wood, which are arranged on said worktable, about an axis which is substantially perpendicular to said worktable and coincides with the axis of the flange to be provided;
• at least one bar, which supports nailing clamps which face said worktable and can be actuated in order to nail together said pieces of wood;

characterized in that said compaction means are arranged and supported externally with respect to the region that lies above the worktable and is occupied by the pieces of wood of the flange that are subjected to nailing and by said nailing clamps.

[0021] Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of the machine according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a schematic sectional front view of the machine according to the invention, taken along a front vertical plane which passes through the axis of the flange being nailed;

Figure 2 is a schematic sectional view of Figure 1, taken along the line II-II;

Figure 3 is a schematic sectional view of the machine, taken in a manner similar to Figure 2, with some parts shown in cutout view and with some elements of the machine omitted for the sake of greater clarity;

Figure 4 is a schematic and partially sectional side elevation view of the machine;

Figure 5 is an enlarged-scale view of a detail of Figures 2 and 3;

Figure 6 is an enlarged-scale sectional view of a detail of Figure 1, taken along the line VI-VI;

Figure 7 is an enlarged-scale sectional view of a detail of Figure 3, taken along the line VII-VII;

Figure 8 is an enlarged-scale view of a detail of Figure 1;

Figure 9 is an enlarged-scale sectional view of a detail of Figure 2, taken along the line IX-IX;

Figure 10 is an enlarged-scale sectional view of another detail of Figure 2, taken along the line X-X.

[0022] With reference to the figures, the machine according to the invention, generally designated by the reference numeral 1, comprises a main supporting structure 2, which supports a substantially horizontal worktable 3, on which the pieces of wood 4 are designed to be arranged, in a per se known manner, i.e., in two superimposed horizontal layers in which the pieces 4 of one layer are oriented at right angles to the pieces of the other layer, which must be nailed in order to obtain the flange 40 to be manufactured.

[0023] Above the worktable 3, the main supporting structure 2 supports at least one substantially horizontal bar 5b, which supports nailing clamps 6, which face the worktable 3 and can be actuated in a per se known manner in order to nail the pieces 4 arranged on the worktable 3.

[0024] More specifically, above the worktable 3 the main supporting structure 2 supports two bars: of which, a first substantially horizontal bar 5a, which supports the nailing plungers or hammers 7, which protrude downwardly from the first bar 5a toward the worktable 3. A second bar 5b is interposed between the first bar 5a and the worktable 3 and is substantially parallel to the first bar 5a and supports one or more parallel rows of nailing clamps 6.

[0025] Each nailing clamp 6 is crossed by a substantially vertical nailing channel, which is open at the top and at the bottom and is connected to a lateral feed duct, through which a nail is introduced in the nailing channel in each instance. The nailing clamps 6 are provided so that the last portion of the nailing channel, which lies closest to the underlying worktable 3, can widen in order to allow the head of the nail to pass during the nailing operation.

[0026] For each nailing channel a nailing plunger 7 is provided, which is supported by the overlying first bar 5a, and the first bar 5a can move with respect to the second bar 5b along a vertical direction in order to cause the advancement, during its motion toward the worktable 3, of the nailing plungers 7 in the corresponding nailing channel of the nailing clamps 6 and produce the expulsion of the nail, which is located in said channel, toward the worktable 3 and in order to move the nailing plungers 7, during its motion away from the worktable 3, above the outlet of the feed duct in the corresponding nailing channel in order to allow the descent into the nailing channel of a new nail to be used in the subsequent nailing operation.

[0027] The second bar 5b also can move vertically in order to arrange, with its descent toward the worktable 3, the nailing clamps 6 so that they make contact by means of their lower end, in which the outlet of the nailing channel is formed, with the pieces 4 to be nailed or so as to disengage, with its upward motion, the nailing clamps 6 from the pieces 4.

[0028] The actuation of the first bar 5a and of the second bar 5b in order to nail the pieces of wood 4 deposited on the worktable 3 can be performed in a conventional manner or as disclosed in Italian Patent Application MI2004A-002392 by the same Applicant.

[0029] The machine comprises compaction means 8, which can engage the pieces of wood 4 deposited on the worktable 3, and means 9 for turning such pieces of wood 4 about an axis 10 which is perpendicular to the worktable 3 and coincides with the axis of the flange 40 to be manufactured.

[0030] According to the invention, the compaction means 8 are arranged and supported externally with respect to the region that lies above the worktable 3, which is occupied by the pieces of wood 4 of the flange 40 to be produced and by the nailing clamps 6. In this manner, the compaction means 8 cannot interfere in any way with the nailing clamps 6 during the rotation of the pieces of wood 4 performed by the rotation means 9, and the number of nailing clamps 6 can be increased with no problem so as to achieve, for the machine according to the invention, a productivity which is higher than that achievable with known types of machines.

[0031] Conveniently, the compaction means 8 comprise at least one pair of pressers 11a, 11b, 12a, 12b, which are opposite one another and can move on command toward or away from each other so as to engage or disengage respective diametrically mutually opposite regions of the flange 40 being nailed and composed of the pieces of wood 4.

[0032] Preferably, the compaction means 8 comprise two pairs of pressers 11 a, 11b, 12a, 12b which are opposite one another and are arranged so as to engage two pairs of mutually diametrically opposite regions of the flange 40, which are mutually offset substantially through 90° about the axis 10 of the flange 40.

[0033] The pressers 11a, 11b, 12a, 12b are each mounted on a supporting arm 13a, 13b, 14a, 14b, connected to a center bearing 15, which is arranged on a substantially horizontal plane above the worktable 3. The center bearing 15 is coaxial to the flange 40 being nailed and lies externally around the region of the worktable 3 which is designed to support the pieces of wood 4 of the flange being nailed. The diameter of the center bearing 15 is greater than the diameter of the biggest flange 40 that can be manufactured with the machine according to the invention.

[0034] Each supporting arm 13a, 13b, 14a, 14b is arranged along a chord of the center bearing 15, and the supporting arms, on which pressers 11 a, 11b, 12a, 12b are arranged in mutually opposite positions, are substantially parallel to each other.

[0035] Each supporting arm 13a, 13b, 14a, 14b has a variable length and its ends are connected to the center bearing 15 in connecting regions which can be changed in order to vary the distance of the pressers from the axis 10 of the center bearing 15 depending on the dimensions of the flange 40 being nailed.

[0036] These connection regions are formed by curved slots 16, 17, which are formed in the center bearing 15 and are coaxial to said center bearing 15. The ends of the supporting arms 13a, 13b, 14a, 14b are bolted in said slots 16, 17, in regions which can change according to the requirements.

[0037] The variability of the length of each individual supporting arm 13a, 13b, 14a, 14b, in order to adapt it to the length of the chord of the center bearing 15 along which the supporting arm is arranged depending on the dimensions of the flange 40 being nailed, is achieved by providing each supporting arm 13a, 13b, 14a, 14b in three parts: respectively, a central part 18a, 18b, 19a, 19b and two rods 18a', 18a", 18b', 18b", 19a', 19a", 19b', 19b", which lie on horizontal planes at mutually different heights and are arranged along the same direction. The two rods 18a', 18a", 18b', 18b", 19a', 19a", 19b', 19b" of each supporting arm can slide with respect to the central part 18a, 18b, 19a, 19b indeed in order to vary the total length of the supporting arm 13a, 13b, 14a, 14b.

[0038] It should be noted that the arrangement of the rods of the various supporting arms 13a, 13b, 14a, 14b is such as to avoid interference between contiguous supporting arms and obtain a substantially coplanar situation for the central part 18a, 18b, 19a, 19b.

[0039] The pressers 11a, 11b, 12a, 12b are connected to the lower side of the central part 18a, 18b, 19a, 19b of each supporting arm 13a, 13b, 14a, 14b and each one is constituted by a plate, which is arranged on a vertical plane and is supported slidingly by the corresponding central part 18a, 18b, 19a, 19b along a horizontal direction which is perpendicular to the extension of the arm 13a, 13b, 14a, 14b that supports it.

[0040] The sliding of each presser 11a, 11b, 12a, 12b with respect to the arm 13a, 13b, 14a, 14b that supports it is achieved preferably by means of a fluid-operated cylinder 20a, 20b, 2 1 a, 21b, which is mounted on the central part 18a, 18b, 19a, 19b of the corresponding supporting arm 13a, 13b, 14a, 14b and is connected to said plate by means of the stem of its piston.

[0041] The center bearing 15 is supported, so that it can rotate about its own axis, by the main supporting structure 2 and the rotation means 9 comprise means for actuating the center bearing 15 with an intermittent motion about its own axis 10 with respect to the main supporting structure 2.

[0042] More particularly, the center bearing 15 is supported by a quadrangular framework 22, which is arranged on a substantially horizontal plane. The framework 22 supports the center bearing 15 by means of three sets of cylindrical bearings, each set being formed by: a lower bearing 23, on which the lower face of the center bearing 15 rests; an upper bearing 24, which rests against the upper face of the center bearing 15; and a lateral bearing 25, which rests against the lateral edge of the center bearing 15. The axes of the lower bearing 23 and of the upper bearing 24 are oriented radially with respect to the center bearing 15, while the axis of the lateral bearing 25 is oriented vertically. In this manner, the center bearing 15 is firmly anchored to the framework 22 although it can rotate about its own axis 10 with respect to said framework 22.

[0043] The means for actuating the center bearing 15 with an intermittent motion about its axis 10 comprise a gearmotor 26, which is mounted on the framework 20 and is connected, by means of its output shaft, to the center bearing 15. More particularly, a pinion 27 is keyed to the output shaft of said gearmotor 26 and meshes with a chain 28, which surrounds the center bearing 15 and is fixed thereto at a point 29. In this manner, by actuating the gearmotor 26 it is possible to achieve the rotation of the center bearing 15 about its own axis 10 with respect to the framework 22 through an arc of at least 180°, which allows to perform the entire nailing of the flange 40.

[0044] The framework 22 is supported by the main supporting structure 2 so that it can slide along a vertical direction, and means for translational motion are provided which act on the framework 22 in order to move it vertically, so as to lift or lower the center bearing 15 with respect to the worktable 3.

[0045] More particularly, the main supporting structure 2 is provided with two vertical shoulders 30a, 30b, to which guiding plates 31a, 31b are fixed; side walls 32a, 32b fixed laterally to the framework 22 mate with the said plates.

[0046] The means for translational motion comprise a shaft 33, which is arranged horizontally and is supported, so that it can rotate about its own axis, by the main supporting structure 2. Two gears 34a, 34b are keyed on said shaft 33, which can be turned about its own axis by means of a known type of gearmotor, not shown for the sake of simplicity; said gears mesh with respective racks 35a, 35b, which are arranged vertically and are supported so that they can slide along their extension by the main supporting structure 2. These racks 35a, 35b, by means of rods 36a, 36b, are connected to the framework 22 so that an actuation of the shaft 33 with a rotary motion about its own axis in one direction or in the opposite direction causes an upward or downward translational motion of the framework 22.

[0047] Operation of the machine according to the invention is as follows.

[0048] With the framework 22 that supports the center bearing 15 in a position which is spaced above the worktable 3, the pieces of wood 4 are deposited on the worktable 3 in two superimposed layers, which are offset in a per se known manner and must be nailed in order to produce the flange 40.

[0049] By actuating the shaft 33, the framework 22 is lowered and therefore the center bearing 15 is lowered toward the worktable 3, so that the pressers 11a, 11b, 12a, 12b face the perimetric edge of the two layers of pieces of wood 4 to be nailed, which are deposited on the worktable 3.

[0050] At this point, the fluid-operated cylinders 20a, 20b, 21a, 21b are actuated and push the pressers 11 a, 11b, 12a, 12b against the pieces of wood 4, compacting them.

[0051] The nailing clamps 6 are then actuated and cyclically perform a nailing operation and are then raised above the flange 40 being produced. While the nailing clamps 6 are disengaged from the flange 40, the gearmotor 26 is actuated so as to produce the rotation, through a preset angle, of the center bearing 15 and therefore of the flange 40 being nailed, about the axis 10 of said flange 40 with respect to the main supporting structure 2 and therefore with respect to the nailing clamps 6, so as to preset the flange 40 for the subsequent nailing operation.

[0052] By proceeding in this manner, the nailing operation of the flange 40 is completed. It should be noted that the rotation of the bearing 15 about its own axis 10 throughout the nailing operation can be performed without disengaging the presser elements 11a, 11b, 12a, 12b from the flange 40, since the particular arrangement of the compaction means 8 in the machine according to the invention excludes any possibility of interference of the compaction means 8 with the nailing clamps 6 even if a large number of nailing clamps 6 is mounted on the machine due to production requirements.

[0053] At the end of the nailing process, the pressers 11a, 11b, 12a, 12b are disengaged from the flange 40 and the center bearing 15 is again raised above the worktable 3 in order to allow the manufactured flange 40 to move away and allow the deposition of pieces of wood 4 on the worktable 3 in order to manufacture a new flange.

[0054] In practice it has been found that the machine according to the invention fully achieves the intended aim, since the particular arrangement of the compaction means safely avoids interference between the compaction means and the nailing clamps, allowing to mount on the machine a large number of nailing clamps in order to achieve high productivity.

[0055] The machine thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; all the details may further be replaced with other technically equivalent elements.

[0056] In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.

[0057] The disclosures in Italian Patent Application No. MI2005A000743 from which this application claims priority are incorporated herein by reference.

[0058] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A machine for manufacturing flanges of electrical cable reels by nailing pieces of wood, comprising:

- a main supporting structure (2), which supports a worktable (3) which is designed to support the pieces of wood (4) to be joined by nailing;

- compaction means (8), which can engage the pieces of wood (4) deposited on said worktable (3);

- means (9) for turning said pieces of wood (4), which are arranged on said worktable (3), about an axis (10) which is substantially perpendicular to said worktable (3) and coincides with the axis of the flange (40) to be manufactured;

- at least one bar (5b), which supports nailing clamps (6) which face said worktable (3) and can be actuated in order to nail together said pieces of wood (4);

characterized in that said compaction means (8) are arranged and supported externally with respect to the region that lies above the worktable (3) and is occupied by the pieces of wood (4) of the flange (40) that are subjected to nailing and by said nailing clamps (6).

2. The machine according to claim 1, characterized in that said compaction means (8) comprise at least one pair of mutually opposite pressers (11a, 11b, 12a, 12b), which can move on command toward or away from each other in order to engage or disengage with respect to a pair of mutually diametrically opposite regions of the flange (40) to be nailed, which is composed of said pieces of wood (4).

3. The machine according to claims 1 and 2, characterized in that said compaction means (8) comprise two pairs of mutually opposite pressers (11a, 11b, 12a, 12b), which can move on command toward or away from each other in order to engage or disengage with respect to two pairs of mutually diametrically opposite regions of the flange (40) to be nailed, which is composed of said pieces of wood (4), said two pairs of mutually diametrically opposite regions being mutually offset by substantially 90° about the axis (10) of the flange (40).

4. The machine according to one or more of the preceding claims, characterized in that said pressers (11a, 11b, 12a, 12b) are each mounted on a supporting arm (13a, 13b, 14a, 14b), which is connected to a center bearing (15) which lies on a substantially horizontal plane above said worktable (3) and coaxially to the flange (40) to be nailed.

5. The machine according to one or more of the preceding claims, characterized in that said center bearing (15) is arranged externally around the region of said worktable (3) which is designed to support the pieces of wood (4) of the flange (40) being nailed, the diameter of said center bearing (15) being greater than the maximum diameter of the flange (40) which can be manufactured on the machine.

6. The machine according to one or more of the preceding claims, characterized in that the supporting arms (13a, 13b, 14a, 14b) of said pressers (11a, 11b, 12a, 12b) are arranged along chords of said center bearing (15), the supporting arms that support the mutually opposite pressers (11a, 11b, 12a, 12b) being substantially parallel to each other.

7. The machine according to one or more of the preceding claims, characterized in that said supporting arms (13a, 13b, 14a, 14b) have a variable length and their ends are connected to said center bearing (15) in connection regions which can vary in order to vary the mutual distance of the mutually opposite pressers (11a, 11b, 12a, 12b) depending on the dimensions of the flange (40) to be nailed.

8. The machine according to one or more of the preceding claims, characterized in that said variable connection regions are formed by curved slots (16, 17), which are formed coaxially in said center bearing (15).

9. The machine according to one or more of the preceding claims, characterized in that said center bearing (15) is supported so that it can rotate about its own axis (10) by said main supporting structure (2) and in that said rotation means (9) comprise means for the actuation of said center bearing (15) with an intermittent rotary motion about its own axis (10) with respect to said main supporting structure (2).

10. The machine according to one or more of the preceding claims, characterized in that said means for the actuation of said center bearing comprise a gearmotor (26), which is mounted on a framework (20) which supports said center bearing (15) and is connected to said center bearing (15) by means of its output shaft.

11. The machine according to one or more of the preceding claims, characterized in that said framework (20) is supported so that it can slide by said main supporting structure (2) along a substantially vertical direction, translational motion means (33) being provided which act on said framework (20) for its movement along said substantially vertical direction with respect to said main supporting structure (2), which lifts or lowers said center bearing (15) with respect to said worktable (3).

12. The machine according to one or more of the preceding claims, characterized in that said mutually opposite pressers (11a, 11b, 12a, 12b) can move toward or away from each other due to the action of fluid-operated actuators (20a, 20b, 21 a, 21 b) which are mounted on said arms.

Drawing