DESCRIPTION

[0001] The present invention concerns a blade-holder head for cutting textile or cloth materials on automatic spreading tables.

[0002] To perform this operation, among the other cutting means, a head is already known that uses a rectilinear blade having alternate movements. This head, besides being susceptible to translations, in parallel and orthogonal planes with respect to the spreading table, is also susceptible to rotations around a vertical axis to be able to change the forward movement of the blade and make the cut according to the desired trend.

[0003] The blade does in any case need to be correctly supported, guided and lubricated to ensure and maintain its cutting efficiency. Furthermore, because the head has a revolving part, or rotor, to permit the above-mentioned directionality of the blade with a degree of freedom of 360°, it is not easy to convey the lubricating fluid to the cutting end of the blade.

[0004] The object of the present invention is to propose a blade-holder head able to support, guide and lubricate or cool the cutting blade in a perfect way, while at the same time improving the lightness and the overall dimensions of the head itself. [0005] Said object is achieved using a blade-holder head according to claim 1. The dependent claims describe preferred embodiments of the invention.

[0006] The characteristics and the advantages of the blade- holder head according to the invention will in any case appear evident from the description provided below of its preferred embodiments, provided by way of example only and in a non-limitative way, with reference to the attached drawings, wherein:

[0007] - The figure 1 is an axial section of the blade- holder head according to the invention; and

[0008] - The figure 2 is a perspective view of the head from below.

[0009] In said drawings, reference numeral 1 indicates a blade-holder head according to the invention as a whole. The blade-holder head 1 is suitable for supporting a rectilinear blade 2 having alternate movements along a blade axis X for cutting textile or cloth materials stretched on a spreading table.

[0010] In the remainder of the description, reference will be made, for easier exposition, to the blade-holder head 1 in its position of use on a horizontal spreading table, therefore with vertical blade. In this condition, the blade axis X can therefore be deemed vertical.

[0011] In a general embodiment, the blade-holder head 1 comprises first blade guide means 10 suitable for supporting the cutting blade 2 through a plurality of contact points distanced along the blade axis X. For example, the first blade guide means 10 comprise a vertical plate 12 from which extend three blade supports 13 distanced in height, each bearing a pair of rollers with horizontal rotation axis or other means of blade support and guide.

[0012] The first blade guide means 10 are fixed to a guide support body 14, e.g., by means of the vertical plate 12.

[0013] A presser disc 16 is connected at the bottom to said blade support body 10 with the possibility of alternate axial movement by means of a respective actuator (not shown) . Said presser disc 16 supports second blade guide means 18 aligned with said first blade guide means and suitable for supporting and guiding the lower end of the blade 2.

[0014] For the rotation of the blade-holder head 1 around a vertical rotation axis, e.g., coinciding with the blade axis X, a command unit 20 is fitted on an upper crosspiece 22 of the guide support body 14. Said command unit 20 comprises a rotor body 24 suitable for rotating around said rotation axis parallel with said blade axis, and a stationary outer sleeve 26, placed coaxially around said rotor body 24. To allow the rotation of the rotor body 24 with respect to the stationary outer sleeve 26, between the former and the latter are placed friction reduction means, e.g., at least a ball bearing 30.

[0015] In one embodiment, the rotor body 24 comprises a hollow guide unit 32 bearing third blade guide means 34, i.e., upper blade guide means, suitable for supporting and guiding an upper portion of the cutting blade 2.

[0016] The rotor body 24 also comprises, for its rotation, an outer flange 36 bearing a pulley 3,8, the stationary outer sleeve 26 being placed between said pulley 38 and said hollow guide unit 32. More in detail, in one embodiment, the outer flange 36 has a concave shape, i.e., cup shape, defining, with the hollow guide unit 32, an annular seat on which is housed the stationary outer sleeve 26.

[0017] In one embodiment, the outer flange 36 has a threaded side wall 36' for its screwing up into a respective threaded seat 22' made in the upper crosspiece 22 of the guide support body 14.

[0018] In one embodiment, in the stationary outer sleeve 26 are made two annular seats 40 wherein are housed respective seals 42 cooperating with the rotor body 32. Between said annular seats 40 is made a lubrication chamber 44 forming part of the lubrication circuit described below. [0019] In one embodiment, the guide support body 14 has an overturned "L" shape. In other words, said body comprises a side 14' with vertical extension, to which the first blade guide means 10 are fixed and having a height substantially equal to that of said first blade guide means, and the upper crosspiece 22 which extends from the upper end of said side 14' .

[0020] According to one aspect of the invention, the blade- holder head 1 has a lubrication circuit suitable for lubricating the cutting end of the blade 2. Said circuit comprises an entrance hole 50 made in the stationary outer sleeve 26 and suitable for coupling with the lubricant inlet fitting 52. Said entrance hole 50 is in fluidic communication with the annular lubrication chamber 44 made in the outer sleeve.

[0021] A first lubrication duct 54 is made in the rotor body 32 and in fluidic communication with said annular chamber 44. A second lubrication duct 56 in fluidic communication with said first duct 54 extends through the guide support body 14. A third lubrication duct 58 is made in the presser disc 16 in fluidic communication with said second duct and coming out next to the cutting end of the blade 2.

[0022] In a preferred embodiment, the second lubrication duct 56 comprises a coiled tube 56' which extends from the upper crosspiece 22 to the presser disc 16. For example, said coiled tube 56' is connected to a coiled tube fitting 60 accommodated in the upper crosspiece 22 and communicating with the first lubrication duct 54.

[0023] In a preferred embodiment, the other end of the coiled tube 56' is connected to a disc inlet fitting 62, installed on the presser disc 16. Preferably, the third lubrication duct 58 comprises two branches 64 which extend from the disc inlet fitting 62 and which come out on opposite sides of the blade.

[0024] The described blade-holder head therefore permits lubricating the cutting end of the cutting blade with a particularly lightweight and compact head structure, where the stationary part, , wherein the lubrication chamber is made, is reduced to the sole outer sleeve. Such sleeve, as can also be appreciated by the drawings, has a small axial dimension, which does not affect the total height of the head.

[0025] T h e use of the coiled lubrication tube- advantageously permits the axial movements of the presser disc to which it is connected.

[0026] The reduction in overall height dimensions of the command unit permits optimizing the blade support and guide, increasing the height extension of the first guide means and/or the number of contact points with the blade. [0027] The lightened and open structure of the blade-holder head, as well as the embodiment of the lubrication circuit, make the assembly and maintenance of the device particularly easy.

[0028] To the embodiments of the blade-holder head according to the invention, a man skilled in the field, to satisfy contingent requirements, can make changes, adaptations and replacements of parts with others of equivalent function, without departing from the scope of protection as defined by the appended claims. Each of the features described as belonging to a possible embodiment can be made separately from the other described embodiments .