"HEAD FOR POLISHING CERAMIC ITEMS OR NATURAL STONES"

TECHNICAL FIELD OF THE INVENTION

The present invention refers to a head for polishing, for example by means of smoothing, lapping or the like, ceramic manufactured articles or natural stones.

STATE OF THE ART

With particular reference to the field of the ceramic industry for producing manufactured articles such as tiles, plates or bricks, or of the natural stones, it is known to carry out working, such as complete smoothing or lapping, in order to improve their surface finish.

Such working is generally executed by means of machineries which provide for the use of specific work heads comprising a main body which can be rotated around a relative axis and supporting a plurality of tools suitable for working the manufactured articles.

In particular, the strong friction generated by the action of each tool on the manufactured article leads to an overheating of the work tool itself, so as to necessitate the cooling thereof.

Currently, water cooling systems are in use, which provide for the introduction of the cooling liquid by means of a feed duct that traverses the main body until it reaches the tools.

In detail, the body has a central opening for the outflow of the water in proximity to the work tools.

It is easy to understand that the use of water for cooling the work tools causes a considerable resource and energy consumption.

Another drawback is tied to the need to remove the cooling water.

OBJECTS OF THE INVENTION

The main object of the present invention is to devise a head for polishing ceramic manufactured articles or natural stones, which allows a cooling of the work tools that is efficient, easy to achieve and with limited cost.

Included in such task, one object of the present finding is to reduce the energy expenditure required for cooling the tools.

Another object of the present finding is to devise a head for polishing ceramic manufactured articles or natural stones which allows overcoming the abovementioned drawbacks of the prior art in the scope of a simple, rational solution, with easy and effective use and limited cost.

The abovementioned objects are achieved by the present head for polishing ceramic manufactured articles or natural stones having the characteristics of claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the present invention will be more evident from the description of a preferred but not exclusive embodiment of a head for polishing ceramic manufactured articles or natural stones, illustrated as a non- limiting example in the enclosed drawing tables in which:

figure 1 is an axonometric view of machinery according to the finding;

figure 2 is an axonometric bottom view of a head according to the finding;

figure 3 is a sectional view of the head of figure 2.

EMBODIMENTS OF THE INVENTION

With particular reference to such figures, reference number 1 overall indicates machinery for polishing ceramic manufactured articles, natural stones or the like. The machinery 1 comprises a support frame 2 which is associated with a surface of abutment of the ceramic manufactured articles or natural stones, not represented in the figures, and movable along an advancement direction identified with the arrow 3. The abutment surface is for example the upper surface of a conveyor belt.

In addition, the machinery 1 comprises at least one head 4 for polishing, for example by means of smoothing or lapping, the ceramic manufactured articles or the natural stones arranged on top of the abutment surface. With reference to the particular embodiment solution represented in the figures, the machinery 1 comprises a plurality of heads 4 associated with the support frame 2 and arranged one after the other along the advancement direction 3.

Each head 4 comprises a main body 5 and at least one tool 6 for working the ceramic manufactured articles or the natural stones associated with the main body 5.

Advantageously, each head 4 comprises a plurality of tools 6 associated on the lower part with the body 5. More particularly, each head 4 comprises two, four, six or more tools mounted on the lower part and angularly offset around the body 5.

Usefully, each tool 6 is associated with the body 5 via interposition of a support element 7.

In detail, each support element 7 can be movable in rotation with respect to the body 5 around a relative rotation axis 7a, in a manner such to allow the movement of each tool 6 along a predefined work angle.

The machinery 1 comprises at least one motor element 8 for rotating of each head 4 around a relative axis 9, during use, if desired substantially vertical.

More particularly, the rotation axis 7a of each support tool 6 with respect to the body 5 is substantially transverse or orthogonal to the rotation axis 9 of the head 4. If desired, means are also provided for the angular or oscillating movement of the tools 6 with respect to the body 5, e.g. electric motors or motors of another type, such that the tools 6 can be angularly moved or oscillate around the respective axis 7a during the working or use of the head 4.

In the embodiment shown in figure 1, the machinery 1 comprises a plurality of motor elements 8; in the current case, each motor element 8 is associated with a relative head 4 for rotating the corresponding body 5 around the rotation axis 9. In addition, the machinery 1 comprises means 10, 11, 12 for transmitting the motion from each motor element 8 to the relative head 4.

The motion transmission means 10, 11, 12 comprise at least one first pulley, not visible in the figures, associated with the motor element 8 and at least one second pulley 10 associated with a shaft 11 , which rotatably supports each head 4, and a belt element 12 which connects together the first pulley and the second pulley 10. In this manner, by actuating the motor element 8, the rotary motion generated thereby is transmitted from the first pulley to the second pulley 10 through the belt element 12 and, then, from the second pulley 10 to the head 4 through the shaft 11.

Advantageously, each body 5 comprises an element 13 for attaching to the support frame 2. With reference to the particular embodiment solution represented in the figures, the attachment element 13 is of the type of a flange provided with holes 14 for bolting to a corresponding flanged plate, non represented in the figures, associated with the support frame 2.

If desired, each head 4 can be subjected to a lateral transverse movement, i.e. a movement transverse or orthogonal to the advancement direction of the pieces to be worked; such movement can for example be obtained by means of suitable means for moving a beam or the like of the head support machinery.

According to the finding, the head 4 comprises means 15, 16, 17 for cooling the tools 6, of air type.

In addition, the cooling means 15, 16, 17 comprise at least one channel 17 for delivering air to the tools 6.

With reference to the particular embodiment solution represented in the figures, the cooling means 15, 16, 17 comprise a plurality of delivery channels 17.

Each head 4 comprises at least one delivery channel 17 for each work tool 6.

More particularly, each delivery channel 17 is arranged at each tool 6.

Advantageously, the cooling means 15, 16, 17 comprise at least one air collection chamber 15 and at least one duct 16 for feeding air into the collection chamber itself.

Each delivery channel 17 is communicating with the collection chamber 15.

As is visible in the figures, the collection chamber 15 is arranged at the lower portion of the body 5.

Advantageously, the collection chamber 15 is laterally delimited by a wall 18 having substantially circular shape.

Usefully, the delivery channels branch out from the wall 18.

Preferably, the delivery channels 17 are radially oriented with respect to the rotation axis 9.

In addition, each head 4 comprises at least one closure element 19 sealingly associated with the lower portion of the body 5 and facing the air outlet mouth 20 defined by the feed duct 16.

In detail, the collection chamber 15 is interposed between the closure element 19 and the body 5.

As is visible in the figures, the feed duct 16 traverses the body 5 and comprises a first end 21, connectable with air feeding means, not represented in the figures, adapted to send pressurized air into the feed duct 16, and a second end 22, coinciding with the outlet mouth 20, arranged in proximity to the bottom of the collection chamber 15.

More particularly, the bottom of the collection chamber 15, defined by the closure element 19, is spaced from the outlet mouth 20 so as to allow the flow of the air into the collection chamber itself and towards the delivery channels 17.

Usefully, the rotation axis 9 of the head 4 corresponds to the longitudinal axis of the feed duct 16, which can be rectilinear.

In substance, the cooling means can comprise a feed duct 16 which is at least partly extended along and enclosing a central symmetry axis 9 of the head 4; such feed duct 16 opens on the lower part or on the respective bottom to the delivery channel(s) 17, which open towards the tool(s) 6. If desired, the delivery channel/channels 17 opens/open into a zone that is central, external and below, if desired annular AZ, with respect to the head 4, so as to feed cooling air against the external surface of the tools.

According to the non-limiting embodiment illustrated in the figure, the feed duct 16 is extended along and actually encloses the central symmetry axis, if desired rotation axis 9; such axis 9 if desired also constitutes a central symmetry axis of the feed duct 16 itself. Therefore, the air is centrally conveyed into the feed duct 16 and from this it opens on the lower part or on the bottom into the delivery channels 17; if a chamber 15 is provided, feed duct 16 opens onto the bottom of the underlying chamber 15, in a substantially lower central position of the head 4 and from here, through the delivery channels 17, the air is conveyed on the side of the chamber 15 towards the tools 6, if desired exiting from the head into a zone that is central, external and below AZ the same before externally hitting the tools 6.

The tools 6 are actually mounted around the feed duct 16, in a manner such that cooling air is centrally conveyed to the head 4, and from a central lower position of the latter the air is conveyed substantially radially towards the tools 6. Among other things this allows a delivery of the cooling air that is simultaneously simple and effective.

The feed means can for example be of the type of a compressor group, a turbo- compressor group, a turbine or the like.

In the particular embodiment solution represented in the figures, the delivery channels 17 are arranged tilted with respect to the rotation axis itself and have an air outlet section 23 arranged below the inlet section 24 and directed towards a respective tool 6.

In an alternative embodiment, the delivery channels 17 can be arranged substantially orthogonal to the rotation axis 9 and open towards the relative tool, in a manner so as to hit it substantially parallel to the contact surface with the manufactured article.

In other words, the inlet section 24 and the outlet section 23 are arranged substantially at the same height.

In addition, the machinery 1 comprises means 26 for suctioning the processing residues.

The suction means 26 are arranged on the side of the abutment surface with respect to the advancement direction 3 of the ceramic manufactured articles. For such purpose, the suction means comprise one or more suction cases 26 or the like placed on the sides of the abutment surface. In addition, the cases 26 have a suction opening placed at the height of the interface surface between tools 6 and abutment surface or directed towards such abutment surface.

Such suction means are adapted to remove the processing residues produced by the tools 6 during the working of the ceramic manufactured articles or the natural stones; this ensures the cleaning of the abutment surface during the polishing process.

In addition, a head 4 could also comprise a bell-shaped element 25 or the like, entirely or partly enclosing the main body 5 and delimiting, with the external surface of the main body 5, a zone for conveying cooling fluid, in particular air, towards an abutment surface (for such purpose see the arrows Fl of figure 3). More particularly, the fluid conveyance zone of the bell-shaped element 25 is fed at an upper end thereof with air, for example cooled by means of suitable cooling plant, and is intended to deliver air to the abutment surface, i.e. to an end below the bell-shaped element 25. As will be understood, the air delivered through the conveyance zone of the bell-shaped element 25 would act in combination with the air conveyed by means of the internal cooling means 15 for cooling the tools 6. The bell-shaped element 25, if provided, can be integral with a respective head 4, so as to be moved together with the head 4 in its traverse movement, so that the air conveyed through the bell-shaped element 25 would always be delivered into the zone treated by the head 4.

Alternatively, in place of a bell-shaped element 25, an annular element or the like can be provided, entirely or partly enclosing a head. The operation of the present finding is as follows.

During the passage of the manufactured articles, the heads 4 are rotated around the respective axes 9 by means of the transmission means 10, 11 , 12, so as to obtain the polishing of the manufactured articles due to the action of the tools 6. Simultaneously, the air feeding means send compressed air to the collection chamber 15 by means of the feed duct 16.

The air in the collection chamber 15 is in turn distributed in the delivery channels 17, thus reaching the relative tool 6. In other words, the air is directed towards each tool 6, cooling the latter during the working of the ceramic manufactured articles.

It has in practice been seen that the described invention attains the proposed objects.

In particular, it is underlined that the particular expedient of providing for the air cooling of the work tools allows obtaining an efficient cooling process that is easy to achieve with limited cost, considerably reducing the energy expenditure required for the cooling of the tools themselves.