EP1186379A2

EP1186379A2 - Device for surface grinding and sanding

Info

Publication number: EP1186379A2
Application number: EP01112054A
Authority: EP
Inventors: Bruno Oliosi; Claudio Mazzolini
Original assignee: Tholes Srl
Priority date: 2000-09-07
Filing date: 2001-05-25
Publication date: 2002-03-13
Anticipated expiration: 2021-05-25
Also published as: EP1186379A3; DE60117316D1; EP1186379B1; ITBO20000520A0; ES2262575T3; ITBO20000520A1; DE60117316T2

Abstract

The subject matter of the invention is a device for surface grinding and sanding through orbital rotating machines.

This device consists in a pad (1), an abrasive disc (2) to be fixed to the pad, tools (201) to fix the pad to the orbital rotating machine, tools (501) to fix abrasive disc to the pad.

The device is characterised by the fact that the pad includes at least some empty spaces (601).

Description

The subject matter of the invention is a device for surface grinding and sanding through orbital rotating machines which consists in a pad, an abrasive disc to be fixed to the pad, tools to fix the pad to the orbital rotating machine, tools to fix abrasive disc to the pad.
Today, traditional devices of the same kind are known. These traditional devices include a pad consisting in a rigid plastic or metal disc on which, by chemical physical adhesion, a disc made up of soft and elastic damping material, such as rubber or neoprene, is fixed. The surface of these traditional devices is equipped with eight diametral through holes, whose centres are placed on a circumference which is in a coaxial position as regards to the pad itself. These pads are usually equipped with a central hole with function of both suction and, in case, pad fixing to a driving spindle with a through bolt or similar. Through holes also have the function of eliminating sanding rests during grinding and/or sanding activities.
Obviously, traditional abrasive discs too are equipped with holes, and in case with a central hole, corresponding to the pad holes, for the elimination of material removed during sanding activities Therefore, the total amount of holes is nine.
The use in combination of these traditional devices causes the problem of hindering the maintenance of a correspondence between diametral holes on the pad and those on the abrasive discs. In fact, while sanding, it is possible that abrasive disc moves on pad surface, in particular when a stronger pressure on the pad axle is exerted.
Moreover, these traditional devices consisting in a rigid disc on which is fixed a disc made up of soft damping material, by chemical physical adhesion, especially by gluing, are characterized by a low thermic conductivity, which leads to an insufficient cooling level of the pad and of the abrasive disc. Heat generated during sanding activities can reach temperatures ranging from 80 to 90 ° C, leading to a rapid deterioration of gluing materials joining damping disc and rigid disc, as a consequence it is possible that the two discs come unstuck. High temperatures reached while sanding also cause a rapid alteration of abrasive disc components, therefore frequent disc replacement become necessary and sanding machine inactivity periods increase.
A further inconvenient caused by traditional devices is the loading effect, due to the fact that sanding rests can just be eliminated through a limited number of holes. This effect creates a sanding rests layer on the abrasive disc surface which leads to a worsening in sanding machine performance and, most of all, to a further decrease of heat disposal.
Sanding rests are eliminated through suction, thanks to a suction casing enclosing the spindle and overlapping the pad on the opposite side of abrasive disc application surface.
The circumference of the above mentioned casing is large enough to overlap at least the area where through holes are located and, in pad operating position , it places itself with the opening edge at a minimum distance from the opposite side of the pad. The space inside the casing is linked to whatever suction devices, such as suction pumps or devices creating depression through Venturi effect or similar.
The invention is based on the issue of creating a pad corresponding to the description here above and a support of an abrasive disc solving above mentioned inconveniences due to traditional devices through simple, cheap and fully effective devices, so that the pad itself can be replaced by well known traditional pads without any change to orbital rotating machines.
The invention solves the above mentioned problems thanks to a pad corresponding to the description here above and characterized by the fact that it includes at least some empty spaces.
This pad can be made in two separate parts on a plane which is perpendicular to the pad rotation axis and at least one of the two parts must include at least some empty spaces.
These two parts forming the pad are subsequently joined together by chemical physical adhesion, in detail by welding or gluing or by mechanical joining or mutual clamping devices.
The pad being part of the invention is characterized by a certain number of through holes, whose centres are located on a circumference which is coaxial to the pad itself.
At least one of the two sides of the pad, that is the side supporting the abrasive disc and/or the opposite side, can be equipped with several hole rows located on different circumferences.
The holes belonging to different coaxial rows can be radially lined up between them or can be radially staggered between them and they can have different diametres.
In particular, pad side opposite to the side supporting abrasive disc or where the abrasive disc is applied, is equipped with just one through hole row located on a circumference corresponding to one of the through hole row circumferences on the pad side where the disc is fixed. The two hole rows on the above mentioned two sides can be lined up, or partially or completely angularly staggered.
On a practical form, the pad can also be equipped with a central hole for suction or in case for fixing devices, such as through bolts or similar, to the spindle of a orbital rotating machine.
According to another practical form, the central part of the pad, in co-axial position to the pad itself, is equipped with a metal element, fixed or inserted or incorporated to the pad itself, in form of disc or non-round shaped extending on the opposite side of the pad in form of a stem or fixing axle to the spindle of a orbital rotating machine.
Preferably, at least some of the holes are located in such a way to form couples of holes diametrically opposite one to the other.
In case these diametrical holes are located as in a traditional pad, the use of traditional abrasive discs would be easier, since these holes correspond at least partially with the holes of the traditional abrasive disc.
The number of holes is variable and it can be identical or different for the two opposite sides which are transversal to the pad rotation axis.
Preferably, the pad side supporting the abrasive disc is equipped with a variable number of holes, in particular ranging from 10 to 1.450.
The side parallel to the disc and opposite to the side where the abrasive disc is fixed is instead preferably equipped with a lower number of holes.
The creation of the pad at least partially empty, gives the advantage of enhancing cooling effect, since during pad rotation air can circulate inside the pad both naturally and thanks to the use of forced ventilation devices or suction devices such as those here above described and widely used on well known orbital rotation machines.
Abrasive disc equipped with several holes, whose diametre is considerably smaller than the diametre of traditional abrasive disc holes and whose disposition on the surface is appropriately conceived, gives the advantage of enhancing both sanding rests elimination and cooling effect, since air is distributed on all the holes.
Moreover, the fact that the holes are distributed on the whole abrasive disc surface solves the problem of possible moving of the disc on the pad. This problem occurring with traditional discs leads to a considerable decrease of usable area for sanding rest circulation and cooling air.
A preferable practical form includes a combination of pad and abrasive disc as described here above, where both pad side where the abrasive disc is fixed and the abrasive disc itself are equipped with the same number of holes distributed on abrasive disc surface and on surface of abrasive disc adhesion to the pad, showing identical drawings. The holes can have different dimensions radially located between them or according to sub-rows of the total amount of holes, being the diametre of the holes or hole sub-rows on the pad side where abrasive disc is fixed identical to the diametre of abrasive disc holes and to be fixed in coinciding position with the former.
An improvement enabling the correct coinciding position of the abrasive disc holes on the side of the pad equipped with the same kind of holes, is suggested by the invention by adding to the hole distribution drawing, as for hole location and dimension, hole combinations based both on lining up or location and on different hole dimension combination being immediately identifiable both on abrasive disc and on pad side and easily positioned in the correct coinciding position.
Profitably, one of these combinations is characterized by a radial location of a certain number of holes, both on the disc and on the pad, being different dimension holes radially lined up at least for a part of the holes.
For instance: four holes, radially lined up, two of these, radially lined up in intermediate position, side by side, have a smaller diametre, while the radially more internal hole and the radially more external hole are larger, but their dimensions are different and respectively larger and intermediate referring to the dimension of smaller intermediate holes.
It is also possible to take into consideration two or more similar or identical hole combinations as those above mentioned, in different points or different angular positions, in order to determine the correct mutual positioning.
Thanks to this expedient, air and dust flow is easily directed into pad cavity and flow compensations and distributions transversely to the pad axis occur inside the pad itself. This gives the advantage of reducing the number of layers of the disc or of the pad side where the disc is fixed, avoiding a layer made of air resistant material generating transversal micro-passages for air and dust flow distribution.
Moreover, this project allows also the use of pads on which self-adhesive discs can be applied. The surface of the side of this kind of pads must be featuring characteristics enabling the adhesive of the abrasive disc to grip, but at the same time the disc should also be easily removed. Due to their structure, this kind of surfaces usually do not allow the creation of micro-passages transversely to the pad axis and therefore in this case transversal flow distribution or compensation could not be guaranteed.
Invention improvements are described into sub-claims.
Invention characteristics and the advantages it brings will be more widely explained in the description here below, where a practical non-restricted example is illustrated in detail thanks to enclosed drawings.
Picture N.1 shows a side view of the pad.
Picture N.2 shows an external front view of the pad side where abrasive disc is applied.
Picture N.3 shows a view from above on the external side of the pad side opposite to the one where the abrasive disc is fixed or applied.
Picture N.4 shows a side section of the "cup" shaped part of the pad.
Picture N.5 shows a front view of the internal side of the "cup" shaped part of the pad.
Picture N.6 shows a front view of the abrasive disc equipped with several holes.
Picture N.7 shows a view from above of a hole distribution drawing which is identical both for the abrasive disc and for the pad side where this abrasive disc is fixed.
Picture N.8 shows a view which is similar to picture N.7 of a further practical form.
Referring to the pictures, the pad described by the invention consists in two parts 1, 2 separated on a plane which is perpendicular to the pad rotation axis and at least one of the two parts must include at least some empty spaces.
The empty part of the pad, "cup" shaped 1, consists in a disc made up, in particular but not restrictively, of plastic material, equipped with several through holes 601, whose centres are located on a circumference which is co-axial to the pad rotation axis.
In order to allow the use of traditional abrasive discs too, the number of the above mentioned diametrical holes 601 can be nine or six, according to the pad type.
The peripheral side of the "cup" shaped part of the pad is equipped with a 301 small edge fit for fixing of closing disc 2 of the "cup" shaped part 1 of the pad, which has a ∝ acute angle inclination as regards the pad plane.
The above mentioned edge 301 is equipped with a perimetral tooth 401 enabling the joint insertion of closing disc 2 into the "cup" shaped part 1 of the pad.
An insert 101 having a smaller diametre than the pad is fixed in the middle of the "cup" shaped part 1 of the pad, on the external surface. The insert 101, in particular but not restrictively made up of metal, can be fixed in any way and in particular it can be incorporated in the material constituting the "cup" shaped part 1 of the pad. The part of the metal insert 101, preferably round shaped, incorporated into the pad, extends on the external side of the "cup" shaped part 1 of the pad itself thanks to a connection stem 201 fit to be tightened or screwed or otherwise connected to a spindle or other connection devices with a rotating driving shaft of the pad itself.
As an alternative to the option above described, the pad, that is the "cup" shaped part, can be equipped with a central through hole, in particular co-axial, enabling the fixing of the pad to the rotating driving shaft of the orbital rotation machine or to a spindle with a through bolt or similar. Both options are well known and currently used for pads.
The internal surface of the "cup" shaped part 1 of the pad is equipped with several projections or ribbings 501, located near diametrical holes 601 and/or by a more internal circumference and in the area of the central metal insert 101, having the function of enabling the leaning and/or further fixing of the closing disc 2 of the "cup" shaped part 1 of the pad.
Closing disc 2 of the "cup" shaped part 1 of the pad is equipped with several diametrical through holes 102, whose centres are located on three different circumferences which are co-axial between them and to the pad axis. The number of holes forming these hole rows is not the same, and their angular positions do not correspond one to the other and moreover they are at least partially characterized by different diametres. In detail, the two rows in more external position are formed by larger diametre holes, while the more internal row is formed by smaller diametre holes, on one row the centres of the above mentioned holes are located on the same circumference as the hole row 601 of the "cup" shaped part 1. In that case the hole row 102 of the closing disc 2 and 601 of the "cup" shaped part 1 can be lined up, or partially or completely angularly staggered.
Moreover, closing disc 2 is equipped with a central hole 202, which is characterized by a considerably larger diametre, in detail about 1,5 times larger and preferably the double than the diametre of holes belonging to row 102. Closing disc 2 102 holes on the same circumference as holes 601 of "cup" shaped part 1 of the pad have a smaller diametre than holes on the "cup" shaped part 1.
External surface of closing disc 2 on the "cup" shaped part 1 of the pad is at least partially covered with a damping material layer 302, consisting in particular in a soft and elastic material such as rubber, neoprene or similar. The above mentioned layer is glued with a removable fixing material layer 402, named "velcro" and also definable as pull fixing and enabling the adhesion of the abrasive disc equipped with the complementary layer of the removable fixing mean, which usually consists in a cloth as velour or similar.
As an alternative to the above described pull fixing device, it is possible to equip the abrasive disc back with an adhesive material layer.
Obviously, damping material layer 302, and in case the pull fixing material layer of the disc (velcro or similar) 402 are equipped with through holes corresponding to the holes of closing disc 2. The two parts forming the pad, that is "cup" shaped part 1 and closing disc 2, are subsequently joined by the peripheral external tooth 401 of the "cup" shaped part 1 and by projections or ribbings 501 inside the "cup" shaped part 1 by physical chemical adhesion, in detail melding or gluing.
In a second practical form of the pad, projections and ribbings 501 inside the "cup" shaped part 1 can also be equipped with an internal threaded hole, so that the pad closing cap can be fixed in a removable way with screws. In that case, closing cap 2 too on the "cup" shaped part 1 of the pad is equipped with through holes level with projections or ribbing holes on "cup" shaped part 1.
Closing cap 2 holes, in case of screw fixing, are countersunk on the external surface so that flaring head screws can be inserted inside, in order to avoid protrusions on the external surface of the pad.
Even on this second practical form, closing cap on the "cup" shaped part 1 of the pad is at least partially covered with the damping layer 302 and in case with velcro layer or similar 402.
Having the possibility to fix closing cap in a removable way, it is possible to replace closing cap every time with the most suitable one, according to the abrasive disc to be used. Therefore, the pad can be adapted to several kind of discs, belonging both to the traditional type and to the new concept.
The above described pad project being part of the invention, considerably improves air circulation inside the pad, enhancing in this way thermic exchange.
In order to improve sanding rests suction from abrasive disc 3, homogenizing suction effect on the surface of the disc itself and avoiding in this way inconveniences characterizing six or nine holes traditional abrasive discs, as above described, abrasive disc is equipped with several through holes 103.
The above mentioned holes 103 are appropriately distributed on abrasive disc surface, in detail, in an homogeneous way and hole diametre can range from a minimum of 0,5 mm and a maximum of 8 mm, and their density can range from 0,5 to 8 holes per square centimetre.
The surface of the abrasive disc being in contact with the pad is at least partially covered with a layer of cloth as velour or similar so that it can grip with the pad itself which is covered with a male layer consisting in pull closing material as velcro, as previously described referring to the pad itself.
Obviously, velcro or similar material layer too is equipped with perforations level with the abrasive disc layer.
Abrasive disc parts covered with velcro are particularly helpful for dust transfer from abrasive discs parts not coinciding with holes to pad suction holes themselves, since the structure of pull fixing materials, as velcro, creates small hollow spaces enhancing air circulation for dust suction.
An abrasive disc equipped with several holes, uniformly distributed, avoids the problem of disc moving between pad suction holes and disc holes, frequently occurring with traditional abrasive discs, improving in this way dust suction.
A further benefit of this kind of abrasive disc consists in the improvement of elimination of heat generated during polishing or sanding, due to the fact that air suction occurs on the whole surface of the disc.
Moreover, being the holes distributed on the whole surface of the disc, it is possible to use it indiscriminately with the two kinds of pad, six or eight holes, being the problem of hole overlapping or moving non-existent.
Referring to the example in picture N.7, this picture illustrates a view from above of a hole distribution drawing which is identical both on the abrasive disc and at least on the pad side where abrasive disc is fixed.
This combination of pad and abrasive disc keeps in every possible combination or sub-combination all compatible characteristics previously described with examples, above described possible versions included. The side of the pad where the abrasive disc is fixed and the abrasive disc itself have the same number of holes F which are distributed on the surface of the abrasive disc and of the side of the pad where the disc is fixed according to identical drawings or patterns. F, F', F" holes can have different dimensions between them or according to sub-rows of the total number of holes. Holes or hole sub-rows on the side of the pad where abrasive disc is fixed having exactly the same diametres as the holes on the abrasive disc are to be fixed level with abrasive disc holes.
Moreover, in order to fix abrasive disc in the correct position, that is the holes level with the holes on the pad side, hole distribution drawing shows hole sub-combinations or sub-rows which are immediately identifiable both on abrasive disc and pad side. The above mentioned sub-rows or combinations can be identified from the rest of the holes thanks to a particular distribution of the above mentioned holes between them both based on their disposition and dimension. Hole sub-combinations or rows are also chosen in such a way to facilitate abrasive disc fixing in its correct position, that is the abrasive disc holes level with pad holes.
The example described illustrates a radial disposition of a certain number of holes, in detail 4 marked with 20 and present both on disc and pad, having the radially lined up holes different dimensions between them at least for a part of the holes themselves.
The example shows four holes, radially lined up, two of these, marked F holes, radially intermediate and side by side have a smaller diametre, while the radially more internal hole F' and the radially more external hole F" have larger dimensions, different one from the other and respectively larger and intermediate referring to the dimension of smaller intermediate holes.
Two or more similar or identical hole sub-combinations 20 are possible, for correct mutual positioning definition, in different points or different angular positions.
Thanks to this device, air and dust flow is easily directed into pad empty spaces and flow compensations or distributions in transverse sense to the pad axle occur inside the pad itself.
A further practical form is illustrated by picture N.8. In this case hole distribution is based on a pattern consisting in relatively small holes having substantially the same dimension and located at the crossing point of two groups of ideal parallel lines I, I' intersecting between them. Therefore, general hole disposition pattern, according to picture N.7 described a hole distribution on circles which were concentric with the pad circle in points of intersection with radius or diametres starting from this centre, while distribution pattern described in picture N.8 shows a hole distribution along quadrilaters, in detail ideal squares where the intersecting point of the diagonals coincides with the centre of the disc or of the pad. It is worth to underline how the example in picture N.8 can include distribution irregularities as the one indicated by hole 21 and which is based on the same principle as sub-combination 20, that is the elimination of two adjacent holes along at least two adjacent ideal parallel lines and the replacement of these holes with one hole 21 located in intermediate position between the position of the two replaced holes and that is of the two lining up parallel lines. It is also possible to define other kinds of distribution unhomogeinities or irregularities according to other patterns.
In order to facilitate abrasive disc F holes lining up with pad holes, hole sub-combination 20 consists in two larger diametre holes F', diametrically opposite lined up on the same diametre with F holes, 21 smaller diametre holes among which one hole 21 is located laterally staggered as regards the two lining up ideal intersecting lines crossing point in intermediate position between two lining up lines perpendicularly located as regards lining up diametre on which F' larger diametre holes are present, being left out the holes on crossing points of the above mentioned lining up lines perpendicularly located as regards lining up diametre marked by two larger diametre F' holes.
Obviously the invention is not limited to the elements above described and illustrated, on the contrary, it can be largely varied, most of all from a constructional point of view. For instance there is no limitation to the application of this invention to abrasive discs with different diametres. Moreover, the project above described as regards circular pads and abrasive discs can be directly applied, without any change to the invention, to non-round shaped pads fit for abrasive sheets support, since both sheets and/or non-round shaped pads can be carried out as above described and afterwards claimed.
It is also possible to apply this invention, without any addition to the invention itself but just thanks to simple changes, to plates for abrasive belt pieces support or fixing on orbital or reciprocating motion machines. In that case abrasive belt pieces too can be perforated as those currently well known or carried out following this invention project. All this, always taking into consideration the invention project above described and afterwards claimed.

Claims

Device for surface grinding and sanding through orbital rotating machines consisting in a pad, an abrasive disc to be fixed to the pad, tools to fix the pad to the orbital rotating machine, tools to fix the abrasive disc to the pad and characterized by the fact that the pad includes at least some empty spaces.
Device according to the previous claim characterized by the fact that pad consists in two separate parts on a plane which is perpendicular to the pad rotation axis and at least one of the two parts must include at least some empty spaces or "cup" shaped parts.
Device according to one or more previous claims characterized by the fact that the "cup" shaped part of the pad consists in a circular element equipped with several diametral through holes (601), the centre of which are located on at least one circumference being co-axial with the pad rotation axle.
Device according to one or more previous claims characterized by the fact that the "cup" shaped part is equipped with a central hole (701).
Device according to one or more previous claims characterized by the fact that the peripheral side of the "cup" shaped part of the pad is equipped with a small supporting edge (301) fit for fixing of closing disc 2 of the "cup" shaped part of the pad.
Device according to one or more previous claims characterized by the fact that the small edge 301 is equipped with perimetral tooth enabling the insertion of the closing disc into the "cup" shaped part of the pad.
Device according to one or more previous claims characterized by the fact that in the middle of the "cup" shaped part of the pad an insert (101) is fixed or incorporated inside the material constituting the "cup" shaped part of the pad and from here it extends through a stem for rotating motion transfer to the pad.
Device according to one or more previous claims characterized by the fact that the internal surface of the "cup" shaped part of the pad is equipped with several projections or ribbings (501) for leaning and/or fixing of the closing disc (2) of the "cup" shaped part itself.
Device according to one or more previous claims characterized by the fact that ribbings are located near through holes on the "cup" shaped part.
Device according to one or more previous claims characterized by the fact that the central area of the "cup" shaped part (1) is equipped with projections and ribbings (501).
Device according to one or more previous claims characterized by the fact that closing disc on the "cup" shaped part of the pad is equipped with several through holes (102), whose centres are located on at least one circumference being co-axial to the pad.
Device according to one or more previous claims characterized by the fact that the closing disc on the "cup" shaped part of the pad is equipped with a central hole (202).
Device according to one or more previous claims characterized by the fact that at least one of the two pad sides parallel to the disc, that is the side supporting the abrasive disc belonging to the "cup" shaped part and/or the opposite side, that is closing disc, can be characterized by several hole rows (102) located on different circumferences.
Device according to one or more previous claims characterized by the fact that holes belonging to different co-axial rows can be at least partially radially lined up between them, or at least partially staggered between them and they can have at least partially different or identical diametres.
Device according to one or more previous claims characterized by the fact that the pad side opposite to the abrasive disc application or support side is equipped with just one through hole row located on a circumference corresponding to one of the through hole row circumferences on the pad side where the disc is fixed.
Device according to one or more previous claims characterized by the fact that the two hole rows on the above mentioned two sides can be lined up, or partially or completely staggered angularly and/or radially between them.
Device according to one or more previous claims characterized by the fact that the pad is also equipped with a central hole for suction or in case for fixing devices, such as through bolts or similar, to the spindle of an orbital rotating machine.
Device according to one or more previous claims characterized by the fact that also closing disc diametral holes (102) are at least partially arranged in the same way as traditional abrasive discs holes.
Device according to one or more previous claims characterized by the fact that the number of holes is variable and it can be identical or different for the two opposite empty pad sides which are transversal to the pad rotation axis.
Device according to one or more previous claims characterized by the fact that the pad side supporting the abrasive disc is equipped with a variable number of holes, in particular ranging from 10 to 1.450.
Device according to one or more previous claims characterized by the fact that the side parallel to the disc and opposite to the side where the abrasive disc is fixed is preferably equipped with a smaller number of holes.
Device according to one or more previous claims characterized by the fact that the centres of the holes belonging to at least one hole row on pad closing disc are located on the same circumference as at least one hole row on the "cup" shaped part (1).
Device according to one or more previous claims characterized by the fact that holes belonging to hole rows on closing side and on "cup" shaped part can be lined up between them, partially angularly and/or radially staggered or completely angularly and/or radially staggered between them.
Device according to one or more previous claims characterized by the fact that holes on the closing discs located on the same circumference as those on the "cup" shaped part of the pad have a smaller diametre than those on the "cup" shaped part.
Device according to one or more previous claims characterized by the fact that closing disc central hole has a larger diametre than the hole row.
Device according to one or more previous claims characterized by the fact that the external surface of closing disc on the "cup" shaped part of the pad is at least partially covered with a damping material layer, consisting in particular in a soft and elastic material such as rubber, neoprene or similar. This damping material layer is equipped with holes which are at least partially lined up with those on the closing disc on which it is applied.
Device according to one or more previous claims characterized by the fact that closing disc and damping layer are glued with a removable fixing material layer, named "velcro" and also definable as "pull fixing material" and enabling the adhesion of the abrasive disc equipped with the complementary layer of the removable fixing mean, which usually consists in a cloth as velour or similar. The pull fixing layer is equipped with holes which are at least partially lined up with those on the closing disc on which it is applied.
Device according to one or more previous claims characterized by the fact that closing disc and damping layer on it are glued with at artificial leather layer, or similar for removable fixing of adhesive abrasive disc also called stickit (adhesive discs).
Device according to one or more previous claims characterized by the fact that the two sides constituting the pad, that is the "cup" shaped part and the closing disc, are joined together level with the external small edge (301) of the "cup" shaped part and with the projections and ribbings (501) inside the "cup" shaped part through chemical physical adhesion.
Device according to one or more previous claims characterized by the fact that chemical physical adhesion is obtained by welding and/or gluing.
Device according to one or more previous claims characterized by the fact that projections and ribbings (501) inside the "cup" shaped part are equipped with an internal threaded hole, so that the pad closing cap can be fixed in a removable way with screws, since the closing disc on the "cup" shaped part of the pad is equipped with through holes level with projections or ribbings holes on the "cup" shaped part.
Device according to one or more previous claims characterized by the fact that closing cap holes are staggered on the external surface of the disc itself.
Device according to one or more previous claims characterized by the fact that as an alternative to the pull fixing device (velour or similar), it is possible to equip the abrasive disc back with an adhesive material layer.
Device according to one or more previous claims characterized by the fact that the abrasive disc is equipped with several through holes (103).
Device according to one or more previous claims characterized by the fact that the above mentioned holes 103 are appropriately distributed on abrasive disc surface and hole diametre can range from a minimum of 0,5 mm and a maximum of 8 mm, and their density can range from 0,5 to 8 holes per square centimetre.
Device according to one or more previous claims characterized by the fact that abrasive disc holes (103) are distributed in detail in a more or less homogeneous way.
Device according to one or more previous claims characterized by the fact that abrasive disc surface leaning on the pad is at least partially covered with a layer of cloth as velour or similar so that it can grip with the pad itself which is covered with a male layer consisting in pull closing material as velcro.
Device according to one or more previous claims characterized by the fact that abrasive disc and at least the pad side where the abrasive disc is fixed are equipped with exactly the same hole distribution drawing (F, F', F").
Device according to one or more previous claims characterized by the fact that pad side where abrasive disc is fixed and abrasive disc itself are equipped with the same number of holes (F) which are distributed on abrasive disc surfaces and on surface of abrasive disc adhesion to the pad, showing identical drawings or patterns.
Device according to claim 38 or 39, characterized by the fact that (F, F', F") holes can have different dimensions between them or according to sub-rows of the total amount of holes.
Device according to one or more previous claims 38 to 40, characterized by the fact that holes or hole sub-rows on the side of the pad where abrasive disc is fixed, having exactly the same diametre as abrasive disc holes, are obviously to be fixed lining them up with abrasive disc holes.
Device according to one or more previous claims 38 to 41, characterized by the fact that both pad and abrasive disc are equipped with mutual reference notches for correct lined up positioning on the base of the respective hole distribution drawing.
Device according to claim 42, characterized by the fact that the above mentioned notches or mutual positioning keys consist in hole sub-combinations or sub-rows, showing identical drawings or positioning patterns which are immediately identifiable both on abrasive disc and pad side.
Device according to claim 43, characterized by the fact that the above mentioned hole sub-combinations or sub-rows can be identified from the rest of the holes thanks to a particular hole distribution pattern (20) both based on disposition and dimension of the holes themselves.
Device according to claim 44, characterized by the fact that the particular hole sub-row or sub-combination (20) drawing or pattern includes a radial disposition of a certain number of holes, in detail ranging from 2 to 8 which is present both on disc and pad.
Device according to claims 44 or 45, characterized by the fact that holes belonging to each sub-row or sub-combination have different dimensions between them at least for a part of the holes themselves.
Device according to one or more previous claims 38 to 46, characterized by the fact that sub-row or sub-combination are equipped with four holes, radially lined up, two of these, radially lined up in intermediate position, side by side, have a smaller diametre, while the radially more internal hole and the radially more external hole are larger, but their dimensions are different and respectively larger and intermediate referring to the dimension of smaller intermediate holes.
Device according to claim 47 characterized by the fact that it includes two or more similar or identical hole sub-combinations or sub-rows (20), which can be in different points or different angular positions of the pad and abrasive disc.
Device according to one or more previous claims 38 to 46, characterized by the fact that it includes two or more similar or identical hole sub-combinations or sub-rows (20), which can be in diametrically opposite positions between them, being holes F, F', F" lined up on a pad or abrasive disc diametre and having radially more external holes a larger diametre and those radially more interrnal a smaller diametre.
Device according to claim 49, characterized by the fact that holes F, F' are located level with crossing points with the above mentioned lining up diametre of a group of parallel lines equidistant one from the other and perpendicularly located as regards the above mentioned diametre, having been left out holes in two adjacent crossing points and replaced with one hole located in laterally staggered position and in intermediate position between two adjacent crossing points of the above mentioned group of parallel lines with lining up diametre, level with the two crossing points the above mentioned left out holes miss.
Device according to one or more previous claims characterized by the fact that the pad is not round shaped it fits as support for so-called abrasive sheets.
Device according to one or more previous claims characterized by the fact that it consists in a plate for abrasive belt pieces support or fixing on orbital or reciprocating motion machines, being this plate carried out similarly to the pad according to one or more previous claims.
Device according to one or more previous claims characterized by the fact that it consists in a plate for abrasive belt pieces support or fixing on orbital or reciprocating motion machines, being this abrasive belt piece carried out a according to one or more previous claims.
Abrasive disc for pads characterized by the fact that it owns the characteristics of one or more previous claims.