EP2865491A1

EP2865491A1 - Sanding device having a detachable abrasive medium

Info

Publication number: EP2865491A1
Application number: EP20130190144
Authority: EP
Inventors: Hubert Gillissen; Leendert Van Zanten
Original assignee: Sanduplex BV
Current assignee: Sanduplex BV
Priority date: 2013-10-24
Filing date: 2013-10-24
Publication date: 2015-04-29

Abstract

It is described a surface treatment device (1) comprising a holder (2) for hand-held or powered tools, an mounting plate (3) having an abrasive medium (4), and mounting means (5) between the holder (2) and the mounting plate (3). Furthermore the device (1) is provided with detachable mounting means (6, 6-1, 6-2) between the mounting plate (3) and the abrasive medium (4). The latter means may be formed by corresponding pins (6-1) and apertures (6-2), and/or attracting magnetic materials. In one embodiement the pins (6-1) are hollow and expanable in width by means of pressure.

Description

The present invention relates to a surface treatment device comprising a holder for hand-held or powered tools, a mounting plate having an abrasive medium, and mounting means between the holder and the mounting plate.
The invention also concerns an abrasive medium suited for application in the above surface treatment device.
Such a surface treatment device for sanding or polishing purposes is known from US-7,040,973 B1 . The known device comprises a holder adaptable to hand-held or powered tools and a one piece mounting plate having an abrasive medium. The abrasive medium is permanently fixed to the abrasive sheet by mounting means in the form of an adhesive bond there between. The device further comprises detachable mounting means in the form of holding pins on the holder and apertures extending in a support member of the one piece mounting plate. The apertures and the corresponding pins on the holder are detachable from one another for exchanging the one piece mounting plate.
In certain applications with air-vacuum features the holder, the mounting plate and the abrasive medium each have axially aligned vacuum apertures ending in the lower outer surface of the abrasive medium, wherein the apertures are die cut. Such features are common in powered sanding tools.
It is an object of the present invention to provide a low-cost surface treatment device which is more easily adaptable to wanted surface treatments, more cost effective and suited for application by a broader range of the general public without scarifying quality of the treatment and handling ability of the surface treatment device.
Thereto the device according to the invention is characterised in that the surface treatment device (1) comprises detachable mounting means provided between the mounting plate and the abrasive medium for manually detachably holding the abrasive medium on the mounting plate.
It is an advantage of the device according to the present invention that by providing detachable mounting means between the engaging mounting plate and the abrasive medium an extra degree of flexibility and exchangeability of abrasive media has been introduced in the device. Now different types of mounting plates can be exchanged, in some embodiments even manually without tools being required. In cases where surface treatments with increasing degrees of fineness is requested, no earlier required exchange of the complete mounting plate is needed, which eases handling. Further advantageously the same mounting plate can stay on the device and can now be used several more times for other abrasive media, which also saves costs.
An embodiment of the device according to the invention has the characterising features that the detachable mounting means comprise pins and apertures for accommodating and tightening the pins, which detachable mounting means are provided on contact surfaces between the mounting plate and the abrasive medium.
Advantageously no tools are necessary for either removing from or applying the abrasive medium now easily manually to the sheet. Furthermore it is advantageously that if the pins and apertures snugly fit into one another there is no play between the device and the abrasive medium, which means that a high quality surface treatment end result can be achieved.
A preferred embodiment of the device according to the invention has the characterising features that the abrasive medium having opposing contact surfaces has at least one abrasive outer contact surface.
This abrasive medium is exchangeable, but if both opposing abrasive outer contact surfaces are abrasive then advantageously the exchanged sheet can be turned around and used further with its other abrasive surface. Further advantageously both surfaces may be identical in surface roughness degree or may be different.
A further preferred embodiment of the device according to the invention has the characterising features that the abrasive medium comprises a support layer having one abrasive outer contact surface, or being sandwiched between the two contact surfaces, whereby the apertures end in the support layer, or are apertures running through both contact surfaces and the support layer.
It is an advantage of the device according this embodiment that the part of the apertures, or those apertures extending through the lower outer abrasive surface of the mounting plate are capable of catching dust generated during the polishing, grinding or sanding of an object whose surface is treated. After some time the dust may simply be shaken out of the apertures, without substantial powered vacuum feature investments being required. So the one end of the apertures is used to hold and clamp the pins while the other end is used to collect dust from the treatment of the surface of an object. Due to the collecting of dust in the apertures the end result will be better, as less dust interferes in the surface treatment process between the lower medium surface and the surface of the object to be treated.
At present the device according to the invention will be elucidated further together with its additional advantages, while reference is being made to the appended drawing, wherein similar components are being referred to by means of the same reference numerals. In the drawing:

Figs. 1A and 1B show a side view and a perspective view respectively of main parts of a first embodiment of the device according to the invention;
Figs. 2A and 2B show a side view and a perspective view respectively of main parts of a second embodiment of the device according to the invention;
Figs. 3A and 3B show a third embodiment of the device according to the invention having a support layer, and a detail thereof respectively;
Figs. 4A and 4B show a fourth embodiment of the device according to the invention having a manual detachable mounting means formed by clamping the outer rim of the medium between a tab member of the sheet;
Figs. 5A and 5B, and 6A and 6B respectively show fifth and sixth embodiments of the device according to the invention having a detachable mounting means formed by expandable pins clamping in the apertures; and
Figs. 7A, 7B and 7C show a seventh embodiment of the device according to the invention having a two part mounting plate.

These figures each show embodiments of a surface treatment device 1, some details whereof are omitted herein but can be found in US-7.040.973 B1 , whose disclosure is included herein by reference thereto. The device 1 comprises a holder 2 only schematically indicated as being a haft for a hand-held device. Other holders forming a casing not shown here may be used to mount the device 1 in a powered tool for sanding or polishing. The device 1 further comprises a mounting plate 3 having an abrasive medium 4 as well as mounting means 5. These mounting means 5 are here between the holder 2 and the upper part of the mounting plate 3 and are formed by either or not detachable fastening means such as permanent adhesives, clamps, screws or for example a dove-tail detachable coupling between the holder 2 and the sheet 3.
In addition the device 1 is provided with detachable mounting means 6-1, 6-2 between the mounting plate 3 and the abrasive medium 4. The detachable mounting means (not shown in the drawings) may for example comprise metal parts in conjunction with or mixed with one or more magnetic materials. Examples of attracting magnetic materials are iron, iron filings or steel, provided on or in the sheet and/or the medium and possibly in the later to be described support layer 10, all this in order to be able to connect and disconnect the sheet 3 and medium 4 by hand.
In the drawings there is shown detachable mounting means comprising pins 6-1 and apertures 6-2 for inserting and holding tight the pins 6-1 accommodated therein. As shown the pins 6-1 are present on a lower contacting surface 7 of the mounting plate 3, whereas the contacting surface 8 of the abrasive medium 4 facing surface 7 carries the apertures 6-2.
In figs 1A and 1B the apertures 6-2 are apertures which only piers the upper surface 8 of the medium 4, which can thus not be turned upside down and mounted on the sheet 3. This is unless the pins 6-1 pressing on the surface 8 create their own apertures 6-2 therein, which is possible if the medium 4 has at least such surface made from for example cork or a similar suitable material. If mounted on the surface 7 of the sheet 3, the lower sanding surface 9 of the abrasive medium 4 can be made flat or curved, if so wanted, for certain applications such as polishing.
In this and the embodiments next to be described having pins and apertures it is preferred if the pins 6-1 and apertures 6-2 accommodating these pins snugly fit into one another. Mounting and dismounting can then easily take place manually as it is easy to overcome a clamping force between pins and apertures when the medium 4 is applied or removed from the plate 3. Accidental falling off of the medium 4 from the sheet 3 is prevented by the clamping force. The pins 6-1 and apertures 6-2 normally have corresponding cross sections. Examples of suitable cross sections are circular, triangular, squared, trapezium like, multi-edged or the like. The larger the outer contacting surfaces of those pins and apertures is the larger the frictional resistance is, which creates the clamping force, holding the sheet 3 and medium 4 together.
In the embodiments shown in figs. 2A and 2B the apertures 6-2 present in the abrasive medium 4 run through the medium and also open in the lower medium surface 9 thereof. As an alternative if the apertures do not run through the sheet 4 then both opposing surfaces 8 and 9 of the medium 4 may have apertures 6-2. In the part of the apertures 6-2 opening in the lower surface 9 of the sheet 4 dust can collect during the treatment of a surface of an object such as during the sanding or polishing operation.
In the embodiments of figs. 2A and 2B the abrasive medium 4 may have two abrasive opposing surfaces 8, 9. Then the medium 4 can simply be taking off manually from the sheet 3, turned upside down and remount on the pins on surface 7 by aligning and registering the pins and corresponding apertures, and then pushing them together. So the apertures 6-2 are used for mounting sheet 3 and medium 4 and/or for collecting dust while the device 1 is in use. That is the upper end part of such double functioning apertures 6-2 concerned is used for mounting purposes, while the lower end part thereof is used for collecting removed surface material from the surface treated object and later on for removing that material there from. In the case wherein the sheet 3 can be turned around and used so to say again it may be useful to have opposing abrasive outer medium surfaces 8 and 9 of the abrasive medium 4 that have a similar or dissimilar roughness.
In figs. 3A and its encircled detail of fig. 3B the device 1 has the abrasive medium 4 which includes a support layer 10 which lies in between the two possibly both abrasive outer medium surfaces 8 and 9. The support layer 10 may comprise plastic, foam, cardboard, wood, cork or the like, either or not comprising metal and/or magnets. Layer 10 is provided with schematically shown types of apertures 6-2, which may be shallow to only accommodate pins or run through the layer 10 and surfaces 8 and 9 for collecting dust and making reuse possible if turned upside down.
In Figs. 4A and 4B a mounting plate 3 of the device 1 is shown which has one or more, or a circumferential, or possibly an annular tab member 11. The extending member 11 together with a fitting rim 12 of the abrasive medium 4 to be clamped in the member 11 now form the detachable mounting means in a sideways contacting clamped arrangement.
In Figs. 5A and 5B, and 6A and 6B the pins 6-1 of these respective devices 1 are expandable in width which make them capable of clamping in the wider apertures 6-2 of the abrasive medium 4. The pins 6-1 shown in figs 5A (which are known per se) and 5B if inserted in the apertures 6-2 are devised to expand by exerting a manual pressure in upward direction and by exerting a medium pressure in a hollow 13 of the pins 6-1, respectively. The medium can for example be gas or liquid put under pressure by means not shown in the drawings. The expansion in width resulting from the manually applied pressure and the pressurising respectively of the medium in the hollow 13 of the inflatable elastic pins 6-1 creates the clamping thereof in the apertures 6-2.
Figs. 7A, 7B and 7C show a device 1 having a two part mounting plate 3. The two parts 3-1 and 3-2 are manually movable relative to each other under compression of a resilient of elastic member, such as a spring 13 as shown. In the compressed state of the parts 3-1, 3-2 shown in Fig. 7B all the pins 6-1 concerned are in perfect register for insertion in the apertures 6-2. In then uncompressed state as shown in Fig. 7C side flanks 14 of the pins 6-1 are pressed against the side flanks 15 of the apertures 6-2. This creates a detachable holding force between the mounting plate 3 and the abrasive medium 4. In this embodiment the sizes and relative positions of the pins and apertures is less critical, making this device 1 easier to manufacture. In the embodiment as shown have through going apertures the abrasive medium 4 can have two abrasive opposing surfaces 8, 9 making the medium multi usable after reversal.

Claims

A surface treatment device (1) comprising:
- a holder (2) for handholding or coupling with powered tools,

- a mounting plate (3) provided with an abrasive medium (4), and

- mounting means (5) provided between the holder (2) and the mounting plate (3),
characterised in that
the surface treatment device (1) comprises detachable mounting means (6; 6-1, 6-2) provided between the mounting plate (3) and the abrasive medium (4) for detachably holding the abrasive medium (4) on the mounting plate (3).
The device (1) according to claim 1, characterised in that the detachable mounting means comprise pins (6-1) and apertures (6-2) for accommodating and tightening the pins, which detachable mounting means (6-1; 6-2) are provided on contact surfaces (7; 8, 9) between the mounting plate (3) and the abrasive medium (4).
The device (1) according to claim 2, characterised in that the contact surface (7) of the mounting plate (3) is provided with pins (6-1) and the contact surface(s) (8; 9) of the abrasive medium (4) is (are) provided with apertures (6-2), or the other way round.
The device (1) according to claim 2 or claim 3, characterised in that at least some of the pins (6-1) and apertures (6-2) have corresponding cross sections, such as circular, semi-circular, triangular, squared, trapezium like, multi-edged or the like for clamping the mounting plate (3).
The device according to any one of the claims 2-4, characterised in that the corresponding cross sections of the pins and apertures are such that in mounted condition the pins and apertures snugly fit into one another.
The device according to any one of the claims 2-5, characterised in that at least some of the pins (6-1) are hollow pins which are expandable in width by means of a medium pressure exerted in the hollow.
The device according to any one of the claims 1-6, characterised in that the abrasive medium (4) having opposing contact surfaces (8, 9) has at least one abrasive outer contact surface (8; 9).
The device according to claim 7, characterised in that the abrasive medium (4) comprises a support layer (10) having one abrasive outer contact surface (8; 9), or being sandwiched between the two contact surfaces (8, 9).
The device according to claim 8, characterised in that apertures (6-2) end in the support layer (10), or are apertures running through both contact surfaces (8, 9) and the support layer (10).
The device according to any one of the claims 8-9, characterised in that the support layer (10) comprises a reinforcing material such as plastic, foam, cardboard, wood, cork or the like, either or not comprising metal and/or magnets.
The device according to any one of the claims 7-10, characterised in that the two abrasive outer contact surfaces (8, 9) have respective surface roughnesses, which are similar or dissimilar.
The device according to any one of the claims 1-11, characterised in that the detachable mounting means (6; 6-1, 6-2) are constructed as a two part mounting plate (3), which parts are under pressure manually movable toward each other in the plane of the contact surface (7) of the mounting plate (3).
The device according to claim 12, characterised in that the two part mounting plate has a resilient or elastic member mounted between the parts.
The device according to any one of the claims 1-13, characterised in that the detachable mounting means provided between the mounting plate and the abrasive medium comprises a permanent attracting magnetic material, such as iron, iron filings or steel, provided on or in the sheet (3) and/or the medium (4).
An abrasive medium (4) comprising two opposing abrasive outer contact surfaces possibly sandwiching a support layer (10) that comprises a reinforcing material such as plastic, foam, cardboard, wood, cork or the like, either or not comprising metal and/or magnets, whereby through at least one of the contact surfaces (8, 9) apertures (6-2) are running, which end in or run through the support layer (10), if present.