Polishing And/Or Sanding Head as Well as Polishing And/Or Sanding Machine Equipped with This Head

The invention relates to a polishing and/or sanding head for a polishing and/or sanding machine for polishing and/or sanding a surface, comprising:

A disc is understood here to mean both round and ring-shaped discs. For applying the polishing or sanding sheets to the discs, the front of the discs and the back of the polishing or sanding sheets may be provided with interlocking hooks, as is the case with Velcro.

A polishing and/or sanding head according to the preamble of claimis known from CH 652 065 A. This known polishing and/or sanding head has two concentric discs provided with external and internal teeth, respectively, and a number of planet gears between the two teeth. These planetary gears are coupled via a transmission to a central shaft that can be coupled to a driven shaft of a machine. This construction causes the discs to rotate in opposite directions. During polishing or sanding, the polishing and/or sanding head is moved over the surface to be treated. It has been found that the treated surface is not completely smooth, but that there are areas on it that have an appearance different from other parts of the surface.

An object of the invention is to provide a polishing and/or sanding head with which, when used in the same manner as the known polishing and/or sanding head, a more even polishing or sanding result is obtained than with the known polishing and/or sanding head. To this end, the polishing and/or sanding head according to the invention is characterized in that:

Due to the presence of a third disc, which does not make a rotating but an oscillating movement (in two directions at right angles to each other), a smooth surface is obtained on which no areas with a deviating appearance are present.

Of the discs, a first disc is the innermost disc, the second disc is annularly surrounding the first disc, and the third disc is annular and surrounding the second disc. The polishing and/or sanding head can be arranged in such a way that one of these discs can make a circular movement and the other two discs rotate. Preferably, however, the first and second discs are rotatable in opposite directions about their center and the third disc is capable of circular motion. This circular motion means that the disk is oscillable in two perpendicular directions so that each point of this disk makes a circular motion about an imaginary axis, where the distance of each point of this disk to the imaginary axis about which this point moves is for all points equal.

A constructively favorable embodiment of the polishing and/or sanding head is characterized in that:

Preferably, the eccentric has a shaft that is eccentric with respect to the third gear and is coupled to the third gear and to the third disc. The shaft is preferably mounted on the third gear or on the third disc and is rotatably provided in an opening in the third gear and in the third disk respectively.

The polishing and/or sanding head preferably has a frame wherein the at least one planetary gear and the at least one third gear are rotatably connected to the frame.

The invention also relates to a polishing and/or sanding machine comprising a drive provided with a driven shaft, as well as a polishing and/or sanding head according to the invention, of which the coupling is coupled to the driven shaft.

show an embodiment of the polishing and/or sanding head according to the invention in top, bottom and side views, respectively. The polishing and/or sanding headhas a frameand three discs,andmovably coupled to the frame. Of these discs, a first discforms a round inner disc and a second discis annular and surrounds the first disc. These first and second discsandare concentric and rotatable in opposite directions about their common center. The third discis also annular and is provided around the second disc. This third discis not rotatable but can make a circular movement about an imaginary axis. The discs-are provided with a front sideA-A, which faces the surface to be treated during operation and on which a polishing or sanding sheet can be applied.

Gears are present at the rearB-B of the discs-. Inthe polishing and/or sanding head is shown in cross section along the lines I-I and II-II respectively indicated inand inthe polishing and/or sanding head is shown in an exploded view. The transmissions formed by the gear wheels between the discs will be explained below on the basis of these figures. Mounted on the back sideB of the first discis a first gear wheelwhich is provided with external teethA. Mounted on the back sideB of the second discis a second annular gearwhich has an internal toothingA and an external toothingB. Between the external gearingA and the internal gearingA are three planet gearsprovided with external gearingA.

The gears-form a first gear that is present between the first and second discs and causes the discs to rotate in opposite directions. The planet gearsare mounted in frameby means of bearing blocks. Furthermore, three third gearsprovided with external gearsB are mounted in frameby means of bearing blocks. These third gearsform a second transmission with the second gear. Pinsare mounted on these third gears, which are located away from the center of the gearsand form an eccentric. These pins are rotatably present in openingsin the third discand ensure that this third discmakes an eccentric movement whereby his third discdoes not rotate about its center.

The first gear wheelis coupled to a coupling piecewith which this gear wheel can be coupled to a driven shaft of the polishing and/or sanding machine. Also attached to the frame is a handlewith which the polishing and/or sanding head can be moved over the surface to be treated.

Although the invention has been elucidated in the foregoing with reference to the drawings, it should be noted that the invention is by no means limited to the embodiment shown in the drawings. The invention also extends to all embodiments deviating from the embodiment shown in the drawings within the scope defined by the claims.