DESCRIPTION

The present invention relates to a filter holder of the type adapted to be attached to a suction grille of a fan. In particular, the filter holder of the present invention is designed for use in extractor and/or filter hoods for domestic use. Of course, as further explained herein, the filter holder of the present invention may have more general applications.

A filter holder of the type adapted to be attached to a suction grille of a fan is known in the art. This suction grille has a substantially circular shape and a center axis of symmetry. Sometimes, the suction grill may have a slight taper, i.e. with a central zone extending outwards with respect to a peripheral zone.

A cylindrical wall is fixed proximate to the central axis of the suction grille and extends outwards from the grille. Three angularly spaced projections are placed on the distal edge of the wall, and extend outwards from the cylindrical wall, i.e. parallel to the suction grille.

The filter holder of the prior art, which is designed to be attached to the above discussed suction grille, has a base grille. This base grille has a central zone which is configured to be arranged along the center axis of the suction grille. A holding volume is partially defined by said base grille and configured to receive filter material.

For fixation to the suction grille, the filter holder of the prior art comprises a coupling ring, having a greater diameter than the cylindrical wall of the suction grille. This coupling ring is located at the central zone and has three angularly spaced hooks, which are adapted to hold the projections that are fixed to the suction grille. When the user wants to couple the filter holder, he/she fits the coupling ring onto the cylindrical wall, introducing the hooks between the projections. Once the filter holder is in its position, it is rotated for the hooks to fit between the projections and the suction grille. As a result, the projections retain the hooks and prevent the filter holder from being pulled out by exerting a force along the center axis.

In order to be pulled out, the filter holder is rotated in the reverse direction to release the hooks from their respective projections and moved away along the center axis.

Disadvantageous^, the filter holder of the prior art is difficult to pull out, especially when it is deeply tightened and additional components around the filter holder prevent it from being properly grasped.

SUMMARY OF THE INVENTION

Therefore, the technical purpose of the present invention is to provide a filter holder of the type adapted to be attached to a suction grille, that can obviate the above discussed prior art drawbacks.

In particular, the object of the present invention is to provide a filter holder of the type adapted to be attached to a suction grille that can facilitate the pull-out operation.

The aforementioned technical purpose and objects are substantially fulfilled by filter holder of the type adapted to be attached to a suction grille, that comprises the technical features as disclosed in one or more of the accompanying claims.

In particular a filter holder of the present invention is adapted to be attached to a suction grille of a fan. This suction grille has a center axis and retaining means proximate to the center axis.

The filter holder comprises a base grille, which is adapted to face the suction grille and has a central zone configured to be arranged along the center axis. A holding volume is partially defined by said base grille and configured to receive filter material.

Coupling means are located at the central zone. These coupling means are configured to engage on the retaining means of the suction grille. The coupling means have a seat.

The filter holder further comprises a release member adapted to fit into the seat and configured to engage the suction grille on said retaining means. This release member is configured to push the base grille away from the suction grille, disengage the coupling means from the retaining means and disconnect the base grille from the suction grille.

This device solves the technical problem in that the release member can exert a force that is in itself sufficient to remove the filter holder. Therefore, the filter holder need not be rotated relative to the suction grille, which avoids the need to grasp the filter holder to remove it.

LIST OF DRAWINGS

Further features and advantages of the present invention will result more clearly from the illustrative, non-limiting description of a preferred, non-exclusive embodiment of a filter holder of the type adapted to be attached to a suction grille, as shown in the annexed drawings, in which:

Figure 1 is a perspective view of a filter holder of the present invention, when attached to a suction grille;

Figure 2 is a perspective view of a suction grille;

Figure 3 is a perspective view of a detail of the grille of Figure 2;

Figure 4 is a perspective view of a detail of filter holder of Figure 1 ;

Figure 5 is a sectional side view of the filter holder of Figure 1 when attached to the grille of Figure 2;

Figure 5a is a magnified detail of the view of Figure 5; and

Figure 6 is a sectional side view of the filter holder of Figure 1 when attached to the grille of Figure 2, and as it is being released. DETAILED DESCRIPTION

Referring to the accompanying figures, numeral 1 designates a filter holder of the type adapted to be attached to a suction grille 100 of a fan.

The suction grille 100, which is not part of the present invention per se, is substantially circular and has a center axis "A". Retaining means 101 for locking the filter holder on the grille 100 are located proximate to the center axis "A". Further details about the retaining means 101 will be provided hereinbelow.

The filter holder 1 comprises a base grille 2, which is adapted to face the suction grille 100. This base grille 2 has a central zone 2a configured to be arranged along the center axis "A" of the suction grille 100. In the preferred embodiment, the base grille 2 has a substantially circular plan shape which, when the filter holder 1 is stably attached to the suction grille 100, is centered on the center axis "A”, although the base grille 2 may have any shape in alternative embodiments. Reference will be often made herein to a circular or axially symmetric shape of the base grille 2 without prejudice to the general scope of the invention.

The filter holder 1 comprises an outer wall 5, which extends transverse, and particularly perpendicular to the base grille 2. This outer wall 5 extends from an outer perimeter of the base grille 2.

A holding volume 3 is partially defined by the base grille 2. This holding volume 3 is also partially defined by the aforementioned peripheral wall 5, and is configured to receive the filter material which, by way of example, is activated carbon.

More in detail, the filter holder 1 comprises a plurality of ribs 6, i.e. radial and transverse ribs. These ribs 6 have the purpose to stiffen and support the base grille 2.

Coupling means 4 are located at the central zone 2a of the base grille 2. These coupling means 4 are configured to engage on the aforementioned retaining means 101 of the suction grille 100.

In particular, the coupling means 4 comprise at least one hook 9, which is adapted to engage in snap-lock fashion the retaining means 101, when the base grille 2 is pushed against the suction grille 100 with a force directed along the center axis "A". The retaining means 101 have an abutment surface 102, which is adapted to receive the coupling means 4, in particular the hook 9.

As shown for example in Figure 5a, the coupling means 4 comprise a pair of hooks 9, which extend circumferentially around the center axis "A". The retaining means 101 comprise a plurality of abutment surfaces 102, which are placed at the same distance from the center axis "A". When the filter holder 1 is applied to the suction grille 100, the hooks 9 expand due to the compression exerted by the projections 102 and then spring back onto the projections 102 and retain them firmly.

It shall be noted that the coupling means 4 have a seat 8. Such seat 8 is defined by an inner wall 10 which surrounds the center axis "A" when the fdter holder 1 is coupled to the suction grille 100.

According to the present invention, the filter holder 1 further comprises a release member 7, which is adapted to fit into the seat 8. This release member 7 is configured to engage the suction grille 100 on the retaining means 101. The release member 7 has the purpose to push the base grille 2 away from the suction grille 100, to disengage the coupling means 4 from the retaining means 101 and disconnect the base grille 2 from the suction grille 100.

As shown for example in Figure 4, the release member 7 comprises a pin 11, which is configured to be arranged transverse, particularly perpendicular to the center axis "A". This pin 11 is further configured to be retained in the seat 8, thereby allowing the release member 7 to rotate. For this purpose, the seat 8 comprises a pair of diametrically opposite openings 8a. Each opening 8a accommodates a respective end of the pin 11.

The release member 7 further comprises a cam 12 which is fixed to the pin 11. This cam 12 is configured to be pressed against the suction grille 100, in particular when the portafilter 1 is being attached thereto. The cam 12 is adapted to rotate with the pin 11 to push the base grille 2 away from the suction grille 100.

More in detail, the cam 12 has an outer surface 13 which, in operation, is pressed against the suction grille 100. This outer surface 9a has a central portion 13a and at least one peripheral portion 13b. In the embodiment as described above, the outer surface 13 has a single central portion 13a between a pair of peripheral portions 13b.

It is worth noting that the central portion 13a is situated at a first distance from the pin 11 and is configured to contact the suction grille 100 when the coupling means 4 are engaged on the retaining means 101. Each peripheral portion 13b is placed at a second distance from the pin 11. The peripheral portions 13b are designed not to contact the suction grille 100 when the coupling means 4 are engaged on the retaining means 101 but may contact the suction grille 100 upon rotation of the pin 11.

It shall be noted that the second distance is greater than the first distance. As a result, when the cam 12 rotates, upon rotation of the pin 11, the filter holder 1 is pushed upwards, and forces the hooks 9 to expand and release the abutment surfaces 102.

It shall be noted that the release member 7 comprises a grip portion 14, which is particularly fixed to the pin 11 and designed to be grasped by a user. This grip portion 14 is opposite to the cam 12 with respect to the pin 11. Advantageously, this will allow the user to act on the grip portion 14 to cause the pin 11 and the cam 12 to rotate and to disconnect the filter holder 1.