AIR COOLING FILTER FOR ELECTRIC MOTOR AND RELEVANT MOUNTING SUPPORT

Abstract

A cooling air filter for an electric motor, includes a filter with a planar shape and minimum dimension so as to cover the area of the slits of a covering casing of a fan for an electric motor for which it is intended; and the filter is housed in a support which is fixed in a steady and removable way on the surface of the casing; the support having a frame-like structure from which at least two arms extend, which are diametrically opposite in the frame-like structure, and which are provided at their end with fixing and gripping means of the arms on the casing itself; the fixing means being configured for the fast detachment from and hooking onto said casing.

Claims

1. A cooling air filter for an electric motor built according to the standardization regulations, comprising: a filtering material with a planar shape and minimum dimension so as to cover the area of the slits of a covering casing of a fan, operating in suction for the cooling of the electric motor for which the filter is intended; wherein said filtering material is housed in a support which is fixed in a steady and removable way on the external surface of the casing; wherein the support includes a frame-like structure, with a centering edge of the filter material, from which at least two arms extend, diametrically opposite in the frame-like structure, and are foldable and lie on the external curved surface of the fan casing; wherein said arms are provided with fixing and gripping means of the arms on the fan casing itself and said frame-like structure and of the filtering material are held against the slits; and wherein the steady and removable fixing means is configured for the fast detachment from and hooking onto said external curved surface of the fan casing.

2. A cooling air filter, according to claim 1, wherein said steady and removable fixing means comprise said arms which are provided with a fabric with fabric gripping microhooks which engages in a portion of fabric glued in a fixed way on the surface of the external curved surface of the fan casing for the cooling fan of electric motor.

3. A cooling air filter, according to claim 1, wherein said steady and removable fixing means comprise said arms which are provided with a seat for a permanent magnet within which a permanent magnet is housed, in such a way as to perform the grip by magnetic attraction on external curved surface of fan casing of ferromagnetic material, for the cooling fan of electric motor.

4. A cooling air filter, according to claim 1, wherein said steady and removable fixing means comprise said arms which are foldable on the surface of the side of the casing and have a sufficient length for the grip of the gripping means applied on the cylindrical surface of the casing.

5. A cooling air filter, according to claim 4, wherein said steady and removable fixing means comprise the elastic extension made on an elastic element, applied at the end of one arm, which in itself does not have elasticity in extension; said elastic element being provided with a hook at the end engaging on the edge of the curved fan casing (6) of the electric motor.

6. A cooling air filter, according to claim 4, wherein said arms are foldable on the surface of the side of the curved fan casing and are kept on the side of the casing by a ring-shaped elastic element which engages in grooves which are present in the end of each arm.

7. A cooling air filter, according to claim 4, wherein said arms, besides being foldable, are also extensible, that is to say, they are provided with an elastic extension and a hook at the end engaging on the edge of the curved fan casing of the electric motor.

8. A cooling air filter, according to claim 1, wherein at least two different gripping means are present simultaneously in the body or end of each of the arms for steady and removable positioning, in such a way as to allow the user to select which of said gripping means to use.

9. A cooling air filter, according to claim 1, wherein at least the frame-like support with centering edge are made of transparent material.

10. A cooling air filter, according to claim 1, wherein the ends of the arms have a tapered shape to facilitate grasping by the user's fingers.

Description

SHORT DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 shows a schematic perspective view of a filter support according to the invention before being mounted on the casing that covers the cooling fan in an electric motor;

[0021] FIG. 2 shows a schematic perspective view of the support of FIG. 1, here mounted on the metal casing of a generic electric motor in which the positioning of the ends of the arms occurs by a magnetic action;

[0022] FIG. 3 shows a schematic plan view of a filter support used in the previous Figures;

[0023] FIG. 4 shows a schematic sectional view taken along the line IV-IV of FIG. 3:

[0024] FIG. 5 shows a schematic enlarged view of the portion V of the section of FIG. 4;

[0025] FIG. 6 shows a schematic enlarged view of the portion of FIG. 3;

[0026] FIG. 7 represents a schematic enlarged view in a limited perspective in the direction VII of FIG. 1;

[0027] FIG. 8 shows a schematic view in lower perspective, that is to say, the casing side of the electric motor, of the filter support of FIG. 1;

[0028] FIG. 9 shows a schematic side view of a filter support, according to the invention, of a specific embodiment with elastic grip of the edge of a casing for an electric motor;

[0029] FIG. 10 shows a schematic perspective view of a cooling air filter for an electric motor with its support, according to the embodiment of FIG. 9;

[0030] FIG. 11 shows a schematic perspective view of a cooling air filter of an electric motor according to the embodiment of FIGS. 1-8, with its support and an elastic element for fixing the arms of the support;

[0031] FIG. 12 shows a schematic perspective view of the support of FIGS. 1-8, here mounted on the metal casing of a generic electric motor in which the positioning of the end of the arms occurs by the action of a ring-shaped elastic element, which keeps the arms of the support in position;

[0032] FIG. 13 shows a schematic perspective view of a cooling air filter of an electric motor according to the embodiment of FIGS. 1-8, with its support and added extensible elastic fixing elements provided with an end hook, one for each arm of the support;

[0033] FIG. 14 shows a schematic perspective view of the support of FIGS. 1-8, here mounted on the casing of a generic electric motor in which the fixing of the arms occurs at the ends of the arms by the action of an elastic element, each arm being provided with a hook, which hooks the arm on the edge of the protection casing of the fan of the electric motor.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0034] In FIGS. 1 to 7 a support 1 for an air filter comprises a frame-like support 2, advantageously ring-shaped, provided with a centering edge 3 of a filter 4, advantageously disc-shaped; from said edge 3 at least two arms 5 extend in radial opposition, foldable and opposite to each other, to follow the shape of the covering casing 6 of the fan of an electric motor 7, the ring-shaped support 2 is centred on the front C of the casing in correspondence of the air suction slits of the cooling fan, the fan and slits not being shown: each foldable arm comprises at its end 8 gripping means 9 for the positioning of said end on the side F of the casing 6 of the electric motor 7. The gripping means 9 of the arm consist of an interlocking seat 10 for a permanent magnet 11, a groove 12 for receiving an annular fixing means 13, advantageously an elastic ring, visible in FIGS. 11 and 12, which is inserted in said grooves and keeps the ends of the foldable arms 5 against the casing 6. To complete the end 8 there is a tapered shape 14, to facilitate grasping by the fingers of a maintenance-operator to allow him/her to position the end of the foldable arm correctly.

[0035] In FIGS. 4, 5 and 8 one can also see a connection hole 15 for an elastic element 16, visible in FIGS. 13 and 14, as a further element and mounting variant of the gripping means of a foldable arm 5 on a casing 6 and in the absence of a permanent magnet 11, or if the casing is not ferromagnetic, in the absence of an annular means 13, or elastic ring. Said elastic element 16 being made up of a male element 17, intended for the coupling in the hole 15 and of a body 18, for joining said male element with a hook 19, connected with a rubber band 20 to said body 18. The hook 19 grips on the terminal edge 21 of the casing 6, in such a way as to keep the foldable arm 5 in position and, as a consequence, also the ring-shaped frame-like support 2, with the filter 4.

[0036] In FIGS. 9 and 10, of a specific embodiment, a frame like support 22, advantageously ring-shaped, has a retaining edge 23 of a filter 24, advantageously disc-shaped, and is provided with foldable and elastic arms 25 ending with a hook 26, bent for the grip of an edge 21 of a casing 6 of an electric motor, similarly to what is shown in FIG. 14. Each foldable and elastic arm 25 has a bellows configuration 27, in such a way as to obtain the extension elasticity of the hook 26, for the elastic extension by deflection of the material of which it is made, with respect to the frame-like support 22 and grip on said edge 21 of the casing 6. Moreover, in the absence of a hook 26 or in replacement of the latter at the end 28 of one arm 25, or even in coupling with an end 8 of one arm 5, one can apply a fabric with fabric gipping microhooks (trade name Velcro) which engages in a portion of fabric glued in a firm way on the surface of a casing 6 of a cooling fan for an electric motor (embodiment not shown).

[0037] The frame-like support 2 or 22 and the retaining edge of the filter 4 or 24 is advantageously made of transparent material, to be able to see the progressive clogging of the filter with the fine dust and with the spraying of liquids: a greater clogging is detectable from the greater penetration, and consequent blackening of the material of the filter, in the thickness of the filter itself. In this way the user can decide whether to continue to use the filter or replace it.

[0038] The use of the support for the cooling air filter for an electric motor is clear from the enclosed figures. The filter support is thus a new and practical means for positioning a filter 4 or 24, which is disc-shaped only to imitate the ventilation slits of a casing 6, but which can also be square, rectangular, triangular, hexagonal or of another shape, and by the use of the support according to the present invention it is easily mounted on a casing 6 of a generic electric motor 7. The mounting on an electric motor is made on any constructive form of motors, with the only necessary limit that the size of the filter 4 or 24 is not much greater than the size of the slits of the protection casing of the cooling fan of the electric motor. Obviously the size of the filter should be equal to the width of the slits in the casing as well as the openings 30 in the support 2 or 22.

[0039] By the proposed embodiments of the foldable arms of the support the grip is performed in any efficient way: with magnetic means, that is to say, with the permanent magnet 11 housed in the seat 10, which holds the magnet in the end 8 of the arm 5, and, when drawn close to the ferromagnetic external surface of a casing 6, is able to fix the position of the end 8 of the foldable arm 5. Similarly, the presence of a groove 12 in the end of the arm allows to house in it an annular means 13, which can consist of a flexible and extensible elastic ring, or of a broken and flexible metal ring, made of material for springs, in such a way that it behaves like an elastic ring, which holds the ends 8 where it is inserted against a casing 6, when the latter is not ferromagnetic or does not have the permanent magnets.

[0040] Thus, in the embodiment with the hook 19 or 26, the end of one arm 5 or 25 is fixed to the edge 21 of a casing 6 of an electric motor, slightly tensioning the elastic part of the arm: be it the bellows part 27 or the rubber band part 20 to hook said hook to the edge 21 of the casing after tensioning said elastic part.

[0041] The advantages in the use of a cooling air filter for an electric motor can be summarized in the practicality of mounting and following maintenance of each of the described embodiments, either by magnetic fastening, or by fastening with an annular elastic means or with a tensioned elastic means. Last but not least, also the embodiment with the microhooks gripping element (trade name Velcro) is advantageous, in the specific need to apply and detach several times, in the expected life of the filter support, and replace the filter 4 or 24 itself.

[0042] The realization of said fixing means can occur individually on a filter support, that is to say, the support being provided during construction with only one of said fixing means, but more advantageously two or more of said fixing means are combined during construction on one single support 1, as depicted, in such a way as to leave the user free to select which of the fixing means to use in the application of the cooling air filter for electric motor he/she wants to carry out.

[0043] Obviously, to the above-described cooling air filter for an electric motor and related mounting supports a person skilled in the art, in order to meet specific and contingents needs, can make several changes, which will all be included within the scope of protection of the present invention as defined by the following claims. Obviously, although less advantageously, a support for a cooling air filter can be applied to electric motors whose shape is not necessarily cylindrical, it being possible, as stated in the text, to shape the frame-like support with a perimeter having a varied shape and at least two radially opposite arms 5. Moreover, the length of the arms 5 being able to be limited and the dripping means 9 gripping directly on the front C of the casing 6 of an electric motor, optionally with a permanent magnet, if the casing is ferromagnetic, or even with a fabric having fabric gripping microhooks (trade name Velcro) which engages in a portion of fabric glued in a steady way on the surface of the casing. In both the embodiments, which have just been described, there always remaining the steady and removable fixing of the frame-like support, when required, for the replacement of the filtering material constituting the filter.