MAGNETIC DEBRIS SEPARATOR IN A BRAKE HOUSING

Abstract: Method in brake apparatus of vehicles, which brake apparatus consists at least of a brake organ as well as a retardation piece, that has one or several brake surfaces (3). Impurities loosening during braking from a brake apparatus having an essentially closed internal space, such as a drum brake or like, and gathering into the brake apparatus, is being collected by means of an electromagnetic collector (12). The invention relates to a device in brake apparatus of vehicles functioning according to the method, also.

Description: Magnetic debris separator in a brake housing This invention relates to a method and device in brake apparatus of vehicles, which consists at least of a brake organ as well as a retardation piece, that has one or several brake surfaces. Nowadays brake apparatuses are being used in vehicles, that consist primarily of a retardation piece, that has at least one brake surface, as well as preferably of two brake organs, in which there has been arranged at least one friction surface. The retardation piece has been attached to the axis of the wheel of the vehicle by means of bearings. The wheel is being attached preferably by bolts to wheel fastening means, that has been formed to the retardation piece. To achieve a brake effect at least a part of the friction surfaces of the brake organs is pressed against the brake surface of the retardation piece by influence of power effect due to pushing a brake pedal or like, whereby mutual friction of the brake surface and the friction surface of brake organ brings out slowing down of rotation movement of the wheel being connected to the retardation piece. Brake apparatuses being used in vehicles are mostly disc brakes and/or drum brakes. In disc brakes the brake organ comprises usually two brake pieces. As a retardation piece in disc brakes usually a brake disc is being used, in which the brake surface consists usually of at least a part of the side surfaces of the brake disc. As the brake organ in drum brakes preferably two brake shoes are being used and as a retardation piece a brake drum, in which at least a part of the inside surface of the outer periphery of the brake drum acts as the brake surface. The mutual friction of the brake surface and the friction surface of the brake organ depends among other things on evenness and cleanness of the brake surface and the part of the friction surface of the brake organ being pressed against the brake surface and magnitude of power pushing the surfaces against one another. The shape of brake surfaces of vehicles moving particularly in main roads may vary greatly depending on climate circumstances, salts being used in roads, surface damages caused by dampness as well as wearing. Use of the brakes in road driving is usually less when compared to city driving. In this case moisture as well as impurities may be formed at the brake surfaces decreasing brake effect. Wearing of unclean brake surfaces does not happen evenly throughout the whole area of the brake surfaces but varies in different parts, which furthermore decreases brake effect. In addition to that dampness causes rust to the brake surfaces, in which case duration of the brake surface is decreased, also. An uneven brake surface increases wearing of the friction surface of the brake organ during braking, also, whereby replacement interval of the brake organ is shortened. Small material particles are being loosened by influence of friction effected by braking. Particularly in drum brakes these material particles tend to gather inside the brake drum forming possibly rouhgnesses in the brake surface, whereby the brake surface must be cleaned and ground even after certain time intervals. As a consequence of the above disadvantages the brakes must be serviced more often than it would be necessary, if wearing of the brake surfaces would happen evenly within the total area of the brake surface. Rust being formed to the brake surfaces must also be removed or the whole retardation piece must be replaced with a new one. Under disadvantageous circumstances the replacements must be carried out even with 30000 - 40000 km intervals. Repairing of the brake surfaces takes time as well as increases service costs of vehicles. In patent document DE 4 021 567 there has been presented a scraper suitable for this kind of purpose, which, when being used in connection with a drum brake does not, however, improve the situation decisively, because inspite of the scraper loose material still exists inside the brake drum. In certain situations material may be attached to harmful points e.g. due to freezing and the like sedimentation in a way, that e.g. the type of scraper being represented is not any more able to remove the same from the friction surfaces. It is the aim of the invention in question to eliminate the disadvantages mentioned above as well as to improve the level of techniques prevailing in the field. To achieve this aim the invention is primarily characterized in, that impurities loosening during braking from a brake organ, such as brake shoes and a retardation piece, such as a brake drum of a brake apparatus, that comprises an essentially closed internal space, such as a drum brake or like, and gathering into the brake apparatus, is being collected by means of an electromagnetic collector. With the invention significant advantages are achieved. By exploiting the method and device according to the invention the service interval of brakes may be increased and improve duration of the brake surfaces, because clean brake surfaces wear more evenly, which is why operating time of the same increases as well. Because the brake surfaces of brake apparatuses being equipped with the device according to the invention remain drier in wet circumstances than the brake surfaces of nowadays brake apparatuses, formation of rust to the brake surfaces is decreased. Due to lenghthened service interval and improved duration of the brake surfaces cost savings are achieved, also. The method according to the invention improves safetyness as well, because functioning of the brakes is more reliable. The permanent magnet according to the invention may easily be installed removably to the brake plate or brake drum, in which case it may be removed, cleaned and once more reinstalled during usual service measures, such as in connection with regular servicing measures or like. It has been found during tests in practice, that material gathering inside the drum brake in question is very magnetic, that is why essentially all of the loose material inside the brake drum is collected to the permanent magnet. By means of an ordinary permanent magnet all the loosened material inside the brake drum during one service interval may easily be collected. The invention is described in greater detail with reference to the enclosed drawings in the following description, in which fig. la shows a simplified side-view of a construction of an advantageous embodiment of the invention being installed to a disc brake, fig. lb shows an embodiment according to fig. 1 as a cross section along line A - A, and fig. 2 shows a construction of an other embodiment of the invention being installed to a drum brake . The invention relates to a method in brake apparatus of vehicles, which consists at least of a brake organ as well as a retardation piece, that has one or several brake surfaces. Impurities loosening during braking from a brake organ, such as brake shoes 13 and a retardation piece, sucha as a brake drum 2 of a brake apparatus, that comprises an essentially closed internal space, such as a drum brake or like, and gathering into the brake apparatus, is being collected by means of an electromagnetic collector 12. As an advantageous embodiment of the method impurities from the brake surfaces 3 of the brake apparatus are being exhausted preferably by means of one or several mechanical scrapers 5, that press at least partly against the brake surface 3 of the brake apparatus. As an advantageous embodiment impurities are being collected by means of the collector 12, such as a permanent magnet or like essentially from the bottom part of the brake apparatus, preferably essentially in connection with the scraper 5. The device according to the instruction comprises an electromagnetic collector 12 to collect impurities loosening during braking from e.g. brake shoes 13 and the brake drum of 2 of a drum brake, and collecting into the brake apparatus . As an advantageous embodiment the permanent magnet 12 is arranged essentially at the bottom part of the drum brake and advantageously in connection with the scraper 5. In fig. la to the axis of the wheel 1 of the vehicle there has been connected a retardation piece 2 e.g. by means of a bearing 4. The brake surface 3 of the retardation piece is formed in this embodiment preferably of the side surfaces 3a and 3b of the retardation piece, against which there exists an essentially U-shape scraper 5. The bottom part of the U-shaped is being placed against the periphery surface 6 of the retardation piece 5. When the retardation piece 2 rotates around the rotation centre of the same, the scraper 5 cleans and dries the brake surfaces 3a and 3b as well as the periphery surface 6 of the retardation piece 5. The mutual surface pressure of scraper 5 and the brake surfaces 3a and 3b may be rather small, in which case the scraper 5 does not essentially wear the brake surfaces 3a and 3b. The scraper 5 has been attached flexibly close by the brake surfaces, preferably by means of a lever arrangement, that consists of a flexible attaching arm 7 and e.g. spring effected damping means 15. In this case a minor eccentricity or distortion of the retardation piece does not significantly harm clearing of the brake surfaces. The first end 8 of the attaching arm has been fastened to the scraper bar 5 and the other end 9 of the attachment arm has been fastened by joints to the non-rotating structure of the brake apparatus, such as to a brake saddle 11 supporting the brake pieces 10. It is advantageous to place the scraper 5 above the rotation centre of the retardation piece, in which case the bottom part of the U-shaped scraper 5 follows at least partly by influence of gravity the periphery surface of the retardation piece. Shaking of the scraper 5 may furthermore be dampened by means of the dampening means 15 belonging to the lever arrangement, the first end of which is being attached to the attaching arm 7 and the other end to the non-rotating structure of the brake apparatus. A flexible, jointed attachment structure makes the cleaning effect of the scraper more efficient as well as keeps a worn scraper in better shape, also. By shaping the scraper 5 advantageously gathering of impurities to the uniting point of the scraper 5 and brake surface 3 may be decreased. In the embodiment shown in fig. 2 the scraper 5 has been mounted against the brake surface 3 of the retardation piece 2, in which case, when the retardation piece, that has been installed rotatively to the axis 1 of the wheel of the vehicle, rotates around the rotation centre of the same, the scraper 5 cleans the brake surface 3. The lever arrangement has been exploited in this embodiment as well, to fix the scraper 5 to the structures of the vehicle, which consists of an essentially L-shaped attaching arm 7 and the dampening means 15. The attaching arm 7 has been connected by the other end 9 of the same to the non-rotating structure of the brake apparatus, such as to a brake plate 14. It is advantageous to place the scraper 5 in a way, that the scraper follows at least partly by influence of gravity the periphery surface of the retardation piece. As a shaking damper there exists a dampering means 15, that has been attached in connection with scraper 5 and the non-rotating structure of the brake apparatus . Material of the scraper 5 may be chosen among other things on grounds on the operating circumstances. The structure of the scraper may be e.g. elastic or it may consist of several brushes. The shape of the scraper is preferably U-shaped when being used in disc brakes and in drum brakes an elongated rod, that is being placed essentially crosswise in respect to the rotation movement, but also other shapes may be used. The scraper may be formed of several parts as well and the parts may be placed at differing points of the brake surface.

Claims: Claims 1. Method in brake apparatus of vehicles, which consists at least of a brake organ as well as a retardation piece, that has one or several brake surfaces (3), characterized in, that impurities loosening during braking from a brake organ, such as brake shoes (13) and a retardation piece, such as a brake drum (2) of a brake apparatus, that comprises an essentially closed internal space, such as a drum brake or like, and gathering into the brake apparatus, is being collected by means of an electromagnetic collector ( 12) . 2. Method according to claim 1, whereby impurities from the brake surface ( 3 ) of the brake apparatus are being exhausted preferably by means of one or several mechanical scrapers (5), that press at least partly against the brake surface ( 3 ) of the brake apparatus, characterized in, that impurities are being collected by means of the collector (12), such as a permanent magnet or like essentially from the bottom part of the brake apparatus, preferably essentially in connection with the scraper (5). 3. Device in brake apparatus of vehicles, which brake apparatus consists of at least a brake organ as well as a retardation piece, that has one or several brake surfaces (3), characterized in, that the device comprises an electromagnetic collector (12) to collect impurities loosening and gathering during braking from a brake organ, such as brake shoes (13) and retardation piece, such as brake drum (2) of a brake apparatus, that comprises an essentially closed internal space, such as a drum brake or like. 4. Device according to claim 3 , which device has preferably one or several mechanical scrapers (5), that press at least partly against the brake surface (3) of the brake apparatus, to collect impurities from the brake surface (3) of the brake apparatus, characterized in, that the collector (12), such as a permanent magnet or like is arranged essentially at the bottom part of the brake apparatus, preferably in connection with the scraper (5).

Inventors: TAIPALE ASKO, TAIPALE, ASKO
Applicants: ASKO TAIPALE OY, TAIPALE ASKO, TAIPALE, ASKO
Application year: 1997
Main classification: B60T17
IPC codes: B03C1, F16D51, F16D55, F16D65