Vacuum cleaner nozzle

Abstract: This invention relates to a vacuum cleaner nozzle. The nozzle comprises a nozzle body (10) having a nozzle opening (13) facing the surface to be cleaned and one or several scraper blades each comprising a single, strip shaped piece (16), made from rubber, plastic or some other elastic material. The blade has a first edge part (18) resting on said surface (19) and a second opposite edge part which is secured in a holder (17) or the like in the nozzle body and whose distance (A) from the surface is mainly constant when the scraper blade is moved forwards or rearwards on a hard surface. The length of the piece (16) extending towards the surface from the holder under free conditions is larger than said distance (A) so that the first edge part (18) during said movement will trail behind the holder seen in the direction of movement of the nozzle. The piece (16) has such a shape and such properties that when the direction of movement of the nozzle is reversed it serves as a soft spring for forces which from the surface (19) are applied on the first edge part (18) towards the holder (17).

Description: This invention relates to a vacuum cleaner nozzle comprising a nozzle body having a nozzle opening facing the surface to be cleaned, one or several scraper blades each comprising a single, strip shaped piece, made from rubber, plastic or some other elastic material and having a first edge part resting on said surface and a second opposite edge part which is secured in a holder or the like in the nozzle body and whose distance from the surface is mainly constant when the scraper blade is moved forwards or rearwards on a hard surface, the length of the piece extending towards the surface from the holder under free conditions being larger than said distance so that the first edge part during said movement will trail behind the holder seen in the direction of movement of the nozzle Nozzles of the type described above are previously known. These nozzles which are used on soft as well as hard surfaces comprise a bottom plate facing the surface and have an elongated nozzle opening extending perpendicular to the direction of movement of the nozzle. The nozzle is supported on a hard surface by means of several wheels which with regard to flow conditions define an optimal distance between the nozzle opening and the surface. Behind the nozzle opening and parallel with it there are one or several rubber blades. These blades have a free length extending from the bottom plate towards the floor the length being somewhat larger than the distance between the surface and the plate. Such blades are used to convey dirt on a hard surface when moving the nozzle forwards but they do not hinder the movement of the nozzle on a soft surface. Since the extending free length of the rubber blade is larger than said distance the rubber blade will be somewhat curved when being in touch with the surface and its lower edge will trail with respect to the support point of the scraper blade in the nozzle. If the scraper blade shall serve its purpose it has to be comparatively stiff so that the dirt really is conveyed by the scraper blade when the nozzle is moved on a hard surface. However the use of a scraper blade also means a disadvantage since the scraper blade when the nozzle is moved on a surface will lift the nozzle in the turning positions. This depends on that the scraper blade when the nozzle is moved in one direction is first curved at one side but when reaching a turning position it will be straightened out thereby pressing the nozzle upwards before the scraper blade is then curved towards the other side when the nozzle is moved in the opposite direction. There are also nozzles, see for instance GB-A-2014437, which are provided with thread pickup strips. The purpose of this invention is to achieve a scraper blade which does not have the drawback described above but which can be displaced in the turning positions instead of lifting the nozzle. This is achieved by a nozzle as defined in claim 1 and in the depedent claims. An embodiment of the invention will now be described in detail with reference to the accompanying schematic drawing on which Fig. 1 in a plan view shows the bottom side of a vacuum cleaner nozzle in which the scraper blade is fastened, Fig. 2 shows in a vertical section the scraper blade when the nozzle is moved in a certain direction on a surface, Fig. 3 shows the same section when the nozzle is in a turning position whereas Fig. 4 shows the same section when the nozzle is moved in the opposite direction. As appears from Fig. 1 the nozzle body 10 comprises a bottom plate 11 on which several distance means in the form of wheels 12 or low friction surfaces are arranged . The nozzle body has an elongated nozzle opening 13 with a centrally arranged inlet 14 for the air which flows into the nozzle and which is transported to a tube shaft, not shown, which is connected to the nozzle and to the vacuum cleaner. The wheels 12 are fastened to the nozzle body 10 in such a way that a slot is created between the nozzle opening 13 and a hard surface the distance being so optimized that suitable flow conditions are achieved when the nozzle is moved on the surface. The nozzle also has conventional thread pick up devices 15 arranged centrally in front of and behind the nozzle opening 13 and scraper blades 16 made from elastic material arranged behind the nozzle opening. The scraper blade 16, which is fastened to a holder 17 arranged parallel to the nozzle opening 13 being perpendicular to the direction of movement F of the nozzle, comprises a strip shaped, single piece made from rubber, plastic or some other kind of elastic material. The lower edge 18 of the piece abuts the surface 19 and the free length of the piece extending from the holder 17 towards the surface, that is the length of the piece when not being loaded, is larger than the distance A between the lower edge 10 of the holder and the surface 19. The piece has one or several folds 20 placed close to the holder 17 the folds extending perpendicular to the direction of movement of the nozzle. The existence of these folds means that the "spring constant" for the complete piece as well as for the upper part of the piece is reduced with respect to the lower part of the piece when acting on it in the vertical direction. Thus, the piece has such a shape and such properties that during the turning motion of the nozzle it serves as a soft spring for forces which from the surface are applied on the first edge part towards the holder. It should be mentioned that the section of the piece which has the resilient properties can have many different shapes. Instead of using folds more or less curved shapes could be used as well as portions extending symmetrically at two sides of the piece. It is also possible to vary the thickness of the resilient material in order to achieve the resilient properties desired.

Claims: Vacuum cleaner nozzle comprising a nozzle body (10) having a nozzle opening (13) facing the surface to be cleaned, one or several scraper blades each comprising a single, strip shaped piece (16), made from rubber, plastic or some other elastic material and having a first edge part (18) resting on said surface (19) and a second opposite edge part which is secured in a holder (17) or the like in the nozzle body and whose distance (A) from the surface is mainly constant when the scraper blade is moved forwards or rearwards on a hard surface, the free length of the piece (16) extending towards the surface from the holder under free conditions being larger than said distance (A) so that the first edge part (18) during said movement will trail behind the holder seen in the direction of movement of the nozzle characterized in that the piece (16) has such a shape and such properties that when the direction of movement of the nozzle is reversed it serves as a soft spring for forces which from the surface (19) are applied on the first edge part (18) towards the holder (17) thereby shortening the length of the piece (16) between the first edge part (18) and the holder (17). Nozzle according to claim 1 characterized in that the strip shaped piece (16) extends perpendicular to the direction (F) of movement of the nozzle. Nozzle according to any of the preceding claims characterized in that it is provided with one or several folds (20). Nozzle according to claim 3 characterized in that the fold or folds (20) are placed in close vicinity of the holder (17). Nozzle according to any of the preceding claims characterized in that it is provided with distance means, preferably wheels, in order to maintain a constant distance between the surface (19) and the holder (17).

Inventors: RISTAU HOLMER, TUVIN LARS, RISTAU, HOLMER, TUVIN, LARS
Applicants: ELECTROLUX AB, AKTIEBOLAGET ELECTROLUX
Application year: 1996
Main classification: A47L9
IPC codes: A47L9