Patent Application
20240130583
This application claims the priority, under 35 U.S.C. ยง 119, of German Patent Application DE 10 2022 211 259.8, filed Oct. 24, 2022; the prior application is herewith incorporated by reference in its entirety.
The invention relates to an automatic floor cleaner with a suction facility. The invention relates, in particular, to the mounting of the suction nozzle relative to a chassis of the floor cleaner.
A floor vacuum cleaner is designed to travel over a floor surface and to clean it at the same time. To this end, the floor vacuum cleaner comprises a suction facility which produces an airflow through a suction nozzle that is attached to a chassis of the floor vacuum cleaner. The suction nozzle is configured to be positioned at a predetermined spacing from the floor surface so as not to impede a horizontal entry of large particles of dirt or foreign bodies. However, the spacing should not be too great, in order to be able to use the airflow efficiently for picking up dirt.
If the suction nozzle is rigidly attached to the chassis it can run against an obstacle and impede the movement of the floor vacuum cleaner. If the suction nozzle is arranged so as to be vertically movable, the spacing from the floor surface, for example when traveling over an edge or threshold, can be temporarily too small or too great. Various proposals have been made regarding the movable mounting of a suction nozzle relative to a chassis.
German published patent application DE 10 2010 000 577 A1 relates to a floor vacuum cleaner with a suction nozzle which is pivotably mounted at a rear end relative to the direction of travel. A guide consisting of a sliding guide and a sliding block is provided at a front end in order to permit a vertical movement. The front end on the chassis is pushed by means of a coil spring in the direction of the floor surface. The pick-up of large particles of material in the region of the suction nozzle can be impeded thereby.
It is an object underlying the present invention to provide an improved technique for flexibly attaching a suction nozzle to a floor vacuum cleaner.
With the above and other objects in view there is provided, in accordance with the invention, a floor vacuum cleaner for cleaning a floor surface, the floor vacuum cleaner comprising:
In other words, the objects of the invention are achieved by a floor vacuum cleaner for cleaning a floor surface. The device comprises a chassis with a chassis frame for traveling over the floor surface; and a suction nozzle for the intake of an airflow in the region of the floor surface, wherein the suction nozzle is mounted relative to the chassis in the direction of travel to the front left and right in each case by means of an arrangement consisting of a journal and a guide such that a tilting of the suction nozzle about the journals, a rotation of the suction nozzle about a longitudinal axis and a vertical movement of the suction nozzle are made possible, but a movement of the suction nozzle in the longitudinal direction of the chassis is prevented.
Due to this mounting, the suction nozzle can be held in an improved manner in an advantageous position relative to the substrate. When traveling over an uneven portion, the suction nozzle can still be held such that dirt is effectively picked up from the floor surface. When traveling over a threshold or step, a transition between various floor coverings, a cable, a joint or a different obstacle, the suction nozzle can be guided along the substrate in an improved manner. The suction nozzle can be movable in three predetermined degrees of freedom, wherein a first degree of freedom relates to a tilting of the suction nozzle about a transverse axis of the floor vacuum cleaner, a second degree of freedom relates to a pivoting about a longitudinal axis and a third degree of freedom relates to a displacement along a height axis.
Optionally, the suction nozzle can also be displaced along a transverse axis of the chassis. A resilient element can counteract a displacement from a predetermined position. Restoring forces of the resilient element can be the same or different for a displacement to the left and to the right. To this end, an arrangement with two different resilient elements can be used. The displacement can be limited on one side or two sides to a predetermined path.
Large particles of dirt can enter the region of the suction nozzle and can be suctioned up or aspirated in an improved manner from the floor surface by the combination of the described degrees of freedom. It is possible to avoid the situation where the floor vacuum cleaner becomes stuck on an edge or digs into a soft or deep-pile substrate.
In a preferred embodiment, a journal is provided on the suction nozzle and a guide is provided on the chassis. As a result, a vertical guidance of the journal can be improved. The journals extend along a common axis and can be configured in the manner of trunnions on either side of the suction nozzle. The receiver can be formed by two bearing surfaces which are parallel to one another and which in each case extend perpendicularly to the longitudinal axis of the chassis. A bearing surface can be as narrow as desired; in one embodiment, for example, a vertical cylinder can form the bearing surface. A reverse arrangement in which a journal is provided on the chassis and a receiver is provided on the suction nozzle can also be used.
Further preferably, the suction nozzle is mounted so as to be vertically movable to the rear left and right. A separate guide in this region is not required. The mobility of the suction nozzle can thus be defined as extensive.
In a simple embodiment, a vertical position of the suction nozzle at the rear end is limited by a weight force of the suction nozzle or a component connected thereto. In a preferred embodiment, it is possible to provide a resilient element which is designed to push a rear end of the suction nozzle into a predetermined vertical position relative to the chassis. In each case a resilient element can be provided at a rear left end and a rear right end. A resilient element can act both upwardly and downwardly, wherein the effective spring constants can be the same or different. At the front end a resilient element can be dispensed with; the vertical position preferably being able to be set here due to the weight force of the suction nozzle or in the extension of the rear end.
The resilient element can be formed by a resilient tubular connecting piece through which the airflow flows from the suction nozzle in the direction of the suction facility. The tubular connecting piece is further preferably located on the suction nozzle to the rear in the direction of travel and runs approximately horizontally. The resilience of the tubular connecting piece can be used for positioning the suction nozzle and can assist with the elimination of a separate resilient element. The tubular connecting piece can be designed such that in each case it provides predetermined resilient forces relative to a rotation about a longitudinal axis (second degree of freedom) and a vertical deflection of the suction nozzle (third degree of freedom). These forces can be determined to a certain extent independently of one another by the shape and choice of material of the suction nozzle.
In yet a further preferred embodiment, a deflection of a rear end of the suction nozzle upwardly and/or downwardly from the predetermined position is limited to a predetermined path. A deflection path upwardly can be greater than a deflection path downwardly. For example, the suction nozzle can be deflected upwardly relative to the chassis by approx. 4.5 mm and deflected downwardly by approx. 2.3 mm before a stop limits the movement.
A deflection of the front end of the suction nozzle upwardly can be limited to a further predetermined value. This deflection path can be shorter than a deflection path of the rear end upwardly or downwardly. In one embodiment, the front end can be deflected upwardly by approximately 1-2 mm. A deflection downwardly can not be provided or can be zero.
In another preferred embodiment, a brush roller with an axis of rotation running transversely to the direction of travel is attached in the suction nozzle. The brush roller can be rotated by means of a drive motor about the axis of rotation and it is designed to release or loosen dirt from the floor surface or to guide the dirt in the region of the suction nozzle. A contact of the brush roller with the substrate can be improved by the proposed floating bearing of the suction nozzle, such that the floor surface can be cleaned in an improved manner by means of the brush roller.
A sealing lip can be provided in the region of a rear end of the suction nozzle. The sealing lip preferably extends in the transverse direction and is designed as far as possible to bear against the floor surface and to seal the suction nozzle relative to the floor surface. To this end, the sealing lip is preferably manufactured from a resilient material, so that if required the sealing lip can be resiliently deformed on an obstacle or an uneven portion on the floor surface. A sealing action of the sealing lip relative to the floor surface can be further improved by the described mobility of the suction nozzle relative to the chassis.
A sliding element can be provided for supporting a rear end of the suction nozzle relative to the floor surface. The sliding element can have a surface made of plastics or textile material (thread lifter). If a sealing lip is provided, the sliding element still remains downstream of the sealing lip relative to the direction of travel.
The chassis frame may include a drive wheel and a control device in order to control a movement of the floor vacuum cleaner over the floor surface. The floor vacuum cleaner is preferably provided for the autonomous treatment of a floor surface. The floor surface is further preferably contained within a household and, for example, can relate to one or more rooms.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a floor cleaner with a movably mounted suction nozzle, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now to the figures of the drawing in detail and first, in particular, to
A suction nozzle 120 is provided for treating the floor surface 115, in the present case a brush roller 125 with a horizontal axis of rotation being arranged therein. The suction nozzle 120 is connected via a tubular connecting piece 130 to a suction facility 135 which is preferably arranged downstream of the suction nozzle 105 relative to a direction of travel 140. The suction facility 135 is not directly visible in
The suction nozzle 120 is movably mounted relative to the chassis 105, which is explained in more detail with reference to
A transverse axis 205, a longitudinal axis 210 and a height axis 215 which preferably form a right-handed coordinate system are defined relative to the chassis 105. The suction nozzle 120 can be tilted about the transverse axis 205 which corresponds to a first degree of freedom 225. The suction nozzle 120 can be pivoted about the longitudinal axis 210 which corresponds to a second degree of freedom 230. The suction nozzle 120 can be displaced along the height axis 215 which corresponds to a third degree of freedom 235. Movements of the suction nozzle in the degrees of freedom 225 to 235 can be coupled together in a predetermined manner.
In the embodiment shown, a movement along the transverse axis 205 is made possible by lateral spacings between the suction nozzle 120 and the bearing points on a predetermined path. A resilient element can cause a return into a predetermined position when the suction nozzle 120 is horizontally deflected. The resilient element can be assigned to this movement. In a further embodiment, this movement is prevented, for example, by the afore-mentioned spacings being virtually zero. The suction nozzle 120 is preferably immovable along the longitudinal axis 210. A rotation about the height axis 215 is preferably also prevented. Overall, in this manner the suction nozzle 120 is movable in 4 or 3 degrees of freedom and immovable in the remaining 2 or 3 degrees of freedom.
One respective journal 240 is attached to the suction nozzle 120 to the front left and right with reference to the direction of travel 140. The journals 240 extend along a common axis of rotation. In the schematic view shown, the journals 240 form part of a continuous axis, in a further embodiment the axis can also be interrupted. That is, the journals 240 may be in the form of trunnions at the left and right of the forward edge of the suction nozzle 120. Each journal 240 is received on the chassis 105 in a receiver 245 which prevents a movement of the journal 240 in the direction of the longitudinal axis 210, whereby a rotation of the suction nozzle 120 about the height axis 215 is also prevented. The journal 240 and the receiver 245 with a vertical slot form mounting arrangements for the forward end of the suction nozzle 120. A movement of the suction nozzle 120 along the height axis 215 is possible to a predetermined extent. The receiver 245 is formed with a vertical slot in the bearing position shown, wherein a journal 240 extends through the slot. The boundaries of the slot determine a maximum deflection of the journal 240 or the suction nozzle 120 upwardly and downwardly. A tilting of the suction nozzle 120 about the longitudinal axis 210 is also made possible by the independent mounting of the two journals 240.
Relative to the direction of travel 140, one respective resilient element 250 is provided to the rear left and right in order to bias the suction nozzle 120 in this region into a predetermined position. Optionally a resilient element 250 is dual-acting, or two resilient elements 250 which act in an antiparallel manner are provided, so that a deflection of the suction nozzle 120 from the predetermined position both upwardly and downwardly is counteracted by a corresponding restoring force. At the same time, the spring hardness can be the same or different in the two directions. The resilient element 250 can be pretensioned so that a deflection of the suction nozzle 120 from the predetermined position requires a predetermined minimum force.
Resilient elements 250 can also be provided on the journals 240 or a vertical position of the suction nozzle 120 can be primarily determined in this region by a weight force on the suction nozzle 120.
Resilient properties of the tubular connecting piece 130 can be influenced by its shape, its wall thickness or its material. A resilient force which is brought about by the tubular connecting piece 130, when it is subjected to shear when the suction nozzle 120 is pivoted about the transverse axis 205, can be determined irrespective of a resilient force which it exerts when the suction nozzle 120 is rotated about the longitudinal axis 210. For example, a stiffness of the tubular connecting piece 130 counter to a rotation about the longitudinal axis 210 can be lower when a cross section of the tubular connecting piece 130 is designed to be oval or flat, and higher when its cross section is designed to be round.
A sealing lip 305 which preferably extends parallel to the transverse axis 205 is attached to the suction nozzle 120 downstream of the brush roller 125. A sliding element 310, which is designed to be positioned on the floor surface 115 or to slide thereover, is also preferably attached to the suction nozzle 120 downstream of the sealing lip 305.
The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2022 211 259.8 | Oct 2022 | DE | national |
