Cleaning and liquid contact with solids – Processes – Combined
Reexamination Certificate
1999-09-23
2001-10-30
Coe, Philip R. (Department: 1746)
Cleaning and liquid contact with solids
Processes
Combined
C015S001700
Reexamination Certificate
active
06309468
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to a working method for cleaning a swimming pool using a cleaning device that moves backwards and forwards across the floor of a swimming pool and has a drive mechanism that can be switched to forward or backward travel and is actively connected to drive wheels or drive tracks, a respective motor for each of a left-hand-side and a right-hand side part of the drive mechanism, a control apparatus for controlling the drive mechanism, and contacts arranged at the front and rear to generate control signals in the event that the cleaning device approaches a swimming pool wall or an obstacle. The invention further relates to cleaning device for cleaning a swimming pool for carrying out the method according to the invention.
Cleaning devices moving automatically backwards and forwards on the bottom of the swimming pool have been known for a considerable time. In most cases, however, they have the disadvantage that pools of irregular shapes cannot be cleaned automatically and reliably. Particularly in the low-cost range, there is a need for appropriate simple devices.
DE-3 110 203 describes a method and a device for cleaning a swimming pool which, in a known manner, moves backwards and forwards on the bottom of a water-filled swimming pool and, in doing so, cleans it by suction. The device has two motors, so that the two sides of the drive mechanism can run forwards or backwards or remain stationary independently of each other. The device additionally possesses a control apparatus which is influenced by four sensors arranged at the corners of the device and controls the travel of the device on the bottom of the swimming pool between opposite swimming pool walls in a zigzag path. The device travels alternately forwards and backwards. It does not turn at the swimming pool walls, but performs small pivoting movements there on each occasion. These pivoting movements firstly enable the cleaning device to be aligned relative to the swimming pool wall and secondly allow a new direction of movement to be set subsequently. Since the cleaning device has one motor for each of the two sides of the drive mechanism, one of the two motors is shut down on each occasion in order to achieve the alignment movements and changes of direction, the other motor continuing to run during the alignment operation or during a delay period. As a result, the cleaning device rotates about the shut-down drive part.
One of the disadvantages of this cleaning device resides in the fact that changes of direction can only be performed relatively imprecisely. The achievable accuracy of the angle of change of direction depends on factors which are difficult to control, such as, for example, the different dynamic performance of the two sides of the drive (inter alia, during starting conditions) and the pronounced dependence on the delay period. The consequence of this is that, especially in the case of relatively long travels, the reliable overlap of the cleaning tracks and hence the complete cleaning of the pool bottom may not be guaranteed under certain circumstances. The principle disadvantage, however, resides in the fact that this cleaning device is not suitable for pools of different sizes without careful adjustment of the delay period and is only suitable for rectangular or square pool shapes.
The object of the present invention is therefore to provide a simple method for cleaning and a reasonably priced cleaning device which can be used both in pools of different sizes and in pools of different shapes and guarantee reliable cleaning of the pool bottom.
SUMMARY OF THE INVENTION
The above object generally is achieved, according to a first aspect of the invention, by a method for cleaning a swimming pool using a cleaning device that moves backwards and forwards in the swimming pool and has a drive mechanism that can be switched to forward or backward travel and is actively connected to drive wheels or drive tracks, a respective motor for each of a left-hand-side and a right-hand-side part of the drive mechanism, a control apparatus for controlling the drive mechanism, and contacts arranged at the front and rear to generate control signals in the event that the cleaning device approaches a swimming pool wall or an obstacle; and wherein the control apparatus possesses, for each part of the drive mechanism, a speed regulating apparatus, and means for the differential control of the speed of the two motors; with the method including measuring the distances (d
1
,d
2
) covered in forward or backward movement by both parts of the drive mechanism of the cleaning device; and, in the control apparatus, calculating and differentially controlling angles (R
1
,R
2
) of change of direction for the travelling cleaning device based on the measured distances (d
1
,d
2
) covered and an offset width (v) of the respective travel tracks.
The above object is generally achieved according to a second aspect of the invention by a cleaning device for carrying out the above method; having a drive mechanism which can be switched to forward or backward travel and is actively connected to drive wheels or drive tracks; a respective motor for each of a left-hand-side and a right-hand-side part of the drive mechanism; a control apparatus for controlling the drive mechanism; and a contact means arranged at the front and rear to generate control signals in the event that the cleaning device approaches a swimming pool wall or an obstacle; and wherein: the control apparatus possesses, a speed regulating apparatus for each respective part of the drive mechanism, and means for the differential control of the speed of the two motors; the cleaning device has a means on both parts of the drive mechanism for measuring the distances covered in forward or backward travel; and the control apparatus possesses means for calculating and differentially controlling changes of direction of the travelling cleaning device based on the measured distances covered and an offset width of the respective travel tracks.
The object is achieved, in essence, in that for a left-hand and right hand part of the drive mechanism, means for measuring the distance covered on the pool bottom and means for differentially controlling the motors of the two parts of the drive mechanism at different speeds are used. The initial result of this is that the control apparatus of the cleaning device can automatically and independently calculate the angle of change of direction required for the next cleaning pass and perform the necessary control functions. In particular, however, the effect achieved is that the respective angles of change of direction can be set very precisely and without resorting to high-cost control technology such as, for example, travel-direction sensors.
According to a preferred embodiment of the invention, the control apparatus of the cleaning device is so constructed that a choice can be made between two or more different working programmes. Thus, for example, a first working program can be provided for the cleaning of swimming pools of any desired shape, the cleaning device in this working program undertaking no alignment operations at all at the swimming pool walls. A further working program can, for example, be provided for the cleaning of swimming pools having at least one suitable, linear, reference swimming pool wall, the cleaning device in this working program performing an alignment relative to the reference swimming pool wall on each occasion.
An embodiment of the invention with two working programs of this type is explained in more detail in the following text with reference to the drawings.
REFERENCES:
patent: 2988762 (1961-06-01), Babcock
patent: 4786334 (1988-11-01), Nystrom
patent: 5208521 (1993-05-01), Aoyama
patent: 5256207 (1993-10-01), Sommer
patent: 5435031 (1995-07-01), Minami et al.
patent: 31 10 203 (1982-09-01), None
patent: 0 099 489 (1984-02-01), None
patent: 0 257 006 (1988-02-01), None
patent: 0 483 677 (1992-05-01), None
patent: 2 584 442 (1987-01-01), None
3S Systemtechnik AG
Coe Philip R.
Kunitz Norman N.
Venable
LandOfFree
Working method and cleaning device for cleaning a swimming pool does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Working method and cleaning device for cleaning a swimming pool, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Working method and cleaning device for cleaning a swimming pool will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2602877