Brushing – scrubbing – and general cleaning – Machines – Brushing
Reexamination Certificate
1999-04-02
2002-10-15
Chin, Randall E. (Department: 1744)
Brushing, scrubbing, and general cleaning
Machines
Brushing
C015S048000, C015S052100, C015S079200, C015S083000
Reexamination Certificate
active
06463616
ABSTRACT:
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims the priority of Austrian Patent Application Serial No. A 635/98, filed Apr. 14, 1998, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a drive system for two counter-rotating cylindrical brushes of a floor cleaning machine which includes a motor, a gear mechanism and a force transmitting system for transmitting a torque from the gear mechanism to the cylindrical brushes.
Floor cleaning machines with two counter-rotating cylindrical brushes are known. Such machines typically include a rotating drum that is arranged between the cylindrical brushes and has a rotation axis that is located above the rotation axes of the cylindrical brushes. Water is applied to the floor to be cleaned or to one of the brushes, and the water together with the dirt, picked up by the brushes, is then propelled towards the drum surface. A water film forms on the drum which holds the dirt that is picked up from the floor on the surface of the drum. Also provided are devices for lifting the soiled water film from the drum and transferring the soiled water film to a waste water container.
SUMMARY OF THE INVENTION
In general, it is an object of the invention to provide an improved design of such floor cleaning machines. The object is attained by several design features described hereinafter.
A first important aspect of the invention is the drive system. The drive system includes—as mentioned above—a motor, a gear mechanism and a force transmitting system for transmitting a torque from the gear mechanism to the cylindrical brushes. Conventional gear mechanisms have a single driven shaft. Typically, the two cylindrical brushes are driven by a multistage gear drive disposed on each cylindrical brush, i.e., by several meshing gear wheels having parallel rotation axes. A gear mechanism constructed in this manner disadvantageously requires multiple stages to drive the brushes, which significantly reduces the efficiency of the drive system and also generates objectionable noise.
It is therefore an object of the invention to obviate these drawbacks, and to provide a drive system of the type described above with a high efficiency.
This object is attained in accordance with the invention by providing each cylindrical brush with its own separate driven shaft.
In this way, both cylindrical brushes can be connected directly and independently of each other to the gear mechanism, and a malfunction of one drive connection does not affect the other drive connection. The direct connection of each brush to the gear mechanism produces the required high efficiency.
According to a preferred embodiment of the invention, the force transmitting system may include toothed disks and toothed belts which are secured to the driven shafts and to the shafts of the cylindrical brushes and which connect one of the toothed disks of the driven shaft with a respective toothed disk located on the cylindrical brush. A toothed belt drive of this type is very effective and highly efficient. The toothed belt drive also operates very quietly, so that of the cleaning machine produces very little noise.
According to another embodiment of the invention, a further toothed disk may be secured on a driven shaft and connected via another toothed belt to a toothed disk that is secured on the driven shaft of the drum. The drum is then driven independently from the brushes, so that the drum is still operational in the event that the drives of the brushes malfunction. Furthermore, the toothed belt drive is very effective and operates very quietly.
According to another feature of the drive system of the invention, the gear mechanism may include a pinion secured to the motor drive shaft and two primary gear wheels that engage with the pinion, as well as a secondary gear wheels meshing with the primary gear wheels, wherein the first driven shaft is connected to one of the primary gear wheels and the second driven shaft is connected to the secondary gear wheel. In this manner, the counter-rotation of the cylindrical brushes can be attained employing only a few components. The driven shafts of the gear mechanism are connected to the motor pinion only via one or two stages, thereby further contributing to the high overall efficiency of the drive system.
According to yet another feature of the invention, the pinion, the primary gear wheels and the secondary gear wheel may be implemented as spur gears made of steel. This guarantees a long lifetime of the gear wheels.
According to another advantageous feature of the invention, the pinion, the primary gear wheels and the secondary gear wheel may be helical gears that are known to produce a particularly low noise level .
The toothed disks of the force transmitting system may also be made of steel, aluminum, plastic and the like. Toothed disks made of steel advantageously have a long lifetime which reduces the frequency of repairs of the cleaning machine. Plastic and aluminum gears advantageously produce low noise levels.
According to another embodiment of the invention, the motor is a synchronous motor. Motors of this type can be controlled with relatively simple control circuits. Moreover, synchronous motors are known to support the high brush rotation speed required, for example, for waxing floors. Consequently, the cleaning machine according to the invention is suitable for waxing floors, in particular marble floors.
Advantageously, an electronic device for controlling the rotation speed of the motor can be provided to adapt the cleaning machine to different dirt conditions encountered in practice. The motor can be started smoothly with such control, thereby improving the motor lifetime.
According to another advantageous feature, the floor cleaning machine of the invention includes a stripping device for lifting the soiled water film from the floor, transferring the film to the drum and then transferring the soiled water film to a waste water container. Such floor cleaning machines with a stripping device with at least one rotating brush, preferably a cylindrical brush, and with a drum, on which a water film is disposed and to which the dirt picked up by the brush is transferred, are known in the art. The stripping device lifts this soiled water film from the drum and transfers the film to a waste water container. The stripping device is formed as a strip which contacts the outer surface of the drum along the entire width of the drum.
Conventionally, the strip is biased by a plurality of spaced-apart springs and thereby pressed against the surface of the drum. The thus realized pressing of the strip at only spaced-apart localized points may cause problems, since the water film is then properly lifted from the drum surface only in certain sections, while the water film in other sections forms a dam in front of the strip before being lifted. This significantly impairs the reliable removal of dirt.
It is therefore another object of invention to provide an improved stripping device which obviates these drawbacks and ensures that the water film is reliably lifted across the entire width of the drum.
Thus, according to another aspect of the invention, a rigid strip holder is provided that extends substantially across the entire lengths of the strip, wherein the strip holder is biased towards the surface of the drum by at least one spring. The rigid strip holder distributes the spring bias force evenly across the entire length of the strip and therefore biases the strip against the drum surface with a biasing force that is constant over the entire length of the strip. Uneven biasing forces that can otherwise cause the water film to form a dam, are thereby eliminated.
Advantageously, the strip holder is pivotally supported, with the spring pivoting the portion of the strip holder carrying the strip towards the drum surface. This type of support can be easily implemented.
According to yet another feature of the invention, the strip holder can be secured in fixed rotative engagement on a
Chin Randall E.
Feiereisen Henry M.
Rotowash Reinigungsmaschinen Ges.m.b.H
LandOfFree
Floor cleaning machine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Floor cleaning machine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Floor cleaning machine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2980040