Patent Publication Number: US-4734741-A

Title: Particulate material cleaning apparatus

Description:
TECHNICAL FIELD 
     This invention relates to apparatus for cleaning toner off a moving surface, and more particularly to such apparatus in which particulate cleaning material is brushed across the moving surface. 
     BACKGROUND ART 
     Electrophotographic copiers, printers and the like, using a dry toning and transfer process generally require a cleaning apparatus to remove residual toner from a moving surface after the transfer step. U.S. Pat. Nos. 3,580,673; 4,006,987; 4,110,034; 4,279,499; and 4,515,467 describe examples of cleaning apparatus in which particulate material which is triboelectrically attractive to toner is brushed across the moving surface to clean it. Toner attracted to the particulate material is removed from the particulate material at a location remote from the moving surface and the particulate material recirculated past the moving surface again to pick up more toner. 
     In time, the toner creates a scum on the particulate material, it loses its cleaning ability, and must be replaced. U.S. Pat. No. 4,279,499 shows a magnetic brush cleaning device having a sump for particulate magnetic cleaning material and a skive which can be used to remove the cleaning material to permit the addition of new material. U.S. Pat. No. 4,515,467 shows the metering of cleaning material from a hopper as required by the apparatus. 
     In all such prior apparatus the cleaning material replacement operation is done by a serviceman because of the likelihood of contact with toner, because the cleaning material must be handled in bulk and because of the complexity of the replacement operation. 
     DISCLOSURE OF THE INVENTION 
     It is the object of the invention to provide cleaning apparatus generally of the type using a particulate cleaning material which apparatus facilitates replacement of the cleaning material by a person less skilled than required by the prior art. 
     This and other objects are accomplished by a particulate cleaning material replacement device for a cleaning apparatus of the type described which device includes means for receiving a container containing particulate cleaning material which container has an opening. The container receiving means is rotatable between a first position in which the container opening is generally up and a second position in which said opening is in metering relation with the cleaning apparatus. Means for rotating the container receiving means from its first position to its second position is actuable in response to operation of the apparatus. 
     According to a preferred embodiment, the replacement device is part of a cleaning apparatus which includes a magnetic brush for moving cleaning material through an endless path, which path includes cleaning relation with a toner bearing moving surface. The brush in moving through this path cooperates with a restricted passageway between the container opening and the brush to meter the contents of the container onto the brush. 
     According to another preferred embodiment, the container receiving means is also movable from its second position to its first position, for example, by hand. A skive is movable into stripping relation with the brush in response to this rotation. When the container receiving means is in its first position, an empty container can be removed and a full one inserted and the apparatus turned on or cycled. The container receiving means is then rotatable to its second position. In response to this rotation, the skive first strips particulate material off the brush and then moves to a nonstripping position. 
     According to another preferred embodiment of the invention, a detent prevents removal or insertion of a container except when the container receiving means is in its first position. 
     According to another preferred embodiment of the invention, the apparatus includes a movable detoning means which includes means for driving the rotational movement of the container receiving means from its first position to its second position. 
     This apparatus permits replacement of cleaning material by a relatively unskilled operator. The removal of the old carrier is automatically accomplished in the process of inserting the container having new material. The new material is metered onto the brush as the brush moves through its normal cycle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1 and 2 are side schematic views of a cleaning apparatus constructed according to the invention illustrating &#34;run&#34; and &#34;service&#34; conditions, respectively. 
    
    
     BEST MODE OF CARRYING OUT THE INVENTION 
     According to FIGS. 1 and 2, a magnetic brush cleaning apparatus 1 includes a magnetic brush 2 which is driven by means not shown to transport magnetic particulate cleaning material through an endless path which includes cleaning relation with a moving surface 3. The magnetic brush may be in the form of a belt or, as shown in the Figs., a roller which rotates around stationary magnets, as is well known in the cleaning and toning art. It may also comprise a stationary or rotating shell around rotating magnets, as is well known in the toning art. 
     The particulate cleaning material brushes the moving surface, preferably in a direction opposite to the direction of movement of the surface, picking up residual toner by triboelectric attraction. The residual toner is transported past a detoning means, for example a detoning roller 4, which is electrically biased to attract toner from the brush and which may be driven by a drive means common with that for the brush 2. Toner is cleaned off detoning roller 4 by a cleaning blade 5 and falls into a removal zone or sump where it is removed by an auger 6. As the brush 2 continues to rotate, the particular material, now starved of toner, is returned to the moving surface 3 to continue the cleaning process. 
     Because of scumming and other aspects of use, the cleaning material must be periodically replaced. A particulate cleaning material replacement device 10 forms part of the cleaning apparatus to accomplish this function in a simple and convenient manner. More specifically, a container receiving means 11 is located generally above the brush 2. A cylindrically shaped container 20 is receivable in container receiving means 11. Container receiving means 11 is rotatable through 360 degrees and specifically between a first position, as shown in FIG. 2, and a second position, as shown in FIG. 1. Container 20 has an opening 21 running longitudinally the length of the container and a tab 22. A detent 12 associated with container receiving means 11 prevents insertion or removal of a container except when the receiving means 11 is in its first position as shown in FIG. 2. When the container receiving means 11 is in its second position, longitudinal opening 21 mates with a restricted passageway 19 between the opening 21 and the brush 2. 
     A knob 13, a cam 14 and a driven gear 15, having teeth around approximately 180 degrees of its periphery, are all rotatable with container receiving means 11. A lever 16 follows cam 14 and controls a stripping skive 17. A drive gear 18 is rotatable with detoning roller 4 and drives driven gear 15. 
     In operation, the cleaning apparatus 1 is shown in the &#34;run&#34; position in FIG. 1 with the opening 21 in a generally downward direction and the stripping skive out of engagement with the brush 2. The operator notices poor cleaning or is so signaled by logic of a copier, printer or the like in which the cleaning apparatus is installed. The operator rotates knob 13 clockwise by hand until it reaches the &#34;service&#34; position, as shown in FIG. 2 and as indicated by the knob, thus rotating the container receiving means 11 from its second position to its first position. This rotation of knob 13 also rotates cam 14 and gear 15. Rotation of cam 14 moves stripping skive 17 into stripping engagement with brush 2 through lever 16. Rotation of gear 15 brings the toothed portion into driven engagement with drive gear 18. 
     With the container receiving means 11 in its first position, tab 22 is not prevented by detent 12 from movement parallel to the axis of the container 20. An empty container can now be removed and a full one inserted. 
     After insertion of a container containing fresh cleaning material, the apparatus is turned on or cycled causing the brush 2 and detoning roller 4 to rotate. Rotation of detoning roller 4 causes drive gear 18 to rotate rotating driven gear 15 until the container receiving means 11 reaches its second position and the knob reaches its &#34;run&#34; position, as shown in FIG. 1. This rotation rotates cam 14 to eventually remove stripping skive 17 from the moving brush 2 but only after the used particulate material has been stripped and fallen onto auger 6 for removal. This rotation stops when driven gear 15 has no teeth in engagement with drive gear 18, as shown in FIG. 1. As is well known int he art, separate augers may be provided for toner and cleaning material to permit separate disposal, for example, to reuse the toner. 
     When the container receiving means reaches its second position, particulate material is free to move through opening 21 and passageway 19 under force of gravity and onto moving bare brush 2. The movement of brush 2 and the restriction of passageway 19 meter the particulate material onto the brush. 
     In the &#34;run&#34; position, the container 20 cannot be removed because of detent 12 and tab 22. A new container can only be inserted in an operation which also cleans off the old particulate material, thereby assuring that the brush will never be overloaded and damaged or rendered less efficient because of too much cleaning material. 
     Opening 21 in container 20 can be closed for storage by a tape that is removable by the operator either before insertion into the container receiving means 11 or, with the aid of an elongated tab end, removed after insertion. Alternatively, the container can have a permanent mechanical closure that is automatically slid into an opening position by rotation of the container receiving means 11 or by sliding of the container into the container receiving means 11 in the loading operation. 
     This invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.