Patents for B43L 21 - Blackboard or slate-cleaning devices (5,409)
07/2002
07/31/2002CN2502914Y Movable eraser
07/24/2002CN2501699Y Electric dust-absorption blackboard eraser
07/24/2002CN2501698Y Dust-proof dust-removing electric eraser capable of moving at all directions
07/24/2002CN2501696Y Fully automatic dust-removing blackboard eraser
07/18/2002US20020092106 Board wiper cleaning device
07/17/2002CN2500490Y Dust absorpting blackboard
07/17/2002CN1359339A An apparatus and a method for automatically erasing a blackboard
07/10/2002CN2499243Y New dust collection blackboard brush for teaching
07/10/2002CN2499242Y Envirnment protection black board eraser
07/03/2002CN2497988Y Clean water jetting blackboard eraser
07/03/2002CN2497987Y Automatic duster for blackboard
07/03/2002CN2497985Y Circularly liftable blackboard
06/2002
06/26/2002CN2496677Y Multifunctional dust-absorbing eraser
06/26/2002CN2496676Y Electric dust-absorbing blackboard eraser
06/26/2002CN2496675Y Dust-absorbing regular eraser
06/26/2002CN2496674Y Electrostatic blackboard eraser
06/05/2002CN1351935A Return type blackboard
05/2002
05/22/2002CN2492402Y Dust-sucking black board eraser
05/15/2002CN2491253Y Dustless dry-wet combined eraser
05/15/2002CN2491252Y Electrostatic eraser
05/15/2002CN2491251Y Environmental protection eraser
05/15/2002CN2491250Y Multifunctional eraser
05/08/2002CN2489984Y High-efficient chalk dust removal eraser
05/01/2002CN2488700Y Fully automatic dust absorption type blackboard
04/2002
04/17/2002CN2486351Y Electric dust collecting chalk brush
04/17/2002CN2486350Y Static blackboard eraser
04/17/2002CN2486349Y Environment protection dust-proof automatic blackboard eraser
04/16/2002US6370720 Apparatus and a method for automatically erasing a blackboard
04/10/2002EP1195267A2 White board eraser
04/10/2002CN2485150Y Blackboard
04/09/2002US6367115 White board eraser
04/03/2002CN2484195Y Blowing-absorbing type dust-absorbing blackboard eraser
04/03/2002CN2484194Y Blackboard eraser for environmental protection
04/03/2002CN2484193Y Dust-absorbing blackboard eraser
04/03/2002CN2484192Y Dust-absorbing blackboard eraser
03/2002
03/27/2002CN2483206Y Electric chalk-dust absorbing blackboard wiper
03/27/2002CN2483205Y Dust absorbing blackboard wiper
03/27/2002CN2483204Y Novel black-board wiper
03/20/2002CN2482503Y Blackboard with means for automatic cleaning and absorbing the chalk dust
03/13/2002CN2481532Y Dustless blackboard eraser
02/2002
02/27/2002EP1181156A1 An apparatus and a method for automatically erasing a blackboard
02/27/2002CN2478796Y Crawler blackboard without chalk dust
02/27/2002CN2478795Y Crawler eraser
02/27/2002CN2478791Y Automatic dust-removing blackboard (whiteboard)
02/20/2002CN2477406Y Novel dust sucking eraser
02/20/2002CN2477405Y Ash collecting slot of blackboard
02/20/2002CN2477404Y Eraser powder collector
02/20/2002CN2477403Y Electric eraser
02/06/2002CN2475575Y Dustless blackboard eraser
02/06/2002CN2475574Y Electric dust-collecting blackboard eraser
01/2002
01/30/2002CN2474350Y Dust absorbing blackboard eraser
01/30/2002CN2474349Y Convenient blackboard eraser
01/30/2002CN2474347Y Multifunction blackboard eraser
01/30/2002CN2474344Y Multifunction fully automatic environmental protection blackboard
01/23/2002CN2472975Y Dust suction blackboard eraser
01/23/2002CN2472974Y Clean blackboard eraser
01/23/2002CN2472973Y Automatic erasing device for blackboard
01/23/2002CN2472972Y Blackboard eraser
01/23/2002CN2472971Y Dustless chalk brush
01/23/2002CN2472970Y Full automatic blackboard eraser for teaching
01/16/2002CN2471563Y Dust collecting blackboard eraser
01/16/2002CN2471562Y Dust collecting blackboard eraser
01/16/2002CN2471561Y Dust-eliminating eraser
01/16/2002CN2471560Y Automatic dust-collecting eraser
01/16/2002CN2471559Y Blackboard eraser
01/16/2002CN2471552Y Automatic blackboard
01/09/2002CN2470139Y Blackboard eraser
01/09/2002CN2470138Y Writing-board eraser
01/09/2002CN2470137Y Hand-protection blackboard brush
01/09/2002CN2470136Y Dust-free blackboard eraser
01/02/2002CN2468764Y Self chalk dust suction black-board eraser
01/02/2002CN2468763Y Environmental protection type chalk-dust suction black-board eraser
01/02/2002CN2468762Y Self chalk dust absorbing type black board wiper
01/02/2002CN2468752Y Rotary and self-cleaning and non-chalk dust type black board
01/02/2002CN2468751Y Automatic water cleaning and anti reflection type black board
12/2001
12/19/2001CN2465955Y Dust-suction blackboard eraser
12/19/2001CN2465954Y Dust-collecting blackboard eraser
12/19/2001CN2465953Y Dust-collecting blackboard eraser
12/19/2001CN2465952Y Electric chalk dust-less blackboard
12/19/2001CN1327400A Surface treating device
12/18/2001US6330732 Dust collect device for an eraser
12/12/2001CN2464554Y 盒式黑板擦 Cassette eraser
12/12/2001CN2464553Y Slide blackboard
12/05/2001CN2463185Y Dust-collecting eraser
12/05/2001CN2463182Y Circular belt type blackboard
12/05/2001CN2463181Y New blackboard
11/2001
11/28/2001CN2461784Y Chalk powder eraser/sucker
11/28/2001CN2461783Y Novel teacher's pointer eraser
11/28/2001CN2461778Y Electric dustless blackboard
11/21/2001CN2460329Y Eraser with chalk dust absorbing device
11/21/2001CN2460328Y Chalk-dust absorbing type eraser
11/21/2001CN2460327Y Eraser with chalk dust absorbing device
11/21/2001CN2460326Y Eraser
11/21/2001CN2460325Y Eraser
11/21/2001CN2460324Y Dust-proof eraser
11/21/2001CN2460318Y blackboard with dust remover
11/14/2001CN2459185Y Improved blackboard erasing machine
11/14/2001CN2459181Y Fully automatic blackboard
11/07/2001CN2458172Y Blackboard wiper
10/2001
10/31/2001EP1148997A1 Creativity center apparatus and method of use
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