| Patents for B43L 21 - Blackboard or slate-cleaning devices (5,409) |
|---|
| 10/27/2004 | CN2651002Y Electric dustproof blackboard |
| 10/27/2004 | CN2651001Y Free-erasing dustproof blackboard |
| 10/21/2004 | US20040205919 Disposable dry marker eraser |
| 10/20/2004 | CN2649354Y Black board dust-removing system arrangement |
| 10/13/2004 | CN2647592Y Electric blackboard eraser with means for absorbing the chalk dust |
| 10/13/2004 | CN2647591Y Dust-absorbing blackboard erazer |
| 10/13/2004 | CN2647590Y Chalk dust-absorbing blackboard eraser |
| 10/13/2004 | CN2647589Y Blackboard eraser chalk dust springing storing box |
| 10/07/2004 | WO2004062818A3 Automatic board eraser cleaning machine |
| 10/06/2004 | CN2645936Y Blackboard eraser stand |
| 09/29/2004 | CN2644177Y Blackboard cleaning and scrubbing device |
| 09/22/2004 | CN2642528Y Dustless noiseless electric eraser |
| 09/22/2004 | CN2642527Y Blackboard eraser having dismountable wiping surface |
| 09/22/2004 | CN2642523Y Novel soft blackboard |
| 09/15/2004 | CN2640768Y Blackboard erazing machine |
| 09/08/2004 | CN2639019Y Electric eraser with device for absorbing chalk dust |
| 09/01/2004 | CN2637205Y 多功能粉笔擦 Multifunction rub chalk |
| 09/01/2004 | CN2637204Y Dustless chalk eraser |
| 09/01/2004 | CN2637203Y 无尘黑板擦 Clean eraser |
| 09/01/2004 | CN2637202Y Chalk eraser cleaner |
| 09/01/2004 | CN2637201Y 环保粉笔擦 Environmental rub chalk |
| 09/01/2004 | CN2637200Y 电动黑板擦 Electric eraser |
| 09/01/2004 | CN2637199Y Dust-proof blackboard eraser |
| 09/01/2004 | CN2637198Y Blackboard eraser with device for absorbing chalk dust |
| 09/01/2004 | CN2637193Y Fully self-service rotary blackboard |
| 09/01/2004 | CN1164436C Method for making clean dust-exhausting black-board eraser |
| 08/25/2004 | CN2635389Y Enviornmental protection black board eraser |
| 08/25/2004 | CN2635388Y 无尘黑板擦 Clean eraser |
| 08/25/2004 | CN2635384Y Electric dustless backboard |
| 08/25/2004 | CN2635383Y Self erasing blackboard |
| 08/18/2004 | CN2633590Y Multifunction blackboard |
| 08/11/2004 | CN2631778Y Blackboard eraser |
| 08/11/2004 | CN2631777Y Electric dustproof blackboard eraser |
| 08/11/2004 | CN1519137A Magnetic electric eraser |
| 08/10/2004 | US6772472 Eraser having selectively openable and closable aperatures |
| 08/04/2004 | CN2630000Y Environmental-protection type dust-free blackboard eraser |
| 08/04/2004 | CN2629999Y Blackboard eraser |
| 08/04/2004 | CN2629998Y 电动黑板擦 Electric eraser |
| 08/04/2004 | CN2629997Y Section-erasible blackboard eraser |
| 07/29/2004 | WO2004062818A2 Automatic board eraser cleaning machine |
| 07/28/2004 | CN2628283Y Dustless chalk eraser |
| 07/28/2004 | CN2628282Y Automatic removing chalk dust blackboard eraser capable of rolling inversely |
| 07/28/2004 | CN1159161C Circulating blackboard without erasing it |
| 07/14/2004 | CN2625162Y Environmental protection blackboard scraper |
| 07/14/2004 | CN2625161Y Electric controlled cycle type dust-free teaching board |
| 07/07/2004 | CN2623473Y Dust collection units of primary and secondary wireless blackboard eraser |
| 07/07/2004 | CN2623472Y Dust-free automatic board erasing device |
| 07/07/2004 | CN2623471Y Dust-absorbing blackboard eraser |
| 07/07/2004 | CN2623470Y Automatic blackboard eraser device |
| 07/07/2004 | CN1509903A Rotary flexible blackboard |
| 06/30/2004 | CN2621942Y Dust removing eraser |
| 06/30/2004 | CN2621938Y Environmental protection auto blackboard |
| 06/23/2004 | CN2621121Y Eraser with device for absorbing chalk dust |
| 06/09/2004 | CN2619799Y Non-dust chalk eraser |
| 06/09/2004 | CN1502481A 电动粉笔擦 Electric rub chalk |
| 06/03/2004 | WO2004045782A2 An electromotive chalk eraser |
| 06/02/2004 | CN2618779Y Blackboard eraser with duster |
| 05/26/2004 | CN2617600Y Dust and water filter on blackboard |
| 05/26/2004 | CN2617599Y Automatic blackboard sponge |
| 05/19/2004 | CN2616404Y Dry-wet two-purpose eraser |
| 05/19/2004 | CN2616403Y Blackboard eraser |
| 05/19/2004 | CN2616402Y Apparatus for filtering floating-dust from erasing chalk characters on blackboard |
| 05/19/2004 | CN2616401Y Ink container packing box and blackboard eraser |
| 05/19/2004 | CN2616400Y Multifunctional teaching aid |
| 05/19/2004 | CN1150095C Apparatus and method for automatically erasing blackboard |
| 05/12/2004 | CN2614935Y Blackboard eraser with means for absorbing the chalk dust |
| 05/12/2004 | CN2614934Y Electric blackboard eraser |
| 05/12/2004 | CN2614933Y 无尘黑板擦 Clean eraser |
| 04/27/2004 | CA2202886C Writing board |
| 04/22/2004 | DE20319916U1 A steel whiteboard cleaner has a rigid foam material handgrip with permanent magnets on the flat face and interchangeable cleaning sheets |
| 04/21/2004 | CN2612544Y 黑板 Blackboard |
| 04/14/2004 | CN2611182Y Electric dust-absorption eraser |
| 04/14/2004 | CN2611181Y Multi-functional black-board eraser |
| 04/14/2004 | CN2611176Y Multi-functional dustless black-board |
| 04/14/2004 | CN2611175Y Rolling-up type black-board |
| 04/07/2004 | CN2609777Y Automatic eraser |
| 04/07/2004 | CN2609776Y Eraser structure |
| 04/07/2004 | CN2609775Y Electric environmental protection energy-saving eraser |
| 04/07/2004 | CN2609771Y Electrostatic dust-suction blackboard |
| 03/31/2004 | CN2608306Y Dust-absorbing blackboard earser |
| 03/31/2004 | CN2608305Y Dust-removing blackboard easer device |
| 03/25/2004 | US20040055622 Cube white board eraser |
| 03/17/2004 | CN2606684Y Blackboard erasing machine |
| 03/03/2004 | CN2605130Y Net type dustfree blackboard |
| 02/26/2004 | US20040037612 Apparatus for erasing and cleaning a marker board |
| 02/25/2004 | CN2604330Y Dust absorbnig chalk eraser |
| 02/04/2004 | CN2601859Y Environmental protection type chalk-dust suction black-board eraser |
| 02/04/2004 | CN2601858Y Novel dust-free blackboard eraser |
| 01/21/2004 | CN2600258Y Blackboard with small power dust cleaner |
| 01/21/2004 | CN2600257Y Rotation blackboard with chalk powder storing box |
| 01/14/2004 | CN2598761Y Dust-collecting blackboard eraser |
| 01/14/2004 | CN2598760Y 防尘黑板擦 Dust eraser |
| 01/07/2004 | CN2597215Y Wall automatic dust-removing blackboard eraser |
| 01/07/2004 | CN2597211Y Fully-automatic lift dust-absorbing blackboard |
| 01/07/2004 | CN2597210Y Rolling-type self-wiping blackboard |
| 01/07/2004 | CN2597208Y Water washing type dust-proof teaching board for audio-visual instruction |
| 12/31/2003 | CN2595590Y New dust suction blackboard eraser |
| 12/31/2003 | CN2595589Y 吸尘黑板擦 Eraser dust |
| 12/31/2003 | CN2595588Y Electric dust remover for blackboard |
| 12/31/2003 | CN2595587Y Blackboard eraser |