|
| US3930548 | 3. Febr. 1975 | 6. Jan. 1976 | | Motorized scaffold attachment |
| US4053025 | 14. Juli 1976 | 11. Okt. 1977 | | Scaffold including reversible and adjustable driving and steering unit |
| US4475611 | 30. Sept. 1982 | 9. Okt. 1984 | Up-Right, Inc. | Scaffold propulsion unit |
| US4662476 | 16. Jan. 1986 | 5. Mai 1987 | | Portable scaffold and retrofit kit therefor |
| US5062242 | 10. Juli 1989 | 5. Nov. 1991 | | High density storage facility |
| US5140787 | 18. Jan. 1991 | 25. Aug. 1992 | | High density storage facility |
| US6076621 | 8. Mai 1998 | 20. Juni 2000 | Spencer Research and Development, Inc. | Mobile work platform |
| US6533067 | 4. Dez. 2000 | 18. März 2003 | | Scaffold moving device |
| US6688426 | 2. März 2002 | 10. Febr. 2004 | | Wheel extension and lift device for ladders |
| US6786299 | 14. März 2003 | 7. Sept. 2004 | | Swivel-power scaffold mobilizing device |
| US6793236 | 25. Okt. 2002 | 21. Sept. 2004 | | Motorized game cart |
| US6880672 | 18. Apr. 2003 | 19. Apr. 2005 | | Self propelled scaffolding |
| US7004284 | 22. März 2002 | 28. Febr. 2006 | | Scaffold moving device |
