1. Field of the Invention
The present invention relates to drivers for abrasive disks and more particularly to a driver that provides the proper speed for abrasive clean and strip discs.
2. Description of the Related Art
There is presently no designated driver for abrasive clean and strip discs, such as the clean and strip discs currently marketed by 3M Company (St. Paul, Minn.), Norton (Worcester, Massachusetts) and other manufacturers. The 3M discs are sold under the trademark Scotch-Brite™. The Norton discs are sold under the trademark Bear-Tex®. Typically, these abrasive discs have recommended maximum speeds of 8,000 rpm. However, users of these discs generally apply them to angle grinders that have speeds of about 18,000 rpm or on drill motors having speeds about 2,400-3,400 rpm. Thus, they are generally run either too fast or too slow. Running these too fast is dangerous. Running too slow prevents effective use.
It is therefore desired to have a driver that proper rpm for these types of abrasive clean and strip discs for safety and efficiency reasons.
In a broad aspect, the present invention is a driver for abrasive disks, that includes a housing assembly, a motor assembly, a driven pulley assembly, and, a belt. The motor assembly is supported by the housing assembly and connectable to a power source. The motor assembly has a motor output shaft with a motor output shaft axis. The motor assembly includes a motor drive pulley operatively connected to the motor output shaft. A driven pulley assembly is supported by the housing assembly. The driven pulley assembly has a rotatably mounted driven pulley with a driven pulley axis. The driven pulley assembly is for attaching an abrasive disk. A belt is operatively connected to the driven pulley and to the motor drive pulley. The motor output shaft axis and the driven pulley shaft axis are parallel thereby obviating the requirement of any gears. This provides a driver that is quiet, i.e., only about 78-81 decibels, depending on the muffler. Also, the life expectancy is much higher than a conventional bevel-gear drive.
The same elements or parts throughout the figures of the drawings are designated by the same reference characters, while equivalent elements bear a prime designation.
Referring now to the drawings and the characters of reference marked thereon,
A housing assembly, designated generally as 12, includes an elongated handle section 14, a motor housing section 16, and a support plate section 18. The elongated handle section 14 includes a switching element, e.g. trigger 20, and a connector 22 for connection to a power source (not shown). The power source may be pneumatic, electric or hydraulic.
A motor assembly 24 is supported by the housing assembly 12 and is connectable to the power source. The motor of the motor assembly 24 is enclosed by the motor housing section 16. The motor assembly 24 has a motor output shaft 26 with a motor output shaft axis 28. The motor assembly 24 includes a motor drive pulley 28 operatively connected to the motor output shaft 26.
A driven pulley assembly, designated generally as 30 is supported by the housing assembly 12. The driven pulley assembly 30 includes a rotatably mounted driven pulley 32 with a driven pulley axis 34. The driven pulley axis 34 and motor output shaft axis 28 are parallel. Thus, the motor assembly is transversely mounted relative to the axis of the elongated handle section. The driven pulley assembly 30 is for attaching an abrasive disk 36. A belt 38 is operatively connected to the driven pulley and to the motor drive pulley 28. The driven pulley assembly 30 includes a driven pulley support element 40 that is securely connected, via fasteners 42, to the support plate section 18 of the housing assembly 12. The driven pulley support element 40 has an opening defined by a threaded inner surface 44 thereof. A driven pulley shaft 46 is secured within the threaded inner surface. A bearing assembly 48 is supported by the driven pulley shaft 46. The bearing assembly 48 includes appropriate ball bearings 50 and a retaining ring 52. A second retaining ring 54 secures the driven pulley 32. A disk attachment member 56 is securely attached to the driven pulley 32. The disc attachment member 56 supports the abrasive disk 36.
A drive cover 58 is securely attached, via fasteners 60 to the driven pulley support element 40. A motor housing cover 62 provides access to the motor. A guard 64 is also utilized.
Other embodiments and configurations may be devised without departing from the spirit of the invention and the scope of the appended claims.