Patent Application
20080057842
The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying drawing figures, in which:
At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the invention. While the present invention is described with respect to what is presently considered to be the preferred aspects, it is to be understood that the invention as claimed is not limited to the disclosed aspects.
Furthermore, it is understood that this invention is not limited to the particular methodology, materials and modifications described and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present invention, which is limited only by the appended claims.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. Although any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the preferred methods, devices, and materials are now described.
The following is a broad overview of assembly 20, further details are provided below. Assembly 20 includes body, or casing 30, rotatable element, or spindle, 36, and locking assembly 21. Casing 30 is arranged for connection to a drive means, for example, screw 18, rotatable about a axis of rotation 52. Element 36 is arranged for connection to a pad assembly, for example pad assembly 45, and is rotatable about axis of rotation 54, disposed substantially parallel to axis of rotation 52. Locking assembly 21 is arranged to lock rotatable element 36 to body 30 to prevent rotation of element 36, relative to body 30, about axis of rotation 54.
Locking assembly 21 includes element, or pin, 26 displaceable to rotationally lock rotatable element 36. Assembly 21 also includes element 22, engageable with element 26 and displaceable to control the displacement of element 26, and elastically deformable element 25 arranged to urge element 26 in direction 23. In some aspects, element 25 is a spring. However it should be understood that any elastically deformable element known in the art can be used. As further described below, element 22 is engageable with element 26 to urge element 26 in direction 29, to lock element 36 with body 30. Rotatable element 36 includes at least one receiving feature engageable with element 26. The receiving feature can be an opening, for example, opening 37, or an indentation.
Casing 30 of assembly 20 includes threaded port 28, pin hole 32, and sliding bolt hole 24. Pin hole 32 is operatively arranged to accept pin 26 and retention spring 25. Retention spring 25 retains pin 26 in a disengaged position, with respect to element 36, until sliding bolt 22 is engaged.
Pin 26 includes rib 27, upon which retention spring 25 rests. Sliding bolt hole 24 is operatively arranged to accept sliding bolt 22. In some aspects, sliding bolt 22 protrudes through both sides of sliding bolt hole 24 so that an operator can access both ends of slide sliding bolt 22 to move the bolt from an engaged to a disengaged position. In some aspects, sliding bolt 22 protrudes through one side substantially more so that the other side dependent upon whether sliding bolt 22 is in the engaged or disengaged position. Sliding bolt 22 protrudes through to a first side substantially more than a second side in the engaged position, and protrudes through the second side substantially more than the first side in the disengaged position. The engaged and disengaged positions are further described below. The preceding configuration enables easy engagement or disengagement of the sliding bolt 22 when the operator is wearing work gloves.
Sliding bolt 22 rotates with head assembly 20 when rotary tool 10 is engaged. This rotation inhibits a user from accidentally engaging sliding bolt 22 while the tool is being used and causing unnecessary wear on the components.
Casing 30 acts as a shell and structural support for ball bearing assembly 34, spindle 36, and counterbalance 40. Ball bearing assembly 34 provides for rotation, about axis 54, of spindle 36, base support 44, pad base 45 and pad 48 independent of casing 30. It should be appreciated that any ball bearing means known in the art can be used for ball bearing assembly 34. It also should be appreciated that any rotation support means known in the art can be used for rotation about axis 54, for example a bushing arrangement (not shown).
In some aspects, spindle 36 includes a plurality of holes or indentations. Some of the holes, for example, holes 37, are engagement holes and some of the holes, for example, holes 39 are bearing retention holes. It should be appreciated that any number of holes could be used. In some aspects, three holes for engagement holes 37 and three holes for retention holes 39 are used for ease of balancing and manufacturing. Balancing is very important in rotary tools in order to minimize undesirable vibration. Engagement holes 37 are about the same size as the diameter of pin 26 and are operatively arranged to accept pin 26. Retention holes 39 are of a size larger that the heads of retention screws 38. Retention screws 38 hold ball bearing assembly 34 to casing 30. It should be appreciated that any means of attachment known in the art can be used. In some aspects, retention screws 38 in a set of three are used for balancing and ease of manufacturing. Pin hole 32 and holes 37 are at a same radial distance from axis 54 to facilitate the alignment of pin 26 and the holes as further described below.
In some aspects, counterbalance 40 is bolted into casing 30 by means of bolts 42 to provide a balanced rotation of both orbital and rotational motion and thereby reduce vibrations.
As noted above, elastically deformable element, or spring, 25 applies constant force to pin 26 to urge the pin in direction 23. This force tends to keep pin 26 engaged with which ever of slots 62 or 64 in which the pin is disposed. In the unlocked mode, pin 22 is positioned so that pin 26 is disposed in slot 62. Length 31 of pin 26 is less than or equal to axial length 33 between pin 22 and element 36, so that in the unlocked mode, pin 26 does not extend far enough in direction 29 to engage element 36 and element 36 is able to rotate without substantive interference from pin 26.
To switch to the locking mode, pin 22 is laterally displaced so that pin 26 shifts to slot 64, displacing pin in direction 29 and into opening 37, as shown in
The locking mechanism herein described locks the rotation of the pad assembly, which comprises base support 44, pad base 45, and pad 48 about second axis 54. Thus, the pad assembly will only rotate about first axis 52 with casing 30.
In some aspects, components of head assembly 20 are machined from metal. In some aspects, other material including, but not limited to composites, plastics, and combinations thereof are used to make the components. In some aspects both metal and one or more of the other materials are used to form the components. It should also appreciated that any form of metal processing could be used, including casting, pressing, welding, machining, and combinations thereof. In some aspects, machining is used to increase precision.
Base support 44 and pad base 45 are affixed to each other by glue, but it should be appreciated that any means of attachment known in the art can be used. Base support 44 is made of a non-pliable material that provides structural support for pad base 45 and also a means for pad bolt 46 to be tightened to spindle 36. Pad base 45 is made of a pliable material that will provide for a dampened interface between a work surface and the user. Preferably, base support 44 is made from plastic and pad base 45 is a high density foam or similar rubber, but it should be appreciated that any similar materials could be used for either base support 44 or pad base 45. Base support 44 is attached to spindle 36 by means of pad bolt 46. Pad bolt 46 is recessed within pad base 45 and is most clearly shown in
Referring back to
It should be appreciated that any type of pad 48 could be used. Pad 48 could be a piece of sand paper of any grit size. Alternatively, pad 48 could be a polishing pad, buffing pad, or any other pad known in the art.
Thus, it is seen that the objects of the present invention are efficiently obtained, although modifications and changes to the invention should be readily apparent to those having ordinary skill in the art, which modifications are intended to be within the spirit and scope of the invention as claimed. It also is understood that the foregoing description is illustrative of the present invention and should not be considered as limiting. Therefore, other embodiments of the present invention are possible without departing from the spirit and scope of the present invention.
