Abstract:
An apparatus for a stand-up grinder caddy includes a handle assembly and an upper sheath. A lower caddy includes a wheel assembly and a lower sheath for insertion into the upper sheath. A bracket supports a grinder with the bracket attached to a support frame with a joint and to sides of the support frame with a floating head mechanism arranged so as not to extend above a top of the frame and thus minimize a height of the lower caddy for fitting under low overhanging obstacles. A head of the grinder contacts the floor surface and can follow contours of the floor surface. When a tilt handle is pressed the head can be tilted. A height adjustment mechanism adjusts a vertical position of the handle assembly for different user heights. The handle assembly can be rotated to a position such that the lower caddy can pass under overhanging obstacles.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present Utility patent application claims priority benefit of the U.S. provisional application for patent Ser. No. 60/880,876 filed on Jan. 16, 2007 under 35 U.S.C. 119(e). The contents of this related provisional application are incorporated herein by reference for all purposes. 

   FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER LISTING APPENDIX 
   Not applicable. 
   COPYRIGHT NOTICE 
   A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or patent disclosure as it appears in the Patent and Trademark Office, patent file or records, but otherwise reserves all copyright rights whatsoever. 
   FIELD OF THE INVENTION 
   The present invention relates generally to grinders. More particularly, the invention relates to the operation of a detachable handheld grinder mounted to a frame supported by wheels. 
   BACKGROUND OF THE INVENTION 
   There are many existing grinders that are used in the construction and floor coating industries. There are large grinders specifically designed to grind large areas. These large grinders enable operators to stand during operation. However, due to the configuration of the abrading discs, there is typically an area of the surface near walls or other obstacles that must remain un-ground by large grinders. Operators mainly use two methods for grinding areas that are unreachable with larger grinders. Operators may use handheld grinders that can grind up to the walls. However, these hand-held grinders are typically operated while on hands and knees, which results in operator fatigue and decreased productivity yet provides a significant amount of control. For example, a handheld grinder can be tilted when needed to grind sloped concrete around a drain or to grind out an occasional low spot found along a wall. Also with handheld grinders, an operator can use their body weight to apply pressure to the abrading disc. 
   A second method for grinding areas that are unreachable with larger grinders is to use a grinder carriage that is operated from behind and can be fitted with a small grinder that can be oriented to grind up against the wall. This method addresses some of the fatigue issue of handheld grinders; however, these grinder carriages typically cannot be adjusted for height. Also, it is not easy for the operator to adjust the angle of the grinder if the operator wishes to grind sloped concrete, for example, without limitation, around a drain or to grind out an occasional low spot found along a wall. Grinder carriages provide some methods for adjusting the angle of the abrading disc and the orientation of the grinding in relation to a wall, however, with these methods the operator must stop grinding to configure the grinder, which decreases productivity. Grinder carriages do not match the versatility one can obtain by using a handheld grinding apparatus due to the fact that the operator stands behind the grinder and has no means to adjust the angle of the grinder without stopping operation. In some instances the operator may need to provide added weight to the grinder to effectively grind areas, and with existing grinder carriages, it is difficult for operators to add weight to the grinding surface. Typically, the operator must add weights to the grinder carriage if possible. Furthermore, when an operator hits uneven concrete with an existing grinder carriage, the grinder is difficult to control unless the operator is standing or kneeling right next to the grinder. Also, currently known grinder caddies have high pivot points for the floating head. A high pivot point makes it difficult for an operator to reach under obstacles such as, but not limited to, cabinets, sinks, shelves, etc. 
   In view of the foregoing, there is a need for improved techniques for providing a grinder that may be used in tight areas such as, but not limited to, next to walls or under obstacles that reduces fatigue of the operator and provides a significant amount of control. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which: 
       FIG. 1  is a perspective view of an exemplary stand-up grinder caddy with an adjustable height tilt mechanism and a low profile floating head, in accordance with an embodiment of the present invention; and 
       FIGS. 2 and 3  illustrate an exemplary adjustable height mechanism from a stand-up grinder caddy with adjustable height, in accordance with an embodiment of the present invention.  FIG. 2  is a perspective view of the adjustable height mechanism, and  FIG. 3  is a close-up perspective view of the adjustable height mechanism with the leg retracted and a leg release clamp disengaged. 
   

   Unless otherwise indicated illustrations in the figures are not necessarily drawn to scale. 
   SUMMARY OF THE INVENTION 
   To achieve the forgoing and other objects and in accordance with the purpose of the invention, a stand-up grinder caddy with adjustable height and low profile floating head is presented. 
   In one embodiment, a stand-up grinder caddy apparatus for a detachable grinder for a floor surface is presented. The apparatus includes an upper caddy including a handle assembly including a front handle and a back handle and an upper sheath positioned vertically downward and proximate the back handle. A lower caddy includes a wheel assembly and a lower sheath positioned vertically upward and proximate the wheel assembly. The lower sheath has a diameter suitable for insertion into the upper sheath. A support frame extends horizontally from the wheel assembly. A bracket supports a front portion of the grinder. The bracket is attached to a distal end of the support frame with a rod end joint and to sides of the support frame with a floating head mechanism such that a grinder head of the grinder contacts the floor surface and can follow contours of the floor surface. Left and right alignment posts are attached to the support bracket for positioning a handle of the grinder between the alignment posts. A tilt lever is attached to the support frame including a first end disposed in the lower sheath and a second end disposed in a opening of the support frame with a handle harness attached to the second end for vertically supporting the handle of the grinder. A height adjustment mechanism is attached to the upper sheath where when the height adjustment mechanism is disengaged a vertical position of the upper sheath relative to the lower sheath can be adjusted for different user heights and when the height adjustment mechanism is engaged the vertical position is maintained. The first handle is positioned in a first position on a vertical line passing through the grinder head such that the user can supply a downward pressure on the front handle to speed a grinding process of the floor surface. In another embodiment the apparatus further includes a tilt activating mechanism including a tilt handle attached to a tilt rod. The tilt handle is positioned proximate the handle assembly with the tilt rod extending through the upper and lower sheaths contacting the tilt lever where when the tilt handle is pressed the handle harness is vertically raised and the grinder head can be tilted. In yet another embodiment the tilt activating mechanism further includes an adjustable height mechanism where when the vertical position is adjusted a length of the tilt activating mechanism can be correspondingly adjusted. In still another embodiment when the height adjustment mechanism is disengaged the upper caddy can be rotated to a second position such that the lower caddy can pass under overhanging obstacles. In a further embodiment the floating head mechanism includes a plurality of floating head levers and springs arranged so as not to extend above a top of the support frame and thus minimize a height of the lower caddy for fitting under low overhanging obstacles. Yet another embodiment further includes a dust shroud configured to surround the grinding head and a vacuum port attached to the dust shroud where debris from the grinding process can be removed from the floor surface by a vacuum process. Other embodiments further include a light attached to the handle assembly for directing a beam of light to the floor surface to assist the user in the grinding process under overall dim lighting conditions and an electrical box attached to the upper caddy including and an on/off switch where the grinder can be plugged into the electrical box and the user can operate the power to the grinder with the switch. 
   In another embodiment, a stand-up grinder caddy apparatus for a detachable grinder for a floor surface is presented. The apparatus includes means for providing a handle assembly for moving the apparatus, means for providing a wheel assembly, means for supporting the grinder, means for allowing the grinder to follow contours of the floor surface and means for adjusting the height of the handle assembly means relative to the supporting means for different user heights. Other embodiments further include means for tilting the grinder, means for adjusting a height of the tilting means and means for rotating the handle assembly means such that the apparatus can pass under overhanging obstacles. Still other embodiments further include means for removing debris from a grinding process of the floor surface, means for lighting the floor surface and means for controlling a power to the grinder. 
   In another embodiment, a stand-up grinder caddy apparatus for a detachable grinder for a floor surface is presented. The apparatus includes an upper caddy including a handle assembly including a front handle and a back handle and an upper sheath positioned vertically downward and proximate the back handle. A lower caddy includes a wheel assembly and a lower sheath positioned vertically upward and proximate the wheel assembly. The lower sheath has a diameter suitable for insertion into the upper sheath. A support frame extends horizontally from the wheel assembly. A bracket supports a front portion of the grinder with the bracket attached to a distal end of the support frame with a rod end joint and to sides of the support frame with a floating head mechanism including a plurality of floating head levers and springs arranged so as not to extend above a top of the support frame and thus minimize a height of the lower caddy for fitting under low overhanging obstacles such that a grinder head of the grinder contacts the floor surface and can follow contours of the floor surface. Left and right alignment posts are attached to the support bracket for positioning a handle of the grinder between the alignment posts. A tilt lever attached to the support frame including a first end disposed in the lower sheath and a second end disposed in a opening of the support frame and a handle harness attached to the second end for vertically supporting the handle of the grinder. A tilt activating mechanism has a tilt handle attached to a tilt rod. The tilt handle is positioned proximate the handle assembly with the tilt rod extending through the upper and lower sheaths contacting the tilt lever where when the tilt handle is pressed the handle harness is vertically raised and the grinder head can be tilted. A height adjustment mechanism is attached to the upper sheath where when the height adjustment mechanism is disengaged a vertical position of the upper sheath relative to the lower sheath can be adjusted for different user heights. When the height adjustment mechanism is engaged the vertical position is maintained and the first handle is positioned in a first position on a vertical line passing through the grinder head such that the user can supply a downward pressure on the front handle to speed a grinding process of the floor surface. When the height adjustment mechanism is disengaged the upper caddy can be rotated to a second position such that the lower caddy can pass under overhanging obstacles. In another embodiment the tilt activating mechanism further includes an adjustable height mechanism where when the vertical position is adjusted a length of the tilt activating mechanism can be correspondingly adjusted. Yet another embodiment further includes a dust shroud configured to surround the grinding head and a vacuum port attached to the dust shroud where debris from the grinding process can be removed from the floor surface by a vacuum process. Still other embodiment further include a light attached to the handle assembly for directing a beam of light to the floor surface to assist the user in the grinding process under overall dim lighting conditions and an electrical box attached to the upper caddy including and an on/off switch where the grinder can be plugged into the electrical box and the user can operate the power to the grinder with the switch. 
   Other features, advantages, and object of the present invention will become more apparent and be more readily understood from the following detailed description, which should be read in conjunction with the accompanying drawings. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention is best understood by reference to the detailed figures and description set forth herein. 
   Embodiments of the invention are discussed below with reference to the Figures. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments. For example, it should be appreciated that those skilled in the art will, in light of the teachings of the present invention, recognize a multiplicity of alternate and suitable approaches, depending upon the needs of the particular application, to implement the functionality of any given detail described herein, beyond the particular implementation choices in the following embodiments described and shown. That is, there are numerous modifications and variations of the invention that are too numerous to be listed but that all fit within the scope of the invention. Also, singular words should be read as plural and vice versa and masculine as feminine and vice versa, where appropriate, and alternative embodiments do not necessarily imply that the two are mutually exclusive. 
   The present invention will now be described in detail with reference to embodiments thereof as illustrated in the accompanying drawings. 
   Embodiments of the present invention provide grinder caddies that can be mounted with hand-held grinders that may be used to grind concrete or other suitable surfaces while operators are in standing positions and have significant control over the maneuverability of the grinders. The preferred embodiment of the present invention is a grinding apparatus that has an adjustable height that can match the height of the operator. The preferred embodiment also has a low profile floating head that enables a user to effectively grind under areas that are typically unreachable by currently known standing grinders, for example, without limitation, near walls, under sinks, under cabinets or shelves, etc. 
   In the past, grinder caddies have not had the ability to be adjusted for height and have had a high pivot point for the floating head. Also, due to the previous design, areas that grinders could reach were limited. Embodiments of the present invention have several advantages over current grinders. For example, without limitation, the ability to adjust the height of the grinder caddy to match height of operator may increase productivity due to an increase in ease of use. Also, lowering the pivot point of the floating head enables the user to be able to reach under cabinets and other obstructions that cannot be reached by current stand up grinders. In some embodiments an upper handle of the grinder caddy rotates to increase the ability of the grinder to reach under obstacles, such as, but not limited to, shelves, cabinets, sinks, etc. Furthermore, some embodiments comprise a flat surface above the grinder upon which an operator may place a foot to apply pressure to the grinder. This takes the strain off of the hands when applying pressure and results in greater productivity. 
     FIG. 1  is a perspective view of an exemplary stand-up grinder caddy with an adjustable height tilt mechanism and a low profile floating head, in accordance with an embodiment of the present invention. In the present embodiment an upper caddy handle  1  comprises a front handle  2 , an electrical box  3 , an on/off switch  4 , a back handle  5 , and a light  53 . A power cord  6  runs from electrical box  3  to a standard power outlet (not shown). Light  53  may be turned on to improve visibility when grinding in poorly lit areas. Alternate embodiments may not comprise a light. In the present embodiment, a height adjustment bolt  7  is screwed into a height adjustment clamp housing  8 . A tongue (not shown) is cut out of an upper caddy sheath  9  where height adjustment bolt  7  applies pressure to hold an upper caddy  46  at a specific height. In alternate embodiments, various other means may be used to hold the upper caddy at the desired height such as, but not limited to, a clamp, a threaded leg, a bolt with cut holes, etc. Upper caddy sheath  9  fits snuggly around a lower caddy sheath  11 . A leg release lever  40  controls an adjustable height mechanism within upper caddy sheath  9  and lower caddy sheath  11 , shown by way of example in  FIGS. 2 and 3 . Also a grinder tilt handle  50  enables the operator to adjust the tilt of a grinder  26  mounted to the grinder caddy. 
   A lower caddy  10  comprises a lower caddy u-support  12  and left and right castor wheels,  13  and  14  respectively. Castor wheels  13  and  14  enable the grinder caddy to be easily maneuvered by an operator. A vacuum pipe support  15  is welded to lower caddy  10 . Attached to vacuum pipe support  15  is a vacuum pipe  16 . Within lower caddy u-support  12  is a tilt lever support  18 . Tilt lever support  18  holds a tilt lever  17  via a tilt lever pivot bolt  19 . A grinder handle harness  21  is attached to tilt lever  17  via a bolt (not shown). Attached to the bottom of lower caddy u-support  12  are a left grinder alignment post  22   a  and a right grinder alignment post (not shown). A rod end joint  23  is bolted to lower caddy u-support  12 . A grinder bracket  25  is attached to rod end joint  23  via a grinder bracket bolt  24 . Grinder bracket  25  holds grinder  26  via a left grinder bolt  27   a  and a right grinder bolt (not shown) so that a grinder head  52  rests on the surface to be ground. 
   A grinder power cord  28  is plugged into electrical box  3  during operation of grinder  26 . A dust shroud  29  is held in place via a shroud seal clamp  30 . A vacuum hose  47  runs from dust shroud  29  to vacuum pipe  16 . Vacuum hose  47  and vacuum pipe  16  direct the dust captured in dust shroud  29  in a direction away from the operator, and some embodiments may also include a bag to collect this dust at the opening of vacuum pipe  16 . Alternate embodiments may be implemented without a dust shroud, vacuum hose or vacuum pipe. In the present embodiment, a left gas spring  31   a  and a right gas spring (not shown) are attached to lower caddy u-support  12  via a left bolt  48   a  and a right bolt. A left floating head lever  32   a  and a right floating head lever  32   b  are attached to left gas spring  31   a  and right gas spring by a left bolt  49   a  and a right bolt (not shown). Left floating head lever  32   a  and right floating head lever  32   b  are attached to lower caddy u-support  12  via a left floating head bolt  33   a  and a right floating head bolt (not shown). Left floating head lever  32   a  and right floating head lever  32   b  are attached to grinder bracket  25  via a left swivel joint rod end linkage  34   a  and a right swivel joint rod end linkage (not shown). 
   In typical use of the present embodiment, an operator stands alongside grinder  26  and can adjust the height of upper caddy handle  1  by loosening height adjustment bolt  7  and sliding upper caddy sheath  9  to a comfortable height, then tightening height adjustment bolt  7  to lock upper caddy  46  into place. If an operator needs to grind under obstacles, such as, but not limited to, cabinets or sinks, the operator can loosen height adjustment bolt  7  and rotate the entire upper caddy  46  over 90 degrees for maximum clearance. Also, grinder  26  is mounted in such a way to lower caddy u-support  12  that the area under which the grinder can reach is maximized. In order to speed grinding time, an operator can apply weight to the grinder. This is easy to accomplish with the present embodiment by pressing down on front handle  2 . If additional weight is needed, an operator may place a foot directly above grinder  26  on lower caddy u-support  12 . Alternate embodiments may comprise a plate attached to lower caddy u-support  12  to provide a larger area for the operator to apply pressure to grinder  26  with his foot. In the present embodiment, grinder head  52  is able to glide over uneven surfaces and grind the top off this uneven surface due to the floating head mechanism. The floating head mechanism works due to rod end joint  23  and gas springs  31   a  and  31   b , which enable grinder head  52  to move up and down freely. Alternately, one may use levers and pulleys to mount the grinder to the u-support  12 . The low mounted configuration of gas springs  31   a  and  31   b  as they are attached to grinder bracket  25  and lower caddy u-support  12  in the present embodiment and the low pivot point of this system enable grinder head  52  to follow the contours of uneven concrete and fit under obstacles more effectively than previously known designs. 
     FIGS. 2 and 3  illustrate an exemplary adjustable height mechanism  35  from a stand-up grinder caddy with adjustable height, in accordance with an embodiment of the present invention.  FIG. 2  is a perspective view of adjustable height mechanism  35 , and  FIG. 3  is a close-up perspective view of adjustable height mechanism  35  with a leg  37  retracted and a leg release clamp  44  disengaged. In the present embodiment, a leg sheath  36  comprises a leg release rod  39 , a leg release lever  40 , and a spacing ring  41 , which holds leg release rod  39 . Leg release lever  40  is located above a grinder tilt handle  50  on leg release rod  39 . Leg release rod  39  is fed through a leg release pivot  42 , which is attached to leg sheath  36  via a leg release pivot bolt  43 . Leg release clamp  44  is welded to leg release pivot  42 . In alternate embodiments leg release pivot  42  and leg release clamp  44  may be attached with various different means such as, but not limited to, a bolt, etc. In the present embodiment, leg release clamp  44  fits into a leg sheath cutout  51  when leg release point  40  is not pressed holding leg  37  in place. Leg release clamp  44  is held against leg sheath cutout  51  via a spring  45 . In alternate embodiments leg release clamp  44  may hold leg  37  in place using alternate means such as, but not limited to, notches in leg  37  into which leg release clamp  44  fits, leg  37  may be threaded and adjusted by rotating the leg  37  inside leg sheath  36 , etc. [It should be further mentioned that in the preferred embodiment leg  37  is threaded and the leg release clamp  44  has a threaded nut that prevents the leg from slipping. In the present embodiment, leg  37  is partly sheathed in leg sheath  36 . A leg base  38  is attached to the bottom of leg  37 . Adjustable height mechanism  35  is encased in upper caddy sheath  9  and lower caddy sheath  11 , shown by way of example in  FIG. 1 . Leg base  38  rests on top of tilt lever  17  inside of lower sheath  11 , shown by way of example in  FIG. 1 . In the present embodiment, grinder tilt handle  50  and leg release point  40  extend above back handle  5 , shown by way of example in  FIG. 1 . 
   The length of adjustable height mechanism  35  can be adjusted by pressing on leg release point  40  to loosen leg release clamp  44  to compensate for the height of upper caddy  46  when raised or to increase the angle that grinder head  52  can be tilted. To lengthen or shorten adjustable height mechanism  35 , the operator pushes down on leg release point  40 , which raises leg release clamp  44  from leg sheath cutout  51  allowing leg  37  to extend or retract. When leg  37  is extended or retracted to an adequate length for grinder tilt handle  50  to raise above back handle  5  pressure applied to leg release point  40  is released, which causes leg release clamp  44  to lock leg  37  into place. The operator is then able to change the angle of grinder  26  while operating grinder  26  by pressing down on grinder tilt handle  50 , which causes leg base  38  to apply pressure to tilt lever  17 . 
   In order to effectively grind along walls or on sloped concrete, for example, without limitation, around drains, the operator may control the angle of grinder  26 . In typical use of the present invention, grinder  26  is mounted to lower caddy u-support  12  so that grinder head  52  is flat when grinder tilt handle is in a neutral position. To change the angle of grinder head  52 , an operator presses down on grinder tilt handle  50  and leg base  38  of adjustable height mechanism  35  pushes down on tilt lever  17 . When tilt lever  17  is depressed, grinder handle harness  21  rises, raising the back of grinder  26  and tilting the front end of grinder  26  including grinder head  52  in a downward direction. Grinder head  52  pivots around left grinder bolt  27   a  and right grinder bolt attaching grinder head  52  to grinder bracket  25 . Left grinder alignment post  22   a  and right grinder alignment post  22   b  keep grinder  26  lined up with lower caddy u-support  12  by restricting the movement of grinder  26  in the left and right directions. In the present embodiment, the operator maintains pressure on grinder tilt handle  50  to maintain the desired angle for grinder  26 . However, alternate embodiments may comprise means for holding the grinder at a desired angle such as, but not limited to a strap to hold down the grinder tilt handle, a clamp, preset angle settings corresponding to catch points on the leg sheath, etc. 
   In alternate embodiments leg  37  may not include a leg base, and instead leg  37  may be directly attached to tilt lever  17  for example, without limitation, with a pivot bolt. In these embodiments the operator may tilt grinder head  52  downward or upward by either pushing or pulling on grinder tilt handle  50 . Pulling on grinder tilt handle  50  pulls tilt lever  17  up thus lowering handle harness  21  and the back of grinder  26 , and this tilts grinder head  52  upward. In other alternate embodiments the angle of the grinder may be controlled with various different means. For example, without limitation, a foot pedal may be attached to the tilt lever enabling the operator to control the angle of the grinder with his foot, or a hand lever may be attached to the tilt lever. Some of these alternate embodiments may not comprise a height adjusting mechanism for the grinder tilt control if the control means are implemented on the lower caddy rather than the upper caddy since the lower caddy does not move when the height of the upper caddy is adjusted. 
   Those skilled in the art, in light of the present teachings, will recognize that alternate embodiments of the present invention may comprise different materials, sizes, and interconnections for all components. For example, without limitation, various means other than height adjustment bolt  7  may be used to hold the upper caddy at the desired height such as, but not limited to, a clamp, a threaded leg, a bolt with cut holes, etc. Also, the grinder handle may be mounted to the caddy by various means other than grinder handle harness  21  such as, but not limited to, a hook, an adjustable strap, etc., and these means may be attached to tilt handle  17  with various means, such as, but not limited to, bolts, welding, buckles, clamps, etc. Furthermore, the grinder tilt handle may be shaped differently or the upper caddy handle may be shaped differently or may comprise various different grips. For example, without limitation, in an alternate embodiment, the upper caddy handle may comprise a U-shaped handle with grips similar to a bicycle handle. Furthermore, the electrical box may not be included in some alternate embodiments. In embodiments not comprising an electrical box, the power cord of the grinder mounted in the caddy is plugged directly into a standard wall socket. 
   Having fully described at least one embodiment of the present invention, other equivalent or alternative methods of providing a standup grinder caddy with adjustable height according to the present invention will be apparent to those skilled in the art. The invention has been described above by way of illustration, and the specific embodiments disclosed are not intended to limit the invention to the particular forms disclosed. For example, the particular implementation of the grinder mounting means may vary depending upon the particular type of grinder used. The grinder mounting means described in the foregoing were directed to implementations using small hand held grinders; however, similar techniques are to use larger grinders or a built in grinder head. Implementations of the present invention using various different grinders are contemplated as within the scope of the present invention. The invention is thus to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the following claims.