FIELD OF THE INVENTION
The present invention generally relates to power tools and accessories and, more particularly, to a mechanism for cooling the blade of a rotary power tool during an operation on a work piece.
BACKGROUND OF THE INVENTION
Power tools, such as grinders used in working stone, often use circular cutting saws which need to be cooled during a cutting operation. A typical grinder has a fluid inlet from which a cooling fluid (e.g., water) is directed through openings in the spindle of the tool in a direction generally parallel to the axis of rotation of the spindle and saw blade. The saw blade is held on the spindle by a mount having a spindle opening which extends completely through the mount. During a normal flush cutting operation (i.e., an operation in which the blade is generally parallel to the face of the work piece), fluid flows through the spindle and mount down onto the work piece. However, if the tool is turned ninety degrees to perform a cut, water is directed away from the work piece instead of toward it.
SUMMARY OF THE INVENTION
This invention is directed to, among other things, a mount for mounting a blade on a spindle of a power tool for rotation of the blade about an axis to perform an operation on a work piece. The spindle has an axial bore through which a cooling fluid may flow. The mount comprises a body comprising a disk with a central axis generally coincident with the axis of rotation. The disk has an inner face, an outer face, and a peripheral edge. A bore in the body is generally centered on the central axis of the disk. The bore has an open end for receiving the spindle of the power tool and a closed opposite end. At least one fastener opening in the outer face of the disk is spaced in a radial direction from the central axis for receiving a fastener to attach a blade in face-to-face relation with the outer face of the disk. One or more grooves are provided in the outer face of the disk extending from a central region of the disk outwardly to the peripheral edge of the disk. Each groove has an open side adapted to be closed by the blade when the blade is in face-to-face relation with the outer face of the disk. One or more flow passages connect the spindle-receiving bore in the body to respective one or more grooves for flow of cooling fluid along the grooves to the work piece when the blade is in face-to-face relation with the outer face of the disk.
In another aspect, this invention is directed to an adapter for diverting axial fluid flow through the spindle of a power tool to fluid flow in a generally radial direction with respect to an axis of rotation of a blade on the spindle. The adapter comprises a disk having an inner face, an outer face, a peripheral edge, and a central axis. Fastener openings extend through the disk from its outer face to its inner face for receiving fasteners to attach the disk to a blade mount on the spindle of the power tool such that the inner face of the disk is in face-to-face relation with a blade positioned between the blade mount and the disk. One or more grooves in the inner face of the disk extend from a central region of the disk outward to the peripheral edge of the disk. Each groove has an open side adapted to be closed by the blade when the blade is in face-to-face relation with the outer face of the disk whereby cooling fluid flowing axially through bores in the spindle and blade mount is diverted by the disk for flow along the grooves to the work piece.
Other objects and features will be in part apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective of a mount of this invention mounting a blade on the rotary spindle of a power tool;
FIG. 2 is an exploded perspective showing various components of the assembly of FIG. 1;
FIG. 3 is an enlarged top perspective of the mount of FIG. 1;
FIG. 4 is an enlarged bottom perspective of the mount;
FIG. 5 is an enlarged section taken in the plane of line 5-5 of FIG. 1;
FIG. 6 is an enlarged section taken in the plane of line 6-6 of FIG. 1;
FIG. 7 is an exploded perspective showing an adapter of this invention as used with a conventional mount for mounting a blade on the rotary spindle of a power tool;
FIG. 8 is an enlarged top perspective of the adapter of FIG. 7;
FIG. 9 is an enlarged bottom perspective of the adapter of FIG. 7; and
FIG. 10 is an enlarged cross sectional view of an assembly of the spindle, mount, blade, and adapter of FIG. 7.
Corresponding reference characters indicate corresponding parts throughout the drawings.
DETAILED DESCRIPTION
FIGS. 1 and 2 illustrate a power tool, generally designated 10, having a head 12 with a spindle 14 rotatable about an axis of rotation 16, a handle 20 extending from the head, an on/off switch 24, a power cord 26, and a fluid (e.g., water) supply line 30 attached to the handle. A rotary blade 34 is mounted on the spindle 14 by a mount of the present invention generally indicated at 40. The blade 34 shown in this embodiment is a thin, circular, substantially planar blade for performing a grinding or polishing or cutting operation on a work piece (not shown) such as stone or the like, but other types of blades for other types of operations may also be used with the mount of this. When the power tool 10 is turned on, the blade 34 is rotated about the axis 16 to perform an operation on a work piece. Fluid from the supply line 30 is used to cool the blade during such an operation.
As illustrated in FIGS. 5 and 6, the spindle 14 includes a threaded shaft 44 having a central axial bore 48 communicating with the fluid supply line 30. Fluid flows through the bore 48 and exits a number of orifices 50 in a nozzle 52 on the end of the shaft 44. The length and configuration of the spindle 14 can vary. A mount 40 of the present invention can be used with many different spindles found on conventional power tools used for cutting, grinding, polishing, and other operations.
The mount 40 functions to mount the blade 34 on the spindle 14 of the power tool 10 in an orientation in which the plane of the blade is generally perpendicular to the axis of rotation 16. As illustrated, the mount 40 comprises a one-piece body 60 of suitable material, e.g., a metal such as brass. However, the body 60 can be made of separate pieces rigidly affixed to one another.
The body 60 comprises a relatively flat, circular disk 64 having an outer face 66, an inner face 68, and a peripheral edge 70. The outer face 66 has a raised center region forming a boss 72. The boss 72 is sized and shaped to fit a central opening 74 in the blade 34, as will be described later. As used herein, the term “disk” is not intended to limit the perimeter shape of the member to a circular shape. The disk can have a peripheral edge having other shapes (e.g., square) without departing from the scope of this invention.
In the illustrated embodiment (FIGS. 1-6), the body 60 also includes a cylindrical hub 76 extending from the inner face 68 of the disk 64 generally coaxial with the disk. A spindle-receiving bore 80 extends through the hub 76 into the disk. The bore is 80 threaded for threaded engagement with the shaft 44 of the spindle 14. The exterior surface of the hub 76 is formed with parallel flats 84 on opposite sides of the hub to facilitate threading and tightening the hub on the spindle of the power tool 10.
The bore 80 through the hub 76 has an open inner end for receiving the spindle 14 of the power tool 10 and a closed outer end. In the illustrated embodiment (see FIGS. 5 and 6), the bore 80 is a blind bore that stops short of the outer face 66 of the disk 64, i.e., does not penetrate the outer face of the disk. Alternatively, the bore 80 could extend completely through the disk 64, and a plug could be used to close the bore adjacent its outer end.
The blade 34 has a number of clearance holes 90 through it spaced around the center axis of the blade and the central opening 74 of the blade. The disk 66 has a corresponding number of fastener openings 94 for receiving a corresponding number of fasteners 98 to attach the blade to the disk (see FIGS. 2 and 5). The fasteners 98 are preferably threaded fasteners which extend through the blade holes 94 and thread into respective fastener openings 98 in the disk to secure the blade 34 in a position in which the boss 72 is snugly received in the central opening 74 in the blade, and in which one face of the blade (its inner face) is in face-to-face relation with the outer face 66 of the disk 64, e.g., in direct face-to-face contact with the outer face of the disk (see FIGS. 5 and 6). In the illustrated embodiment, eight fastener openings 94 are provided in the disk 64 spaced at generally equal intervals around the disk. The eight openings 94 correspond to two different hole configurations for two different types of blades (i.e., four fastener openings 94 for each type of blade). The number and configuration of the fastener openings can vary.
Referring to FIGS. 4 and 6, a number of grooves 100 are provided in the outer face 66 of the disk 64 extending generally from adjacent the central region 72 of the disk outward to the peripheral edge 70 of the disk. In the illustrated embodiment, the disk 64 has four such grooves 100 spaced at ninety-degree intervals around the central axis 16 of the disk, but the number of grooves can vary from one to two or more spaced at appropriate intervals around the disk. As viewed in a cross section taken transverse to its length (FIGS. 3, 4, and 6), each groove 100 is generally U-shaped, having a bottom wall 104, opposite side walls 108 extending outward from the bottom wall, and an open side 112. The open side 112 is closed by the inner planar face of the blade 34 when the blade is secured to the disk 64. As shown in FIG. 4, the grooves 100 are straight grooves extending in generally radial directions. However, the grooves may have other configurations (e.g., curved).
Referring to FIG. 6, one or more flow passages 120 connect the spindle-receiving bore 80 in the body 60 of the mount 40 to respective one or more grooves 100 for flow of cooling fluid along the grooves to the work piece when the blade 34 is fastened to the disk. In the illustrated embodiment, there are four such flow passages 120, one for each groove 100. The flow passages 120 extend at an angle (e.g., 45 degrees) from the spindle-receiving bore 80 to the grooves 100. This angle may vary.
In use, the spindle 14 of the power tool 10 is threaded into the spindle-receiving bore 80 in the mount 40 such that the orifices 50 in the end of the nozzle 52 are in fluid communication with the bore and the flow passages 120 leading to the grooves 100 (see FIG. 6). The blade 34 is fastened to the disk 64 using the fasteners 98 so that the blade is tight against the outer face 66 of the disk. In this position, the flat inner face of the blade 34 closes and substantially seals the open sides 112 of the grooves 100. As a result, when the power tool 10 is turned on to rotate the spindle 14, and fluid is delivered to the supply line 30, fluid flows through the spindle 14 into the spindle-receiving opening 80 and passes, via the flow passages 120, through the grooves 100 to the periphery of the blade for cooling the blade during an operation on a work piece. The closed end of the spindle-receiving bore 80 prevents the cooling fluid from passing axially through the disk 64, as in prior designs. As a result, the power tool can be used to perform operations in which the tool is rotated ninety degrees to the work piece.
FIGS. 7-10 show a second embodiment in which an adapter of this invention, generally designated 200, is used with a conventional mount 204 for mounting a blade 208 on the spindle 210 of a power tool 214 for rotation about an axis 216. The power tool 214 is identical to the power tool 10 of the previous embodiment. It has a head 220, a handle 224, a power cord 226, an on/off switch 230, and a fluid supply line 234. As described below, the adapter is used to divert the direction of fluid flow to a work piece generally 90 degrees from a direction generally along the axis 216 of rotation of the blade to a generally radial direction with respect to the axis.
The mount 204 is generally of conventional design. It comprises a flat circular member 240, a generally cylindrical hub 244 extending from the member, and threaded axial bore 250 extending completely through the hub and circular member for receiving the threaded shaft of the spindle 210 (see FIG. 10). The blade 208 has a central opening 260 for receiving a boss 264 on the outer face of the circular member 240, and a plurality of fastener holes 262 spaced around the central axis 216 of the central opening 260 for receiving fasteners 270 to attach the blade 208 in face-to-face contact with the outer face of the circular member. The fasteners 270 thread into corresponding threaded fastener holes 274 in the outer face of the member 240.
The adapter 220 comprises a flat disk 280 having an inner face 282, an outer face 284, a peripheral edge 288, and a central axis 290 which is generally co-axial with the axis of rotation 216 when the adapter is in use. Fastener openings 292 extend through the disk 280 from its outer face 284 to its inner face 282 for receiving the fasteners 270 to attach the disk to the blade mount 204 such that the inner face 282 of the disk is in face-to-face relation with the outer surface of the blade 208 positioned (sandwiched) between the blade mount 204 and the disk 280.
Referring to FIG. 8, a number of grooves 300 are provided in the inner face 282 of the disk 280. The grooves 300 extending from a central region 310 of the disk 280 outward to the peripheral edge 288 of the disk. In the illustrated embodiment, the disk 280 has four such grooves 300 spaced at ninety-degree intervals around the central axis 290 of the disk, but the number of grooves can vary from one to two or more spaced at appropriate intervals around the disk. The inner ends of the grooves 300 (i.e., the ends adjacent the central region 310 of the disk) are in fluid communication with one another and, in this embodiment, intersect at the central region 310 of the disk. The central region is free of fluid-flow apertures extending completely through the disk 280, the arrangement being such that fluid delivered to this region is diverted into the grooves 300 for flow to the periphery of the disk.
As viewed in a cross section taken transverse to its length, each groove 300 is generally U-shaped to have a bottom wall 314, opposite side walls 318 extending from the bottom wall, and an open side 320 (FIG. 9). The open sides 320 of the grooves 300 are closed by the outer planar face of the blade 208 when disk 280 is secured in place with its inner face 282 in face-to-face contact with the outer face of the blade. As shown in FIG. 8, the grooves 300 are straight grooves extending in generally radial directions. However, the grooves 300 may have other configurations (e.g., curved).
In use, the spindle 210 of the power tool 214 is threaded into the spindle-receiving bore 80 in the mount 204. The adapter 220 and blade 208 are fastened to the mount 204 using the fasteners 270 so that the blade positioned between the adapter and the mount with one face of the blade in direct face-to-face contact with the mount and the opposite face of the blade in direct face-to-face contact with the inner face 282 of the disk 280. In this position, the flat outer face of the blade 208 closes and substantially seals the open sides 320 of the grooves 300. As a result, when the power tool 214 is turned on to rotate the spindle 210, and fluid is delivered to the supply line 234, fluid flows through the spindle 210 and through the axial opening 250 of the mount 204. From there, fluid is diverted by the closed central region 310 of the disk 280 to flow in generally radial directions through the grooves 300 outward to the peripheral edge 288 of the disk for cooling the blade during an operation on a work piece. As a result, the power tool can be used to perform operations in which the tool is rotated ninety degrees to the work piece.
When introducing elements of the present invention or the preferred embodiments(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
Patent Application
20110250827
