US3540169A

US3540169A - Emery ribbon feed and rewinder for sander

Info

Publication number: US3540169A
Application number: US467295A
Authority: US
Inventors: George R Mahoney
Original assignee: GEORGE R MAHONEY
Current assignee: GEORGE R MAHONEY
Priority date: 1965-06-28
Filing date: 1965-06-28
Publication date: 1970-11-17
Anticipated expiration: 1987-11-17

Description

Nov.- 17,1970 (5. R. MAHONEY EMERY RIBBON FEED AND REWINDER FOR SANISER Filed June 28, 1965 2 Sheets.. heet l I N VE NTOR: 620265 A. M4,

BY Mad W h ls Ar 2,5;

United States Patent 3,540,169 EMERY RIBBON FEED AND REWINDER 1 9R SANDER George R. Mahoney, 5749 Arapaho Drive, San Jose, Calif. 95123 Filed time 28, 1965, Ser. No. 467,295 Int. Cl. 324d 13/06 11.5. C1. 51-335 11 Claims ABSTRACT OF THE DISCLOSURE A rotary sander in which a plurality of emery strips extend radially from the slit peripheral wall of a drum housing and backed by brush bristles on such periphery. A mount for pairs of such emery strips looped about pins circumferentially arranged on a disc within the drum housing and extending into bores in a cover for driving relation therewith and relative thereto at the option of the user.

This invention relates to improvements in a rotary abrasive device of the type having a drum for sanding irregular as well as flat surfaces of articles of metal, wood or the like.

Drum type sanders as is generally known consist of a hollow drum provided with radially extending brushes adjacent which sanding ribbons extend from a mounting within the drum. The general arrangement is such that the sanding ribbons are replaceable and mountable for extension and retraction relative to the drum.

The present invention is directed to a novel arrangement of emery ribbons, a mount therefor cooperating with the cover of the drum for releasing and/ or rewinding emery ribbons, and means for interlocking the cover relative to the drum.

It is an object of this invention to provide a simple yet effective and economical way of supplying and preparing the emery strips for mounting in a sanding drum.

It is another object to provide a novel and simple mounting for the emery strips and for relating the latter with the cover for the drum in such a manner as to facilitate rewinding of the strips within the drum or feeding of the strips outwardly from the drum.

It is a further object to provide the cover and drum with interlocking means segmentally spaced to assure locking of the same and ribbon strips in desired positions of extension relative to the drum.

These and other objects and advantages of the present invention will become apparent from a reading of the following description and claims in the light of the two sheets of drawing in which:

FIG. 1 is a plan view of a rotary sander with cover removed to illustrate a portion of the present invention embodied therein.

FIG. 2 is a section through the entire rotary sander of FIG. 1 and taken substantially along line 22 thereof.

FIG. 3 is an exploded perspective view of the parts of the present invention illustrating their interrelationship with each other.

Referring to FIG. 2 the sanding drum 10 has a central shaft 11 press fit and keyed thereto for turning the same. The drum 10 is cup shaped having a solid side wall 12 formed integrally with a peripheral wall 13 which is cylindrical and of a desired depth. The drum 10 is die cast directly onto the shaft 11 so as to become a part thereof and one end of the shaft 11 extends beyond the side wall 12 to fit into the chuck of a power tool (not shown) for rotation thereby. The shaft 11 extends through the drum 10 and has its opposite end 14 threaded to receive a nut N which is knurled. A cover C for the drum 10 is also die cast and has a center bore B sized to fit the shaft 11.

The peripheral wall 13 of the drum 10 has a plurality of segmental lands 15 divided by a plurality of circumferentially space slits or openings 16 each of sufiicient clearance to allow a fiat ribbon strip of emery cloth 17 to pass through. The slits 16 run the full width of the interior of the drum 10 and extend from the inner face of the side wall 12 thereof and open up onto the opposite open side of the drum. In the present disclosure six lands 15 and six slits 16 are shown. Each land 15 has a brush mounting groove 18 formed therein to receive the mounting block 19 of a brush 20, the bristles of which extend radially outward from the drum adjacent the trailing side of an adjacent slit 16.

The brushes 20 serve as a resilient backing for each strand of emery cloth 17 the back face 21 of which engages the brush to present the abrasive surface 22 of the emery cloth 17 to the article to be sanded. The brushes 20 and strips of emery cloth 17 are substantially the width of the interior 23 of the drum and inner ends of the strips 17 are mounted therein in a manner now to be explained.

A mount for the emery cloth strips 17 designated 25 comprises a flat disc 26 provided with a central bore 27 which fits over the shaft 11 which extends transversely and axially through the drum 10. The inner face of the side wall 12 of the drum has a recess 28 formed therein to receive the disc 26, the disc and recess 28 having substantially the same thickness and depth so that the inner surface of the disc lies flush with the inner surface of the side wall of the drum.

The disc 26 is free to turn about the shaft 11 and is firmly centered relative thereto and relative to the base of the recess 28. A plurality of pins 29 are mounted on the inner face of the disc 26 and extend upwardly there from across the interior 23 of the drum and slightly beyond the open side thereof. There is one such pin 29 for each pair of slits 16 through which the emery cloth strips 17 extend. There being six strips 17 there are three pins 29 equally spaced in tripod fashion upon the disc 26.

In accordance with the present invention the strips 17 of emery cloth are joined in pairs with their abrasive surfaces 22 facing in one and the same direction. In other words, one strip 17 is laid with its abrasive surface 22 down and another strip 17 is laid over it with the abrasive surface 22 thereof against the back surface 22 of the lowermost strip 17. The two strips 17 thus disposed are then secured together by a wire staple 30 adjacent one end 31 of the two strips. This is done with any well known form of stapling machine or device. The two strips 17 thus joined are mounted on one of the pins 29 and the balance of each strip is strung out through separate and adjacent slits 16 in the peripheral wall 13 of the drum.

Now when the mount 25 for the strips 17 is turned within and relative to the drum 10 all of the strips 17 will be wound about the equally spaced pins 29 and become neatly stored and coiled about the same within the interior of the drum.

To facilitate turning of the mount 25 within the drum 10 the cover C is employed. For this purpose each of the pins 29 on the mount 25 extend into and are received by a corresponding round recess 32 provided in the cover C. The recesses 32 are tapered from a large opening at the inner surface 33 of the cover and are centered to register with the three pins 29 on the mount 25. The cover C is adapted to be turned by hand while the drum 10 .is held stationary. In this manner, the turning movement of the cover C is transmitted to the pins 29 and the latter turned with the disc 26 about the shaft 11 to wind the several pairs of emery strips 17 about the mount 25.

The several strips of emory cloth are stored within the drum and each strip 17 has its outer end '35 disposed at approximate alignment with the end 36 of the adjacent bmsh 20.

The cover is secured tightly upon the drum by means of the knurled nut N which is turned down upon the threaded end 14 of the shaft 11 to hold the cover with its inner surface 33 against the surface 38 at the open side of the drum. By turning the nut N slightly, back upon its threaded connection with the shaft 11 the several strips 17 can be pulled to unwind them relative to the mount 25 and to extend them beyond the outer ends 36 of the brushes. Any worn emery surface 22 of the strips can then be clipped (severed) off to present fresh abrasive surfaces 22 to the article to be sanded.

In order to prevent the strips 17 from being pulled out accidentally, that is, unintentionally, or other than when desired, a locking or limit means 40 is provided between the cover and drum. The locking or limit means 40 comprises a plurality of projections or knobs 41 formed on the surface 38 at the open side of the drum and a plurality of recesses 42 formed in the inner surface 33 of the cover C. As best seen in FIG. 3 there is one such knob 41 on each of the six lands or segmental portions of the drum. In the present disclosure I have shown double that number or twelve recesses 42 formed on the inner face 33 of the cover. These recesses 42 are the same radial distance from center as the knobs but extend arcuately in the cover so that any particular set of alternate recesses will register with the knobs 41 on the drum. Consequently, if there is any slippage of the mount by reason of undue pull on the free ends of the several strips of emery cloth ,17 the knobs 41 will ultimately engage the far end of the recesses in which they are disposed and thereby limit and stop further turning of the cover relative to the drum. In this manner the cover will be locked against :further turning and mount 25 will be statically held against turning within the drum.

For purposes of safety, the cover has a peripheral lip 45 depending from its inner face 33 and the wall 13 of the drum has a corresponding annular shelf 46 of reduced diameter to meet and receive the lip 45. The sharp edges at the open upper ends of the slits 16 and the brush mounts 18 are thus covered and guarded against snagging the article being sanded.

From the foregoing it will be appreciated that there is provided a very simple, inexpensive, and efficient manner of supplying emery strips for a rotary sander. The strips can be cut from a larger sheet and secured together in the manner described for mounting as pairs on the several pins 29 of the mount 25. The mount 25 is itself simple yet effective and substantial to provide a storage or supply of emery strips and for securing the latter relative to the sanding drum.

The present invention further provide a novel limiting and locking means between the cover and drum whereby to assure anchorage of the several strips of emery cloth within the drum and against accidental slippage between the mount and the drum.

While I have described my new improvements in the emery ribbons, mount, feed and rewinder for a drum type sander in specific detail, it will be appreciated that the same is susceptible to modifications, alteration, and/ or variations without departing from the spirit of the invention therein. I therefore desire to avail myself of all modifications, alterations and/ or variations as may come within the purview of the appended claims.

What I claim as new and desire to protect by Letters Patent is:

1. The combination with a sander drum having a side wall from which extends a centrally located shaft and a cylindrical peripheral wall having a plurality of circumferentially spaced lands divided by spaced longitudinal slits and a brush extending radially from each land adjacent a respective slit, a plurality of strips of emery cloth 4 and means for mounting the same within said drum com prising:

(a) means for securing said strips of emery cloth in pairs adjacent one end thereof with the abrasive side of each facing in the same direction and each for 5 extension through a respective one of said slits for backing against an adjacent brush, (b) a mount in said drum comprising a disc mounted on such shaft for rotation thereabout, 10 (c) a plurality of pins extending from said disc and each straddled by a pair of said strips where the latter are secured together,

(d) and a cover for said drum mounted on such shaft and having a plurality of recesses registerable with said pins for receiving and engaging the same for turning said pins and disc aobut said shaft for winding said ribbon strips about said mount.

2. The combination with a sander drum having one side closed by a wall from which extends a centrally lo- 20 cated shaft and a concentric cylindrical peripheral will having a plurality of circumferentially spaced lands divided by spaced longitudinal slits and a brush extending radially from each land adjacent a respective slit, a plurality of strips of emery cloth and means for mounting the 25 same within said drum comprising:

(a) means for securing pairs of said strips of emery cloth together adjacent one end thereof with the abrasive side of each strip facing in the same direction,

(b) a mount for said strips comprising a disc arranged on such shaft for rotation thereabout within such drum.

(c) a pin extending from said disc between each pair of said strips and engaging said strips where the pairs of strips are secured together, each of said strips having their free ends extending through a respective one of said slits in the peripheral side wall of said drum and backing against an adjacent brush,

3. The combination with a sander drum having an open sided cylindrical peripheral wall having a plurality of circumferentially spaced lands divided by spaced longitudinal slits and each secured to a side wall having a shaft extending therethrough concentric to said peripheral wall, and a brush extending radially from each land adjacent a respective slit to provide a backing for a plurality of strips of emery cloth each extending through a respective one of said slits from within said drum of means for mounting said strips of emery cloth within said drum comprising:

(a) separate means for securing each pair of said strips of emery cloth together adjacent one end thereof with the abrasive side of each strip facing in a direction to expose its abrasive side opposite to that side thereof bearing against an adjacent brush,

(b) a disc mounted for rotation on such shaft within said drum,

(c) a pin extending from said disc between each pair of said strips for engaging that end of the latter where they are secured together,

(d) a solid cover for said drum mounted on such shaft for closing the open side thereof, said cover having a plurality of recesses registerable with the pins on said disc for receiving and engaging said pins and for turning said pins and disc about said shaft and relative to said drum for winding said strips of emery cloth into said drum,

(e) and a nut threaded on said shaft for securing said cover to said drum.

4. The device of claim 3 including means for limiting relative turning of said cover relative to said drum comprising a projection on the open face of said peripheral wall, and a recess formed on the innerside of said cover engageable by the projection on the open face of said peripheral wall.

5. The device according to claim 3 in which each land has a projection thereon, and means on the inner face of said cover for receiving and engaging one or another of said projections for limiting turning of said cover relative to said drum.

6. In a rotary sander of the type having an open sided cylindrical peripheral wall consisting of a plurality of circumferentially spaced lands divided by spaced longitudinal slits and secured to a solid side wall having a drive shaft secured thereto and extending therethrough, and a brush extending radially from each land adjacent a respective slit providing a backing for a plurality of strips of emery cloth each extending through a respective one of said slits; the combination therewith of means for mounting said strips within said drum comprising:

(a) a staple securing each pair of said strips of emery cloth adjacent one end thereof with the abrasive side of each said strip facing in a common direction for backing against an adjacent brush,

(b) a recess formed on the inner face of the solid side wall of said drum concentric to said shaft and peripheral Wall,

(c) a disc mounted on such shaft for rotation thereabout and seated in the recess formed on the inner face of said solid side wall to dispose the inner face of said disc in flush relation with the inner face of said solid side wall,

(d) a plurality of pins extending from the inner face of said disc, one such pin extending between each pair of said strips where the latter are secured together,

(e) a cover for the open side of the peripheral wall of said drum and mounted on such shaft, said cover having a plurality of recesses formed therein for receiving and engaging the free ends of said pins for turning said pins and said disc about said shaft for winding said ribbon strips about said mount,

(f) and a nut threaded onto said shaft exteriorly of said cover for securing the latter to the open side of the peripheral wall of said drum.

7. The device of claim 6 including means for limiting relative turning of said cover relative to said drum comprising a projection on the open face of said peripheral wall, and a recess formed on the innerside of said cover engageable by the projection on the open face of said peripheral wall.

8. The device according to claim 6 in which each land has a projection thereon, and means on the inner face of said cover for receiving and engaging one or another of said projections for limiting turning of said cover relative to said drum.

9. The combination with a rotary sander of the type having an open sided cylindrical peripheral wall consisting of a plurality of circumferentially spaced lands divided by spaced longitudinal slits and each secured to a solid side wall having a drive shaft secured concentric thereto and extending beyond the open side of said peripheral wall, the said lands each having a brush extending radially outward therefrom adjacent a respective slit and providing a backing for a plurality of strips of emery cloth secured in pairs by having their inner ends joined; an emery strip mount and rewinding means comprising:

(a) a disc mounted on such shaft for rotation thereabout and bearing against the inner face of said solid side wall,

(b) a plurality of pins extending from said disc beyond the open side of said peripheral wall for receiving a pair of said strips where the latter are secured together,

(c) a solid cover for the open side of said peripheral wall having a central bore to receive the extended end of said shaft and having a plurality of recesses registerable with said pins for receiving and engaging the extended ends thereof for turning said pins and disc about said shaft for Winding said strips about said pins,

(d) and means on the extended end of said shaft exteriorly of said cover for securing the latter onto the open side of said peripheral wall.

10. The device of claim 9 including means for limiting relative turning of said cover relative to said drum comprising a projection on the open face of said peripheral wall, and a recess formed on the innerside of said cover engageable by the projection on the open face of said peripheral wall.

11. The device according to claim 9 in which each land has a projection thereon, and means on the inner face of said cover for receiving and engaging one or another of said projections for limiting turning of said cover rela tive to said drum.

References Cited UNITED STATES PATENTS 2,533,619 12/1950 Pokras 51-335 2,600,613 6/1952 Bruner 51-335 2,601,499 6/ 1952 Bruner 51-335 2,709,323 5/1955 Swan 51335 2,771,721 11/1956 Reimar 51335 3,132,452 5/1964 Block 51335 LESTER M. SWINGLE, Primary Examiner D. G. KELLY, Assistant Examiner