US2008943A - Grinding machine - Google Patents

Description

Jul 23, 1935.

E. 1. BODEY GRINDING MACHINE Filed May 21, 1934 Patented July 23, 1935 UNITED sTATEs PATENT 1 OFFICE GRINDING MACHINE Edward J. Bodey, Norw omohid Application May 21, 1934, Serial No. 726,719 Q 1 Claim. (01. 51- -92) My invention relates to grinding machines,

especially to such employing a grind-stone or sand-stone in the grinding operation. It is,

especially adapted for providing a compact'rel- 5 atively small unit having a grind-stone sufliciently large and a capacity sufliciently great to perform ordinary grinding jobs thereon for a small shop, tool-room or training school, for sharpening carpenters tools either in the shop or on the job, for use of butchers, for household use, and the like.

It is the object of my invention to provide a device of this character as a self-contained unit comprising the grinding wheel, an electric motor, driving connections between the motor and the grinding wheel, and a tool-holder, all constructed and related for convenient use and for movement from place to place.

The invention will be further readily understood from the following description and claim, and from the drawing, in which latter:

Fig. 1 is a side elevation of my improved device. Fig. 2 is a plan view of the same. Fig. 3 is-an end elevation of the same, partly broken away.

Fig. 4 is a vertical section of a detail of the driving means, taken in the plane of the line 44 of Fig. 2; and

Fig. 5 is a vertical section'of a detail, taken on the line 5-5 of Fig. 2. A base H has a-water-tank l2 integral therewith at one corner and one side thereof. The base and water-tank are preferably a single casting. The water-tank is provided with side walls I3, I45 A bracket l5 extends. integrally from the upper end of one of the side walls, and brackets l6 extend integrally from the upper end of the other side wall of the water-tank.

A shaft l8 extends crosswise of the upper end of the tank. One end of this shaft is journaled in a bearing I9 fixed to the bracket I5, and the other end of the shaft is journaled in a'bearing 20, which is part of a housing 2!, the upper section 22 of which has said bearing therein and is provided with flanges 23 mating with flanges 24 on the lower section 25 of said housing, bolts 26 being received through said flanges and clamping the same to the brackets l6 of the water-tank.

A grinding wheel 3| is secured to said shaft, as by'being clamped between flanges 32, 33 on said shaft, the flange 33 being fixed to said shaft, and the flange 32 being slidable thereon and clamped toward the flange 33 by means of a nut 34 threaded to said shaft.

This grinding wheel is preferably a so-called grind-stone or sand-stone, and is preferably rotatable in the direction of the arrow 35, and is 4 arranged to extend into a body 36 of lubricant or water in the tank, so as to perform so-called wet grinding with the grind-stone to avoid burning w" of tools being ground, one of which is exemplified as a chisel 31. V

A hood M is arranged to be received about the rear upper portion of the grind-stone above'the tank, and is arranged to direct lubricant carried 10 upwardly by the wheel back into the tank, and to arrest the projection of spray from the grindstone. The hood is secured to the tank.

A worm-wheel 45 is fixed to the grind-stone shaft, as by means of a key 46. This worm-wheel 5 is mounted in the housing 2|. It is at the side of the tank above the free side of the. base; A double-threaded worm 41 meshes with the wormwheel and is fixed to a drive-shaft .9 journaled in bearing sleeves 49, 5D in bearings 5!, 52 of the 20 section 25 of the housing 2|. This drive-shaft extends alongside the tank in a direction substantially parallel with the plane of the grind-stone.

An electric motor 55 is fixed to the corner of the base diagonally'opposite to the corner which 25 supports the tank, and projects laterally beyond the end of the tank for locating its axis of rotation in line with the'axis of the rotation of the drive-shaft. The rotor of the electric motor is direct-connected with the drive-shaft 98 by a 30 coupling 58. This coupling is preferably a resilient cushion coupling, comprised for instance of end bushings 59, which are fixed to the respective ends of the shafts 48, El, andare connected by a resilient sleeve 92; which may be of 'one end of the drive-shaft to resist said backlash and to cushion the same so as to prevent noise or jarring action upon the motor.

This resilient cushion is exemplified as a spiral 50 spring 66 having one end thereof received about a positioning lug 67 in a hollow plug 68 screwed into the threaded end 69 of the bore in the bearing 5| which receives the plug 68. The other end of the spring has one side of a ball 19 received I! therein for positioning the ball outwardly from the spring, the other side of the ball being received in an end recess H in the end of the driveshaft 48.

The power of the motor in driving the grindstone has a tendency to move the worm endwise toward the motor, due to the resistance of the worm and worm-wheel in rotating the grind-stone during operation. When the switch for the motor is opened and the electromotive force for the motor is thereby stopped, the grind-stone continues to rotate and then becomes the driver for the drive-shaft and rotor of the motor, and has a tendency to force the worm-wheel axially in the opposite direction, creating jarring and noise,

which is counteracted by the resilient cushioning device 65, so as to provide fora quiet and noiseless stoppage of the grindstone.

A tool-holder I5 is supported on the outer end of the tank in self-contained relation to the rest of the device. It is exemplified as comprising a yoke 16 having depending arms 'I! pivoted to the respective sides of the tank on bolts 78, and adjustably positioned by being provided with arcuate slots 19, through which clamp bolts extend, these clamp bolts being threaded into pads 8| on the respective side walls of the tank, the depending arms being clamped to the side walls in the adjusted positions of the yoke. Only one of these positioning devices may be employed.

A supporting rod 84 is fixed in lugs 85 at the respective ends of the yoke, and has a tool carrier 86 pivoted thereon on bearings 8'1. The tool carrier has a tool-receiving gap 88 having end walls 89, a lower wall 90 and a top plate SI releasably fixed to the end walls by screws 92. An intermediate clamp plate 93 is located in the gap, which also contains the tool 31. A clamp screw 94 is threaded in a threaded hole 95 of the upper plate for clamping against the clamp plate, clamping the tool between the clamp plate and the lower wall.

Anadjusting screw 96 is threaded in 2. lug 91 of the pivoted yoke, and is arranged to rest upon a track 98 of the yoke and to slide along said 7 track with the yoke.

I The yoke is adjustable on its pivot toward the grinding wheel as the grinding Wheel wears, so

tool at proper angle to provide the cutting end with a suitable taper or under-cut grinding.

The carrier with the tool therein is shifted along the rod 84, with the lower end of the adjusting screw 96 riding on the track 98 for passing the cutting edge of the tool back and forth across the face of the grinding wheel in grinding the tool, with the tool maintained in correct position for grinding. As the tool is ground the adjusting screw 96 is adjusted to bring the cutting end of the tool closer to the grinding wheel, or the tool may be adjusted lengthwise in its carrier.

The tool is readily examined by swinging the carrier rearwardly upon the rod 84, with the assurance that upon swinging back the carrier into normal position the tool will reassume its exact relation with the grinding wheel after examination. 7

My improved device is simple and compact. The frame is sufficiently heavy to hold it steady during operation. It provides means for sharpening tools without the danger of burning the cutting edges thereof. ,It is readily moved bodily without disturbance of the relations of any of its parts, and the grind-stone, the motor and the driving connection between the motor and the grind-stone are such that a very small motor provides ample power for the grind-stone, and so that the high speed of the motor is reduced in one step for proper rotative speed of the grindstone in the grinding operation.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

In a grinder, the combination of an elongated base, an upwardly extending support at one corner and one side of said base comprising spacedapart walls, a grinding wheel shaft journaled on said support and extending crosswise of said base, a grinding wheel between said walls secured to said shaft, an electric motor at the diagonally opposite corner of said base having a rotor whose axis of rotation extends lengthwise of said base, said motor having a frame overlapping the plane extended lengthwise of said elongated base in which said support is located, a drive-shaft direct-connected with said rotor and extending lengthwise of said base at the side of said upwardly extending support, a worm secured to said drive-shaft, and a worm-wheel secured to said grinding wheel shaft and meshing with said worm, said worm, worm-wheel and drive-shaft located above the opposite side of said elongated base.

EDWARD J. BODEY.

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