US2073400A

US2073400A - Stone polishing machine

Info

Publication number: US2073400A
Application number: US64431A
Authority: US
Inventors: William G Cumming
Original assignee: GRANITE CITY TOOL Co
Current assignee: GRANITE CITY TOOL Co
Priority date: 1936-02-18
Filing date: 1936-02-18
Publication date: 1937-03-09
Anticipated expiration: 1954-03-09

Description

March 9, 1937. w. e. CUMMING STONE POLISHING MACHINE Filed Feb. 18, 19 36 wilza Patented Mar. 9, 1937 PATENT OFFICE STONE POLISHING MACHINE William G. Cumming,

Barre, Vt., assignor to Granite City Tool Company, Barre, Vt., a corporation of Vermont vApplication February 18, 1936, Serial No. 64,431

1 Claim.

This invention relates to stone polishing ma.- chines of. the type employing polishing wheels which rest on the stone and rotate about vertical axes, the wheels comprising a disk having eccentric scrolls attached to their lower faces and operating upon the stone through the medium of iron shot or other abrasive material.

Objects of the invention are to polish convex, concave or other warped surfaces, to facilitate the manipulation of polishing wheels of the type referred to, to reduce the vibration and tendency of the wheels to chatter, to increase the quality and rate of polishing, to prolong the life of such machines and generally to improved the art of stone polishing.

The present invention comprises a horizontal beam with means for adjustably supporting the beam for endwise movement, one end of the beam carrying means for supporting a polishing wheel for rotation about a vertical axis and the motor for driving the wheel preferably being mounted on the other end of the beam. The beam is supported intermediate its ends for horizontal swinging and for vertical tipping. The

preferred means for this purpose comprises a support pivoted about a horizontal axis to a stub shaft extending upwardly into a sleeve containing bearings for the shaft, at least one bearing being arranged to support the shaft in the sleeve.

In the preferred embodiment the supporting means is carried by a crane which is adjustably mounted on an upright so that it may be raised and lowered and also swung horizontally.

The invention also comprises means for adjusting the aforesaid beam endwise on its support. This means comprises a part fast to the beam, a part fast to the support and interconnecting means for producing relative movement of the parts toward and from each other. More specifically said means preferably comprises cable wheels mounted on the beam on opposite sides of the support. together with a cable extending around the wheels and having its ends attached to the support and means for rotating one of the wheels. The wheel to be actuated is preferably a sprocket wheel and at least that portion of the cable cooperating with that wheel comprising a chain meshing with the sprocket wheel.

Other aspects of the invention will appear from the following description and the accompanying drawing of one concrete embodiment. In the drawing,

5 Fig. 1 is a. front elevation of the machine;

Fig. 2 is a section on line 2-2 of Fig. 1; and

Fig. 3 is a section on line 3-3 of Fig. 2.

The particular embodiment of the invention chosen for the purpose of illustration comprises an upright 1 upon which the crane 2 is mounted for vertical movement and also horizontal swinging. Vertical movement of the crane is facilitated by means of two rollers 3 engaging opposite sides of the upright I and the crane is maintained in horizontal position by means of a brace 4 connected at its lower end to a sleeve 5 surrounding the upright I. Two sheaves 6 are mounted on the upper end of the upright by means of a bracket 1 and another sheave 8 is mounted on the upper side of the crane 2. A winding drum 9 is mounted on the crane adjacent the upright and is arranged to be rotated by means of a motor Ill connected to the winding drum through the medium of .a worm H and worm-wheel l2. A cable [3 extends around the sheaves 6 and 8 and around the drum 9, one end of the cable being connected to the bracket 1 and the other end to the drum 9. Thus when the drum 9 is rotated in one direction the crane is lifted by winding the cable around the drum, and when the drum is rotated in the opposite direction the crane is lowered by unwinding the cable.

Depending from the outer end of the crane 2 is a sleeve I4 containing two anti-friction bearings l5 and NS for the swivel shaft I1, the upper bearing being arranged to support the shaft. Mounted on the lower end of the swivel shaft IT, by means of a horizontal pivot pin I8, is a support l9 carrying four rollers 20. Mounted upon these rollers is a horizontal beam comprising two channel members 2| having their flanges directed inwardly over and under the rollers 20, the two channels being tied together by straps 22 underneath the channels. Mounted on the upper side of the horizontal beam on opposite sides of the support I9 are a sheave 23 and a sprocket wheel 24. Extending around these two wheels is a cable having its opposite ends connected to the support Hi, the portion 25 of the cable cooperating with the sheave 23 comprising steel wire and the portion 26 of the cable cooperating with the sprocket wheel 24 comprising a chain meshing with the teeth of the sprocket wheel. The sprocket wheel 24 is arranged to be rotated by means of a handwheel 21 kinematically interconnected with the sprocket wheel through the medium of a shaft 28 and worm gearing 29.

Mounted on one end of the beam 2| is a gear casing 30 containing bevel gears 3|. Extending downwardly from the gearing 3| through a bearing in the lower side of the casing 30 is a shaft 32 which is connected to the polishing Wheel 33 through a flexible coupling 34. Adjacent the casing 30 is an abrasive reservoir 35 having an outlet duct 36 for delivering "abrasive through openings in the top of the polishing wheel 33. Mounted on the other .end of the beam M is a motor 31 'whichis interconnected with the gearing 3| through the medium of shaft 38 and

flexible couplings

39 and 40. By providing a flexible coupling at each end of the shaft 38 vibration of the apparatus is greatly reduced.

The beam 2| carries a bail-like handle 4| for manipulating the wheel 33 over the slab of stone 42 mounted on block 43 within an enclosure 44. The beam also carries, adjacent the handle 4| and the handwheel 21, two

electrical control devices

45 and 46 for the motors I0 and 31 respectively.

From the foregoing it will be evident that a single operator standing outside the enclosure 44 adjacent the'handle ll can readily manipulate the entire apparatus'from this one location, raising and lowering the beam by means of motor I!) and control 45, starting, and stopping the wheel by means of motor 31 and control 46, adjusting the beam lengthwise on the support I 9 by means of the handwheel 2'! and swinging the beam 2| horizontally by means of thehandle 4|. Thus the polishing wheel 33 may readily be placed on the slab ofstone 42 and then easily manipulated over the upper surface of the slab, the motor 37 tending to counter-balance the parts carried by the other end of the beam. It will also be evident that my improved machine is especially adapted to polish warped surfaces, or fiat surfaces which are not level, as well as flat level surfaces, without any change in the machine in changing from one type of work to another.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claim.

I claim:

A stone polishing machine comprising a normally fixed overhead carrier, a substantially ver tical sleeve having its upper end fixedly secured to the carrier, a freely rotatable swivel shaft within the sleeve, antifriction bearings for the swivel shaft disposed within the sleeve adjacent the opposite ends of the latter, one at least of said bearings being constructed and arranged to support the weight of the swivel shaft and parts carried by the latter, a support, and a pivotal-connection so uniting the support to the lower end of the swivel shaft as to permit the support to tilt about a horizontal axis, a. beam structure including a pair of substantially par-allel rigidly connected channel members each having its flanges directed inwardly toward the other channel member, two pairs of rollers mounted on the support, said pairs of rollers being disposed between the flanges of the respective channel membersfbearing means adjacent to one end of the beam structure for' a normally vertical polishing wheel shaft, a polishing wheel on the lower end of the latter shaft, means adjacent to the opposite end of the beam structure for supporting a driving motor, drive connections extending longitudinally of the beam structure from the motor to the polishing wheel shaft, and manually actuated means, reacting between the support and beam structure whereby the latter may be moved longitudinally relative to its support.

G. CUMMING.