Untitled record

Application filed January 19,1891, Serial No, 378,238. (No model.)

To all whom it may concern:

Be it known that I, Edward A. Jones, a subject of the Queen of Great Britain, residing at Tonawanda, in the county of Erie and 5 State of New York, have invented a new and useful Improvement in Machines for Grinding Metal Balls, of which the following is a specification.

This invention relates to a ball-grinding io machine in which metallic balls suitable for use in ball-bearings are ground and polished between two disks.

My invention has for its objects to improve the construction of the lower grinding-disk, 15 so as to increase the effectiveness of its grinding-surface, and also to provide an automatic device for depressing and raising the upper grinding-disk.

In the accompanying drawings, Figure 1 is 20 a sectional elevation of my improved ballgrinding machine. Fig. 2 is a horizontal section in line x x, Fig. 1. Fig. 3 is a fragmentary front elevation of the raising and depressing mechanism. Fig. 4 is a horizontal 25 section in line z z, Fig. 1. Figs. 5 and 6 are fragmentary vertical sections showing modified forms of the lower grinding-disk.

Like letters of reference refer to like parts in the several figures.

A represents the bed-plate of the machine, which is supported on legs a a.

B and E represent the disks between which the balls are ground and polished. The lower disk B consists of a series of metallic divis35 ion-rings ύ, arranged concentrically and separated from each other by annular spaces, which are filled with emery or other suitable abrading material. The emery is compacted in the annular spaces, so as to form solid 40 rings or fillings &' between the metallic rings.

The emery fillings are provided in their upper sides with annular grooves b², of halfround form, in which the rows of balls are seated. The emery rings may be made of 45 greater or less width, but should be wide enough to form effective abrading-surfaces for the balls, whereby the latter are ground and polished when rolled between the disks. The metallic division-rings extend above the em50 eiy rings and form the sides of the grooves which receive the balls. The division-rings are somewhat harder than the emery in the bottom of thegrooves,which causes the grooves to wear downwardly. This prevents the balls from moving laterally or radially with refer- 55 ence to the center of the disks and wearing the grooves wide, which would cause the balls to be ground irregularly.

C represents an annular frame or trough which contains the division and emery rings 60 and an annular supporting-plate O', arranged on the bottom plate c of the trough between the inner and outer walls c' c² thereof,whereby the plate 0' is guided vertically.. This frame or trough rests upon the bed-plate and is pro- 65 vided with adjusting-screws d, arranged in the base-plate of the frame and bearingagainst the lower side of the supporting-plate,whereby the latter and the grinding-disk resting thereon are adjusted vertically. The adjust- 70 ing-screws extend through enlarged openings in the bed-plate, which permits the grindingdisk to be adjusted from below and also holds the same against rotary movement.

In the construction of the lower grinding- 75 ring represented in Fig. 1 the emery rings are equal in width to the balls which are being ground, so. that a large portion of each ball is presented to the grinding-surface of the emery ring. g₀

In the modified construction represented in Fig. 5 the emery rings are somewhat narrower than the balls, and the metallic division-rings extend underneath the balls, so as to form a portion of the bottom support for 85 the balls. This arrangement causes the division-rings to retard both the lateral and downward wearing of the grooves and requires less frequent renewal of the emery rings. ₉o

In the modified construction represented in Fig. 6 the lower grinding-disk consists of one solid metallicdisk having the annular grooves for the balls cut in its upper surface, and each of the grooves being provided in its bot- 95 tom with a channel d', which is filled with emery or similar abrading material. In each case an abrasive bearing-surface is provided for the lower portion of the balls, which accelerates the grinding and polishing of the 100

455,879

M represents a sliding weight arranged on the rear arm of the lever, whereby the rear arm is depressed. This weight, is provided with an opening m, through which the lever 7c passes and which contains rollers m', which rest upon the lever and enable the weight to slide easily.. The movement of the sliding weight on the lever is limited by adj ustable stops m² m^s, secured to the rear arm of the 75 lever and arranged on opposite sides of the weight.

N represents a fulcrum-bolt, which serves as the fulcrum of the. lever K when the latter is in the position for depressing the upper.80 grinding-disk. This bolt is arranged withits head in an undercut groove n, formed in an adjusting-bar n', and passes through an opening formed in the outer arm of the lever. The lever and adjusting-bar are pivotally secured 85 together by a clamping-nut n², applied to the screw-threaded end of the fulcrum-bolt and bearing against the side of the lever. The adjusting-bar is provided on one side with a screw-threaded shank 0, which passes through 90 an opening formed in a lug 0' on the front side of the collar i, and is secured thereto by a clamping-nut o², applied to the end of the shank. The shank and clamping-nut of the adjusting-bar enable the latter to be adjusted 95 to the position of the fulcrum-bolt N in changing the fulcrum of the lever K.

P represents a fulcrum pin or roller secured to the side of the overhanging arm underneath the rear arm of the lever K. This pin 1 ctor roller serves as a fulcrum for the latter when it is desired to raise tlie upper disk for the purpose of removing the balls and placing a new supply upon the lower disk. In the position of tlie parts represented in Fig. 105 1 the lever is fulcrumed on the bolt N, which causes the sleeve carrying the shaft and upper grinding-disk to be depressed, owing, to the pressure of the weight at the opposite end of the lever. As the upper disk wears no and becomes lighter the weight is moved toward the outer end of the lever by adjusting the stop m² to increase its leverage and compensate for the loss in the pressure resulting from the wearing of the upper disk. During 115 the downward movement of the lever, as the upper disk wears away, its fulcrum-bolt, is permitted to move outwardly by a slight, turning of the adjusting-bar on its pivot. The groove in the adjusting-bar permits.the 120 fulcrum-bolt to be adjusted vertically in accordance with the thickness of the upper grinding-disk. When it is desired to raise the upper disk, the fulcrum-bolt is loosened, which permits the front arm of the lever to 125 rise and the rear arm to. descend until the latter rests upon the fulcrum pin or roller P.

s Upon lowering the rear arm of the lever i slightly below a horizontal position the weight ; M slides toward the outer end of the rear arm 130 ’ by gravity, and thereby increases the lever. age of the latter) This increased leverage latter and retards the lateral wearing of the grooves. ।

Heretofore the emery has been introduced i between the grinding-disks in a powdered ¹5 form for the purpose of grinding the balls; ] but the centrifugal action of the rotating up- : per disk and the balls caused the powdered i emery to work over the sides of the disks and required frequent renewal of the emery, ι io By forming a bed of solid emery to support the balls a constant abrading-surface is furnished, which, overcomes this difficulty and causes the balls to be ground more uniformly.

The upper grinding-disk E consists of one 15 solid ring which extends downwardly between the walls of the annular frame and bears upon the balls.

F represents a vertical shaft whereby a rotary motion is imparted to the upper grind20 ing-disk. This shaft is arranged within both grinding-disks and axially in line therewith and is journaled near its lower end in a bearing/, formed centrally in the bed-plate of the machine.

G represents a supporting-plate whereby the upper disk is secured to the shaft. The central portion of this plate is provided with a hub g, which is secured to the shaft. The upper disk is provided on its upper side with 30 bosses or lugs h, which enter openings' h', formed in the upper supporting-plate, and the disk is secured to the latter by screw-bolts 7i², passing through washers 7i^s, arranged on the supporting-plate and entering the bosses 35 of the upper disk.

The upper end of the shaft is-journaled in a sleeve I, arranged to slide vertically in a collar i, formed at the upper end of an overhanging arm J, secured to one side of the 40 bed-plate. The vertical shaft is- preferably made in two sections for convenience in disconnecting the parts, the adjoining ends being connected by means of a coupling-collar j, secured to the ends of the shaft-sections by 45 means of transverse pins j'j². The sleeve I bears with its ends against the hub of the upper disk and the coupling-collar, whereby lengthwise movement of the sleeve on the shaft is prevented. The upper portion of the 50 shaft is provided with a bevel-gear/, for the purpose of transmitting motion to the upper grinding-disk. The gear-wheel is secured to the shaft by means of a key or spline/, which enables the shaft to move lengthwise 55 through the gear-wheel, but compels them to rotate together.

K represents a lever whereby the upper grinding-disk can be depressed for grinding the balls or raised for the purpose of remov60 ing the balls. This lever is provided between its ends with a boss 7c', which is arranged in a vertical slot k², formed on one side of the collar i of the arm J, and is pivotally secured to the side of the sleeve I by means of a bolt 65 Z engaging with one of a vertical series of openings Z', formed on the side of said sleeve.

455,879 causes the rear arm to continue its downward movement and swing on the roller P as a fulcrum, thereby raising the front arm of the lever and lifting the upper disk connected .5 therewith. The adjusting-bar is preferably curved, so as to permit the fulcrum-bolt to move freely in the groove of the adjustingbar when the lever swings on the roller P as . a fulcrum. In this manner the weight M is to utilized either to depress or raise the upper grinding-disk, thereby enabling the machine to be manipulated very easily. When it is desired to again depress the upper disk, the front arm of the lever is depressed by means 15 of the handle q at the front end until the upper disk bears upon the balls and the rear arm of the lever is raised from the fulcrumroller. Upon tightening the bolt N on the adjusting-bar said bolt again acts as the 20 fulcrum of the lever, which causes the weight to depress the upper disk. By alternately locating the fulcrum on the bolt Ν' and roller P it acts alternately in the capacity of a first and second class lever. The in25 stant the rear arm of the lever is raised above a horizontal position the weight slides inwardly toward the fulcrum, thereby decreasing the leverage. In this manner a small leverage and a correspondingly light 30 downward pressure can be applied to the balls in addition to the weight of the upper disk, while a larger leverage is used when it is desired to raise the upper disk. This change in leverage is automatically effected 35 by the sliding of the weight M when the rear arm of the lever rises above or falls below a horizontal position. If desired, the weight may be rigidly secured in place after adjustment by means of a set-screw ?»⁴.

The boss of the lever and its pivot-bolt I are free to move vertically with the sleeve I, owing to the slot fe².' The pivot-bolt I is placed in one of the higher openings 1' as the upper disk becomes worn, so as to retain its rela45 tive position to the fulcra of the lever.