US504387A - Apparatus for grinding cutlery - Google Patents

Description

6 Sheets-Sheet '1j.

(No Model.)

lA. JOHNSTON; APPARATUS. F013. GRIN DIN G GU'IVVLERY.

Patented Sept, 5,

` Q ...di

(No Moda.) 6 sheets-sheet 2.

A.. JOHNSTON.

APPARATUS FOR @BINDING GUTLBRY.

No. 504,387. 3 Patented Sept. 5, 18.93.

(NovModel.) 6 Sheets-Sheet 3.'

A. JOHNSTGN. APPARATUS'FOR GRINDING GUTLBRY. No; Y 504,387'.

Patented Sept. 5,

LIJIIIII I `lill-Ill] (.No Model.) 6 Sheets-.Sheet 4. A. JOHNSTON.

APPARATUS' POR GRINDING GUTLERY. No. 504,387, Patented Sept. 5, 1893.

(N Model.) 6 sheets-sheet 5.

AJOHNSTON. APPARATUS FOB. GRINDINGUUTLERY.

` No. 504,387. Patented sept. 5, 189s;

FIC- X-II".

l A6 Sheets-Sheet 6.

'Patgntedsepn 5,1893.

A. JOHNSTON'. APPARATUS Pon GRINDING GUTLERY.

(No Model.)

NITED STATE-s PATENT Ormes..

ALLEN JOHNSTON, OF OTTUMWA, IOWA.

APPARATUS For: GRINDING ouTLERY.

SPECIFICATION forming part of Letters Patent No. 504,387, dated September 5, 1893. Appnoooioo moo ooooboo 1e, iseaf Soriana-149,249. `(No modoi.)

To all whom it may concern):

Beit known that I, ALLEN JOHNSTON, of Ottumwa, in the county ofA Wapello and State of Iowa, have invented a new and useful lmprovement inApparatus for Grinding Cutlery, which is fully set forth in the following specification. y

The present invention relates to the art of cutlerygrindin g, and particularlyto the grinding of articles of various sorts upon which an irregular surface is to be produced by the grinding operation, necessitating an irregular feed, in contradistinction to operations that maybe termed regular, as grinding the flat surfaces of disks, case knives, dac., or the curved surfaces of mandrels, spindles, izc.

The blades of pocket knives may be taken as an illustration of the'class of articles to which this invention has more particular reference. true shape by grinding it must be ground flat on the side for a greater part of its length,

and then gradually rounded ed toward the point. The back is also to be ground flat for the greater part of its length and then rounded toward the point. When the blade is chamfered on one side, as usual with large blades, there is a third operation involving an irregular feed.

One object of my invention is to effect the grinding of these, and similar irregular surfaces, by means of automatic feeding devices. At present (unless the work is held and guided by hand) the sides of pocket knife blades are usually groundby being fed and held against a rotating grinder of greater thickness than the length of the blade. This simply grinds a flat surface leaving the rounding of the blade toward the point to be iinished by hand. It has, however, been proposed to employ an annular grinder, and to feed the knife blade across the same, the grinding beginning at the point of the knife. f

Another operation in the fashioning of pocket knife' blades consists in forming a shouldernear the end which is attachedto the handle. In the manner in which such blades, (and other articles having a similar shoulder) are ground, the shoulder cannot be properly cut by grinding, andv must be finished by hand, the reason being that the corner of the wheel which forms this shoulder To bring such aknife-blade toits is continually wearing away and becoming The invention includes mechanism whereby the operation indicated above may be accomplished. The automatic feeding and workv holding mechanism comprises a slide by which the work is carried and which is capable of moving in any direction in one plane, actuating mechanism for reciprocating the slide to grind the flat surface, and a cam or former (whose shape will depend on the particular contour to be given to the Work) for delecting the slide to grind the irregular or curved portion of its surface. In moving laterally toward and from the grinding surface the slide may swing on a center, or move bodily in guides. The specific motions of the slide are, of course, relative to the grinding wheel,and it is immaterial which of these devices is relatively movable. Special improvements included in this part of the invention will be fully described hereinafter. o

The invention further comprises automatic means for adjusting the wheel with reference to the work holder. The arbor of the grinding-wheel has heretofore been made adjustable lengthwise by means of a hand Wheel.

According to the present invention the wheel is moved forward intermittently by automaticdevices, the amount of motion being sufficient to compensate for wear. Inasmuch as the amount of wear will vary with the hardness of the steel acted upon, aswell as with the composition of the wheel itself, the invention includes'means for regulating the amplitude of motion given to the Wheel at each automatic adjustment. The required amount of motion being ascertained and the adjusting mechanism regulated accordingly, the Workman has no ,further concern with IOO the adjustment of the wheel. Preferably the mechanism is so constructed as to effect an adjustment at the end of each complete movement of the work holding slide, and it is also preferred to provide the machine with an automatic stop to arrest the feed mechanism at the end of each movement. This is desirable because one workman in practice supervises several of these machines, and unless' very watchful he would not always be ready to stop the machine and remove the work at the proper moment.

In order that the invention, and the best mode in which I now contemplate applying the principle thereof, may be fully understood, l will explain the same more in detail, reference being had to the accompanying drawings, which illustrate the construction of a machine having work-holding and feeding mechanism designed for grinding the blades of pocket knives.

Figure I, shows in side view a knife blade after grinding in accordance with this invention. Fig. Il, is alongitudinalsection on line II and Fig. III a transverse section on line III of Fig. I. Fig. IV, illustrates the present mode of grinding the shoulder on the blade. Fig. V, illustrates the improved mode of forming the shoulder wholly by grinding. Fig. VI, is a horizontal section of a machine constructed in accordance with the invention, the section being through the axis of the grinder and the work holding devices being shown in plan. Fig. VII is a front elevation partly in vertical section. Fig. VIIIisa central vertical longitudinal section, the grinding wheel and its arbor being shown in side elevation. Fig. IX, is a vertical cross-section on line IX (Fig. VI) looking to the rear. Fig. X, is a partial plan view of the work holding devices arranged to grind the back of the knife. Figs. XI and XII are details in longitudinal vertical section and transverse section respectively of the work-holding slide and accessory parts. Fig. XIII is a detail of the oscillating segment for conveying motion to the slide. Fig. XIV, is a detail in plan of the automatic stop mechanism for arresting the feed slide at the end of its stroke. Figs. XV and XVI are details illustrating part of the automatic adjusting mechanism for the grinding wheel.

Referring to Figs. I to V, a represents a knife blade ground to proper shape. From the shoulder a', which should he nearly square, to the dotted line III the blade is flat, and from that line to the point a2 it is curved or tapered as shown in Fig. II. If ground straight to the end in the ordinary way the blade would have the same thickness at the point a2 as at the other points along the section of Fig. II, and the curved part of the cutting edge would have to be formed by a separate operation. The back a3 of the blade is ground flat from the right hand end to the dotted line III, and from that line is rounded or curved to the point a2.

The chamfered portion a4 presents the same features as the side of the blade, that is to say, it has a square shoulder and is dat to about the dotted line III, and then curved to the point a2.

In grinding the side of the blade, if the point is first brought in contact with the wheel, and then fed along until the rear end of the surface to be ground reaches the wheel, (as is done in grinding table knives, dac.) the eect will be as shown in Fig. IV, in which b represents part of the grinding wheel. In that method the greater part of the wear occurs at the corner b of the wheel which acts first upon every part of the blade, the wear on the grinding face increasing in degree toward this corner and gradually rounding it, as indicated in the drawings. Consequently, except upon the first few articles ground, the required shoulder cannot be cut by the wheel, rendering another operation necessary.

rPhe improved method is illustrated in Fig. V. According to this plan the blade a. is first fed directly against the wheel extending across and beyond the grinding face as shown. The shoulder is thus cut by the sharp corner, and the blade then fed away from this corner (instead of toward it) until the point of the blade is ground. In practicing this method it will be readily seen that the wear on the face of the wheel diminishes toward the corner b', by which the shoulder is cut, it being the opposite corner b2, which sustains the maximum wear; and that the effect of the abrasion of the wheel in this case is to keep the corner b sharp.

Referring now to the other drawings, the grinding wheel b is of the ring or cup form described in Letters Patent No. 377,201, granted to me January 3l, 1888, and is mounted on a horizontal arbor B, suitably supported in bearings, and provided with the usual fast and loose pulleys. The wheel turns in a trough B adapted to contain water and to supply it by a spout B2 to the interior of the wheel, and the latter is partly inclosed by a guard or casing B3, all substantially as in machines described in previous patents. The work holding slide C rests on a dovetailed support C (Figs. XI and XII) and can reciprocate thereon. This support has a tubular portion C2 IOO IIO

which is pivoted in a socket C3 in the frame (Fig. VII). Consequently the slide C, by the rotary movement of support O', and by its own independent reciprocating movement, is capable of universal motion in a horizontal plane. It can therefore (when properly guided) he moved in, or parallel with the plane of rotation of the grinder, then toward the latter to bring blade ct against it, to begin the operation of grinding at the shoulder (this being the position of the parts as shown in Fig. VI), then back `in a right line, grinding the dat portion ofthe blade, and then in a curved line, compounded of its own motion and the axial motion of the supportC, grinding the curved portion of the blade.

The devices for reciprocating the workholding slide yare in some respects such as have heretofore been used. The novel features of this part of the construction reside mainly, in the automatic guiding of the slide in irregular lines, and in the means for starting and stopping the same. Slide C has on its under side a rack c which engages a pinion c on the end of an upright shaft c2, which has a similar pinion con its lower end. Pinion c3 is engaged and actuated by a segmental arm D (Figs. VII and XIII) which is pivoted at d to the frame and is oscillated by means of a pin d attached to the arm D and entering a cam groove d2 in the drum or cam Wheel D (see Fig. VIII). This gives the slide C a reciprocating motion transversely to the axis of the grinder. Shaft c2 is made in two parts for convenience in removing the slide and its support when desired. The upper part is fastened by a pin 10 to a ring 11, and the lower part similarly fastened by a pin 12 to a ring 13. The two rings are coupled by upright pins 14, 15, which are fast in one of the rings (thelower) and t loosely in holes in the upper. Thus the upper part of the shaft may be readily uncoupled from the lower. This, of4 course, is merely a convenient arrangement, and not an essential feature of the construction.

To grind the side of a blade as in Fig. VI, the slide C must have a motion towardthe wheel in the direction of the axis thereof. To this end a guide arm E is detachably secured by screws or otherwise to slide C. At.

its free end this arm has twopins or rollers e', e2, the latter being carried on the end of a spring E which presses it toward the roller e. Between these rollers or pins is a guideV bar or former F, which controls the positionsy of the slide C axially as it is reciprocated back and forth. It will be obvious from inspection of the drawings that as the rollers e', e2 follow the guide bar F the slide C, while moving lengthwise, will be turned on the axis of shaft c2 as a center when the contour of said bar deviates from a line parallel with the plane of rotation of the grinder, and by giving to the guide-bar or former a suitable outline the work-holding slide may be turned in either direction, and to any desired extent, within certain limits. i

Special importance is not attached to the particular devices described for guiding the work-holder, as these may obviously be modifled, or replaced by other devices capable of performing substantially the same functions. The essential feature or principle of this part of the invention consists in providing automatic means for giving the work-holder an irregular movement.

As shown in Fig. VI the guide, cam, or former F, is secured rigidly to the long lever F pivoted to the frame at f and capable of horizontal oscillation. The ,function of this lever is to swing the work-holder toward the wheel so that the corner b may strike the out, as already explained. This motion is communicated to lever F .in the following way; Said lever has on its under side a recess f which is entered by a wrist-pin f2 on a disk F2. Disk F2 is carried by an upright spindle G suitably supported in bearings in the frame, and having at its lower end an arm G which extends horizontally toward the cam wheel D and has a pin g which enters a second cam groove g in the periphery of said wheel (Figs. VII and VIII). Through these connections the lever F is at the proper moment turned in the proper direction to throw the knife ybladeinto contact with the wheel. The shape of the cam grooves d2 g will, of course, depend upon the character of the work to be done. As shown in Fig. X the lever F and its actuating mechanism are not always essential. In that figure the grinding'of the back of the knife blade is illustrated. In

this instance the guide arm vE is provided Y with a single pin or roller e entering a cam groove e3 in a stationary guide plate E2. This groove is straight for a certain distance and then curved, so that the slide C will vtravel in a line parallelwith the plane of the grinding surface until the curve in the back of the knife blade is reached, and then be deflected so as to keep the curved part of the blade against the wheel. The cam groove here is the obvious equivalent of the cam bar in the other figures.

The means for starting and stopping the feed movement will next be described. Power is transmitted from the shaft 16, having the loose pulley 17, and fast pulley 18, to the shaft 20, having band pulleys 21 (Figs. VI and IX), the speed of the latter shaft being much less than that of the former. On the inner end ofshaft 2O is a small pinion 22 (Figs. VI and VII) which engages and drives a large toothed wheel H which is on the shaft H carrying the cam wheel D. Shaft H is thus driven at a low rate of speed. The belt which drives shaft 16, from which the feed-movement is derived, is controlled bya belt shipper K (Figs. VI and XIV) carried by a rod L, extending backward from thefront of theframe, and having at its forward end an elbow or bend L2 for maniagainst the frame, and tends to push the rod' backward, or in the direction to throw the belt from the fast pulley 18 to the loose pnl-- ley 17. Consequently, whenever the rod is released it at once arrests the feed movement. RodL may be moved in the opposite direc- -tion to start the feed bymeans of a treadle N, rock-shaft N and upright arm N2 (Figs. VII and VIII). The upper end of arm N2 lies between two bosses n n2 on a collar'nwhich isv screwed fast to rod L. Arm N2 is also springy and presses against the collar 'rt which has a at surface onthe side adjacent to said arm, g

as seen in Fig. VII. Rod L also carries a finger or detent m, screwed fast to the rod so IOO I'IO

IZO

as to follow it in either a longitudinal or an axial movement. When the belt is on the loose pulley this detent or finger m bears with slight pressure on the rim H2 of wheel H, the pressure being due to the resiliency of arm N2 bearing as already explained against the collar fn, which at this time is tilted at a slight angle to said arm. To start the feed, the operator puts his foot on treadleN swinging arm N2 forward, moving rod L lengthwise in the same direction, and shifting the belt to the fast pulley. This movement of rod L carries linger m past the rim H2 of wheel H, and the pressure of arm N2 on collar n turns the rod L slightly until the flat face of said collar is parallel with the said arm as shown in Fig. VII. This slight rotary movement of rod L is just sufficient to carry finger m inward so that its free end is caught and held by the edge of rim H2. Consequently, though the operator immediately removes his foot from the treadle, rod L is retained in this position against the pressure of its spring M, and the work-feed continues in operation. Rim H2 is provided at one point with a depression or notch 72. (Figs. VII and VIII). When this notch comes opposite detent m, the latter is no longer held, and spring M at once acts, pushing rod L back and shifting the belt to the loose pulley. This notch is in such position that the feed is arrested at the moment when work-slide C reaches the end of its return movement (to the right in Fig. VII). When now the operator inserts a new piece of work into the holder he puts his foot on the treadle and shaft H begins to rotate, cam groove cl2 begins to oscillate arm D and slide C moves toward the axis of the wheel bringing the work opposite the grinding face of the latter. Pin d now travels for a while in a straight part of groove d2, during which time groove g swings arm G and lever F', as explained above, bringing the blade up against the wheel until the shoulder is cut. When this movement is completed groove d2 swings arm D in the opposite direction, and slide C begins to retreat keeping the blade in contact with the grinder. The movement is at first in a right line, grindinga flat surface on the blade, but as the slide nears theV end of its travel it is deflected by the action of the guide-arm E and the curved part of guide-bar or former F, thus moving in a line which is the resultant of its rectilinear and rotary movements, grinding the curved part of the blade terminating at its point. At this moment the reciprocating movement of slide C ends, and cam groove g causes it to turn away from the wheel, and on the completion of this movement the releasing notch h comes opposite detent m, and the feed is automatically arrested.

In case of any accident necessitating the stoppage of the feed before it completes its movement this can be effected by slightly depressing the bent end L of rod L, turning the latter far enough to release detent m from engagement with rim H2, and permitting spring M to shift the belt from the fast pulley.

The special construction and disposition of parts for effecting the starting and stopping of the feed movement, while advantageous, admit of much modification, the broad novel features of this part of the invention residing in the starting of the feed movement by means of a foot treadle, and the automatic stoppage thereof at the completion of each movement.

The mechanism for automatically adjusting the grinding wheel at intervals to compensate for wear will now be described. The arbor B of the wheel is surrounded by a sleeve P having bearings in the frame in which it can move longitudinally without turning. Sleeve Pis screw threaded externally (Fig. VI) for a portion of its length and engaged by an adjusting wheel Pwhose hub is threaded interiorly, and which is held from endwise movement by two collars pp', which form the bearings of sleeve P. WheelP' has a threaded rim which is engaged by a small pinion q (shown in dotted lines Figs. IX and XV) on a short shaft q which has bearings in a bracket q2. This shaft also carries a ratchet wheel Q with which engages a pawl r, pivoted on a plate R which swings freely on shaft q. Pawl r is held in engagement with ratchet Q by a spring r' (Fig. XV). Plate R receives motion from an upright rod S which passes through a hole in boss R of said plate and is secured by a set screw S. The lower end of the rod S is jointed to an arm T projecting from a rock shaft T (Fig. IX). The forward end of this shaft carries a lug t which lies in the path of a pin t projecting from the rear of Wheel H, (Figs. VIII and IX.) This pin makes contact with lug t once in each rotation of wheel H, depressing it and giving an upward thrust to rod S, this motion being transmitted by the pawl r, ratchet Q and pinion q, to the adjusting Wheel P. The grinding-wheel is thus moved a short distance toward the work holder. It is obviously desirable that this adjustment should be capable of regulation to meet varying conditions of work. This may be elfected by loosening the set screw S and moving the rod S downward to lengthen the stroke of the pawl r, or upward to shorten its stroke.

Many departures maybe made from the details of construction herein described and shown without departing from the spirit of the invention, and some of the elements of the machine may be replaced by devices equivalent in function. For example, I may substitute for a shifting belt and fast and loose pulleys, other Well known means for starting and stopping a shaft.

Having now fully described my said invention, what I claim, and desire to secure by Letters Patent, is-

l. In a machine for grinding articles having an irregular surface, the combination with a grinding wheel, of a work-holder capable of universal motion in one plane, and an irregular guide for controlling the movements of said workholder, substantially as described.

2. In a machine for grinding articles having an irregular surface, the combination with a grinding wheel, of a work-holding slide supported so as to be capable of universal motion in one plane, means for reciprocating said slide in line with the grinding surface of said wheel, and a guide of irregular outline for deflecting said slide from the line of its reciprocating movement, substantially as described.

8. The combination with the grinding Wheel, of a work-holder, a swiveled support therefor, means for reciprocating said slide on its support, a guide for changing the positions of said support and slide while the latter is reciprocating on the former, a movable support or lever carrying said guide, and means for moving said support or lever toward and from the grinding surface of said wheel, substantially as described. Y

, 4. The combination with the grinding-wheel, of a Work-holder, a swiveled support therefor, a pinion on a shaft concentric withV the axis of said support and engaging a rack on said work-holder, means for oscillating said shaft, and a guide controlling the movements of said support on its axis, substantially as described.

5. In a grinding machine for grinding knife blades and other articles having a shoulder thereon, the combination with the grindingwheel, of a work-holder capable of` moving transversely to the grinding Asurface and also parallel therewith, means for feeding said Work-holder toward the grinding surface so as to present the article latwise against the wheel and rst grind the shoulder by the corner of the wheel, and means for subsequently traversing the work-holder with the article in contact with said wheel, across the grinding face thereof and in the direction away from the said corner, substantially as described.

6. In a grinding machine, the combination with the grinding Wheel, of the automatic feed-mechanism for moving the work to, against, and away from the grinding wheel, a starting and stopping device such as abeltshipper, a spring tending constantly to actuate said device in the direction to arrest the feed, a detent for holding said spring during thel feed-movement, and means for automatically releasing said spring and putting the stopping device into operation at the completion of the feed movement when the work is away from the Wheel, substantially as described.

v 7. In a grinding machine, the combination with the wheel, of the feed-slide, driving mechanism for moving said slide toward andfrom the wheel, a spring-actuated rod for disconnecting thegsaid driving mechanism and arresting the feed, a treadle or lever for withdrawing said rod against the pressure of said spring and thus starting the feed, a catch or detent engaging and holding said rod when retracted by said lever or treadle, and means for releasing said catch or detent at the end of the movement of the feed-slide, substantially as described.

8. lThe combination with the grinding Wheel and automatic feed mechanism, of a starting and stopping device such as a belt-shipper, an actuating rod therefor, a treadle for shifting said rod in the direction to start the feed, a detent for holding the rod in this position, and means for releasing the detent automatically at a predetermined moment, substantially as described.

9. In a grinding machine, the combination with Work-holding devices, of a rotary grinder, an adjusting wheel for moving the grinder in the direction of the work-holder, and means for intermittently actuating said wheel, substantially as described.

10. The combination with the work holding devices, of a rotary grinder, a wheel for adj usting said grinder with respect to said Workholding devices, and gearing connected with a moving part ofthe machine for actuating said adjusting wheel intermittently, substantially as described. 1l. In a grinding machine, the combination with the work-holder and its actuating devices, of a rotary grinder, intermittently operating mechanism for moving said grinder toward said work-holder to compensate for wear, and means for regulating the amount of such motion at each adjustment, substantially as described.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

ALLEN JOHNSTON.'

Witnesses:

J. T. HAcKwoRTH, A. G. HARROW.

ICO

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