US2105872A - Grinding machine - Google Patents

Description

Jan. 18, 1938. A. WARNER GRINDING MACHINE Filed July 23, 1934 6 Sheets-Sheet 1 WEE U5 flrifiazi 77 47 77 er.

Jan. 18, 1938.

A. WARNER GRINDING MACHINE I 6 Sheets-Sheet 2 Filed July 23, 1934 M EJ712315 /%w Jan. 18, 1938. WARNER 2,105,872

' GRINDING MACHINE Filed .July 25, 1954 6 Sheets Sheet 3 Jan. 18, 1938.

A. L. WARNER 2; 105,872

GRINDING MACHINE I Filed July 25, 1934 6 Sheets-Sheet 4 n-18, 193s ALWARNER 22,105,812

GRINDING MACHINE Filed July 25, 1934 6 Sheets-Sheet 5 Y Jan. 718, 1938. A. WARNER GRINDING MACHINE Filed July- 23, 1934 6 Sheets-Sheet 6 Patented Jan. 18, 1938 UNITED STATES ATENT OFFECE GRINDING MACHINE Application July 23, 1934, Serial No. 736,534

3 Claims.

This invention relates to a grinding machine primarily designed for grinding bevelled edges upon metal blanks for producing cutting blades or knives for a harvester or mowing machine but susceptible of other uses.

It is an object of this invention to provide a grinding machine in which the grinding effect is progressively decreased until the proper cutting edge has been produced in which both bevelled edges of a blank or blade may be ground and in which the rear faces of the blades may be ground or rendered smooth and in which the ledger plates for co-action with the blades may also be ground.

In grinding bevelled edges upon such blanks, it is desirable to first effect the major reduction of one edge of the blank and then to perform the finishing grinding with less pressure and after the finishing grinding has been completed to have the blades move out of contact with the grinding element. Thereafter, the blades may be reversed for grinding the other edge.

In order to accomplish the foregoing objects, the blank or blade carrier and the grinding element are so mounted that the planes of rotation thereof have approaching periods and receding periods. More specifically the blank carrier is mounted upon a shaft that is tilted in both a vertical direction and a horizontal direction with respect to the plane of the grinding element.

The invention comprises the novel structure and combination of parts hereinafter described and more particularly pointed out and defined in the appended claims.

In the accompanying drawings which illustrate a preferred form of this invention and in which similar reference numerals refer to similar features in the different views:

Figure 1 is an elevational view of a grinding machine involving this invention.

Figure 2 is a top plan view of the grinding machine.

Figure 3 is a sectional view taken upon the line III-III of Figure 2 looking in the direction of the arrows.

Figure 4 is a part sectional and part elevational view taken upon the line IV-IV of Fig. 3 looking in the direction of the arrows.

Figure 5 is a fragmentary elevational view of the carrier shaft assembly.

Figure 6 is a sectional view taken upon the line VIVI of Fig. 2 looking in the direction of the arrows.

Figure '7 is an enlarged sectional view taken upon the line VII-VII of Fig. 2 looking in the direction of the arrows and showing the carrier wheel in elevation with parts removed.

Figure 8 is an enlarged sectional view taken upon the line VIII-VIII of Fig. 2 looking in the direction of the arrows.

Figure 9 is an enlarged sectional view taken upon the line IX-IX of Fig. 1.

Figure 10 is a sectional view through the grinding element illustrating in diagrammatic form the relation of the blades thereto at various points in the vertical tilted relation of the carrier.

Figure 11 is a fragmentary plan view of the grinding element illustrating in diagrammatic form the passage of the blades thereover for bevelling both edges.

Figure 12 is a sectional view of the grinding element illustrating in diagrammatic form the path or orbit of the edge of a blank during the grinding operation.

In referring to the drawings which illustrate the preferred embodiment of this invention, it will be observed that the machine includes a base I mounted upon suitable legs or standards i as shown in Figs. 1, 3, and 6. This base I is provided with a pair of spaced upstanding flanges 2 for a purpose that will later appear. The base is also provided with a dovetail groove 3 for slidably receiving an upright bearing 4 shown more clearly in Figs. 3 and 6.

The bearing 4 supports the grinding shaft 5 which is journalled therein by suitable roller bearings 6 held in place by suitable cover plates 1. The bearing t is formed with a depression or recess 8 between the cover plates 1 for accommodating the driving pulley 9 upon the shaft 5. The shaft 5 projects beyond one end of the bearing for supporting a circular and hollow grinding element Ill.

The grinding element is supported upon the end of the shaft 5 by means of a carrier disk II which is provided with a hub portion l2 fitting over a collar l3 keyed upon the shaft. The hub portion has an annular flange l4 that is directed over a portion of the end of the collar It. A washer l5 upon the shaft 5 is held against the flange M by means of the nut l6 upon the end of the shaft. The carrier disk H has an outer periphery in the form of a flange l'l extending parallel to the hub l2 and forming therewith an annular recess in which a portion of the circular grinding element is secured. A bracing ring l8 may surround the flange 11. The grinding element is shown enclosed by the telescopic cover members [9 and 20, supported by arms attached to the frame. The cover member 18 is cut away upon its outer face upon an arcuate line '2! (Figs. 1 and 9) extending under the fluid supplying pipe 22 so that the blanks or blades to be ground may be brought into contact with the grinding element. It will be noted from Fig. 9, that the fluid is forced from the pipe 22 by considerable pressure and strikes the grinding element as well as the blank, substantially at the juncture.

In order to longitudinally adjust the grinding element to take up wear, there is provided an adjusting mechanism which is best shown in Figs. 3 and i. In referring to these figures, it

will be noted that the slidable bearing 4 is 0 1,

vided with a lug 24 that extends through a slot 25 in the base. A shaft 26 which is -journalled in the base has one end threaded in the lug 24. A worm gear 2'! is secured upon the shaft 26 in a slot 28 provided in the base I. A worm gear 29 meshes with the gear 27. The worm gear 29 is secured upon a shaft 36 journaled in a suitable bracket 3i secured to the inner side of a standard I and in a bearing 32 upon the outer face of said standard. The outer end of the shaft carries a handwheel 33. It will be evident that by rotating the handwheel, the shaft 26 will be rotated for shifting the bearing 4 and the grinding element for varying its relation with the blanks that are rotated over the outer face of the grinding element by means of a carrier wheel 33. The carrier wheel 3G is best shown in Figs. '7 and 8. It is keyed upon a rotatable sleeve or hollow shaft 35 which is journaled in bearings 38 and 39. A nut 3'! upon the end of the sleeve 35 abuts the hub of the carrier wheel and limits its movement toward the left. The bearing members 38 and 39, (Fig. 6) in which said shaft 35 is journaled are secured together by screw bolts 48, and they are attached to the aforementioned flanges 2 by means of screw bolts 4| and 52. A shim i3 is positioned between the bearing member 39 and the right hand flange 2 as viewed in Fig. 2 through which the bolt 4| passes. This shim 53 will cause the axis of the hollow shaft 35 to be slightly oblique to the axis of the grinding shaft 5. This will slightly tilt the carrier head laterally toward the grinding element.

The holding bolt A2 extends through a slot 44 in the flange 2. The center of this slot 45 may have the same elevation as the center of the holding bolt ll so that when the bolt 42 drops to the bottom of the slot, the forward ends of the bearings 38 and 33 may drop downwardly in 1 a vertical plane upon the bolt 4! as a pivot, thuswise giving the hollow shaft 35 a slight vertical tilt in a downward direction adjacent the grinding element. Thus it will be seen that the axis of the carrier shaft, is tilted in a downward direction and in a lateral direction toward the grinding element for a purpose that will later more fully appear.

Reverting now to Figs. 7 and 8 which show the blade or blank carrier 34 it will be observed that the carrier consists of a disk-like structure having a hub 34* keyed to the hollow shaft 35 and embracing a series of blocks 45 with downwardly and inwardly sloping faces 46. In the present instance the blocks 45 are shown as attached to the disk proper.

Upon the sloping faces 46 of the blocks 45 are attached blank holders 4! and 68 alternately arranged. While these holders may be designed to hold any article to be ground, in the present instance, they are designed for holding blades for harvester or mowing machines and presenting such blanks or blades to a grinding element for bevelling the edges for cutting purposes. The holders are designed so that the blanks or blades can be inserted and removed in radial directions. To this end the holders which may consist of suitable metal are provided with inwardly directed recesses '49 each of which has three supporting lugs, two at the forward end designated 50 and one at the rear end designated 52. These lugs may be integrally formed with the holders. It will be noted that the bottoms or ends of the recesses in the holders 4'! slope in one direction while the bottoms or ends of the recesses in the holders 48 slope in the opposite direction and that the holders 4'! and 48 are alternately arranged. Thus after a blade has been ground upon one edge, it may be removed and placed in a different holder for grinding the other edge. Thus the blades 52 shown in the holders it in Fig. '7 are designed to have one edge ground. The blades may then be transferred into the holders ll to have the other edge ground or vice versa.

A series of clamping members 53 are provided for clamping the blades in the holders and against the lugs 53 and 5|. Each clamp 53 is mounted upon a bolt or rod fi l that slidably extends through the carrier disk 34 and that is provided with a head 55 that forms an abutment for a coil spring 55 positioned between such head and the carrier disk. The heads 55 of said rods 54 are forced by said spring against a stationary cam ill mounted upon a stationary shaft 36 extending through the sleeve 35. The face of the cam has a short advanced portion 58 and a long receded portion 59 (Fig. 8) with the result that when the head of a bolt is opposite the receded portion, its spring 58 will retract the bolt and press its clamp 53 against the blade. However, when the head of a bolt 35 strikes the advanced portion of the cam, the bolt will be shifted to release its clamp as shown in Fig. 8 whereby a blade may be removed or inserted.

The hollow drive shaft 33 carries a spur gear 60 (Fig. 5) that is driven by a pinion ii! secured upon a driving shaft 82 journaled in the frame. The blade carrier and the grinding element are hence operated from different sources of power and at different speeds in opposite directions.

In grinding a blade, the edge of the blade will travel in a plane that inclines in a lateral direction toward the grinding element and that also inclines in a vertical direction toward the grinding element due to the lateral and vertical inment and causes the blank to travel in an inclined plane toward the grinding element when it approaches the same.

In Fig. 12, the full line 64 represents the axis of the blade carrier shaft 35 when the same is in horizontally tilted relation to the grinding shaft 5, while the dotted line 63 represents the axis of shaft 35 when the same is in parallel relation to the grinding shaft. The lines 65 and 66 represent one-half of the orbit projected upon a horizontal plane that the blade edge will traverse during a rotation of the blank carrier due to the double tilt of the blade carrier shaft. The line 65 represents the line of the finished edge of a blade illustrating its inward movement toward the grinding element while the line 66 represents the return movement of the finished or ground edge. Since the line 65 represents the finished or ground edge, the material which is to be ground away will be located between the line 65 and the grinding element or inside the line 65. In other words the edge of the rough blank will be inside of the line 65 and adjacent said grinding element. Thus it will be seen that the blank moves in an inclined plane toward the grinding element for grinding away the major portion of the edge, but it would move away from the grinding element too soon for producing a good cutting edge if it were not for the vertical tilt of shaft 35 that positions the lower portion of the carrier closer to the grinding element. In other words, the vertical tilt of the blank carrier causes the blank to gradually move toward the grinding element as the major portion of the edge of the blank is being ground off. It will, of

course, be understood that this gradual move-.

ment takes place when a blank on the carrier wheel approaches the grinding element through the rotation of said carrier Wheel.

In Fig. 10, there is shown in diagrammatic form the manner in which the blanks or blades gradually move toward the grinding element. Fig. 11 illustrates the space on the grinding element traversed by the blanks during the grinding operation, and it will be noted that the vertical tilt makes it possible to grind a good cutting edge upon the blanks before they pass out of contact with the grinding element.

It will be noted that certain blanks are having one edge ground while the other blanks are having the other or opposite edge ground. It will, of course, be understood that when one edge of a blank has been bevelled to a cutting edge, the blank is removed from its holder and placed in an adjacent holder or any other holder that will reverse the position of the blank for grinding or bevelling the other edge.

In the operation of this machine, it is only necessary to set the grinding element and blank carrier in operation and insert the blanks in the blank holders when the clamps 53 thereof are in their inoperative positions, and remove such blanks as have one edge bevelled or ground when said clamps are released. The blanks with one edge ground may then be placed in a reversed holder as previously set forth for grinding. or bevelling the other edge. With reference to Figure 1, it will be noted that the work holder only overlaps a portion of the grinding element. In its rotation, the blanks will gradually approach the overlapped portion of the grinding element, but this movement will be more gradual the nearer the blanks get to the grinding element, for the blanks are then travelling along the flattest side of an elliptical curve. At about the point Where a blank leaves the grinding element, it begins to recede away from the grinding element. Thus it will be seen that the blanks move in a substantially elliptical path or curve. During operation, as viewed in Figure l, the work holder rotates in an anti-clockwise direction while the grinding element moves in a clockwise direction however at a different rate of speed than the work holder as there must be relative rotation between the two. Preferably, the grinding element rotates faster than the work holder.

It will be evident that the feature of tilting the blank carrier as herein set forth will result in more finished cutting edges upon the blanks, in that it slightly increases the finishing period in grinding the blanks.

I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

1. In a machine for grinding blanks, a disklike work holder having blank holders upon one side face, a clamping member cooperating with each blank holder, a rod secured to each clamp and slidably extending through said work holder in a transverse direction, heads upon said rods, springs between said heads and work holder, a hollow shaft for supporting said work holder, a stationary shaft extending through said hollow shaft, and an annular cam secured upon said stationary shaft for engagement by said heads.

2. In a blank grinding machine, partially overlapped rotary blank holding and grinding wheels presenting confronting fiat end faces inclined slightly relative toeach other, and means for supporting and rotating said Wheels so that the blanks carried on the flat end face of said blank holding wheel are rotated in an inclined plane, said blank holding wheel including a plurality of spaced radial blank supports fixedly carried on its end face each defining a blank supporting seat extending radially outwardly toward the plane of the grinding face of said grinding wheel, and clamping means for holding the blanks on said supports, the grinding arc of movement of each blank being substantially coextensive with the overlap of said wheels and the inclination of said inclined plane being such to progressively cause only the edge of each blank to be fed transversely closer to said grinding face as the blank is rotated through said grinding arc and tobring the blank edge to be ground into closest cooperation with said grinding face as the blank is traveling the last quarter of said grinding arc.

3. In a blank grinding machine, a rotary grinding element presenting an outer grinding flat side face, a rotary work holding member supported on an axis extending in the same general direction as that of the grinding element axis but being slightly inclined relative to and towards said grinding element axis, said work holding element having a fiat end face overlapping only a portion of said outer grinding face and having a plurality of blank receiving supports, and clamps for holding the blanks on said supports so that each blank extends radially outward and toward the plane of said grinding face whereby said blanks are rotatable in a plane inclined to that of the grinding face, and means for rotating said work holder to cause said blanks to be progressively fed inwardly against and over said grinding face, each blank support being constructed to carry a blank having at least two cutting edges disposed at an acute angle to each other, said supports being alternately reversed in position to support alternate blanks in reverse positions from that of the other blanks so that one set of blanks each presents one edge to be ground and the other and alternate set of blanks each presents a different edge of the blanks to be ground, the grinding arc of movement of each blank being substantially coextensive with the overlap of said wheels and the inclination of said inclined plane being such to progressively cause only the edge of each blank to be fed transversely closer to said grinding face as the blank is rotated through said grinding arc and to bring the blank edge to be ground into closest cooperation with said grinding face as the blank is traveling the last quarter of said grinding arc.

ARTHUR L. WARNER.

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